Studies On The Surface Photografting Of Polyfunctional Monomer

Photografting (λ > 300nm) of trimethylol propane triacrylate (TMPTA) on the surface of low-density polyethylene (LDPE) film was investigated at room temperature in a mixed solvent of acetone and water, or THF and water, using benzophenone as an initiator. It seems that the polyfunctional monomer could be grafted easily onto the surface, forming cross-linked structure.Precipitation-photografting polymerization took place in the mixture of acetone and water, forming cross-linked microgel grafted on the substrate films. At lower monomer concentration, small particles were observed on the surface of grafted film. With the increasing of monomer concentration, the activity of the grafted chains was confined because of the increased viscosity. Floccules substance appeared on the grafted surface.While using the mixed solvent of THF and water, both the grafted polymer conversion and the rate of photografting polymerization is higher, because of polymer chains were swelled well, and a thin layer of PTMPTA was grafted onto the surface. Water acted as porogenic agent in...