Response surface optimization based on freeze-thaw cycle pretreatment of poplar wood dyeing effect

To improve the permeability of dye solution in wood, poplar was pretreated by freeze-thaw cycle. The effects of three parameters, such as freezing time, thawing time and circulation times on the dyeing effect of pretreated poplar were investigated by single factor method. On this basis, pretreatment conditions were optimized by response surface methodology. The optimum conditions of this treatment were freezing time of 11.9 h, thawing time of 7.2 h and two cycles. Under these conditions, the dye uptake and chromatic aberration of the treated wood were 25.77% and 21.14%, respectively, which were close to the theoretical predicted values. The results showed that freeze-thaw cycle pretreatment could effectively improve the permeability of poplar and enhance the dyeing effect of wood.