Abstract

AbstractPoly(lactic acid) (PLA) and its blends with starch and methylenediphenyl diisocyanate (MDI) were extruded in a twin‐screw extruder and compress‐molded in a dog‐bone shaped tensile bars to form test specimens. The thermalgravimetric profile and thermal endurance of these samples were characterized. The effect of physical aging on mechanical and thermal properties of these samples was evaluated. For the aging study, samples were stored at 25°C and relative humidity fluctuating between 90 and 30%, from 2 to 180 days, with or without a polyethylene bag as a moisture barrier. Physical aging of pure PLA samples stored in a controlled environment from 2 to 360 days was also evaluated. The presence of MDI in the PLA/starch composite did not affect the thermal decomposition profile. The PLA showed the highest Arrhenius activation energy and strongest thermal endurance of all samples, followed by PLA/starch/MDI and PLA/starch. Exposure of the samples to storage conditions with fluctuating relative humidity (RH) significantly affects thermal‐mechanical performance of PLA and its composites. But, the samples stored in plastic bags can minimize such effects. Mechanical properties of PLA and PLA/starch‐based composites sealed in plastic bags had no significant change during 30‐day storage in fluctuating humidity conditions (30–90% RH). POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.