在高温下通过电子束辐射对聚3-基酸盐进行无添加物交叉连接
David Krieg1, Michael Thomas Müller2, Regine Boldt2
1Institute for Circular Economy of Bio:Polymers at Hof University (ibp), 95028 Hof, Germany.
Polymers
|October 28, 2023
概括
通过在200kGy以上的化状态辐射,实现了对P3HB的控制的无添加剂交联. 这种方法启动了交叉连接反应,导致凝的形成和物质性质的改变.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 辐射化学 辐射化学
背景情况:
- 聚-3-基酸盐 (P3HB) 在照射时主要经历主链裂变.
- 之前的研究表明P3HB中的无形相交联,但缺乏可控方法和机制理解.
研究的目的:
- 开发一种可控的,无添加剂的方法,使用辐射进行P3HB的交叉连接.
- 调查与P3HB交叉连接相关的机制和由此产生的物质性质变化.
主要方法:
- 在195°C的化状态下对P3HB进行电子或玛辐射.
- 使用凝点 (Dgel) 分析来确定剂量.
- 通过风病学,尺寸排除色谱 (SEC) 和热分析进行表征.
主要成果:
- 在剂量超过200kGy时,达到高达16%的凝形成,在200kGy时确定Dgel.
- 风病学和SEC表示在100250kGy之间的剂量下有分支.
- 热分析显示了双模融化峰值,融化温度降低,热降解温度增加,与分支和交叉连接相一致.
结论:
- 化辐射提供了一种可行的方法,用于控制P3HB的无添加剂交叉连接.
- 辐射诱导的交叉连接显著改变了P3HB的风湿和热性质.
- 该研究提供了关于裂变和交叉连接的G值的见解,有助于理解辐射对P3HB的影响.
关键词:
在G值上,G值是G值.生物聚合物是一种生物聚合物.链条的分支链条的分支链条链条裂变 链条裂变 链条裂变交叉连接 交叉连接 交叉连接电子光束 (e-beam) 是一个电子光束.温度升高导致的温度升高.凝剂量 凝剂量结点是指结点的结点.辐射辐射辐射的辐射.融化的融化化的状态是化的状态.聚-3-基丁酸盐-基酸盐更多相关视频
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