Compatibility Estimation of Oligobutadienediol with Simple Oligoetherpolyols for Molded Polyurethane Compositions Development
This article includes the results of compatibility of oligomeric hydroxyl-containing butadienerubber with oligoetherpolyols on the basis of propylene oxide (Laprols). The compatibility limits of liquid hydroxyl-containing butadiene rubber of Krasol LBH-3000V brand with polypropyleneglycols of Laprol brand with different molecular weights were determined.
Composites of Reduced Flammability Based on Amorphous Elastic Polyurethane and Halogen-containing Flame Retardant
The effect of a mixture of halogen-containing fl ame retardants based on chloroparaffins and 1,1,9-trihydroperfl uorononanol-1 immobilized on a montmorillonite carrier on the character of reducing the fl ammability of polyurethane was studied. Using X-ray diffraction and sol-gel analysis, the structural and morphological features of the elastomers obtained were studied. It has been revealed that intercalation of macromolecular chains of a matrix amorphous polymer into the intralayer spaces of a fl uorine-containing organoclay occurs with an increase in a degree of structural perfection of the macromolecular system that contributes to an increase in the fire resistance of the resulting polyurethane composites.
Determination of iodide with 1,3-dibromo-5,5-dimethylhydantoin (DBH) in comparison with the ICl-method. Analytical methods of pharmacopeias with DBH in respect to environmental and economical concern. Part 3.
USP 1995 (The United States Pharmacopeia, 23rd Edit., (1995), potassium iodide p. 1265, sodium iodide p. 1424), PH. EUR. 1997 (European Pharmacopoeia, third ed., Council of Europe, Strasbourg, (1997), potassium iodide p. 1367, sodium iodide p. 1493) and JAP 1996 (The Japanes Pharmacopoeia, 13th ed. (1996), potassium iodide p. 578, sodium iodide p. 630) determine iodide with the ICl-method (J. Am. Chem. Soc. 25 (1903) 756-761; Z. Anorg. Chem. 36 (1903) 76-83; Fresenius Z. Anal. Chem. 106 (1936) 12-23; Arzneibuch-Kommentar, Wissenschaftliche Erläuterungen zum Europäischen Arzneibuch, Wissenschaftliche Verlagsgesellschaft mbH, Stuttgart, Govi-Verlag - Pharmazeutischer Verlag GmbH, Eschborn, 12th suppl. (1999), K10 p. 2), using chloroform, which is toxic and hazardous to environment. Without the application of chlorinated hydrocarbons USP 2000 (The United State Pharmacopeia, 24th ed. (2000), potassium iodide p. 1368, sodium iodide p. 1535) and Brit 1999 (British Pharmacopoeia London, (1999), Appendix VIII C, p. A162) titrate iodide with the redox indicator amaranth. A titration with potentiometric indication giving two end-points at the step of I(2) and [ICl(2)](-) is described. Due to the high concentration of hydrochloric acid required for the ICl-method, the determination with DBH (1,3-dibromo-5,5-dimethylhydantoin; 1,3-dibromo-5,5-dimethyl-2,4-imidazolidinedione) can be recommended and is performed easily. Similarly, the iodide content of gallamine triethiodide may be analyzed with DBH by application of a visual two-phase titration in water and ethyl acetate or with potentiometric indication in a mixture of 2-propanol and water. During the removal of the excess of DBH 4-bromo-triethylgallamine (2,2',2"-[1-bromo-benzene-2,3,4-triyltris(oxy)]N,N,N-triethylethanium) is formed.