Investigation of Role of both Nucleating Agent and Plasticizer on Physical, Mechanical and Thermal Properties of Poly(Lactic Acid)

The role of a kind of plasticizer (OLA8) and two types of nucleating agents (LAK301 and PDLA) on the physical, mechanical and thermal behaviors of poly-lactic acid (PLA) were studied by differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA) and tensile test. The results show that the OLA8 is an efficient plasticizer for PLA. this is because in the presence of 20wt% of OLA8 the elongation at break of PLA promoted. Also adding plasticizer to PLA causes to drop down both enthalpy and crystallinity unlike the presence of nucleating agent. For example the enthalpy and crystallization of a sample with composition of 20% OLA8-5%PDLA-2.8%LAK is half of than that of pure PLA. At constant plasticizer content, addition nucleating agents in different types and quantities causes to promote a little bit in enthalpy and crystallinity. in the presence of both plasticizer and nucleating agent (20%OLA8-5%PDLA-2.8%LAK) half time crystallization as 0.46″ min was recorded. In the same composition the glass transition temperature reduces 10˚C relation to pure PLA.