主链含酰亚胺环和炔基的聚酰亚胺型聚氨酯弹性体的合成及阻燃性能

以均苯四甲酸酐、 D,L-苯丙氨酸和1,4-丁炔二醇为原料合成了一种含有酰亚胺环和炔基的二醇, 并以其为扩链剂, 采用预聚体法, 与4,4-二苯基甲烷二异氰酸酯(MDI)和聚四氢呋喃醚二醇(PTMG)反应, 合成了不同硬段含量的主链含有酰亚胺环和炔基的热塑性聚酰亚胺型聚氨酯弹性体. 用红外光谱(FTIR)、 电子拉力机、 热失重分析(TG)、 广角X射线衍射(XRD)、 UL-94垂直燃烧和极限氧指数对聚酰亚胺型聚氨酯弹性体进行了表征. 结果表明, 这种聚氨酯呈现出无定形结构; 其拉伸强度随着硬段含量的增加而增大; 与传统的热塑性聚氨酯相比, 酰亚胺环和炔基改性的聚酰亚胺型聚氨酯弹性体的热分解过程非常缓慢, 呈现出较好的热稳定性; 不同硬段含量的聚酰亚胺型聚氨酯弹性体的UL-94垂直燃烧均达到V-2级别; 其极限氧指数随着硬段含量的增加而增大.

Synthesis and Flame Retardancy of Novel Thermally Stable Poly(imideurethane)s Containing Imide and Alkynyl Groups in Main Chain

A kind of glycol containing imide and alkynyl function was synthesized from pyromellitic dianhydride(PMAD), butynediol(2-butyne-1,4-diol) and D,L-phenylalanine(DLP). Linear imide and alkynyl modified thermoplastic poly(imide-urethane)s were prepared by the obtained glycol, 4,4'-diphenylmethane diisocyanate(MDI) and poly(tetrahydrofuran)(PTMG) via prepolymerization. The poly(imide-urethane)s structures were characterized with Fourier transform infrared spectroscopy(FTIR), universal testing machine tension, thermalgravimetric analysis(TGA), wide-angle X-ray diffraction(XRD). The results showed that the novel thermoplastic poly(imide-urethane)s elastomer with amorphous structure were successfully synthesized. The tensile strength increases with the hard segment contents. Comparing with the conventional thermoplastic polyurethanes extended by 1,4-butanediol, the poly(imide-urethane)s show slower thermal degradation rate during the degradation process. The polymers with different hard segments contents all reach a UL-94 V-2 rating, and the limiting oxygen index(LOI) value increases with different hard segments contents.