高同选择性的rac-β-butyrolactone的环开聚合:获得具有聚烯类材料特性的合成聚烯3-基酸盐
Jonas Bruckmoser1, Stefanie Pongratz1, Lucas Stieglitz1
1Catalysis Research Center, Department of Chemistry, Technical University of Munich, 85748 Garching, Germany.
Journal of the American Chemical Society
|May 12, 2023
概括
研究人员开发了一种用于开环聚合的β-丁烯酸 (β-BL) 的新催化剂,产生具有高同位性聚3-基酸 (PHB),具有更好的材料特性和处理能力.
科学领域:
- 聚合物化学
- 有机金属催化
- 材料科学
背景情况:
- 聚3-酸 (PHB) 是一种可生物降解的聚,可作为聚烯的可持续替代品.
- 现有的PHB合成方法通常具有较低的立体选择性或有限的材料特性.
- 环开聚合 (ROP) 为合成立体规律PHB提供了一个受控的途径.
研究的目的:
- 开发一种高同选择性催化剂系统,用于赛米性β-丁酸盐 (β-BL) 的环开聚合.
- 合成具有增强材料性质的异氧化聚酸 (PHB).
- 研究化学合成PHB作为聚烯替代品的潜力.
主要方法:
- 基于Y[N(SiHMe2) 23(THF) 2和萨兰类型的催化剂的现场生成.
- 赛性β-烯酸 (β-BL) 的环开聚合 (ROP).
- 包括立体选择性,热特性和机械测试在内的合成聚3-基酸盐 (PHB) 的表征.
主要成果:
- 通过催化剂系统获得高同选择性β-BL的ROP,产生同选择性PHB.
- 获得了迄今为止 β-BL ROP 的创纪录的生产率 (TOF 高达 32 000 h-1) 和最高的同位选择性 (Pm高达 0.89).
- 合成的PHB具有降低的化温度 (Tm ≈140°C),增加的化处理窗口,以及显著降低的脆性 (破裂时延长392%).
结论:
- 开发的以为基础的催化剂系统能够从β-BL中高效和立体选择性地合成PHB.
- 与细菌PHB相比,化学合成的PHB具有更好的材料特性,包括更高的灵活性和可加工性.
- 这项研究表明,这种合成途径有潜力产生具有聚烯类热力学特性的PHB.
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