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含有双二二部分的聚碳酸盐的合成和高热老化

Tao Lu¹, Wei Fang¹, Qian Zhou¹

¹Shanghai Key Laboratory of Advanced Polymeric Materials, School of Materials Science and Engineering, East China University of Science and Technology Shanghai 200237 China wgz@ecust.edu.cn.

|June 4, 2024

概括

从BNE和BPEF单体合成的新聚碳酸盐表现出增强的水解稳定性和对物理衰老的抗性. 这些先进材料在湿热条件下提供了更好的性能,这对于苛刻的应用至关重要.

科学领域:

聚合物化学聚合物化学
材料科学材料科学材料科学
光学材料光学材料

背景情况:

聚碳酸盐被广泛使用,但在高热压力下可以降解.
开发具有增强稳定性和光学性能的聚碳酸对于先进的应用至关重要.

研究的目的:

合成和表征具有高折射率,低双折射率和优异的高热阻力的新型聚碳酸盐.
研究这些共聚合物的单体结构,水解稳定性和物理衰老之间的关系.

主要方法:

2,2'-bis[4-]2-hydroxyethoxy) -1,1'-binaphthyl (BNE) 和9,9-bis[4-]2-hydroxyethoxy) phenyl]fluorene (BPEF) 的联合聚合. 这两种聚合物中,二氧化和二氧化是最常见的.
对双甲基聚碳酸盐的水解稳定性的比较分析.
在干燥和湿热条件下的物理衰老现象的评估,使用输热量损失测量.
物理衰老与玻璃过渡温度 (Tg) 的相关性.

主要成果:

与双甲聚碳酸相比,BNE-BPEF共聚合物显著改善了水解稳定性.
在酸性热条件下,BNE和BPEF单体的pKa值较高有助于降低体水解.
物理衰老,以热损失表示,与衰老温度和Tg.之间的差异线性相关.
较低的Tg导致更明显的物理衰老和延伸强度/模块的增加,而较高的Tg减轻了衰老.

结论:

BNE和BPEF的共聚化产生了具有出色的水解稳定性和可调整的物理衰老行为的聚碳酸盐.
增强的稳定性与单体性质和降低对水解的敏感性有关.
玻璃过渡温度是控制这些聚碳酸的物理老化和机械性质变化的关键因素.

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