软段对油墨用聚氨酯树脂耐湿热性能的影响

Effects of Soft Segments on the Hygrothermal Property of Polyurethane Resins for Ink

以异佛尔酮二异氰酸酯(IPDI)和异佛尔酮二胺(IPDA)为硬段,以聚氧化丙烯二醇(PPG)、聚四氢呋喃二醇(PTMEG)、聚己二酸新戊二醇酯二醇(PNA)或其混合物为软段,制备了系列聚氨酯(PU)树脂。通过FT-IR、GPC、力学性能及附着牢度测试,研究了软段的结构、组成及含量对PU树脂耐湿热性能的影响。结果表明,以PTMEG为软段的PU树脂具有较好的耐湿热性能,但其黏度过大。以PTMEG部分替代PPG或PNA可提高PU树脂的耐湿热性能。随着软段含量的减少,PU树脂的耐湿热性能提高,吸水率降低。当PPG/PNA/PTMEG质量比为2/2/1,且软段质量分数为73.2%时,PU树脂的黏度接近应用上限,对PET膜的附着牢度保持率最大,达到92.2%。

A series of polyurethane（PU） resins were synthesized with isophorone diisocyanate（IPDI） and iso- phorone diamine （IPDA） as hard segments, and polyoxypropylene glycol （ PPG）, polyoxytetramethylene glycol （ PT- MEG）, polyneopentylene adipate glycol （PNA） or their mixtures as soft segments. The effects of the structure, composition and content of soft segments on the hygrothermal aging property of PU resins were studied by means of fourier transform infrared （FT-IR） spectroscopy, gel permeation chromatography （ GPC ）, mechanical property test and adhesion test. The results showed that, the PU resin with crystallization type PTMEG as the soft segment had higher hygrothermal aging property, but its viscosity was too high. The hygrothermal aging property of PU resins could be improved by replacing PPG or PNA with PTMEG partially. With the decrease of the soft segment content, the hygrothermal aging property of PU resins was improved and the water absorption decreased gradually. When PPG/PNA/PTMEG mass ratio was 2/2/1 and the soft segment content was 73.2%,the viscosity of the PU resin was close to the value of application limit, and the retention ratio of adhesion on PET film was up to 92.2%.