Effects of wax and dimethyl silicone oil mixed impregnation on dimensional stability of two hardwoods
In this experiment, cocobolo (Dalbergia retusa Hesml.) and African padauk (Pterocarpus soyauxii) specimen were selected before treating with wax, wax + 20% dimethyl silicone oil, wax + 40% dimethyl silicone oil at 120°C for 3 h and 6 h respectively. The weight gain percentage (WPG), radial swelling coefficients (RS), tangential swelling coefficients (TS), chemical composition and strength of hydroxyl groups were investigated. The results indicated that three factors affect dimensional stability, including the impregnation time, tree species and ratio of wax /dimethyl silicone oil. The degree of a melioration in the dimensional stability increase as the impregnation time increase from 3h to 6h. The effect of the impregnation on the dimensional stability of the African padauk was better than that of the cocobolo. Wax+ 40% dimethylsilicone oil was the optimal condition in this study. Wax and dimethylsilicone oil mixed impregnation can improve the dimensional stability to a certain extent, which provides a new idea for the wood modification.