软段结构对聚氨的性能的影响
Ivan Ristić1, Suzana Cakić2, Nevena Vukić3
1Faculty of Technology Novi Sad, University of Novi Sad, Bulevar cara Lazara 1, 21102 Novi Sad, Serbia.
Polymers
|September 28, 2023
概括
研究人员使用不同比例的聚乙烯,L-乳化物 (PDLLA) 和聚二醇 (PCL) 软片段合成聚氨 (PU). 调整PDLLA含量有效调整了PU特性,并影响了微相分离和结晶行为.
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
- 生物材料工程 生物材料工程
背景情况:
- 聚氨 (PU) 是具有可调节性质的多功能聚合物.
- 开发具有可控特性的新型PU对于先进应用至关重要,特别是在生物材料中.
- 聚聚合物,如聚D,L-乳化物 (PDLLA) 和聚烯二醇 (PCL),在PU合成中提供了软段修饰的潜力.
研究的目的:
- 合成聚氨 (PU) 使用不同比例的PDLLA和PCL作为软细分而没有链延长器.
- 研究软片组成对产生的聚氨分子结构,热性质和形态学的影响.
- 为特定应用,特别是生物材料中微调PU特性建立一种方法.
主要方法:
- 多二酸与合成的PDLLA和PCL巨醇的一步聚合.
- 福里埃转换红外光谱 (FTIR) 用于分子结构分析.
- 核磁共振 (NMR) 谱法用于结构确认.
- 热重力测量分析 (TGA) 和差分扫描热量测量 (DSC) 用于测量热特性.
- 广角X射线散射 (WAXS) 用于评估结晶性和微相分离.
主要成果:
- 在软片段中改变PDLLA的摩尔比率在微调PU特性方面被证明是有效的.
- 软片组合对热稳定性的影响最小,因为具有可比的聚聚结构.
- PDLLA含量显著影响了微相分离和PCL在软片段的结晶行为.
- PCL结晶的程度取决于硬段度和PDLLA/PCL比率,纯PCL的结晶度达到34.8%.
- 软片段的组成直接影响了所获得的聚氨薄膜的特性.
结论:
- 合成方法可以通过调整软片组合来精确控制聚氨的特性.
- 将PDLLA纳入PCL软片段可以修改微相分离并限制PCL结晶.
- 这些发现为定制聚氨特性以适应所需的应用提供了途径,特别是在生物材料领域.
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