Preparations and tribological properties of COPNA copolymer materials

摘要

The cured condensed polynuclear aromatic (COPNA) resin has excellent thermal stability and self-lubricating property which is popular for friction materials. However the cured resin has brittleness and poorly molding process due to its high cross-linking density. In this paper, the allyl-COPNA-BMI copolymer resin is prepared via a solution polymerization method, its structure, and its mechanical and tribological properties are investigated with FT-IR, SEM, TGA techniques. The copolymer anti-friction and anti-wear behaviors are tuned by varying the N,N'-4,4'-diphenylmethane-bismaleimide(BMI) monomer loading. The mechanical properties of the copolymer is the best when the BMI loading is 20 wt% upon these results. The tensile and impact strength of the copolymer/BMI 20 wt% is 12 MPa and 13.9 MPa, respectively. The lowest friction coefficient of copolymer/BMI 30wt% is 0.27, and its abrasion rate is 0.601510~(-6) mm~3/Nm. The initial thermal decomposition temperature of the copolymer/BMI 40wt% is 400 °C and 46.5 wt% of char residue ratio at 642 °C. The copolymer resins exhibit good thermal stability, abrasive resistance and mechanical properties compared to the pure COPNA.