聚氨酯环氧树脂乳液互穿聚合物网络结构与性能研究

STUDIES ON STRUCTURE AND PROPERTIES OF POLYURETHANE-EPOXY RESIN LATEX INTERPENETRATING POLYMER NETWORK

分别以聚四氢呋喃(PTMG)和聚己二酸丁二酯(PBA)为聚氨酯(PU)软段,制备了高环氧树脂(EP)含量的PU/EP乳液互穿聚合物网络(LIPN).通过红外光谱,动态力学分析,原子力显微镜等研究了不同类型软段对LIPN结构与性能的影响.结果表明,LIPN结构已经形成,PU与EP间无化学键结合.以PBA为PU软段制备的LIPN中PU与EP相容性更好,分相程度相对低,互穿程度高,导致EP对PBA软段运动的限制作用较强,EP含量的变化对LIPN的玻璃化转变温度影响更大.研究样品的力学性能和溶剂溶胀性能发现,PBA为软段制备的LIPN均优于以PTMG为软段制备的LIPN,水溶胀率等有大幅减小,表现出明显的互穿协同效应.

The polyurethane （PU） latex interpenetrating polymer networks （LIPN） with high contents of the epoxy resin （EP） were prepared, using polytetrahydrofuran glycol （PTMG） and polybutylene adipate （PBA） as soft segments respectively. The structure and properties of the samples with different soft segments were investigated by FFIR, DMA and AFM. The results revealed that the LIPN had formed and with no chemical bond between PU and EP. PU and EP had higher interpenetrating properties in LIPN and lower degree of phase separation with the increase in the content of EP when using PBA as the soft segments because the better compatibility between EP and PBA. The PU samples generally had a higher tensile strength when using PBA as soft segments compared to the samples using PTMG as soft segments, but because PBA and EP had higher interpenetrating properties, the samples showed obviously synergistic effect of IPN, the moving of PBA soft segments were limited more by epoxy resin compared with that of PMTG soft segments, resulting in the tensile strength of LIPN samples with high contents of the epoxy resin decline faster, in the same time the glass transition temperature of the LIPN samples has also rising faster. The solvent resistance of the LIPN using PBA as soft segments is vastly superior to that of the samples using PTMG as soft segments.