Abstract In order to promote the degradation of PLA in seawater, a series of seawater-degradable polyester blends PVA/PLA were prepared by blending biodegradable polylactic acid (PLA) with water-soluble modified polyvinyl alcohol (PVA) in this paper. ADR 4370S was introduced to bring a certain degree of improvement in compatibility of PVA/PLA blends. The results of degradation test in natural seawater for 180 days show that the weight loss of PVA/PLA blends in seawater is much higher compared with that of pure PLA. PVA can be used as an effective hydrolysis accelerator for PLA matrix, helping to significantly reduce the molecular weight of PLA. The channels caused by dissolution/swelling of PVA facilitate the entry of water and microorganisms into the materials to contact with PLA, thereby promoting the degradation process of PLA matrix itself. Thus, both dissolution/swelling of PVA and degradation of PLA occur in PVA/PLA blends, and the degree of rapid dissolution of PVA in the early stage determines the degree of degradation of PLA. Graphical abstract

中文翻译：

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水溶性 PVA 加速 PLA 的海水降解

摘要 为了促进PLA在海水中的降解，本文将可生物降解的聚乳酸（PLA）与水溶性改性聚乙烯醇（PVA）共混，制备了一系列可海水降解的聚酯共混物PVA/PLA。引入 ADR 4370S 是为了在 PVA/PLA 共混物的相容性方面带来一定程度的改进。在天然海水中降解 180 天的结果表明，与纯 PLA 相比，PVA/PLA 共混物在海水中的失重要高得多。PVA 可作为 PLA 基质的有效水解促进剂，有助于显着降低 PLA 的分子量。PVA 溶解/溶胀引起的通道促进水和微生物进入材料与 PLA 接触，从而促进 PLA 基质本身的降解过程。因此，PVA/PLA共混物同时发生PVA的溶解/溶胀和PLA的降解，早期PVA快速溶解的程度决定了PLA的降解程度。图形概要