异氰酸酯类型对蓖麻油基聚氨酯性能的影响

Effect of Isocyanate Types on Properties of Castor Oil-based Polyurethane

以4,4-二环己基甲烷二异氰酸酯(HMDI)、异氟尔酮二异氰酸酯(IPDI)、蓖麻油基多元醇为主要原料,在不添加扩链剂及交联剂的情况下,采用两步法(预聚体法)制备了蓖麻油基聚氨酯材料。通过动态力学性能(DMA)、热失重(TGA)及力学性能测试等手段对聚氨酯材料的性能进行测试,探究异氰酸酯类型及溶剂对蓖麻油基聚氨酯材料性能的影响。结果表明:HMDI型聚氨酯材料的拉伸强度与耐热性能均优于IPDI型聚氨酯材料,但IPDI型聚氨酯材料的断裂伸长率相对较高;采用丙酮作为溶剂会在降低材料拉伸强度与耐热性能的同时提高材料的断裂伸长率;蓖麻油基聚氨酯材料具有较高的损耗因子(tanδ),因此其具有优异的阻尼性能,有效阻尼温域集中于常温区域。

Castor oil-based polyurethane materials were prepared by two-step method(prepolymer method) with 4,4-dicyclohexylmethane diisocyanate(HMDI), isofluorone diisocyanate(IPDI) and castor oil-based polyols as the main materials(without the chain extenders and cross-linking agents). The properties of the polyurethane materials were tested by dynamic mechanical properties(DMA), thermogravimetry(TGA) and mechanical properties test. The influences of the isocyanate types and solvent on the properties of castor oil-based polyurethane materials were investigated. The results show that the tensile strength and heat resistance of the HMDI polyurethane materials are better than that of the IPDI polyurethane materials, but the IPDI polyurethane materials have higher elongation at break. Acetone(as the solvent) will increase the elongation at break of the material while reducing the tensile strength and heat resistance of the material. Castor oil-based polyurethane materials have a high loss factor(tanδ), so they have excellent damping properties, and the effective damping temperature range is concentrated at normal temperature region.