Effect of chain extenders on thermal and mechanical properties of poly(lactic acid) at high processing temperatures: Potential application in PLA/Polyamide 6 blend

摘要: Abstract Poly(lactic acid) (PLA) is vulnerable to severe thermal degradation when it was processed at high temperature, especially above 200 °C. An undesired molecular weight reduction and loss caused by both hydrolysis depolymerization reactions result in poor mechanical performance of final products. Thus, the aim this work study effect chain extenders on properties PLA temperatures a twin screw extruder having four different sets temperature profiles. Two types extenders, multifunctional epoxide (ECE) polycarbodiimide (PCD) were used with constant amount 0.5 phr. All samples characterized using GPC, MFI, DSC, TGA, FT-IR tensile impact tester. The GPC results showed that (Mw) tended decrease increasing processing its distribution (MWD) shifted towards lower weights whereas Mw all added increased MWD exhibited bimodal slightly higher population. addition also improved elongation break strength. For samples, these decreased. TGA thermograms increase onset deflection compared ones. investigation based matrix (70%wt total polymer) performed blending Polyamide 6 (30%wt 0.5 phr ECE or PCD within profile 170–250 °C. blend proved ease without sacrificing properties. Both provided improvement modulus strength, strength for PLA/PA6/ECE blend. They 92.2% 65.1% respectively ECE.