2002 Volume 59 Issue 4 Pages 212-217
The polymerization of methyl methacrylate (MMA) with diisocyanate-Cu (acac) 2 complexes prepared from alicyclic diisocyanates, 2, 5 (2, 6) -bis (isocyanatomethyl) bicyclo [2. 2. 1] heptane (NBDI), 1, 3-bis (isocyanatomethyl) cyclohexane (H6XDI), and 3-isocyanatomethy1-3, 5, 5trimethylcyclohexylisocyanate (IPDI), and copper acethylacetonate was investigated. When polymerizations catalyzed by diisocyanate-Cu (acac) 2 complexes were carried out for 24h at 60°C in THF, IPDI-Cu (acac) 2 complex showed high activity and the narrow molecular distribution (Mw /Mn=1.26), and the number average molecular weight (Mn) of the resulting polymer was 971000. From a kinetic study using the copper complex, the polymerization rate (Rp) can be expressed as Rp=k [MMA] 2.3 [IPDI-Cu (acac) 2] 0.44. The overall activation energy of the polymerization was determined to be 42.5kJ / mol. In the case of IPDI-Cu (acac) 2 complex, the resulting polymers were somewhat rich in isotactic structure.
