基于细分和精确表征的可调节热固化环氧体
Claudio Gioia1, Giada Lo Re1, Martin Lawoko1
1Wallenberg Wood Science Center, WWSC, Department of Fiber and Polymer Technology , KTH Royal Institute of Technology , 100 44 Stockholm , Sweden.
Journal of the American Chemical Society
|March 3, 2018
概括
这项研究合成了来自卡夫的新型耐热树脂,并引入了氧化基组以形成环氧体. 的结构直接影响最终的环氧耐热性质,使得定制材料的设计成为可能.
科学领域:
- 聚合物化学
- 材料科学
- 生物质利用
背景情况:
- 化是一种大量但未充分利用的芳香聚合物的副产品.
- 开发高价值的素应用对于可持续的化学工业至关重要.
- 现有的基于木质素的热通常缺乏可预测的结构-属性关系.
研究的目的:
- 从特定的低摩尔质量Kraft素分离物中合成和表征耐热性环氧树脂.
- 调查素结构变化对产生的环氧热的热力学性能的影响.
- 建立在基结构和最终环氧网络性能之间直接的相关性.
主要方法:
- 用溶剂提取,以分离具有高功能的卡夫素部分.
- 使用P NMR,2D-HSQC NMR,SEC和DSC进行全面的结构特征.
- 通过H NMR量化引入活性氧化部分的素的化学修饰.
- 修饰的木质素与聚乙烯二胺交联形成环氧热.
- 通过DSC,DMA,拉力测试和SEM进行热力学性能评估.
主要成果:
- 从精制的Kraft素分离物中成功合成了耐热性环氧树脂.
- 从不同的素结构中获得的环氧体在热力学特性 (例如,玻璃过渡温度,模量) 中表现出显著的差异.
- 建立了明确的结构属性关系,将特定的素分子特征与环氧网络性能联系起来.
- 在温和的条件下将氧化基组引入素骨干.
结论:
- 这项研究表明,从量身定制的Kraft素分离物中获得高性能热凝固的可行途径.
- 首次实现了素结构特征和环氧耐热性质之间的直接相关性.
- 这种方法提供了一个强大的平台,用于设计和调整使用真实素原料的基于素的环氧材料,超越模型化合物.
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