Asensio Manuel, Ferrer Juan-Francisco, Nohales Andrés, Culebras Mario, Gómez Clara M
Institute of Materials Science, University of Valencia, 46980 Paterna, Spain.
Plastics Technology Centre (AIMPLAS), 46980 Paterna, Spain.
Materials (Basel). 2023 Feb 15;16(4):1633. doi: 10.3390/ma16041633.
Segmented thermoplastic polyurethanes (PU) were synthetized using a polycarbonatediol macrodiol as a flexible or soft segment with a molar mass of 2000 g/mol, and different diisocyanate molecules and 1,4-butanediol as a rigid or hard segment. The diisocyanate molecules employed are 3,3'-Dimethyl-4,4'-biphenyl diisocyanate (TODI), 4,4'-diphenylmethane diisocyanate (MDI), 4,4'-Methylenebis(phenyl isocyanate) 1-isocyanato-4-[(4-phenylisocyanate)methyl]benzene and 1-isocyanate-4-[(2-phenylisocyanate) methyl]benzene (ratio 1:1) (MDIi), isophorone diisocyanate (IPDI), and hexamethylene diisocyanate (HDI). The polyurethanes obtained reveal a wide variation of microphase separation degree that is correlated with mechanical properties. Different techniques, such as DSC, DMA, and FTIR, have been used to determine flexible-rigid segment phase behavior. Mechanical properties, such as tensile properties, Shore D hardness, and "compression set", have been determined. This work reveals that the structure of the hard segment is crucial to determine the degree of phase miscibility which affects the resulting mechanical properties, such as tensile properties, hardness, and "compression set".
使用摩尔质量为2000 g/mol的聚碳酸酯二醇大分子二醇作为柔性或软段，以及不同的二异氰酸酯分子和1,4 -丁二醇作为刚性或硬段，合成了分段热塑性聚氨酯（PU）。所使用的二异氰酸酯分子为3,3'-二甲基-4,4'-联苯二异氰酸酯（TODI）、4,4'-二苯基甲烷二异氰酸酯（MDI）、4,4'-亚甲基双（苯基异氰酸酯）1-异氰酸根合-4-[(4-苯基异氰酸酯)甲基]苯和1-异氰酸根合-4-[(2-苯基异氰酸酯)甲基]苯（比例1:1）（MDIi）、异佛尔酮二异氰酸酯（IPDI）和六亚甲基二异氰酸酯（HDI）。所得到的聚氨酯显示出微相分离程度的广泛变化，这与机械性能相关。已使用不同技术，如差示扫描量热法（DSC）、动态热机械分析（DMA）和傅里叶变换红外光谱法（FTIR）来确定柔性-刚性链段的相行为。已测定了机械性能，如拉伸性能、邵氏D硬度和“压缩永久变形”。这项工作表明，硬段的结构对于确定影响所得机械性能（如拉伸性能、硬度和“压缩永久变形”）的相混溶程度至关重要。
