CAMDA扩链聚氨酯脲的硬段对形态与性能的影响

The Effect of Hard Segment Content of CAMDA-Extended Polyurethane-Urea on Morphology and Properties

由红外光谱、核磁共振及质谱分析证实了所合成的3-氯-3’-甲氧基-4,4’-二氨基二苯基甲烷(CAMDA)具有预期的化学结构.用RIM方法制成的CAMDA基聚氨酯脲(PUU)性能接近于DETDA扩链的PUU.用快速手工浇注法制备了一系列由CAMDA扩链的不同硬段含量的PUU样品.采用DSC、SEM观察了硬段含量由10％增加到45％PUU形态的变化,并测量了力学性能.实验结果表明:随着硬段含量增加,PUU的形态由平行间隔的软、硬链段富集区经相互穿叉的软、硬段富集区,进一步聚集成硬链段富集球状超级结构,强度亦相应提高.

A new aromatic diamine (CAMDA) as chain extender for RIM polyurethane-urea (PUU) was synthesized. Structure of CAMDA was confirmed by IR, 1H NMR spectra and MS analysis. CAMDA is a viscous liquid chain extender with proper reactivity which can not only be used for RIM operation but also for casting elastomer. The ultimate physical properties of CAM-DA-extended RIMPUU is close to that of DETDA extended one. A series of CAMDA-extended PUU samples with hard segment content of 10%-45% were prepared for studying morphology by DSC, SEM, the corresponding mechanical properties were measured. The results showed that the hard segment rich domain changed from loosen parallel streaks, interlacing streaks to spherulitic superstructures with increasing the hard segment content, the strength of PUU increased with this trend of morphology change.