Sliding wear of polyimide-C60 composite coatings

Thermal desorption of fullerene C60 from polymer matrices

“…prepared by C 60 introduction into diamine exhibit more rough morphology compared to that obtained by fullerene introduction into the polyamic acid [20]. TSD experiments performed on PI-C 60 blends are shown in Fig.…”

“…Polyamic acid was synthesized from 3,3 0 ,4,4 0 -oxydiphthalic anhydride (ODPA), p-phenylenediamine (PPD), and 2,5-bis(4-aminophenyl) pyrimidine (APP) [19]. As it has been shown in the first works on tribology of the PI-fullerene composites, the fullerene introduction into polyamic acid leads to the decrease in the wear rates of the composite coatings [20,21]. The components of the ODPA-PPD-APP copolyimide were taken in the molar ratio 100:50:50.…”

“…A number of methods, e.g., SEM, FTIR [20] and X-ray diffraction [23] indicate, though not unequivocally, the C 60 presence inside PI matrix in complicated structural states. SEM evidences the presence of agglomerates inside PI-C 60 composite ranging in size from about 5 lm (mean interparticle distance above $5 lm) down to the resolution limit of the method [20].…”

“…SEM evidences the presence of agglomerates inside PI-C 60 composite ranging in size from about 5 lm (mean interparticle distance above $5 lm) down to the resolution limit of the method [20]. X-ray diffraction in small angles shows that the spectrum of neat polyamic acid reveals a peak, indicating the appearance of an electron density fluctuation length of the order of 10 nm [23].…”

Preparation and tribological properties of polyimide/carbon sphere microcomposite films under seawater condition

“…Pozdnyakov investigated the sliding friction and wear characteristics of pyrimidine-containing polyimide (PI) coatings and PI-C 60 composite. The result showed that the introduction of C 60 could improve further the wear characteristics of the coatings down to specific wear rates below 2 Â 10 À 7 mm 3 /Nm and suggest that the role of the C 60 molecules in reducing the wear of composite coatings is due to the interactions between C 60 and the PI [20]. Due to C 60 which is a kind of carbon spheres, the tribological behavior of polymers also might be improved through the introduction of carbon spheres into a mechanically and thermally stable polymer, such as PI.…”