Investigation of antioxidant performance in different polymer matrices of various phosphorus compounds

Oxidation process is a very powerful chemical reaction presence of heat, light, oxygen and pressure that produce harmful free radicals can damage to the cells in living organism or the chains and can deterioration physical, mechanical and chemical properties in all polymer matrices. Therefore, polymer oxidation problems are being encountered frequently in polymer industry. Low density polyethylene (LDPE) and acrylonitrile butadiene styrene (ABS) terpolymer are the raw materials which used in relatively high amounts in the plastic industry. However, with the increasing trend for using natural recources, it is increasing the use of natural sourced Poly(lactic asit). Polylactic acid (PLA) is often used in conjunction with technological advances in recent years, and it is the preferred polymer due to its biocompatibility in biomedical applications. Life times of LDPE, ABS, and PLA decreases under oxidation effect like other polymers. Polylactic acid (PLA) is a commonly used material in polymer applications recent years. In order to prevent of devastating effect of oxidation reactions, antioxidants were performed a very important role in both living organisms and polymers. Antioxidants can scavenge free radicals by donating electrons to them and changing harmless forms. Hence antioxidants are widely used both in dietary supplements for humans and in additives for polymers. Studies on more effective, economic and bio-based antioxidants were drew interest due to provide desired effects. In this study lab-synthesized various phosphorous compounds and bio-based compounds were investigated as antioxidant. Different commercial type of antioxidants were also used for comparison of performances in polymers. Preparation of samples were achieved by using co-rotating intermeshing twin screw extruder (16 mm, L/D ratio:35) under constant suitable rate at suitable temperature profile according to melting and degradation points of polymers. Antioxidant performances of all compounds were evaluated by determination of oxygen induction times (OIT) of obtained homogenous, well mixed samples with DSC equipment. Mechanical test such as tensile strenght and elongation test were also performed in order to expose of effects of antioxidant additives to mechanical properties.