Abstract

Heterogeneous blends of millable polyurethane (MPU) and ethylene-co-vinyl acetate (EVA) elastomers have been prepared by conventional open mill mixing, and subsequently cured with DCP as curing agent. The prepared blends were characterized by TGA, DSC, XRD and DMA techniques. Mechanical and solvent transport features have been evaluated. Examination of EVA phase crystallization dynamics revealed that the 50:50 blend possessed a higher energy barrier during crystallization. When EVA became the minor or major phase, the system offers similar energy barrier features. Solvent transport mechanism has been found to shift towards non-Fickian for blends with EVA as the major phase. Mechanical properties have been found to be complementary to the observed crystalline features of the blends. A blend with EVA to MPU ratio 80:20 is highlighted as a soft and strong material, with enhanced solvent resistance features suitable as a matrix for different engineering applications.

Graphical abstract

摘要

可研磨的聚氨酯（MPU）和乙烯-乙酸乙烯酯（EVA）弹性体的异质共混物已经通过常规的开炼机混合制备，然后使用DCP作为固化剂进行固化。所制备的共混物通过TGA，DSC，XRD和DMA技术表征。机械和溶剂传输功能已得到评估。EVA相结晶动力学的检查表明，50:50的共混物在结晶过程中具有较高的能垒。当EVA成为次要或主要阶段时，该系统提供了类似的能量屏障功能。对于以EVA为主要相的共混物，溶剂传输机制已向非Fickian转移。已经发现机械性能与所观察到的共混物的晶体特征互补。EVA与MPU的比例为80：