Copolymerization of 2-Hydtoxypropyl Methacrylate with Alkyl Methacrylates

2-Hydroxypropyl methacrylate (2 HPMA) has been copolym-erized with ethyl methacrylate (EMA), n-butyl methacrylate (BMA), and 2-ethylhexyl methacrylate (EHMA) in bulk at 60°C using benzoyl peroxide as initiator. The copolymer composition has been determined from the hydroxyl content. The reactivity ratios have been calculated by the YBR method. For copolymerization of 2-HPMA (M₁) with EMA (M₂), the reactivity ratios are: r₁=1.807 ± 0.032, r₂=0.245 ± 0.021; with BMA (M₂) they are r₁=2.378 ± 0.001, r₂=0.19 ± 0.01; and with EHMA the values are r₁=4.370 ± 0.048, r₂=0.103 ± 0.006. Since the reactivity ratios are the measure of distribution of monomer units in a copolymer chain, the values obtained are compared and discussed. This enables us to choose a suitable copolymer for synthesizing thermoset acrylic polymers, which are obtained from cross-linking of hydroxy functional groups of HPMA units, for specific end uses.