The molecular structure control of butyl methacrylate/acrylamide (co)polymers

Abstract

Butyl methacrylate (BMA)/acrylamide (AM) (co)polymers were synthesized through free radical bulk copolymerization by two steps. Effect of synthesis process on the molecular structure and properties of BMA/AM (co)polymers was deeply investigated. 13C NMR results indicated that AM only participated in copolymerization with BMA, which would be promoted under a higher prepolymerization temperature. A higher conversion ratio of AM could be obtained by batch feeding. FTIR results showed that a higher prepolymerization temperature or batch feeding could increase the content of AM unit in the BMA/AM (co)polymers. DMA results indicated that a higher prepolymerization temperature or batch feeding would induce a higher Tg value of the BMA/AM (co)polymer. DSC and TGA results showed a weight loss at 150–250°C because of the imidization reactions, which would be increased by a higher prepolymerization temperature or batch feeding. Mechanical properties of PMI foam would increase under a higher prepolymerization temperature or batch feeding. In a word, the molecular structure and properties of the BMA/AM (co)polymers could be controlled.