A facile method for grafting polymerisation of acrylonitrile onto LDPE film with high grafting efficiency

A facile and effective surface grafting polymerisation method was designed and investigated to graft acrylonitrile (AN) onto low-density polyethylene (LDPE) film using benzoyl peroxide (BPO) as an initiator. This method consisted of two steps. In the first step, BPO was adsorbed on the surface of LDPE film by immersing LDPE film in BPO solution; in the second step, grafting polymerisation of AN onto LDPE film was carried out under heat. Because the grafting polymerisation was carried out with AN in vapour phase and the concentration of AN was very low, the homopolymerisation of AN could be effectively suppressed and therefore the grafting efficiency was very high (approaching 100%). Grafting percent (Gp) could be controlled from 0 to 118% by adjusting reaction conditions in the first step and/or in the second step respectively. A possible model was proposed to interpret the experimental results.