热可逆的有机催化剂,用于加速处理具有抗性的动态网络
Giulia Vozzolo1, Marta Ximenis1, Daniele Mantione1,2
1POLYMAT, University of the Basque Country UPV/EHU, Joxe Mari Korta Center, Avda. Tolosa 72, 20018 Donostia-San Sebastian, Spain.
ACS macro letters
|November 1, 2023
概括
研究人员开发了一种可逆催化剂,四甲基瓜尼迪盐 (TPB:TMG),用于共价适应性网络. 这种催化剂可以在高温下快速交换键,并在较低的工作温度下防止变形,从而允许多个再加工周期.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 催化剂是一种催化剂.
背景情况:
- 协价适应性网络需要控制的键交换,以便在没有永久变形的情况下进行再加工.
- 潜伏催化剂提供时空控制,但往往遭受不可逆转的激活,导致爬行.
- 具有工业意义的含二硫化物聚氨网络 (PU) 可以使用基质催化剂进行动态交联.
研究的目的:
- 为共价适应性网络开发一种催化剂,允许在高温下快速交换债券,并在使用温度下防止爬行.
- 调查使用热可逆催化剂来重新处理含有二硫化物的PU网络.
主要方法:
- 合成并表征了一种四乙甲基瓜尼迪尼盐 (TPB:TMG) 作为热可逆催化剂.
- 纳入TPB:TMG作为二硫化物含有聚氨网 (PU) 的添加剂.
- 评估了修改后的PU网络的催化活性,热可逆性,爬行阻力和再加工能力.
主要成果:
- TPB:TMG证明了可逆的热解离,在加热时释放了活性基催化剂 (TMG).
- 添加TPB:TMG有效地防止了在较低温度下PU网络中的爬行变形.
- 由于受控的债券交换,TPB:TMG在高温下使含有二硫化物PU网络的高效再加工成为可能.
- 实现了多个再处理周期,而不会损害在使用温度下无爬行状态.
结论:
- 热可逆的有机催化剂,如TPB:TMG,为控制玻璃体网络中的动态交换提供了可行的解决方案.
- 这种方法克服了不可逆转的催化剂的局限性,使得在工作温度下提高机械稳定性和再加工能力.
- 可逆催化系统为工业应用先进的共价适应性网络提供了巨大的潜力.
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