端环氧基聚缩水甘油醚硝酸酯的合成及固化

针对聚缩水甘油醚硝酸酯(PGN)与异氰酸酯固化反应易受环境水分影响、固化稳定性较差等问题,合成了端环氧基聚缩水甘油醚硝酸酯(e-PGN)。采用红外(IR)、核磁(NMR)和凝胶渗透色谱(GPC)进行了结构表征。测试了改性前后聚合物的主要物化性能。e-PGN的玻璃化转变温度、粘度、密度、热分解温度等主要物性与PGN的主要物性相近。研究了e-PGN与几种环氧固化剂咪唑(IMD)、邻苯二甲酸酐(PA)、N-乙基乙二胺(NEED)、异佛尔酮二胺(IPDA)等]的固化反应。结果表明,e-PGN可与IMD、PA、NEED、IPDA等在60℃/70℃下反应固化,其中以PA为固化剂时,固化物力学性能最好,拉伸强度为0.912 MPa,断裂伸长率为354%;室温贮存8个月的固化试样其力学性能基本不变。

Synthesis and Curing of Epoxy-teminated Poly(glycidyl nitrate)

The reaction between the end hydroxyl of poly(glycidyl nitrate)(PGN) and isocyanates is easily affected by ambient moisture,and the curing stability is poor.Aiming at these problems,epoxy-terminated poly(glycidyl nitrate) (e-PGN) was synthesized.Its structure was characterized by infrared spectroscopy(IR),nuclear magnetic resonance(NMR) and gel permeation chromotagraph(GPC),and its major physiochemical properties were tested.The main physical properties of e-PGN,such as glass transition temperature,viscosity,density,thermal decomposition temperature,were close to those of PGN.The curing reactions of e-PGN with epoxy curing agents,such as imidazole(IMD),o-phthalic anhydride(PA),n-ethylethylenediamine(NEED) and isophoronediamine (IPDA) were studied.Results show that the curing reaction of e-PGN with IMD,PA,NEED and IPDA at 60 ℃/70 ℃ can be performed.When PA is used as curing agent,the mechanical properties of the cured material outperformed;the tensile strength is 0.912 MPa,and the elongation at break is 354％.In addition,the mechanical properties of the cured samples stored at room temperature for 8 months remained almost unchanged.