Polyamide; Methylene to amide ratio; Abrasive wear; Structure–property correlation
Polyamides (PAs) form a major class of tribo-polymers used in almost all types of wear situations. They excel most of the engineering polymers especially in the case of abrasive wear performance. Since methylene (---CH2---) to amide (---CONH---) group ratio in PAs control the physical and mechanical properties, it was thought interesting to examine its influence on tribo-performance also. Hence, two types of PAs (addition and condensation) were selected for the present study. Abrasive wear studies on 10 PAs were done in a single pass condition by abrading a polymer pin against a waterproof silicon carbide (SiC) abrasive paper under various loads. It was observed that CH2/CONH ratio had a significant influence on various mechanical properties such as tensile strength, elongation to break, fracture toughness, fracture energy and therefore, on the abrasive wear performance. It was observed that CH2/CONH ratio and various mechanical properties when plotted individually did not show linear relation in most of the cases, while the specific wear rate as a function of some mechanical properties showed good correlation.