Abstract: In this study, a kind of surface modifiers was synthesized from isocyanate and aliphatic alcohol and was used in poly(vinyl chloride) based woodplastic composites(WPC). After treated with 3 % surface modifier, the surface water contact angle of wood flour increased to 146.0°, and the tensile strength of WPC increased by almost 32.6 % and the elongation at break increased by more than 42.1 %. The plasticizing time of WPC decreased from 57.5 s to 46.7 s, the equilibrium torque decreased from 24.7 to 18.2 N·m, and the plasticizing temperature decreased from 147.3 to 140.4 ℃. In addition, the longer the carbon chain length of aliphatic alcohol, the better the surface modification effect of the surface modifier.

Key words: surface modifier, isocyanate, poly (vinyl chloride), wood flour