| From the initial discovery, a new kind of nanomaterial—Carbon Nanotubes(ab. as CNTs) has increasingly caught people's eyes and become hot focus around the world due to its novel physical and chemical properties, significance in basic research and potential application value. However, the CNTs has very high heat-stability and until now there's still not any solvent which can disresolve it well, which limits CNTs for further development and application extremely. According to the character of molecular structure, the CNTs is made up of sp2 carbon atoms, so there are lots of π bonds including π electrons, which can react through π-π action with other molecules containing π electrons, and get chemically modified CNTs.Accordingly, depending on the design of molecule, we have synthesized two kinds of uniformity and steady compound latex containing CNTs, which are CNTs/polyethyl acrylate and CNTs/polybutyll acrylate by the method of latex polymerization, and get two new kinds of CNTs' polymer as CNTs/PEA and CNTs/PBA by breaking the compound latex. And we have synthesized another kind of CNTs' polymer as CNTs/polymethyl acrylic acid(CNTs/PMAA) by the method of solution polymerization, which can be soluble in water.Using FTIR, UV, Fluoresecence, TEM to characterize their configuration and analyze their microcosmic shapes. We found that the CNTs/PMAA polymer has fluorescence property. Our products can also be resolved in water or some ordinary organic solvents. On the one hand, we can get soluble CNTs, which can open a convenient door for other chemists in further research, on the other hand, we can get special functional CNTs and its polymer composite materials. It must drive the rise and development of a series of correlative high-tech industry, which makes CNTs becoming the most promising materials be worthy of the name. Based on the perennial study on water-soluble nanoball of core-and-shell copolymers including C60/C70 lubrication additives made by our group, and the lubrication model of nanoscaled rolling microball, we suppose that chemically-modified CNTs, with firm tubular structure of the CNTs and the grafted soft and elastic macromolecular chains, can also acquire rolling friction from gliding friction. The lubrication properties of the synthesized polymers including the CNTs as lubrication additive when mixed with additive OPZ were evaluated by four-ball test machine, and the conclusions were as follows:When 0.1wt%, 0.1wt%, 0.2wt% adding of the three kinds of additives, the wear scar diameter respectively decreased to 0.339mm, 0.378mm, 0.395mm, which showed preferable anti-wear ability. When 0.2wt%, 0.5wt%, 0.2wt% adding, the PB value increased respectively to 650N, 760N, 600N, which showed fine load-carrying capacity. The lubrication properties directly related to the adding quantity of the products, and excessive adding may lead descending of the lubrication properties. In addition, the industrial evaluation indicated that CNTs/PEA compound latex showed great potential application value and expansive market foreground in cold-rolling industry, when it was used as additive of rolling oil.The typical worn surfaces in four-ball test were analyzed by SEM, the photos demonstrated that when adding the synthesized products as additive, the wear scar obviously became smaller and the friction scratches also became thinner and more shallow, which intuitionistically showed us their fine lubrication properties.However, so far, the study on CNTs used in tribology has not developed in deed, a few research reports just restricted in using CNTs as solid lubricant, or simply dispersed in basic materials to test its lubricate properties. Our works are based on the polymer chemically-modified CNTs, and to evaluate its lubricate speciality as water basic solution additive. Which will provide new ideologies and methods for tribology of CNTs.
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