Copolymerisation behaviour of methyl methacrylate with 2-methyl-acrylic acid 2-(3-phenyl-acryloyloxy)-ethyl ester

摘要

Copolymerisation of methyl methacrylate (MMA) with varying mole fractions of 2-methyl-acrylic acid 2-(3-phenyl-acryloyloxy)-ethyl ester (B) [i.e.in the range of 0.1- 0.5 in the initial feed] was carried out at 60 deg C in bulk using azobisisobutyronitrile (AIBN) as an initiator.The copolymer composition was determined from ~1H-NMR by taking the ratio of proton resonance signals due to -OCH_3 of MMA (5=3.59ppm) and -OCH_2CH_2,O-/C_6H_5CH=CH of B (delta=4.367 6.48 ppm).Copolymerisations were terminated at low conversion (in the range of 10-15%) and the reactivity ratios were calculated using Finemann Ross and Kelen Tudos methods.Reactivity ratios for both the monomers were higher than unity.Thermal characterisation of the copolymers was done by using differential scanning calorimetry and thermogravimetric analysis.Fabrication of sheets was carried out by casting prepolymer syrup having very low mole fractions (approx2-10 mole %) of comonomer (B).The effect of incorporation of comonomer on the physical and mechanical properties of PMMA has also been evaluated.