The surface properties, mechanical characteristics, and morphology of the PP/CPA-Fe composite based on a polymer blend of polypropylene (PP) and copolyamide (CPA) filled with dispersed iron (Fe) were studied. The effect of stepwise behavior of the surface energy and its dispersive and polar components was previously unknown and discovered for the first time when the composition of the polymer blend was varied in the entire composition range. The surface parameters were found by measuring the contact angle of the testing liquids (water and diiodomethane) and using Owens and Wendt’s approach. Stepwise behavior of the surface energy was caused by the morphology of the composite. The largest change in the surface parameters occurs in the phase inversion region, where the phases of PP and CPA-Fe are co-continuous. Below (for the structure of PP matrix with the inclusions of CPA-Fe) and above (for the structure of CPA-Fe matrix with the inclusions of PP) this interval, changes in the surface energy are minor. In the phase inversion region, the relative contributions of the polar and dispersive parts to the total surface energy were changed from 1 to 14% and from 99 to 86%, respectively that was caused by the interface interaction of the components of the blend. On the contrary, the values of elastic modulus (E) remain constant in the phase inversion region, while the largest changes occur below and above this region.

研究了基于聚丙烯（PP）和共聚酰胺（CPA）填充有分散铁（Fe）的聚合物共混物的PP / CPA-Fe复合材料的表面性能，力学性能和形貌。当聚合物共混物的组成在整个组成范围内变化时，表面能及其分散和极性组分的逐步行为的影响以前是未知的，并且是首次发现。表面参数是通过测量测试液体（水和二碘甲烷）的接触角并使用Owens和Wendt方法获得的。表面能的逐步行为是由复合材料的形态引起的。表面参数的最大变化发生在PP和CPA-Fe的相共连续的相变区域中。在下面（对于包含CPA-Fe的PP基体结构）和以上（对于包含PP的CPA-Fe基体结构），此区间的表面能变化很小。在相变区域中，极性和分散部分对总表面能的相对贡献分别从1％变为14％，从99％变为86％，这是由共混物各组分之间的界面相互作用引起的。相反，弹性模量的值（分别是由共混物各组分之间的界面相互作用引起的。相反，弹性模量的值（分别是由共混物各组分之间的界面相互作用引起的。相反，弹性模量的值（E）在反相区域保持恒定，而最大变化发生在该区域的上下。