Effect of the Molecular Weight of Polyarylene Ether Ketones on the Tribological Properties

Resumo

The effect of the molecular weights of amorphous polyarylene ether ketone (PAEK) synthesized by the reaction of 4,4'-difluorobenzophenone with 2,2-bis (4'-hydroxyphenyl) propane (bisphenol A) potassium diphenolate on its tribological characteristics has been studied. In the case of the friction of a sample with M_w < 200 × 10³ Da, its high wear resistance and the coefficient of friction decreased to 0.4, even at high pressures of up to 10 MPa. These properties of high-molecular-weight PAEK are due to the high contribution of the weak dispersion forces into the intermolecular interaction energy of the polymer. Low wear determines the nature of tribodestruction, which, during the process of self-organization, leads to the appearance of a positive gradient in the physicomechanical properties in the surface layers. The XPS study shows that, during PAEK pressing at 260°C, the intensive oxidation of a thin surface layer occurs.