异酸盐结构对聚氨特性的影响:合成,性能和自我愈合特性
Hairui Wang1, Lan Cao1, Xiaolei Wang1
1School of Polymer Science and Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
Polymers
|November 9, 2024
概括
异酸盐的结构显著影响聚氨的特性,影响聚合,自我愈合和机械强度. 这项研究合成了五种聚氨,揭示了不同的异酸盐选择如何影响材料性能和可回收性.
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
背景情况:
- 聚氨 (PU) 是对弹性体,粘合剂和自我愈合应用至关重要的多功能聚合物.
- 选择异酸盐是定制PU特性的关键.
研究的目的:
- 研究各种异酸盐结构对合成聚氨材料的影响.
- 系统地分析对聚合率,结,热性质,相分离,可湿性,自我愈合,粘合力和机械特性的影响.
主要方法:
- 使用常见的芳香性 (MDI,TDI) 和性 (HDI,IPDI,HMDI) 异酸盐与聚甲乙醇 (PTMG) 和1,4-butanediol (BDO) 合成五种PU材料.
- 系统地研究聚合动力学,结合,热行为,相分离,可湿性,自我愈合,粘附性和机械性能.
主要成果:
- 异酸盐对称性与键正相关,而过度的灵活性或结晶性可能会阻碍它.
- 基于MDI的PU显示了最高的键索引 (4.10),明显的相位分离,以及最高的抗拉强度 (23.4 MPa).
- 基于HMDI的PU表现出优越的粘合力 (切强度7.9MPa) 和划伤愈合. 基于IPDI的PU在热处理后显示出出色的自我愈合能力.
结论:
- 异酸盐结构是聚氨性能的关键决定因素,影响结,机械强度,粘合力和自我愈合.
- 合成的聚氨显示出基于异酸盐选择的调节性质,为各种应用提供了潜力.
- 所有研究的PU材料都通过化或溶液再加工表现出极好的可回收性.
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