Plastic deformation-induced orientation of kaolinite nanocrystals in ultrahigh-molecular weight polyethylene

The article deals with the investigation of the kaolinite plate orientation in ultra-high-molecular polyethylene. Kaolinite nanocrystals are in the form of thin plates, usually they are nanocrystalline materials. Samples of different degree of kaolinite plate ordering in ultra-high-molecular polyethylene were prepared by the solid phase extrusion. In the article, the degree of kaolinite ordering was investigated by two methods. The first method is based on studying the angular dependence of the EPR spectrum for Fe3+ ions which are present in natural kaolinite as an impurity. The second method is the X-ray diffraction technique. The both methods have shown that the solid-phase extrusion enables one to produce composites with kaolinite filler plates ordered in direction of the extrusion gradient.