Study On Konjac-polysaccharide Wood Adhesive

Konjac-polysaccharide was used as main raw material in this paper. The important factors of influence on KGM oxidized modification were studied and the preparation process were got in the research.Then the Oxidized Konjac Glucomannan, carrageenan and xanthan gum were remixed.According to analysis model, the optimum proportion region was determined. This paper utilized molecular simulation technology given theory verified on the basic of experiment, wage molecular simulation with analysis between Konjac-polysaccharide wood adhesive and cellulose, which is the main components of wood. The research results are specified as follows:1.The single factor means and orthogonal array design methods experiment was adopt to research the fabrication process of modified Oxidized Konjac Glucomannan. Then the optimum technological parameters and performance index were obtained in the research.This paper chose eight major factors,which of them are affecting the performance of the Oxidized Konjac Glucomannan.We found the optimized conditions of the craft is: Konjaku Flour at 4.5g,distilled water at 300mL,reaction temperature at 50℃, pasting time at 40 minutes, swelling time at 2h,H2O2(30%) dosage at 1mL, oxidization time at 40 minutes, NaOH(1mol/L) dosage at 3mL,pH value at 6.5.The modified Oxidized Konjac Glucomannan viscosity at 4900mPa·s, shear strength at 4.7MPa, peel strength at 5.9Nk/m,initial adhesion at 87g/cm~2.2.Quadratic general rotary unitized design were used to do optimum combination of Oxidized Konjac Glucomannan, carrageenan, xanthan gum. According to analysis model and a established digital model about three indexes and all the factors, the optimum proportion region is determined. Oxidized Konjac Glucomannan: carrageenan: xanthan gum=48-51:39-42:10-13.You can choose different ratio according to the requirement. The three adhesive showed well synergy with each other. When Oxidized Konjac Glucomannan: carrageenan: xanthan gum=50:40:10, the Konjac-polysaccharide wood adhesive is milkiness-colored viscous liquid. The Konjac-polysaccharide wood adhesive viscosity at 5870mPa·s, shear strength at 5.68MPa,peel strength at 6.25Nk/m,transparence at 0.192, gelling properties at 1.75%,gel strength at 178g/cm~2, storage period at six months.3.The research constructed the stability interaction system of Oxidized Konjac Glucomannan, carrageenan and xanthan gum by using soft HyperChem7.0.It also simulated the stability interaction system of Konjac-polysaccharide wood adhesive and cellulose by using simulated soft HyperChem7.0.It forecasted the action sites of Konjac-polysaccharide wood adhesive and cellulose.The former action sites were Konjac-polysaccharide wood adhesiveO(2),O(5),O(6)and carrageenan O(6),the latter action sites were Konjac-polysaccharide wood adhesive O(2),O(5),O(6)and cellulose hydroxy,carbonyl.4 The results show that when specimen soaked in thermostatic of 25 degrees for 3days,the shear strength and peeling strength is keeping upwards of 85%.The adhesive has strong thermostatic water-resistance.The shear strength and peel strength of specimen keep upwards of 90% at temperature 35℃,45℃,55℃and 65℃, have relatively obvious decreased at temperature 75℃,weaker at temperature 85℃.But Konjac-polysaccharide wood adhesive do not have high temperature resistant. Its normal temperature is under 65℃.At normal temperature(25±3℃),sealing the Konjac-polysaccharide wood adhesive, measure its viscosity,shear strength and peel strength after 0d,15d,30d,60d,120d,180d.The experiment results show performance indexes can be keeping in the range of requirement.It possesses good storage stability.