Polyfmethyl methacrylate radical

The influence of solvents on the microstructure of polymer was investigated in the free radical polymerization of methyl methacrylate for the first time by Fox et al. in 196279. The stereochemical structure of the polymer prepared at 60 °C was, within the precision of the data, independent of the solvent used and did not measurably differ from that of the polymers obtained in bulk polymerization at the same temperature. Watanabe et al.80 demonstrated that the temperature dependence of the microtacticity of polyfmethyl methacrylate) varied with solvents and concluded that the temperature dependence was mainly caused by the polymer-solvent interaction. 

Chain branching is a common occurrence during radical polymeriza-B tions and is not restricted to polyethylene. Polypropylene, polystyrene, andl polyfmethyl methacrylate) all contain branched chains. Studies have shown 1 that short-chain branching occurs about 50 times as often as long-chain branching. J... 

Trithiocarbonates (TTC) also offer an interesting alternative platform by dynamic covalent reshuffling reactions of TTC via a free radical mechanism shown in Fig. 15b. It was first introduced into polyfmethyl methacrylate) (PMMA) and polystyrene (PS) gels as a covalent crosslinker, which exhibited dynamic properties [64]. Following this, it was found that the C-S braids of TTC can be photostimulated, and high segmental mobdity of the polymer matrix obtained by RAFT copolymerization of -butyl acrylate (BA) and a TTC crosslinker can facilitate repetitive network repairs using UV radiation at 330 nm [64]. 

We have studied the degradation by high-energy radiation of a number of families of polymers by using a variety of techniques, including ESR spectroscopy [10,11]. In this paper we show the similarities and differences in the role of free radicals in the radiolysis of polyfmethyl methacrylate), polystyrene, and random copolymers of methyl methacrylate and styrene. 

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