Water Absorption Characteristics of Successive Alkali Treated Jute/Polylactic Acid Composites

Abstract

Hydrolytic degradation of polylactic acid composites incorporated with untreated (UTJ/PLA) and successive alkali treated short jute fiber at different concentrations of alkali (5STJ/PLA, 10STJ/PLA and 15STJ/PLA) with varying fiber weight fractions due to water absorptions were investigated at 23°C. The results revealed that the steadiness of UTJ/PLA and STJ/PLA composites in water depend less on jute fiber content and it is significantly influenced by fiber treatment. The water uptake of plain PLA after 30days was 0.97%, evidencing the hydrophobicity of neat PLA. From the results, it is depicted that the water uptake quantity rised in all types of composites with increase in the jute fiber fraction. The maximum water uptake of 10.82% was seen after 30days for composite with 25% of raw jute fiber. Further, the percentage of water absorption reduces in the composite with increasing NaOH percentage for treating the jute fibers. The amount of water absorption is 6.59, 5.73, and 4.60% for composites with 25% of treated fiber with 5%, 10%, and 15% of sodium hydroxide concentration followed by bleaching with H2O2, respectively. The Fickian behavior is observed in plain PLA and its composite with untreated and alkali treated jute fiber at 5 and 10% concentrations of NaOH in the treatment. But in case of PLA composite with successive alkali treated fiber at 15% NaOH concentration, there is a deviation in the Fickian behavior because higher concentrations of alkali in the treatment may lead oxidative damage to the fiber.