POLYMERIZATION BEHAVIOR OF 2,2,6,6-TETRAMETHYLPIPERIDINYL METHACRYLAE - A MONOMER CARRYING A HINDERED AMINE GROUP

Copolymers of 2,2,6,6-tetramethylpiperidinyl methacrylate (TPMA) with styrene (S) and with methyl methacrylate (MMA) were synthesized using AIBN as initiator. S-TPMA copolymers from feed ranging from 0.10-0.80 mole fractions TPMA and MMA-TPMA copolymers from feed of 0.04-0.85 mole fractions TPMA were used in the determination of monomer reactivity ratios r1, r2. Four different methods were employed in the calculations of r1 and r2 and all calculated results were in good agreement with each other. The structure of S-TPMA copolymers was inferred to be of an alternating nature while that of MMA-TPMA copolymers was random. Both copolymers are potential hindered amine light stabilizers (HALS) and are expected to be less extractable from, and more compatible with, polystyrene and poly(methyl methacrylate) base polymers.