Abstract:

A new class of polyether-urea-based benzoxazine(PUBZ) exhibits perfect toughness properties after thermal treatment has been developed and synthesized via two steps.Firstly, amine-terminated polyether-based polyurea was synthesized using amine-terminated polyether and diphenyl methane diisocyanate(MDI) as raw materials.Secondly, PUBZ was prepared from amine-terminated polyether-based polyurea, bisphenol-A and paraformaldehyde through Mannich reaction.The structure of PUBZ has been confirmed by FTIR and ¹H NMR.The curing behavior was characterized by DSC.The effect of different length of polyether chains on the mechanical properties of PUBZ has been evaluated by dynamic mechanical analysis(DMA) in a tensile deformation.Thermal properties of PUBZ have been studied by DMA and thermogravimetric analysis(TGA).The results showed that the longer polyether chains, the higher curing temperature of the PUBZ.The lower glass transition temperature of the PUBZ, the better thermal stability.When the molecular weight of amine-terminated polyether was 400 and D-400/PUBZ resin exhibited the highest toughness.

Key words: polyether, polyurea, benzoxazine, high toughness, synthesis, mechanical property, thermal stability

摘要：

首先用端氨基聚醚、二苯甲烷二异氰酸酯（MDI）制备出两端含有氨基的聚醚型聚脲，然后用合成的聚醚型聚脲、双酚A和多聚甲醛为原料进行曼尼希反应合成出聚醚脲型苯并（口恶）嗪（PUBZ），经高温固化后形成韧性优良的树脂。用FTIR、¹H NMR分析了PUBZ的化学结构，证实了所得的目标产物；用DSC对PUBZ的固化特性进行研究；用拉伸测试分析了含不同长度聚醚链PUBZ树脂的力学性能；用DMA和TGA测试分析了含不同长度聚醚链PUBZ树脂的热性能。结果表明：聚醚链段越长，PUBZ的固化温度越高，PUBZ树脂的玻璃化转变温度越低，相反其热稳定性越好；在力学性能中端氨基聚醚D-400/PUBZ树脂的韧性最好。

关键词: 聚醚, 聚脲, 苯并嗪, 高韧性, 合成, 力学性能, 热稳定性