Controlled radical polymerization of methyl methacrylate in the presence of CuX/phen complexes and alkyl halides

The polymerization behaviour of methyl methacrylate (MMA) in p-xylene in th e presence of CuCl/L [L = 1,10-phenanthroline (phen) or 4,7-diphenyl-1,10-p henanthroline (DPP)] and tetrachlorocarbon has been studied. For the CCl4/C uCl/phen/MMA/p-xylene system. the linear relationship between the number-av erage molecular weight of the resulting poly(methyl methacrylate) (PMMA) an d MMA conversion, as well as between In[M](0)/[M] and time, demonstrate the 'living' nature of this system. When phen is replaced by DPP the polymeriz ation becomes slower, but the molecular weight and molecular weight distrib ution are better controlled. The stereochemistry of PMMA synthesized in the CCl4/CuCl/DPP/MMA/p-xylene system indicates that the MMA monomer adds to t he living polymer chain end in an atactic fashion. (C) 1999 Elsevier Scienc e Ltd. All rights reserved.