Synthesis And Properties Of Chlorinated Polypropylene Grafted Acrylate

Biaxially oriented polypropylene(BOPP)film,with excellent strength,transparency and glossiness,is a very promising material in packaging industry.However,BOPP film is extremely difficult to be printed due to its high crystallinity,low surface energy and the absence of reactive groups.Several surface treatment approaches have been carried out to overcome the problem,such as corona treatment,flame treatment and plasma treatment.Nonetheless,there is noticeable degradation effect for them,resulting in insufficient product reliability.Therefore,this paper aimed at developing a polymeric coating that can reliably promote the surface performance of BOPP film.The coating should be prepared via applying modified emulsion on BOPP film,it was expected to have excellent adhesion to the film and promote the printability of BOPP film.Meanwhile,it is necessary to reduce the content of VOC in emulsion for environmental friendliness.In this paper,methyl methacrylate(MMA),butyl acrylate(BA)and acrylic acid(AA)were grafted onto CPP backbone using BPO as initiator and using butyl acetate as solvent.The influencing factors and their influence degrees on graft reaction were systematically investigated.In addition,the optimum condition of graft reaction was determined by orthogonal experiments.Phase inversion was conducted to obtain waterborne emulsion using sodium dodecyl sulfate(SDS)as emulsifier.The effects of parameters on phase inversion were studied.The content of VOC in the emulsion was decreased by using vacuum distillation.IR?DSC?TG were used to characterize the performance of grafted product.Printing experiment was performed to explore the coating's application value in packaging and printing industry.The results showed that the optimum prescription and condition were as follows: in graft process,?(BPO)was 1%,?(acrylate monomers)was 45%,reaction temperature was 95 ?,reaction time was 4.5 h,and in phase inversion process,temperature was 65 ?,emulsifier concentration was 5%.In the optimum condition,the grafting ratio was 10.53%,the waterborne emulsion obtained was stable and the average diameter of particles was 0.19 ?m,the adhesion of coating based on the emulsion was level 0.Compared with CPP,CPP grafted acrylate had better miscibility with polyacrylate and had enhanced thermal performance.The waterborne coating obtained in the optimum condition had excellent thermal performance,optical performance,mechanical performance,etc.It can apparently improve the printing quality of BOPP film and BOPP corona surface,which meet the requirements of practical application in the field of packaging.