Water-soluble cationic quaternary ammonium monomers
The present application is a division of U.S. Ser. No. 621,338, filed June 15, 1984, now U.S. Pat. No. 4,656,277. 
    
    
     THE INVENTION 
     The present invention is concerned with the methyl chloride or dimethyl sulfate quaternary ammonium salts of 1-methacryloyl-4-methyl piperazine. It is also directed to the homopolymers as well as the acrylamide copolymers of these novel monomers. 
     The starting vinyl monomer used to prepare the ammonium salts is 1-methacryloyl-4-methyl piperazine. This monomer is reacted with appropriate amounts of methyl chloride or dimethyl sulfate to produce the compounds of the invention. To prepare the starting materials, acryloyl chloride is reacted with N-methylpiperazine. 
     The monomers may be either homopolymerized or may be copolymerized with other vinyl addition monomers capable of being polymerized with the monomers of this invention. The resultant homopolymers will be water-soluble. Copolymers may be either water-soluble or water insoluble. A particularly useful water-soluble copolymer may be prepared by polymerizing the monomers of this invention with acrylamide. Homopolymers and copolymers of the monomers of this invention with acrylamide have a variety of industrial uses such as, for example flocculants and dewatering agents. 
     The monomers of this invention may be copolymerized with either water-soluble or water-insoluble vinyl addition monomers having suitable reactivity ratios. The co-monomers may be either nonionic, cationic, or anionic. Examples of suitable non-ionic monomers include: acrylamide, methacrylamide, acrylonitrile, vinyl acetate, lower alkyl acrylates, lower alkyl methacrylates, lower alkyl ethacrylates, styrene, etc. Examples of suitable anionic co-monomers useful in this invention include: acrylic acid, methacrylic acid, itaconic acid, maleic anhydride, acrylamidomethylpropanesulfonic acid, etc. Examples of suitable cationic monomers which may be useful in this invention include: dimethylaminoethylacrylate, quaternary salts of dimethylaminoethylacrylate, dimethylaminoethylmethacrylate, dimethylaminoethylmethacrylate quaternaries, diallyldimethylammonium chloride, methacrylamidopropyltrimethylammonium chloride, N-vinyl pyrrolidone, vinyl pyridine, N,N-dimethylaminomethylacrylamide, N,N-dimethylaminomethylmethacrylamide, N,N-dimethylaminomethylacrylamide quaternaries, etc. 
     All that is important is that the co-monomer be capable of polymerizing, or have suitable reactivity ratios, with the monomers of this invention. Generally when copolymerized such copolymers will contain from 1-99 mole percent, preferably 1-70 mole percent and most preferably 2-50 mole percent of the comonomer or comonomers employed. 
     The polymers and copolymers of the invention can be prepared either using conventional solution polymerization techniques or the so-called inverse emulsion polymerization method which utilizes polymerization of water-soluble vinyl monomers in the form of water-in-oil emulsions. This technique is described in Vanderhoff, U.S. Pat. No. 3,284,393, the disclosure of which is incorporated herein by reference. 
    
    
     EXAMPLES 
     To illustrate the invention, the following are given by way of example: 
     Example 1 
     Synthesis of 1-methacrylol-4-methyl piperazine 
     Methacryloyl chloride (102 g) in methylene chloride (100 ml) was added into a methylene chloride (450 ml) solution of N-methyl piperazine (86 g) over a period of one hour. The reaction temperature was kept below 25° C. with cooling. After the addition was completed, the reaction mixture was stirred at ambient temperature for two hours. Then, sodium carbonate (46 g) in water (215 g) was added into the reaction mixture with stirring. A crude product of 1-methacryloyl-4-methyl piperazine (100 g) was recovered from the methylene chloride solution. The product was distilled and the fraction collected at 74°-78° C./5 mm Hg was characterized by I.R. and C13 NMR. 
     Example 2 
     Quaternization of 1-methacryloyl-4-methyl piperazine 
     23.2 g. dimethyl sulfate was added slowly into 30 g. 1-methacryloyl-4-methyl piperazine in 51.8 g. water with cooling so that the reaction temperature was kept below 30° C. After the addition was completed, the reaction mixture was stirred at ambient temperature for two hours. The product was characterized by C13 NMR. 
     Into a 300 ml Parr bomb was charged 26.6 g. water, 21 g. 1-methacryloyl-4-methyl piperazine, and 10 g. methyl chloride. The valves were closed and the bomb was heated to and maintained at 60° C. for 21/2 hours. The product was characterized by C13 NMR. 
     Example 3 
     
         ______________________________________                                    
Water-in-Oil Emulsion Polymerization                                      
of Acrylamide and MAMPIPQUAT                                              
______________________________________                                    
Oil Phase:                                                                
LOPS               130.0       g                                          
Sorbitan Monooleate                                                       
                   7.5         g                                          
4 moles EO reacted 2.5         g                                          
with Sorbitan Monostearate                                                
Aqueous Phase:                                                            
50% MAMPIP MSQ.sup.1                                                      
                   51.25       g                                          
46.4% Acrylamide solution                                                 
                   246.49      g                                          
H.sub.2 O          59.92       g                                          
Versene            .05         g                                          
Initiator:                                                                
2,2&#39;-Azobisisobutyronitrile                                               
                   .28         g                                          
______________________________________                                    
 
    
     The oil and the aqueous phases (pH 5) were first prepared and the emulsion was obtained by adding the aqueous solution into the LOPS solution with vigorous stirring. 
     The emulsion was purged with nitrogen for 1/2 hour and then heated to 45° C. The initiator was added. The reaction was maintained at 45° C. for four hours and at 65° C. for one hour. The reaction was stopped and cooled to room temperature. G.C. analysis of the residual monomer shows the polymerization was 74% complete. IV of the copolymer was 7.0. 
     The above quaternary ammonium salt monomers may be polymerized either by way of solution or by way of the so-called &#34;water-in-oil&#34; emulsion technique, which process is described in detail in Vanderhoff, U.S. Pat. No. 3,284,393. 
     Polymers produced using these quaternary ammonium salt monomers are useful as flocculating and dewatering agents.