Abstract In this study, the fully degradable soybean oil-based waterborne polyurethanes (SWPU) were prepared, and the mechanical properties, thermal properties and hydrophilicity of SWPU films were adjusted by changing the R value. First, soybean oil-based polyol was fabricated via epoxy soybean oil and ricinoleic acid in the absence of solvent and catalyst. Then, the resulting polyol was mixed with isophorone diisocyanate (IPDI), dimethylolpropionic acid (DMPA), trimethylamine (TEA) and ethylenediamine (EDA) to synthesize polyurethane emulsion with different R value (the molar ration of -NCO/-OH). The result showed that as the R value increased, the tensile strength of SWPU film was increased from 10.02 to 27.32 MPa, the initial decomposition temperature of polyurethane films was improved from 201 ℃ to 246 ℃, the Tg,h was increased from 68 to 130 ℃ and the water contact angle of SWPU films were enhanced from 82.4 ° to 95.5 °. It can be explained that the degree of crosslinking of the polyurethane elastomer was improved and the interaction of the molecular chains became stronger with larger R value. Also, all SWPU films were placed in the 3 wt.% sodium hydroxide solution at 45 ℃ to test the degradability, and the weight loss of samples at different degradation time were calculated, respectively. Finally, the morphology, FT-IR and tensile strength of samples was observed before and after degradation, and a possible mechanism of degradation was studied. The technique reported here demonstrated that it was possible to develop the degradable materials.

中文翻译：

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机械热性能可调的可降解植物油基水性聚氨酯的制备

摘要 本研究制备了可完全降解的豆油基水性聚氨酯（SWPU），通过改变R值来调节SWPU薄膜的力学性能、热性能和亲水性。首先，在没有溶剂和催化剂的情况下，通过环氧大豆油和蓖麻油酸制备大豆油基多元醇。然后，将所得多元醇与异佛尔酮二异氰酸酯（IPDI）、二羟甲基丙酸（DMPA）、三甲胺（TEA）和乙二胺（EDA）混合，合成不同R值（-NCO/-OH的摩尔比）的聚氨酯乳液。结果表明，随着 R 值的增加，SWPU 薄膜的拉伸强度从 10.02 MPa 增加到 27.32 MPa，聚氨酯薄膜的初始分解温度从 201 ℃提高到 246 ℃，Tg、h从68℃提高到130℃，SWPU薄膜的水接触角从82.4°提高到95.5°。可以解释为聚氨酯弹性体的交联度提高，R值越大分子链相互作用越强。同时，将所有SWPU薄膜置于45℃的3wt.%氢氧化钠溶液中测试降解性，并分别计算不同降解时间下样品的失重。最后，观察降解前后样品的形貌、红外光谱和拉伸强度，并研究降解的可能机制。此处报道的技术表明开发可降解材料是可能的。可以解释为聚氨酯弹性体的交联度提高，R值越大分子链相互作用越强。同时，将所有SWPU薄膜置于45℃的3wt.%氢氧化钠溶液中进行降解性测试，并分别计算不同降解时间下样品的失重。最后，观察降解前后样品的形貌、红外光谱和拉伸强度，并研究降解的可能机制。此处报道的技术表明开发可降解材料是可能的。可以解释为聚氨酯弹性体的交联度提高，R值越大，分子链间的相互作用越强。同时，将所有SWPU薄膜置于45℃的3wt.%氢氧化钠溶液中测试降解性，并分别计算不同降解时间下样品的失重。最后，观察了降解前后样品的形貌、红外光谱和拉伸强度，并研究了可能的降解机制。此处报道的技术表明开发可降解材料是可能的。%氢氧化钠溶液在45℃下测试降解性，并分别计算不同降解时间样品的失重。最后，观察降解前后样品的形貌、红外光谱和拉伸强度，并研究降解的可能机制。此处报道的技术表明开发可降解材料是可能的。%氢氧化钠溶液在45℃下测试降解性，并分别计算不同降解时间样品的失重。最后，观察降解前后样品的形貌、红外光谱和拉伸强度，并研究降解的可能机制。此处报道的技术表明开发可降解材料是可能的。