Surface grafting of polyethylene fiber for improved adhesion to acrylic resin

Surface grafting of polyethylene (PE) fiber with methyl methacrylate (MMA) and acrylic acid (AAc) were prepared with two-stage method. Functionalization was first carried out in aqueous solution of potassium peroxydisulfate at 80°C. The fiber was then surface grafted with MMA and AAc. Single fiber composite of grafted fibers/Orthocryl^® acrylic resin were prepared and adhesion evaluated with pull-out test. Acrylic matrix was prepared in two methods. In the first method, acrylic powder was bonded together with acetone. In the second, the powder was mixed with liquid monomer to form self-cure material. It was found that in the former case, in which only interdiffusion of polymer chains can occur, MMA-modified polyethylene fiber had slightly higher pull-out strength than AAc-modified fiber. In the latter case, in which chemical reaction occurred, AAc-modified fiber provided much higher pull-out strength than MMA-modified fiber. The difference in adhesion level is discussed.