Chemically circular, mechanically tough, and melt-processable polyhydroxyalkanoates

• 成果类型: Article
• 署名作者: Zhou, Li; Zhang, Zhen; Shi, Changxia; Scoti, Miriam; Barange, Deepak K.; Gowda, Ravikumar R.; Chen, Eugene Y. -X.
• 署名单位: Colorado State University System; Colorado State University Fort Collins; University of Naples Federico II
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-11311
• DOI: 10.1126/science.adg4520
• 发表日期: 2023-04-07
• 页码: 64-69
• 关键词: beta-butyrolactone; zinc catalysts; polymerization; ACID; plastics

摘要

Polyhydroxyalkanoates (PHAs) have attracted increasing interest as sustainable plastics because of their biorenewability and biodegradability in the ambient environment. However, current semicrystalline PHAs face three long-standing challenges to broad commercial implementation and application: lack of melt processability, mechanical brittleness, and unrealized recyclability, the last of which is essential for achieving a circular plastics economy. Here we report a synthetic PHA platform that addresses the origin of thermal instability by eliminating a-hydrogens in the PHA repeat units and thus precluding facile cis-elimination during thermal degradation. This simple a,a-disubstitution in PHAs enhances the thermal stability so substantially that the PHAs become melt-processable. Synergistically, this structural modification also endows the PHAs with the mechanical toughness, intrinsic crystallinity, and closed-loop chemical recyclability.