Polymerization of monomers and oligomers with double bonds

3 POLYMERIZATION OF MONOMERS AND OLIGOMERS WITH DOUBLE BONDS 

Monomers containing double bonds, which can be transformed into massive items by free radical polymerization, are widely used. 

Vinyl monomers are important members of this group of products, particularly, methyl and butyl methacrylates, which polymerize into useful thermoplastic materials poly(methyl methacrylate) (PMMA) [-CH2-C(CH3)(COOCH3)-]n 

Mixtures of methyl methacrylate and methacrylic acid or butyl methacrylate are also used. Polymer-monomer mixtures are often used in the production process. This allows reduction of the total exothermic effect of the process, shrinkage, and production time. These mixtures are obtained by two methods  

Organic peroxides acyl peroxides (benzoyl, acetyl, lauryl peroxides, etc), alkyl peroxides, hydroperoxides, etc. are used as polymerization initiators. Azocompounds (for example, x,a -a-zobis(isobutyronitrile), initiator mixtures, redox systems, etc. are also widely used as initiators. In 

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