Plastisisation of polyvinilchloride biofilms with palm oil oleine and methylmethacrylate as comonomer

Abstract

Polyvinylchloride (PVC) is the second largest thermoplastics produced after polyethylene (PE), polypropylene (PP) and polystyrene (PS), especially for packaging, households, toys, and other commodity products. However when used for food packaging, PVC has to be plastisised using plastisisers (added upto 30%), which may not comply with safety requirements for food biofilms. Palm oil oleine (POO) is a nontoxic and edible triglyceride containing double bond and can be bounded onto PVC backbone in the presence of methylmethacrylate (MMA) as comonomer and benzylperoxide (BPO) as initiator. The PVC resin was dissolved in tetrahydrofurane (THF), added with POO, MMA and BPO, (in various compositions), under constant stirring in a reflux reactor. The reaction mixtures were then refluxed for 3 hours under nitrogen atmosphere at constant pressure 1 atm. Plastisised PVC films were obtained after casting the reaction mixtures on a glass plates, and dried under vacuum at constant temperature 40°C. Mechanical properties of the films were tested and their morphology were analysed under scanning electron microscope (SEM) and FTIR spectoscopy. Optimum clear and flexible PVC films was obtained when weight composition of the reaction mixture: PVC/MMA/POO/BPO: 2/0.5/0.5/0.35. Elongation at break of the optimum film was more than 95% higher, whereas the tensile strength was 60% lower when compare to those of pure casted PVC film. SEM analysis of the film surface also showed good homogenous morphology, whereas analysis of FTIR spectra of the films before and after exhausted washing in n-hexane, indicating 48.5% binding of MMA and POO in the PVC films.