侧链含分散红类染料基团的聚(氨酯-酰亚胺)的合成与表征

采用两步法合成了4种侧链含偶氮染料发色团分散红-19的新型聚(氨酯-酰亚胺)(PUI):先合成含染料发色团的二异氰酸酯,再进一步和二酐单体缩合生成PUI.用红外光谱、紫外-可见光谱、DSC和TGA等手段对合成的PUI进行表征.所有PUI在～490nm处都有一强吸收峰.PUI可溶于强极性非质子溶剂,如NMP,DMAc,DMF,DMSO和1,4-丁内酯,有些甚至在常用的低沸点溶剂如THF中也可溶解.PUI的特性粘数在0.16～0.31dL/g范围内.其玻璃化转变温度(Tg)在171～211℃范围内,明显高于侧链型非线性光学聚氨酯(PU).以刚性相对较大的六氟异丙叉基二(3,4-邻苯二甲酸酐)(6FDA)和甲苯-2,4-二异氰酸酯(TDI)为单体的PUI具有比以二苯醚-3,3′,4,4′-四甲酸二酐(OPDA)和4,4′-二异氰酸酯二苯甲烷(MDI)为单体的PUI更高的T_g.PUI的TGA曲线上有两个明显的失重台阶,起始热分解温度大约在300℃左右.

Synthesis and Characterization of Poly(urethane-imide)s Containing a Disperse Red Type Chromophore in the Side-chain

Four novel poly(urethane imide)s(PUIs) containing a diazo nonlinear optical chromophore in the side chain were synthesized by a two step process, which includes preparation of diazo chromophore containing diisocyanates followed by the condensation reaction with dianhydrides. The PUIs obtained were characterized by FTIR spectroscopy, UV-Vis spectroscopy, DSC and TGA. All PUIs exhibit a maximum UV-Vis absorption of the diazo chromophore at the wavelength of about 490 nm. They are soluble in aprotic solvents such as NMP, DMAc, DMF, DMSO and 1,4-butyrolactone. Some are even soluble in common low boiling point solvents such as THF. The high organo solubility of PUIs results from the existence of the flexible urethane moiety in the backbone and a side chain chromophore, which leads to loose chain packing and enlarge free volume. The intrinsic viscosities of PUIs are 0.16~0.31 dL/g. The PUIs possess glass transition temperatures( T_g) at 171~211 ℃, which are much higher than the corresponding side chain nonlinear optical(NLO) polyurethanes. PUIs based on 4,4′-(hexafluoroisopropylidene) diphthalic anhydride(6FDA) and tolulene 2,4-diisocyanate(TDI) possess higher T_g than those based on 3,3′ , 4,4′-diphenylether-tetracarboxylic acid dianhydride(OPDA) and methylenediphenylene diisocyanate(MDI). Two steps of weight loss are found in TGA curves of PUIs. The initial decomposition temperatures of PUIs are around 300 ℃, which is attributed to the thermal decomposition of the urethane moiety and the side chain chromophore.