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Closely related to the regularity of its mechanical, optical, dielectric performance of polymer height regulated or highly isotactic polymer is easy to form the spiral form of the rich more performance characteristics, thus demonstrating the unique huge optical activity may in biological The field of medicine, asymmetric reactions, light materials valuable applications. The radical polymerization is the mainstream method to obtain a large molecular weight polymer, and easy on the polymer was subjected to a variety of structural modification in order to obtain the corresponding performance. The photoinitiated polymerization technology for its mild, efficient, environmentally friendly and operability characteristics of the concern and attention of more and more people in the polymerization reaction. Photopolymerization technology can achieve efficient radical polymerization under low temperature conditions, which is a polymer stereoregularity regulation facilitate. Proposed synthesized gentle, rapid photopolymerization means having a high stereoregularity of methyl methacrylate polymer, using the Low efficient photopolymerizable monomer itself asymmetry induced by the polar solvent, a transition metal salt of the subject asymmetric chelation technologies such as, regulatory formed to have a high degree of regularity of the polymer. With methyl methacrylate (MMA), the subject free radical polymerization reaction for the study, carried out of the reaction system at different temperatures of a series of radical photopolymerization reaction, and achieved the following research results. 1, MMA radical photopolymerization reaction than the thermal polymerization reaction resulting polymerization product stereoregularity, room temperature, Lewis acid trifluoromethanesulfonic acid, yttrium (Y (OTf) 3), trifluoromethanesulfonic acid ytterbium (Yb (OTf) 3 ), ZnBr2, L-() - tartaric acid, and hexamethylphosphoric triamide (HMPA), etc. to join the light of MMA radical polymerization product stereoregularity tacticity significant effect between the three units of the resulting polymerization product isotacticity slightly increased, but the three-unit isotacticity basically not changed. MMA Low radical photopolymerization reaction is carried out in common solvents to the polymerization yields were low, in some of the weakly polar solvent or not the polymerization product. Hexafluoroisopropanol as a solvent when the resultant polymer yield and tacticity were higher, -78 ° C as the solvent, HFIP, [MMA] = 4.35 mol / L, irradiation 5H, the polymerization yield was 14.8%, polymer r up to 95%. Lewis acid ZnBr2, Y (OTf) 3, Yb (OTf) 3, L-()-tartaric acid and HMPA role in the MMA cryogenic radical photopolymerization process, and the resulting polymerization product mm increased slightly but did not play a significant role. 3 to polyethylene glycol (such as PEG200, triethylene glycol, diethylene glycol), 1,2 - propylene glycol as a solvent, -60 ° C, MMA free radical polymerization carried out in the state of solidification of the reaction system, obtain The stereoregular polymer while a higher polymer yield can be obtained. Several polyethylene glycol as the solvent, the appropriate concentration of the monomers, irradiation 3H, the PMMA polymerization production rates above 60%, such a high polymerization yield is impossible to achieve under the same conditions in other solvents. The study found that has not been reported in the literature, this research innovations. Adding an appropriate amount of the multi-glycol system of HFIP to improve the polymerization product stereoregularity while also increase the polymerization yield.
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