1991 Volume 48 Issue 2 Pages 61-66
Surface hardness and friction properties of the poly (methyl methacrylate) (PMMA) -monomer system irradiated by low-energy electron beams (EB) are investigated, The hardness of the monomer system irradiated by EB depended on the molucular weight/functionality value. The monomer system with a stearyl group showed a low friction coefficient and the monomer system with a hydroxyl group showed a high value. In the PMMA-monomer system irradiated by EB, the film had intermediate hardness and friction coefficient values, between those of PMMA and those of the monomers irradiated by EB. In the PMMA-monomer with a stearyl group system, the friction coefficient decreased considerably. The results suggest that the concentration of the monomer with a stearyl group increased at the polymer surface and the monomer was polymerized on the surface by EB. The friction coefficient and the contact angle of the polymer surface also depended on the annealing condition before EB irradiation. It was found that the surface properties of cured film are greatly infiuenced by the compatibility of the polymer with the monomer and the polymer therefrom polymerized in the polymer-monomer system.
