OPTICALLY-ACTIVE POLYMERS .2. COPOLYMERIZATION OF LIMONENE WITH MALEIC-ANHYDRIDE

Copolymerization of maleic anhydride (MA) and (R),(S)-limonene (LIM) w as studied in various solvents, using 2,2'-azoisobutyronitrile (AIBN) and benzoyl peroxide (BPO) as initiators and radiation (Co-60 gamma-so urce) within the temperature range of 20-70-degrees-C. Regardless of c onversion or initial comonomer feed ratios, the composition of LIM-MA copolymers ranged from about 1:1 to 1:1,6 and was dependent on the rea ction conditions, leading to a formation of materials with diverse sol ubilities, degrees of crosslinking and molecular weights. The main pro duct consists of a 1:1 LIM-MA copolymer with pendant 4-methyl-3-cycloh exenyl residues. At higher conversion these alicyclic unsaturations le ad to crosslinking. No reference to cyclocopolymerization was detected .