Poly(lactic acid)/halloysite nanoclay (PLA/HNC) nanocomposites with N,N′-ethylenebis(stearamide) (EBS) were produced by melt mixing. Water absorption behaviors of the PLA nanocomposites were studied at three different temperatures, that is, 30, 40, and 50°C. The water absorption kinetics of PLA/HNC nanocomposites conform to Fickian diffusion behavior at immersion temperatures of 30 and 40°C due to the diffusional exponent (n) values that were close to 0.5 for all specimens. However, the hydrolysis of PLA occurred for longer time deviations at 50°C. Activation energy of water diffusion (Ea) for PLA nanocomposites were found to be affected by the HNC and EBS contents. The glass transition temperature (Tg), cold crystallization temperature (Tcc), and melting temperature (Tm) of the PLA sample were shifted to lower temperature after subjected to immersion temperature of 50°C. The carbonyl index of all PLA specimens increased after water absorption at 40 and 50°C due to the formation of higher amount of carboxylic acid end groups during the hydrolysis process.
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