Abstract Waterborne polyurethanes (WBPUs) based on the reaction of unmodified castor oil (CO) with isophorone diisocyanate (IPDI) were synthesized using dimethylolpropionic acid (DMPA) or tartaric acid (TA) as internal emulsifiers. The effect of the incorporation of TA, a bio-based carboxylic acid, in the synthesis of castor oil-based WBPU was carefully investigated. For comparison, two WBPUs were synthesized using DMPA. The chemical changes that took place during the reaction were followed using FTIR. The raw materials and the final polymeric films were characterized by this technique as well as 1H NMR, XRD, DSC, DMA and TGA. Results indicated that in the case of the sample prepared with TA, the isocyanate reacts with the hydroxyls of the acyl groups of the acid additionally to the alcoholic ones. In all cases, the films prepared by casting were translucent and showed glass transition temperatures above room temperature, although comparatively lower for the WBPU formulated with TA. Differences were also observed in the thermal degradation performance of the films. The observed differences were tracked to those in the molecular structures of the WBPUs.

中文翻译：

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蓖麻油和酒石酸水性聚氨酯的合成与表征

摘要 以二羟甲基丙酸 (DMPA) 或酒石酸 (TA) 作为内乳化剂，基于未改性蓖麻油 (CO) 与异佛尔酮二异氰酸酯 (IPDI) 反应合成了水性聚氨酯 (WBPU)。仔细研究了 TA（一种生物基羧酸）在蓖麻油基 WBPU 合成中的影响。为了比较，使用 DMPA 合成了两种 WBPU。使用 FTIR 跟踪反应过程中发生的化学变化。通过该技术以及 1H NMR、XRD、DSC、DMA 和 TGA 对原材料和最终聚合物薄膜进行表征。结果表明，在用 TA 制备的样品的情况下，异氰酸酯除了与醇的羟基反应外，还与酸的酰基的羟基反应。在所有情况下，通过浇铸制备的薄膜是半透明的，并且显示出高于室温的玻璃化转变温度，尽管用 TA 配制的 WBPU 相对较低。在薄膜的热降解性能方面也观察到了差异。观察到的差异被追踪到 WBPUs 的分子结构中的差异。