Graft Polymerization of Acrylic Acid onto Polypropylene Film: Immobilization of Chitosan Nanoparticles onto Grafted Films

Abstract

In this paper the aim is to immobilize chitosan nanoparticles on the surface of the polypropylene film, aqueous phase thermal decomposition characteristics of ammonium persulfate is used. The PP film is first hydroxylation pretreated in the protection of the high-purity nitrogen. And then ceric ammonium nitrate acting as an initiator, induce graft polymerization of acrylic acid on the hydroxylated treated PP film. Thus, carboxyl functional groups are grafted on the surface of PP film. Finally chitason namoparticles are fixed on PP film by the reaction of carboxyl group and the amino group of chitosan. Experimental results show that: when the reaction temperature is 60 ° C, the concentration of acrylic acid is 8% (w/w), the reaction time reaches 4h, the concentration of ceric ammonium nitrate is 2mM, the optimum grafting ratio is obtained, which is up to 0.6008×10-7mol/cm2. Total reflection Fourier transform infrared spectroscopy absorption peaks appear at 1712cm-1, indicating that the-COOH has been successfully grafted to the film surface; the SEM scanning the film surface shows that the chitosan nanoparticles were perfectly immobilized on the modified film. Key words: Acrylic acid, Polypropylene film, Chitosan nanoparticles, Graft polymerization