A novel fullerene-styrene-maleic anhydride copolymer is reported. TEM analyses shows it is water- soluble nanoball of average diameter of about 83 nm. The tribological behavior is evaluated by foul-ball machine. It was found that addition of fullerene copolymer to base stock (2%triethanolamine aqueous solution)resulted in a raise in load-carrying ability(F value)from 130 N to maximum 480 N, and a reduction in coefficient of friction from 0.235 to minimum 0. 063. SEM analyses indicates that the wear scare obtained with fullerene copolymer exhibited mild scratches, while sharp grooving and serious pull-out phenomnon were observed in the presence of base stock without additive .The improvements in friction, wear and load-carrying capacity are probably due to the presence of fullerene copolymer nanoballs, which may act as molecule ball bearings, which in turn lead to elastic rolling lubrication.
Lei Hong (School of Mechanical Science and Engineering, Huazhong University of Science and Technology) Guan Wenchao, Liao Daoxun (Huazhong University of Science and Technology)
A novel C60-styrene-maleic anhydride copolymer was prepared with radical polymerization. 50 mg of C60 and 1 g of styrene and 1 g of maleic anhydride were dissolved in 20 mL of o-dichlorobenzene, then was initiated by 200 mg of BPO at 70 ℃ under the protection of Ar for 32 h. The copolymer was obtained as a brown solid. The structure of copolymer was characterized by UV and FTIR. GPC analyses shows that its average molecular weight Mw is 13 000. The copolymer is soluble in THF, DMSO and water. The surface tension of 0.5% of copolymer aqueous solution was determined to be 54.6×10-3 N/m(20 ℃). TEM analyses shows that the copolymer is a kind of water-soluble nanosphere with the average diameter of about 60 nm.
A fullerene styrene maleic anhydride ternary copolymer was synthesized. It is soluble in water and of spherical shape with an average diameter of about 83 nm. As an additive for a base stock (a triethanolamine solution of mass fraction 2%), the fullerene copolymer was able to raise load carrying capacity and reduce the friction coeffient considerably.