Plasma assisted sericin-g-PLA clay aerogel with acrylic acid

Abstract

Clay aerogel is light weight, low density and high porosity material produced from bentonite via freeze-drying technique which the morphology is suitable for several applications including biodegradable absorbent material. In this study, sericin-g-PLA clay aerogel wiyh acrylic acid, the new material to use as ethylene adsorption material, was prosperously prepared. Silk sericin, the glue-like protein from silk cocoon, is interested in the ability to adsorb the ethylene gas due to its high amino groups. Silk sericin was extracted from 4 species of traditional Thai silk cocoon; Nang Noi, Nang Lai, Dok Bua and Luang Pairote. To over the fragile problem of the clay aerogel, the incorporation of clay with polymeric material is required. Lactide monomer was employed to improve the mechanical properties via grafting with sericin in bulk polymerization. Moreover, acrylic acid was used as a cross-linking agent that initiated the reaction by plasma treatment. The aim of this study was to prepared sericin-g-PLA clay aerogel by freeze-drying technique using acrylic acid as cross-linked agent and studied the influence of acrylic acid, clay contents, plasma treatment time and mass ratios of silk sericin and LA monomer to the properties of the aerogel. The mechanical properties were improved by increasing acrylic acid and clay loading. Increasing of acrylic acid content, was improved the thermal properties of the aerogels. Plasma treatment time at 30 s was highly enhanced the thermal and mechanical properties of the aerogels. In contrast, the increasing of clay content strongly reduced the thermal stability. The increase of silk sericin content in sericin-g-PLA powerfully increased ethylene adsorption ability.