| Abstract: | The role of vacuum ultraviolet (VUV) rays contained in the plasma during plasma‐induced graft polymerization in the pores of a porous high‐density polyethylene (HDPE) substrate was investigated through the separation of the VUV rays from the plasma with LiF, CaF2, and quartz filters. Two characteristic phenomena, the effect of the solvent on the grafting rate and the graft polymerization in the pores of the porous substrate, were observed in the VUV‐induced graft polymerization process. These results provided clear evidence that VUV rays in the plasma played an important role in the formation of grafted layers in the pores of the HDPE substrate. The relationship between the penetration depth of the VUV rays and the distribution of the grafted layer inside the substrate was examined. The calculated penetration depth of the VUV rays (and hence the distribution of radicals) and the distribution of the grafted layer were not consistent. However, this inconsistency could be explained by the fact that the effective density of the radicals that could react with the monomer to grow the grafting polymer was very low because of the steric hindrance of the grafted chains. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2068–2074, 2005 |
