Datasets:

cwinkler

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patents_green_plastics_10k

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the invention provides biocompatible resorbable polymers , comprising monomer units having formula , formula , formula or formula . the polymers degrade over time when implanted in the body , and are useful as components of implantable medical devices .

the present invention is directed to a method for the lamination of metals , and especially copper , to the surfaces of fluoropolymers at temperatures substantially below the sintering temperatures or melting temperatures of the fluoropolymers . more specifically , the invention is directed to a method for surface modification of fluoropolymers by thermal graft copolymerization with concurrent lamination of a metal in the presence of a functional monomer . the process can be carried out under atmospheric conditions and in the complete absence of an added polymerization initiator . the so - laminated fluoropolymer - metal interfaces exhibit t - peel strengths of no less than 8 n / cm and delaminate via cohesive failure inside the fluoropolymer .

a device of color 3d printing and the method thereof are disclosed . the method is adapted to print a color 3d part . the device of color 3d printing at least has a print bed and a print head . the method includes the steps as follows . a solid model of the color 3d part is established , wherein the solid model at least consists of plural points and a color data for each thereof . a temperature / color table for a plastic material is then established . the table consists of plural heating temperatures for transforming the plastic material to specific colors respectively . the coordinates and color data of each point are obtained according to a predetermined sequence . the positions of the print bed and the print head are controlled according to obtained coordinates . the plastic material is heated according to the color data and the temperature / color table and is printed by the print head .

a plastics extruder in operative association with a control arrangement is disclosed . the plastics extruder includes a screw extruder , a screen downstream of the screw extruder , a throttle located between the screw extruder and the screen , a moulding tool downstream of the screen , and a melt index measuring device . the measuring device includes a metering pump whose rotational speed is controllable and which is provided with a rotational speed indicator , a measuring nozzle disposed in a sample flow channel , and pressure and temperature sensors connected to the sample flow channel directly upstream of the inlet of the measuring nozzle . the sample flow channel is adapted to be located downstream of the screen pack and upstream of the moulding tool . for the purpose of regulating the viscosity of the plastics material melted in the screw extruder , the throttle cross - section is variable by a servomotor connected to the output of a programmable two - coordinate controller . the characteristic of the controller provides a desired value output and can be predetermined as a temperature - pressure characteristic when the metering pump is operated with constant delivery , or as a temperature - delivery characteristic when the metering pump is operated with a constant pressure drop via the measuring nozzle while the temperature sensor is connected to one of two actual value inputs of the two coordinate controller . either the pressure sensor or the rotational speed indicator is connected to the second actual value input .

polyolefinic compositions comprising : 1 - 99 % by weight of a propylene amorphous polymer , and 1 - 99 % by weight of a copolymer selected from a copolymer of propylene with ethylene and / or alpha - olefins c 4 - c 10 , and a composition comprising : 10 - 50 % by weight of an isotactic polypropylene with ethylene and / or alpha - olefins c 4 - c 10 ; 0 - 20 % by weight of a copolymer containing ethylene , insoluble in xylene , and 40 - 80 % by weight of an elastomeric copolymer of ethylene with propylene and / or alpha - olefins c 4 - c 10 , optionally with small amounts of diene . these compositions are endowed with good mechanical and optical properties and are suitable for the manufacture of articles for biomedical applications .

the invention relates to self - supporting , vertically free - standing display packages for displaying a product . more particularly , the invention relates to a blister pack display package having a preformed product closure attached to a paperboard back and provided with a unitary support structure . another aspect of the invention concerns its manufacture by molding a plastic sheet into said blister package in such manner as to advantageously strengthen said unitary support structure along the edge of its contact with the surface on which it stands .

the invention provides for preparing a polymer - active agent conjugate , the method comprising the steps of reacting an amino acid derivative with a biologically active agent under conditions to form a polymer - active agent conjugate .

the invention is based on the discovery that the sequence of monomers in a polymeric biomolecule can be determined in a self - contained , high pressure reaction and detection apparatus , without the need for fluid flow into or out from the apparatus . the pressure is used to control the activity of enzymes that digest the polymeric biomolecule to yield the individual monomers in the sequence in which they existed in the polymer . high pressures modulate enzyme kinetics by reversibly inhibiting those enzymatic processes which result in a higher average activation volume , when compared to the ground state , and reversibly accelerating those processes which have lower activation volumes than the ground state . modulating the pressure allows the experimenter to precisely control the activity of the enzyme . conditions can be found , for example , where the enzyme removes only one monomer from the biomolecule before the pressure is again raised to a prohibitive level . the identity of the single released nucleotide or amino acid can be determined using a detector that is in communication with a probe in the detection zone within the reaction vessel .

a process and apparatus for making a metal annular member of precise tolerances . the workpiece is formed by welding sheet metal into a tube . the workpiece is presized by expanding it and plastically stretching it into a precise predetermined annular configuration adapted to closely fit a post element having a pair of spaced annular liquid seals mounted thereon . the post element and workpiece are positioned within an annular lower outer die . a cup - shaped upper outer die is placed over the lower die and is used to compress the post element to squeeze the liquid seals to expand them . forming of the workpiece is accomplished by pumping liquid into the post element between the liquid seals forcing the workpiece to expand against the outer dies and the sheet metal at the end portions of the workpiece to feed into the part being formed from between the outer dies and the post element .

an automatic high - speed wrapping system for wrapping packages in heat sealable thermoplastic film includes a film delivery unit wherein the film is dispensed and wrapped around the packages at a high rate of speed as the packages travel through the system . the packages travel continuously in a straight line through the system and are delivered at the input end of the system by a feed conveyor into a wrapping station where the packages are surrounded by the film , thence to the side sealing mechanism which forms a seal while severing the salvage from the packages , then into an end sealing mechanism where both ends of the packages are sealed and the film web connecting succeeding packages is severed . the film is delivered to the wrapping station in two plies and subsequently inverted for wrapping around the products . the positions of the wrapping station and film delivery units are adjustable to efficiently accommodate a variety of product heights while providing proper film delivery geometry .

a ceramic fiber band that can fulfill a plurality of functions in connection with the injection and / or extrusion process of an injection molding or extrusion apparatus , thereby reducing overall energy costs and creating a safer working environment . the ceramic band , being an insulator and having heating and / or cooling elements with a faster response contained therein , exert the desired heating / cooling effect upon the barrel portion of the injection / extrusion machine thereby raising , lowering , or maintaining the temperature of the fluid plastic compound passing through the barrel .

heterofunctional polyethylene glycol or polyethylene oxide , represented by one of the following formula to : wherein : m is an integer from 5 to 10 , 000 ; n is an integer from 1 to 20 ; each r is independently an organic substituent , preferably an hydrocarbon substituent that preferably comprises at least one heteroatom , each a is independently an alkyl , a substituted alkyl group or an hydrogen atom , and the salts thereof . the above polymer architectures are produced by means of living anionic polymerization . since the polymerization procedure is a living process , it is possible to tailor the polymer molecular weight from oligomer containing few units of ethylene oxide to over 10 , 000 units of ethylene oxide units . these oligomers or polymers are expected to exhibit excellent biocompatibility , and are also expected to be utilized in the field such as carriers for drug delivery or diagnostic reagents .

a joint compound which remains flexible upon curing and therefore tailored for manufactured housing processes , comprising an acrylate , a biocide , a reinforcing agent , a latex , a first surfactant , a plasticizer , a coalescent agent , a fungicide , a filler , and a second coalescent , all materials being present in predetermined weight percents . a method for producing flexible joints is also provided whereby joints formed by abutting panels are sealed with a joint compound , said joint compound having the characteristic of remaining flexible upon curing or setting .

crosslinked polymeric compositions capable of forming continuous matrices for liquid absorbent , semi - interpenetrating polymer networks . these networks are blends of polymers wherein at least one of the polymeric components is crosslinked after blending to form a continuous network throughout the bulk of the material , and through which the uncrosslinked polymeric components are intertwined in such a way as to form a macroscopically homogeneous composition . the compositions of this invention can be used to form durable , ink absorbent , transparent graphical materials .

fluidic methods and devices for conducting parallel chemical reactions are disclosed . the methods are based on the use of in situ photogenerated reagents such as photogenerated acids , photogenerated bases , or any other suitable chemical compounds that produce active reagents upon light radiation . the present invention describes devices and methods for performing a large number of parallel chemical reactions without the use of a large number of valves , pumps , and other complicated fluidic components . the present invention provides microfluidic devices that contain a plurality of microscopic vessels for carrying out discrete chemical reactions . other applications may include the preparation of microarrays of dna and rna oligonucleotides , peptides , oligosaccharides , phospholipids and other biopolymers on a substrate surface for assessing gene sequence information , screening for biological and chemical activities , identifying intermolecular complex formations , and determining structural features of molecular complexes .

method and assembly for reinforcing flexible graphite by fusion bonding a film of thermoplastic polymer to the flexible graphite to form a laminiated product . one side of the thermoplastic polymer is raised to its softening temperature to cause it to bond to the flexible graphite while the opposite side thereof is maintained at a temperature below its softening point .

thermoforming apparatus having a heating station and a forming station provided with upper and lower heaters for softening the thermoplastics sheet material . one of the heaters is movable between the heating and forming stations and is arranged to convey heated sheets from the heating station of the forming station .

the present invention relates to a process for producing a polypropylene - ethylene block copolymer by a continuous multi - stage polymerization comprising a first stage in which polypropylene is polymerized in a first polymerization vessel in the presence of a propylene polymerization catalyst , and a second stage in which propylene and ethylene are copolymerized in a second polymerization vessel , wherein the polypropylene slurry discharged from the first polymerization vessel is supplied to a concentrator to separate said slurry into a concentrated polypropylene slurry and a supernatant liquid , the concentrated polypropylene slurry is then introduced through an upper part of a hydraulic sedimentation classifier to be contacted with a countercurrent of the upward flowing of the supernatant fluid introduced through a lower part of said classifier to obtain hydraulically sedimented polypropylene , and non - hydraulically sedimented polypropylene ; the thus obtained hydraulically - sedimented polypropylene is then supplied to the second polymerization vessel or to a further propylene polymerization vessel and the non - hydraulically sedimented polypropylene is then recycled from the classifier to the first polymerization vessel . the present process produces a propylene - ethylene block copolymer having excellent characteristics of cold shortness and high impact strength .

a system for delivering a growth hormone releasing peptide including a peptide , or a pharmaceutically acceptable salt form thereof , alternatively conjugated to a polymer via a biodegradable bond and dissolved in a liquid medium . because extra - cellular fluids in vivo provide the appropriate environment to efficiently degrade peptides , the growth hormone releasing peptide will maintain chemical integrity and remain substantially coupled to the polymer while circulating through the body . the therapeutic agent is , therefore , protected from degradation and clearance .

the water purification cartridge treats water with a halogen liberated from halogenated hydantoinyl resins and polymers , resulting in the safe , complete , and economical purification of non - potable water at low flow rates typically found in gravity feed filtration systems and at water pressures of less than 1 psig . the cartridge of the invention purifies non - potable water of bacteria , viruses , and some protozons without the need for additional power sources or risk to the consumer for exposure to chemicals that have been identified to have harmful , long - term effects . the cartridge described herein enables a gravity fed water purification system by combining the cartridge with conventional filters , such as porous diatomaceous earthen ceramic water filters or activated carbon filters packed either with granular activated carbon or block .

this invention pertains to a synergistic blend comprised of a polyamino acid and an anionic carboxylic polymer . the blend is able to effectively stabilize the calcium salts that lead to scale formation in evaporative systems . this blend shows high levels of efficacy in the acidic high conductivity waters found in many evaporative systems such as sugar and biorefining .

a reusable , washable , plastic , collapsible bin includes a plastic base . four walls extend upwardly from the base and interlock with one another near the corners . straps around the walls hold the walls together temporarily during use and keep the walls interlocked with one another . after use , the straps are removed and the walls can easily be removed from the base . the walls and base are then washed for subsequent reuse .

a purified thermostable enzyme is derived form the thermophilic archaebacterium archaeoglobus fulgidus . the enzyme can be native or recombinant , is stable under pcr conditions and exhibits double strand specific exonuclease activity . it is a 3 ′- 5 ′ exonuclease and cleaves to produce 5 ′- mononucleotides . thermostable exonucleases are useful in many recombinant dna techniques , in combination with a thermostable dna polymerase like taq especially for nucleic acid amplification by the polymerase chain reaction .

a microwave - resistant and waterproof security tag for use with food products , especially meat products . the security tag includes a pair of single , open loop conductive traces in between which is disposed a similarly - shaped dielectric layer . this combination is encapsulated within plastic membranes or covers that are sealed at their common edges . the preferred embodiment includes rectangularly - shaped single , open loop conductive traces with rounded corners and with one end of each trace forming a capacitor plate . the width of each trace is at least 1 / 10 of the length of the security tag .

the present invention discloses a thermoplastic polyurethane which is comprised of the reaction product of a hydroxyl terminated polyester intermediate , a polyisocyanate , and a glycol chain extender ; wherein the hydroxyl terminated polyester intermediate is comprised of repeat units that are derived from 1 , 3 - propylene glycol and a dicarboxylic acid ; wherein the hydroxyl terminated polyester intermediate has a number average molecular weight from 500 to 10 , 000 ; and wherein the thermoplastic polyurethane includes hard segments that are the reaction product of the polyisocyanate and the glycol chain extender . this thermoplastic polyurethane is unique in that it has a greatly reduced tendency to bloom . this is highly desirable in applications where high clarity is desired because blooming causes articles containing the thermoplastic polyurethane to be hazy or foggy in appearance . blooming can also reduce the ability of an article made with the thermoplastic polyurethane to be securely bound to another article with an adhesive .

the surfaces of nano silica particles are modified with siloxane substituents containing aldehyde functional groups providing particles which are readily incorporated into compositions , such as polymeric coating compositions , to improve scratch resistance , dirt pick - up resistance , anti - adhesion properties and while maintaining excellent film forming properties . provided are the novel silica particles , a simple economic process for their preparation and dirt repellent coatings and polymeric molding compositions containing them .

the invention relates to a biodegradable chewing gum comprising one or more conventional chewing gum components and as gum base at least one biodegradable polymer selected from the group of polyesters and polycarbonates .

protein microspheres are formed by phase separation in a non - solvent followed by solvent removal . the preferred proteins are prolamines , such as zein , that are hydrophobic , biodegradable , and can be modified proteolytically or chemically to endow them with desirable properties , such as a selected degradation rate . composite microspheres can be prepared from a mixture of proteins or a mixture of proteins with one or more bioerodible polymeric materials , such as polylactides . protein coatings can also be made . compounds are readily incorporated into the microspheres for subsequent release . the process does not involve agents which degrade most labile proteins . the microspheres have a range of sizes and multiple applications , including drug delivery and delayed release of pesticides , fertilizers , and agents for environmental cleanup . selection of microsphere size in the range of less than five microns and mode of administration can be used to target the microparticles to the cells of the reticuloendothelial system , or to the mucosal membranes of the mouth or gastrointestinal tract . larger implants formed from the microspheres can also be utilized , especially for agricultural applications .

methods to expand polymer tubing with desirable or optimum morphology and mechanical properties for stent manufacture and fabrication of a stent therefrom are disclosed .

the present invention relates to novel synthetic methods for peg - maleimide derivatives , specifically , novel synthetic methods for peg - maleimide . the final products thereof are useful as a pegylation reagent in the field of bioengineering and the medicinal field or the preparation of medical appliances and by conjugating with certain moieties or specific domains of polysaccharides and biological proteins such as antibodies as a bio - compatible or bio - degradable polymer .

the present invention includes a method for treating an aneurysm . the method includes providing a biocompatible polymeric string and transporting the string to an aneurysm . the aneurysm is filled with the string . the string is cut when the aneurysm is substantially filled .

the invention provides a method of efficiently producing branched , cyclic glycerol - based polyols with a co - product as anti - biodegrading agent from inexpensive readily available glycerol monomer . the method involves polymerizing glycerol or glycerol with at least another monomer to multiple other monomers in the presence of particular amount of a strong base as the catalyst under a particular distillation environment . the polyol produced by the inventive method is beneficial of reducing scales in bayer liquid for aluminum production process and improving brightness of coated paper substrates without greening effect .

the present invention relates to a sample chamber for a liquid , wherein at least one part in the interior of the sample chamber comprises a fluid - absorbent and / or fluid - permeable plastic , which is essentially degasified in at least one area and / or in which a predetermined fluid and / or predetermined solid is stored in soluble form in at least one area .

a light altering rub rail comprising an elastic , semi - rigid translucent polymer base having at least a body portion with proximal and distal ends , top and bottom ends and front and rear faces ; an access flap forming the majority of the base front face creating a gap in the base ; a light source embedded within the gap in the base ; a plurality of mounting lobes at the proximal and distal end portions ; and a plurality of linear light refractors embedded within the base wherein the gap in the base may be sealed to create a fully enclosed water - proof housing .

the present invention provides a biochip cartridge wherein an elastic body is used for a substrate member in order to stabilize the feeding of blood or solution and whereby it is possible to avoid the risk of accidental contact of the operator with solutions due to mishandling . the biochip cartridge comprises a tabular substrate member formed using an elastic material and a flexible cover air tightly attached to the surface of the substrate member , wherein at least an area for storing biopolymers , an area for detecting desired biopolymers from the biopolymers that have been preprocessed , and a flow path for connecting the areas is formed on the substrate member , so that biopolymers can be successively moved from the biopolymer storage area to the biopolymer detection area through the flow path .

the present invention relates to a process for liquefaction and saccharification of polysaccharide containing biomasses , having a relatively high dry matter content . the present invention combines enzymatic hydrolysis with a type of mixing relying on the principle of gravity ensuring that the biomasses are subjected to mechanical forces , primarily shear and tear forces . furthermore , the present invention relates to the further utilization of such processed biomasses , e . g . for subsequent fermentation into bio - ethanol , bio - gas , specialty carbohydrates for food and fees as well as carbon feedstock for processing into plastics and chemicals .

an apparatus useful for the extrusion of high melting slippery plastic resins comprising a screw element which operates rotatably within a close - fitting barrel having cut into the interior surface thereof a shallow and narrow groove of the same hand and substantially the same lead as the screw element .

radical anions for use in the fragmentation of positively charged biopolymer ions by means of electron transfer are produced from substances previously unknown for use as etd production substances . the inventive substances produce radical anions that lead to electron transfer dissociations with a high yield of fragment ions . the substances have high volatility that allows them to be kept in unheated containers outside the vacuum system and transported into the vacuum system to an in vacuum electron attachment ion source via unheated lines and low molecular weights that allow the measurement of even very light fragment ions . in one embodiment , a suitable substance is 1 - 3 - 5 - 7 - cyclooctatetraene .

a synthetic process of producing liquid tin alkoxides for use as either catalysts in the synthesis of lactide or as initiators in the polymerization of cyclic ester monomers to yield biodegradable polyesters is described . the synthetic process employs anhydrous tin chloride dissolved in n - heptane mixed with dry diethylamine . alcohols , roh , in which the r groups are n - c 4 h 9 , n - c 6 h 13 , and n - c 8 h 17 are added to the reaction mixture and stirred for 12 hours . the reaction mixture is then filtered under nitrogen or argon before being evaporated to dryness to yield the three tin alkoxides , namely : tin n - butoxide , tin n - hexoxide , and tin n - octoxide . all three tin alkoxides are viscous , dark yellow liquids which are highly soluble in most common organic solvents . furthermore , they can all be stored under an inert atmosphere for long periods without any significant change in their reactivity and therefore , in their effectiveness as catalysts / initiators .

a portable , lightweight , easy - to - carry , reusable , durable , and environmentally - friendly assembly for sterilizing contaminated equipment using conditions of a chemical sterilant , heat , and humidity generated in situ without requiring external electricity , fuels , or other exogenous energy sources for operation . the carry assembly includes a plastic carry - case or insulated aluminum pressure vessel having an inner chamber for accepting microbiologically contaminated objects , a vessel disposed in the chamber for serving as a reaction chamber and / or boiler , a chemical combination which upon mixing generates at least minimally sufficient conditions of the sterilant , heat , and humidity to effect sterilization of the objects , and outlet valves mounted on the carry - case for controllably venting pressures above ambient air pressure .

this invention relates primarily to organofunctional monomers , predominantly dimethacrylates and / or diacrylates containing one or more ( predominantly two carboxyl groups , with moieties that provide sufficient affinity with water to allow any desired amount of water and / or miscible fugitive solvents to be mixed homogeneously with these monomers and formulations containing them . the activity of water in the monomer formulations can be adjusted so that it is equal to the water activity in biological tissues . this promotes biocompatibility and enhances the adhesive characteristics of polymers prepared from these formulations . probability statistics are disclosed that optimize the compositions of polymer reaction products . also disclosed are novel , dual - purpose synthesis reaction monomers , catalysts , stabilizers , polymerization initiators and / or cophotoinitiators that have solubility and surface - activity characteristics such that they will not become separated by partitioning during penetration of hydrated layers on or in the substrate adherends . these formulations may be used for light - cured or chemical - cured bonding to soft or hard tissues , metal , porcelain , ceramic or other surfaces . a potential application for the composition is the holding together , by an overlying layer of resulting polymer , tissues adjacent to incisions and wounds . the polymerized composition might replace suturing , and allow for the healing of soft tissues .

in accordance with the present invention , there are provided compositions and methods useful for the in vivo delivery of substantially water insoluble pharmacologically active agents in which the pharmacologically active agent is delivered in the form of suspended particles coated with protein . in particular , protein and pharmacologically active agent in a biocompatible dispersing medium are subjected to high shear , in the absence of any conventional surfactants , and also in the absence of any polymeric core material for the particles . the procedure yields particles with a diameter of less than about 1 micron . the use of specific composition and preparation conditions , and careful selection of the proper organic phase and phase fraction , enables the reproducible production of unusually small nanoparticles of less than 200 nm diameter , which can be sterile - filtered . the particulate system produced according to the invention can be converted into a redispersible dry powder comprising nanoparticles of water - insoluble drug coated with a protein , and free protein to which molecules of the pharmacological agent are bound . this results in a unique delivery system , in which part of the pharmacologically active agent is readily bioavailable , and part of the agent is present within particles without any polymeric matrix therein .

an assembly for the receiving of a plurality of plastic parts initially interconnected to one another by runner structures in an array and formed from a multi - cavity plastic mold such that the subject assembly separates the plastic parts from the runner structure , ejects and delivers the runner structure into a recycling assembly and concurrently but independently delivers each of the plastic parts into separate containers through the provision of a delivery structure associated with the subject assembly .

an apparatus and method for the destruction of terrorist weapons , including explosives chemical and biological agents , by detonation in an enclosed double - walled steel explosion chamber having its walls , access door and floor filled with granular shock damping material . the chamber is vented through orifices into vent pipes which converge in a manifold which exhausts into an expansion tank or scrubber for cooling , testing , and environmental treatment of the explosion products . a weapon to be destroyed is placed into the chamber with a donor explosive charge and held in place by a disintegratable string hammock , along with one or more plastic polymer film bags containing water . after closing the access door , the donor charge is detonated by an electrical detonation means . for use in destroying known or suspected chemical or biological weapons the donor charge is augmented with an oxidizing material such as potassium nitrate , and the resulting fireball is enhanced by powdered metal such as aluminum , to achieve an instantaneous pressure of 100 kilobars and instantaneous temperature of 3 , 000 degrees celsius .

a laminate material having nonslip characteristics on one surface and a smooth surface on the other side is provided . the material is created by laminating together a smooth film and a plastic foam surrounding a scrim having nonslip characteristics .

a method for manufacturing plastic containers in which , for each container , a plastic preform containing air is supplied ; the preform is heated at a preform temperature over the glass temperature of the preform material , the preform is inserted in a mold having a mold cavity ; and the preform is expanded to a container having the shape of a mold cavity by a forming liquid . the method also includes , between steps and , the injecting of a gaseous product into the preform containing air , wherein the gaseous product is absorbable by the forming liquid . the injection conditions of the gaseous product are selected such that the injected gaseous product expels the air out of the preform .

a hot melt adhesive polymer is applied to a diaper backsheet by an aligned series of meltblowing units which are selectively operable to apply the coating in the desired geometry on the diaper backsheet .

a method of producing a composition which is composed of from 5 to 50 wt . % of caoutchouc , preferably natural caoutchouc ; from 4 to 25 wt . % of starch powder ; from 10 to 50 wt . % of one of polybetahydroxybutyrate or cellulose ; and from 0 to 15 wt . % of auxiliary agent , and which is biodegradable includes providing caoutchouc in one of flaked or granular form ; providing initial materials selected from the group consisting of starch , polybetahydroxybutyrate , cellulose , and auxiliary agent , in ground form as one of a powder or granulated ; homogeneously mixing the initial materials into the caoutchouc to provide a homogeneous mixture : plasticizing the homogeneous mixture by heating in one of a screw - type extruder or injection molding machine to provide a plasticized mass ; and ejecting the plasticized mass from the extruder or injection - molding machine and allowing the mass to cool . preferably , plasticizing is carried out of a temperature ranging from 170 ° c . to 180 ° c .

a method of making a carboxylated carbohydrate is disclosed , cellulose being a preferred carbohydrate material . carboxylated cellulose fibers can be produced whose fiber strength and degree of polymerization is not significantly sacrificed . the method involves the use of a catalytic amount of a hindered cyclic oxammonium compounds as a primary oxidant and chlorine dioxide as a secondary oxidant in an aqueous environment . the oxammonium compounds may be formed in situ from their corresponding amine , hydroxylamine , or nitroxyl compounds . the oxidized cellulose may be stabilized against d . p . loss and color reversion by further treatment with an oxidant such as sodium chlorite or a chlorine dioxide / hydrogen peroxide mixture . alternatively it may be treated with a reducing agent such as sodium borohydride . in the case of cellulose the method results in a high percentage of carboxyl groups located at the fiber surface . the product is especially useful as a papermaking fiber where it contributes strength and has a higher attraction for cationic additives . the product is also useful as an additive to recycled fiber to increase strength . the method can be used to improve properties of either virgin or recycled fiber . it does not require high α - cellulose fiber but is suitable for regular market pulps .

a process of extrusion molding plasticized vulcanizable or cross - linkable rubber or synthetic resin materials , comprising the steps of heating said materials to an elevated temperature in a short time immediately before a molding die and vulcanizing or cross - linking the materials in the manner of maintaining said elevated temperature substantially while the materials are passing through the die or for a while after they have passed through the die , thereby obtaining mold goods .

this invention is the design and synthesis of a caprolactone monomer which bears a pendant protected carboxyl group . this monomer has been copolymerized with caprolactone in varying ratios . after polymerization , the protecting group can be removed and an antibiotic can be attached as a new pendant group . the bioactivity of the antibiotic - bound poly polymer is described .

each platform mounted mold assembly for plastic tubing includes a circuit board containing parameters defining elements of the forming , molding , tipping or welding operation to be undertaken on the tubing . a control unit includes an rf generator for providing the rf energy to effect the forming , molding , tipping or welding process , a source of air under pressure to operate the mechanical elements attendant each mold assembly , various sensors and a multiplex unit . in operation , the control unit serially addresses each of the mold assemblies , senses the parameters attendant the mold and applies the appropriate power level of rf energy for a specific duration and temperature while activating the mechanical aspects of the mold assembly . the mold assemblies may be serially activated through a multiplex unit or in a particular sequence that may be operator controlled .

a snowmobile frame is described , with a tunnel having an inverted u - shape . an engine cradle is attached to a forward portion of the tunnel . a suspension assembly is disposed forwardly of the engine cradle . at least one support member supports the suspension assembly on the engine cradle . the at least one support member forms a crumple zone between the suspension assembly and the engine cradle . the at least one support member resists plastic deformation in response to the first predetermined force exerted on the suspension assembly . the at least one support member undergoes plastic deformation in response to a second predetermined force being exerted on the suspension assembly . the second predetermined force is greater in magnitude than the first predetermined force . the tunnel resists plastic deformation in response to the second predetermined force .

container transport apparatus for transporting containers such as plastic bottles and the like which are subject to damage without damaging the containers . the container transport apparatus includes container guiding members for guiding containers such as plastic bottles through a bottle rinser or the like and elongated endless belt members for contacting the sides of the containers to move the containers along the path of the container guiding members . the container transport apparatus eliminates the problems associated with conventional bottle rinsers and the like when used with non - rigid bottles .

a dual constituent container includes a compartment for liquids and an elongate inwardly directed recess open to the container exterior and isolated from the compartment . the container is formed by blow molding , using a mold that incorporates a shaping feature projected longitudinally into the mold cavity . the shaping feature incorporates an arrangement of longitudinal channels having a channel width such that when a thermoplastic preform is expanded into contact with the mold cavity walls and the shaping feature , portions of the expanded preform span the channels and cooperate with the channels to provide passages that accommodate pressurized air to facilitate separation of the expanded preform from the shaping feature . the same portions of the expanded preform can partially protrude into the channels , thus to form longitudinal ribs along the recess which aid in frictionally holding a secondary constituent .

biodegradable anionic polymers are disclosed which include recurring polymeric subunits preferably made up of dicarboxylic monomers such as maleic anhydride , itaconic anhydride or citraconic anhydride . free radical polymerization is used in the synthesis of the polymers . the polymers may be complexed with ions and / or mixed with fertilizers or seeds to yield agriculturally useful compositions . the preferred products of the invention may be applied foliarly or to the earth adjacent growing plants in order to enhance nutrient uptake by the plants .

the present invention relates to apparatus for measuring the genetic sequence of electrically charged biopolymers by means of hybridization . the measuring apparatus comprises a container that contains a biopolymer and can be removed from the apparatus , and electrodes that apply an electric field to the container and are electrically insulated from the container . when an electric field is applied to the container , suspended biopolymeric molecules are attracted toward the positive electrode , thus increasing the speed of hybridization .

a process for producing containers involves a tube and at least one separating partition , both formed from plasticized synthetic material . the partition extends within the tube . the tube and partition are extruded into an opened blow mold . the blow mold is then closed , and the tube is expanded by producing a pressure gradient that acts upon the tube . the pressure gradient is applied to expand the tube against the molding wall of the blow mold to form the container . the end of the tube that is the front end during the extrusion step and the front end of every separating partition are welded together by closing the opened blow mold , thereby closing the base of the container that is linked with every separating partition . the tube is expanded by adding blowing air from the end of the closed blow mold that is opposite to the container base and that is assigned to the container neck in such a manner that the blowing air has an expanding effect on both sides of the separating wall , thereby forming chambers in the container that are separate from one another .

a method for extruding a thermoplastic polymer / wood fiber composite utilizes styrene acrylonitrile as the principal thermoplastic component . acrylonitrile butadiene styrene is used as a stiffener and modifier to prevent degradation of a foaming agent &# 39 ; s efficacy . the method of the invention and the extrusion produced by the inventive method are particularly applicable to extrusions having high aspect ratio cross - sectional shapes and extrusions in which the ratio of wall thickness to interior volume is large .

novel membranes comprising various polymers containing heterocyclic nitrogen groups are described . these membranes are usefully employed in electrochemical sensors , such as amperometric biosensors . more particularly , these membranes effectively regulate a flux of analyte to a measurement electrode in an electrochemical sensor , thereby improving the functioning of the electrochemical sensor over a significant range of analyte concentrations . electrochemical sensors equipped with such membranes are also described .

a moving web of material having a high tendency to elongation under stress , such as woven and non - woven plastic fiber or filament webs , is cut by the combined action of a cutting knife which executes its cutting stroke generally in line with and upstream of the web and a grab knife which holds the web at a station spaced closely downstream from the path of the cutting knife and thereby isolates the small length of web between the two knives while the cutting knife completes its stroke .

natural or synthetic rubber surgical elements such as tubing , catheters , drains and gloves are &# 34 ; lubricated &# 34 ; so as to prevent sticking during storage , and permit easier emplacement , such as putting on the gloves by a surgeon or nurse , by applying to the surface of the rubber element a finely divided biodegradable powder consisting essentially of an enzymatically degradable form of poly selected from the group consisting of poly - d - glucosamine ], poly - d - glucosamine ], poly - d - glucosamine ], and poly itself this powder is readily absorbed by living tissue without deleterious tissue reaction , thus minimizing tissue reaction from the transfer of the powder from the element such as a glove to internal sites in a subject . the gloves may be packaged in a strippable laminate package . the polymers are derived from chitin .

the invention relates to a composition for use in the production of an article of manufacture , and in particular , to the manufacture of wall and corner guards . the composition includes a biopolymer in combination with petg as well as a modifier . the biopolymer and modifier are preferably produced from an annually renewable source such as corn or sugar as opposed to traditionally used petroleum based plastics . in this manner , the composition of the invention is relatively environmentally friendly as compared to known compositions while maintaining many of the desirable qualities thereof . in addition , the production of the articles of manufacture results in the consumption of fewer fossil fuels and less production of pollutants .

oral compositions for the local administration of a therapeutic agent to a periodontal pocket of a patient for alleviating dental disease comprise a plurality of dry , discrete microparticles each of which comprise an effective amount of at least one therapeutic agent dispersed in a matrix comprising a biocompatible and biodegradable polymer . apparatus and methods are also provided for the dispensing of the dry microparticles to the periodontal pocket whereby they become tacky and adhere to the involved tissue so as to induce long term therapeutic benefits .

disclosed is a gas generating polymer compound that when irradiated with light or other radiation sources makes a solid to gas phase transition due to chemically catylized degradation , irradiative degradation or both . this provides a low cost , stable and easily manufactured means of gas production . also disclosed are possible uses for the gas generator such as a low cost micro thruster .

a biodegradable intra vaginal device for insertion into the vagina of an animal useful for herd oestrus synchrony purposes , the device is intra vaginally insertable , intra vaginally retainable and withdrawable by virtue of its ability to change its geometry yet is formed at least almost exclusively from a cyclodextrin and progesterone impregnated moulded matrix of a polyester polymer ) or a starch - like polysaccharide polymer . there is preferably a loading of progesterone of from 0 . 1 to 3 gms . the surface area of the impregnated matrix is preferably from 15 to 200 cm 2 . related methods and uses also form part of the invention .

a process is disclosed for obtaining olefin - polar comonomer resin in fibrous form . according to the invention , an olefin - polar comonomer resin such as an ethylene - vinyl acetate copolymer is vigorously agitated in molten form in water in the presence of a resin dispersion - forming amount of an alkali metal soap such as sodium stearate and a fiber - forming amount of base such as sodium hydroxide at a temperature below the degradation temperature of the resin to provide a dispersion of said resin in which a substantial number of the individual resin particles are in the form of a fiber possessing an average length of from about 50 to about 2500 microns and an average length to diameter ratio of at least about 3 : 1 . following cooling of the dispersion to below the solidification point of the resin , the resin fiber may be recovered employing known and conventional means , e . g ., filtration , centrifugation , etc .

a composite vehicle wheel having a disk , a rim circumscribing the disk , and an ornamental metal - plated plastic overlay attached to the outboard surface of the disk . the overlay has a pair of oppositely disposed surfaces which form interior and exterior surfaces of the overlay . the interior surface mates with at least a portion of the outboard surface of the wheel while the exterior surface has a metal layer plated thereon . the overlay is formed from a relatively thin plastic panel such that the exterior surface uniformly and closely conforms to the outboard surface of the wheel and the metal layer is substantially flush with the adjacent portions of the outboard surface to provide a pleasing aesthetic effect to the wheel . the integrity of the metal layer is such that the overlay successfully meets corrosion resistance requirements for automobile manufacturers &# 39 ; original equipment .

a method of reducing a c — o bond to the corresponding c — h bond in a substrate , which could be a benzylic alcohol , allylic alcohol , ester or an ether bond beta to a hydroxyl group or alpha to a carbonyl group using a recyclable metal catalyst system . the recyclable catalyst system is also applicable to reducing a c ═ o bond to the corresponding c — oh bond and then c — h bond . these methodologies can be linked in one - pot to selective oxidation and depolymerizations of aromatic polyols such as lignin .

biodegradable and resorbable polymer pouches are described for use with cardiac rhythm management devices and other implantable medical devices , i . e ., a pouch , covering , or other receptacle capable of encasing , surrounding and / or holding the crm or other imd for the purpose of securing it in position , inhibiting or reducing bacterial growth , providing pain relief and / or inhibiting scarring or fibrosis on or around the crm or other imd . optionally , the biodegradable and resorbable pouches of the invention include one or more drugs in the polymer matrix to provide prophylactic effects and alleviate side effects or complications associated with the surgery or implantation of the crm or other imd .

this invention relates to bioabsorbable fibers , comprising a semicrystalline fiber - forming core polymer and a amorphous sheath polymer , wherein the core polymer and sheath polymer are separately melt extruded and connected to one another through an adhesive bond . the present invention also relates to reinforced composites of the bioabsorbable fibers , and to devices comprising the reinforced composites . the devices are suitable for in vivo implantation . some embodiments of the present devices can also support high loads , making them useful for fracture fixation and spinal fusion . the invention also relates to methods of making the various materials of the invention .

a heat - shrinkable film includes outer layers containing a polyester resin , and at least one inner layer being arranged between the outer layers and containing an olefinic resin including at least one ethylene - propylene - butene terpolymer . the film has an interlayer bonding strength between the inner layer and the outer layer of 3 . 0 n / 15 - mm or more . the inner layer may contain the ethylene - propylene - butene terpolymer in an amount of 45 percent by weight or more based on the total weight of the inner layer . the heat - shrinkable film is excellent in strength , abrasion resistance , solvent resistance , dimensional stability , and optical transparency , exhibits high shrinkability and high flexibility as a result of heating , and thereby yields beautiful finish after shrinkage . the heat - shrinkable film can be suitably recycled after use .

the present invention relates to a modified polyaryletherketone polymer with chemically modified surfaces with azides , alkynes , thiols , maleimides , sulfonylazides or thio acids , suitable for “ click ” reactions and to a process to obtain it . it also relates to the conjugated biomaterials derived thereof , paek type materials with surfaces modified with a rgd and / or ogp 10 - 14 peptidomimetics and to a process to obtain it . these materials are particularly useful for manufacturing medical devices . finally , the present invention also relates to a fluorescent paek material .

an apparatus for reshaping plastic preforms into plastic containers includes a plurality of blow - molding stations that each have at least one receptacle space , within which the plastic preforms can be expanded into the plastic containers . the apparatus also includes a conveying device that conveys the containers along at least one specified travel path , wherein the apparatus has a plurality of heating devices that are arranged along the travel path of each container , upstream of the blow - molding stations , wherein at least one heating device is allocated to at least one blow - molding station .

the present invention describes an injection molding process for manufacturing golf balls using thermoplastic materials . the injection mold is provided with a heating source and one or more valve gates . the heating source maintains the temperature of the molten thermoplastic material in the conduits through which it is delivered to the mold cavity , and the valve gate shuts off the flow of molten thermoplastic material to the mold cavity . advantageously , this process reduces or eliminates “ trim ” or waste material , and thus also minimizes the necessity to recycle thermoplastic material .

an industrially advantageous process described below has been established wherein tetrahydrofuran and a cyclic ether copolymerizable therewith are copolymerized by the use of a very small amount of a commercially available heteropolyacid as it is untreated , the heteropolyacid of the catalyst is recovered , recycled and reused in a simple way , and a high quality polyether substantially free from catalyst contaminants is obtained . a process for producing a polyether , comprising the steps of copolymerizing tetrahydrofuran and at least one cyclic ether copolymerizable therewith by the use of an untreated heteropolyacid as a catalyst in the presence of a hydroxy compound to form a reaction liquid , contacting the resulting reaction liquid with an anion exchange resin so that the heteropolyacid contained in the reaction liquid adsorb to the anion exchange resin to remove the heteropolyacid , desorbing the removed heteropolyacid from the anion exchange resin to reuse it as the catalyst , and reusing the anion exchange resin after the desorption as it is , thus to recycle and reuse both the catalyst and the anion exchange resin .

a method for molecularly crosslinking amino acid containing polymers by photoactivating chemical crosslinkers which have been combined with the polymers . collagen crosslinked by this method can be used as a bioadhesive for sutureless closures of the skin and eye or as a superhydrated material for contact lenses , moist bandage contact lens , lens or corneal implant material , or as a drug delivery mechanism .

embodiments of a multi - purpose implant for use in surgery , such as for reconstruction of soft tissues , are disclosed . in some embodiments , the implant includes elastic polymer film made from a suitable biologically compatible polymer . the implant also includes a reinforcement element forms from a polyurethane mesh or other strong and stable woven or unwoven synthetic material . the reinforcement element can be fully enclosed by the film so that only the film comes into contact with the organs and tissues . anti - adhesive properties or control over implant &# 39 ; s integration into a body can be determined by the preset surface structure of the implant , while physical and mechanical properties , such as strength and elasticity of the implant , are obtained by virtue of reinforcement element geometry .

an extruder screw designed to operate in a continuous diameter barrel - type housing having a variable flight width , helix angle and radical clearance along the length of the extruder screw to reduce extruder screw induced power consumption and stock temperature generation in the manufacture of linear low density polyethylene plastics .

a resealable can end is provided including a neck and a cooperating cap member which can be sealed onto and removed from the neck , and is capable of containing product under pressure or vacuum if desired . this end may be added , by convention seaming methods , such as roll seaming or by appropriate adhesive , to a container body , or may be formed integrally with container bodies . the venting feature of the end will achieve a controlled release of differential internal - to - ambient pressure upon initial opening of the cap , and may also provide resealed containment of partial contents retained in the container , although the contents will no longer be under pressure or vacuum , as the case may be . the end may be applied to , or incorporated in , containers made of various material , such as aluminum , coated steel , or selected plastics .

a method and apparatus for treating refuse by non - combustibly shrinking polyfoam plastics in the refuse . the trash is heated at a temperature between 250 ° and 500 ° for a minimum period of time . a rotatable chamber heats the refuse and transports the refuse for the minimum period of time . an operator controls the rate of rotation of the chamber and thus the time of heating in accordance with the moisture content of the refuse . a steam / air mixture used as a heat medium serves to kill bacteria in the refuse in addition to shrinking and drying the refuse .

a multilayered lightweight building board , comprising a support core , two cover layers on the support core , where the support core is made of laterally fused - together tubes . the tubes have an inner layer , and an outer layer , where the outer layer has a softening point 10 - 90 ° c . lower than the softening point of the inner layer . the lightweight building board is made from compatible thermoplastic materials , so they can be mechanically recycled by the customary processing methods for thermoplastics .

an improvement in a light therapy device including multiple light - emitting diodes positioned in a handheld portable device is disclosed . where the housing and the leds are configured to have direct contact with the skin or tissue of the user without any intermediary materials , and light the surface and underlying layers of tissue for photodynamic stimulation of the cells . two iterations of the device utilize light known to have a bactericidal effect in the case or acne or rosacea . the devices are fabricated from an injection molded plastic housing . the housing contains an arrangement of 36 - 72 leds on a circuit board in an arrangement to provide even lighting over the skin or tissue surface .

this invention comprises recycling and recovery processes for rugs , flooring , carpeting , carpet materials , and all other textiles particularly from waste carpet containing both synthetic and natural fibers and for backing materials , and more particularly for the separation and recovery of various nylon polymers as well as other polymeric fibers and materials for recovery and reuse .

a process is provided for fabricating coated particles of a substantially uniform particle size . the process comprises coating small particles of well - defined crystalline phases with a polymerized gel . the process results in a ball - type sol - gel coating of the particles to provide particles which have a narrow size distribution . in many instances , crystalline particles of irregular shape have a substantially spherical shape upon coating with the sol - gel . in instances where the core is a high melting point material , such as an oxide , nitride , or carbide , the coat formulation can effect a low sintering temperature , which permits forming films of the particles at a much lower temperature than would otherwise be possible .

a biocidal composition suitable for use as a stabilizer in polymer systems using 2 - mercaptopyridene - 1 - oxide or a derivative combined with an organophosphorous compound and a benzotriazole wherein the organophosphorous compound and the benzotriazole act together to stabilize the mercaptopyridene against degradation and discoloration of the polymer system .

the present invention provides a method of modifying the surface of a polymeric substrate , e . g ., to improve the wettability of the polymer film surface and / or alter the reactivity of the surface of the substrate by further oxidation , comprising exposing the substrate to a flame . the flame is supported by a fuel and oxidizer mixture that includes an effective amount , for modifying the polymeric substrate , of at least one oxygen - containing compound that functions as a fuel substitute . oxygen comprises between about 10 and 50 atomic percent of the compound . large increases in the astm wetting test over that reported with conventional flame - treating processes , have been observed in films treated according to this invention . in addition , significant increases in polymer film surface oxidation levels have been observed .

a method for preventing accumulation of organisms on a surface exposed to a marine environment . nano - particles are provided in a water soluble polymer . the nano - particles have a thickness of about 2 nanometers and a major surface area of about 3 microns and are treated by a quaternary ammonium salt . the treated nano - particles are mixed into the water soluble polymer material . this mixture can be applied to the exposed surface . biofouling is prevented by the sharpness of the nano - particles , sloughing of the water soluble material , and biocidal action caused by the quaternary ammonium salt .

a decorative laminate surface layer composition is prepared by selectively applying dissimilar thermoset or thermoplastic polymers to a decorative laminate facing sheet to achieve a brillant visual or pearlescent appearance .

a method and system for controlling dissolved oxygen levels in a secondary treatment system of a wastewater treatment facility that can employ a membrane bioreactor in which oxygen introduction into mixed liquor is controlled to prevent bulking and minimize generation of extra cellular polymeric substances . the control is exercised by insuring that dissolved oxygen levels within the mixed liquor do not fall below a minimum system level at which microorganism stress would occur . this is done by setting a minimum dissolved oxygen level control point equal to a sum of the minimum system level and an adjustment factor determined on the basis of oxygen uptake rate and time delays inherent in sensing oxygen levels and changes thereof within the mixed liquor . the minimum system dissolved oxygen level can be continually calculated on the basis of an inferred food to mass ratio that would vary with sensed mixed liquor suspended solids .

a method of making a contact lens involves depositing on a portion of a molding surface of a contact lens mold a colorant composition comprising a pigment , a copolymer of 2 - hydroxyethylmethacrylate and n - vinylpyrrolidinone , and a crosslinking monomer .

a mems device is manufactured by first forming a self - aligned monolayer on a carrier wafer . next , a first polymer layer is formed on the self - aligned monolayer . the first polymer layer is patterned form a microchannel cover , which is then bonded to a patterned second polymer layer on a device wafer to form microchannels . the carrier wafer is then released from the first polymer layer .

this invention relates to biocompatible , biodegradable thermoplastic polyurethane or polyurethane / ureas comprising isocyanate , polyol and a conventional chain extender and / or a chain extender having a hydrolysable linking group and their use in tissue engineering and repair applications , particularly as stents and stent coating .

a process for preparing polyvinylbutyral sheet having a desired uniform adhesivity comprising preparing a blend of polyvinylbutyral and a compatible quantity of a at least one plasticizer and an adhesion control agent , and extruding the blend to form a sheet , the improvement comprising monitoring the acidity of the sheet and adding water to the blend as an agent for controlling the adhesivity of said sheet .

a non - releasable mechanical join useful for permanent joins of plastics material cartons is formed by a row of a plurality of engagement tabs interlocked in a complementary row of slots . the engagement tabs have heads able to pass through the slots in one direction but unable to return in the other direction . the tab heads may be formed as arrowheads , the barbs of which act against edges of the slots are convexly arcuate towards the approaching arrowheads . this may help to provide secure engagement . the greater number of tabs and slots , the greater may be the permanence of the join .

bioprosthetic devices include an exterior biological tissue member which at least partly defines a cavity , and a proteinaceous biopolymer which fills the cavity , and intercalates and is chemically bound to the tissue of the surrounding biological tissue member . in preferred forms . the bioprosthetic device is a bioprosthetic vertebral disc having a fibrillar outer annulus which surrounds and defines an interior cavity and is formed by removal of at least a substantial portion of the natural gelatinous core therefrom . the cavity defined by the fibrillar outer annulus may then be filled with a flowable proteinaceous biopolymer . preferably , the proteinaceous biopolymer is a liquid mixture comprised of human or animal - derived protein material and a di - or polyaldehyde , which are allowed to react in situ to form a cross - linked biopolymer within the cavity . the liquid mixture may be formed in advance of being introduced into the cavity , or may be formed simultaneously during introduction into the cavity .

this invention relates to printable high strength / toughness polymerizable material systems for making dental products such as artificial teeth , dentures , splints , veneers , inlays , onlays , orthodontic appliances , aligners , copings , frame patterns , crowns and bridges and the like . a dlp , stereolithography , modified or their modification and combination based printer is used to cure polymerizable material in several different methods of this invention to build - up the object . the resulting three - dimensional object has good dimensional stability .

in a process for making a porous drainage medium composed of entangled strands of thermoplastic resin , subsequent to forming a tubular preform , the preform is formed with necked - down sections at intervals along the length thereof before proceeding to a cooling tank . as such , the drainage medium can be flexed in the cooling tank and can be discharged continuously and conveniently out of the cooling tank without being cut .

the invention provides a cyclomonomer having actin - binding activity . the cyclomonomer is of utility for the study of the molecular biology of actin polymerization . the cyclomonomer is also useful for the study of and treatment of the toxic effects of amanita sp . poisoning .

degradable polyimides are prepared in high yield by polymerizing a monomer containing at least two anhydride groups , and a monomer containing at least two primary amine groups and at least one acidic group , in bulk or in a solvent . the polyimides are very strong in terms of their mechanical properties , yet degradable under standard physiological conditions .