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本文研究了软段为胺端基聚环氧丙烷(分子量为2050),硬段为4,4′-二苯甲烷二异氰酯,用二乙基甲苯二胺进行扩链嵌段聚脲的RIM成型。结果表明,硬段含量为30%的RIM浆脲在各种成型条件下都是有韧性的弹性体。硬段含量70%的RIM聚脲在脱模时极脆,在室温下放置,韧性略有增加,但无商业上的应用价值。硬段含量50%的RIM聚脲可以是从极脆到极富韧性的材料,取决于成型温度和脱模时间。较高的成型温度或较长的成型时间,可以得到韧性较好的聚脲。对脱模后聚脲的脆性与存在硬段低聚体有关进行了讨论。
In this paper, the soft segment amine terminated polypropylene oxide (molecular weight of 2050), the hard segment of 4,4’-diphenylmethane diisocyanate, diethyl toluenediamine poly RIM molding. The results show that RIM slurry urea with a hard segment content of 30% is a tough elastomer under all forming conditions. RIM polyurea with hard segment content of 70% is extremely brittle during demolding and is placed at room temperature with slight increase in toughness, but without commercial application value. RIM polyureas with a hard segment content of 50% can be extremely brittle to very tough materials, depending on the molding temperature and demold time. Higher molding temperature or longer molding time, you can get better toughness of polyurea. The fragility of polyurea after demolding is related to the presence of hard segment oligomers.