Effects of Recycled Materials on the Properties of Wood Fiber-Polyethylene Composites--Part 2: Effect of a Compatibilizer on the Wettability of Birch Plywood and Polyolefins‪.‬

Abstract This study examined the effects of a compatibilizer on the wettability of birch plywood and polyolefins. The compatabilizer was a low molecular weight emulsion type maleated polypropylene (MAPP), Epolene E-43. The polyolefins investigated included low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and polypropylene (PP). For E-43 treated wood surfaces, contact angles among four wetting liquids were in the order of phenol formaldehyde (PF) urea formaldehyde (UF) isocyanate (ISO) distilled water. Contact angles increased upon addition of E-43, then decreased as concentrations further increased for UF, PF, and ISO. Among the three polyolefin polymers, the contact angles of PP, either wetting with various concentration of E-43 or with various wetting liquids, showed the highest value but was less sensitive to changes in E-43 concentration. For all four wetting liquids, their contact angle ratings for different plastic types all followed the sequences of PP LLDPE LDPE and distilled water UF PF ISO.