| Wood-based materials are main raw materials for wood furniture and indoor decoration.Their surfaces are mainly decorated with coating,resin-impregnated paper,and artificial veneer to improve appearances,increase values,and protect base composites.However,these surface decorations can’t meet the diversly and personally artistic demands of customers any longer because their appearances are monotonous and hard to re-change.The green surface decorating strategy of wood-based materials using fabrics with abundant decorating elements and good personally artistic expressions can overcome above-mentioned disadvantages.Aimed at the main bottle issues of surface decoration of wood-based materials with fabrics,this study focused on the synergistic enhancing modification and their interactions of effective biomassbased adhesive,by which lay instructive theoretical foundations for the modifications and applications of biomass-based adhesive for fabric-decorated wood-based materials.It mainly includes:According to the technological and performance demands of fabric decoration of woodbased materials,it optimized the suitable adhesives and their matched bonding technologies for three fabric-decorations of hot pressing,cold pressing and ironing based on the evaluations of curing characteristic,bonding property,environmental safety,and adhesive penetration on fabric.A novel ironing decorating technology was developed,which resulted in fast-curing of aqueous polymer-isocyanate(API)adhesive and higher bonding properties and adapted to the personalized artistic surface decorations of wood-based materials by customers themselves at home.It ascertained that soybean-based adhesive is the most preferable adhesive for the fabricdecorated wood composites via hot pressing while API adhesive for surface decoration via cold pressing and ironing.However,these two preferable adhesives for fabric-decorated woodbased materials remain some bottlenecks unsolved such as resin penetration by hot pressing,short pot life of API adhesive,and high adhesive cost,which could not be overcome by optimal decorating and bonding technologies.Facing with easy adhesive penetration,poor mildew resistance and high cost of soybeanbased adhesive for fibric decoration by hot pressing,a synergistic modification strategy was proposed by the combinations of filler blocking adhesive penetration,inorganic hybridization,mildew inhibition by converting protein,and mildew prevention by the assistance of HCOONa.Based on the effects of 7 filler species,kaolinite dosage,epichlorohydrin ratio,crosslinker MPA concentration,and HCOONa levels on the structure,performance,and cost of soybeanbased adhesives for fabric decoration,the synergistic enhancing mechanisms of soybean-based adhesive were revealed.The improved bonding properties,elimination of resin penetration and decrease adhesive cost were attributing to the formation of compact inorganic-organic hybridization structure via intercalation and the blocking effect of low-cost inorganic fillers on loose fabric structures.It also ascertained that the cost-efficient synergistic interactions for improving mildew resistance of soybean-based adhesive are attributing to the sufficient conversion of mildewing primary amines of soybean proteins into mildew-tolerant secondary amine linkages via improving the crosslinking reactivity of MPA resin synthesized with higher epichlorohydrin ratio,and the further assistance by the green and low-cost HCOONa.Consequently,a synergistically modified soybean-based adhesive with good bonding property(dry and boiled peeling strength of 1.37 k N/m and 0.86 k N/m,respectively),less adhesive penetration,desired mildew resistance,and reduced adhesive cost by 12% was fabricated,which adapts to the surface hot-pressing decoration of most wood-based materials and fabrics.In view of short pot life and high cost of traditional vinyl-based API adhesive for surface decoration,a novel approach for preparing water-based polymer of API adhesive by dissolving thermo-chemically modified wheat flour and 0.3% HCOONa in 10% PVA solution,by which fabricated a cost-effective wheat-based API adhesive for most fabric decorations of woodbased materials with good bonding properties(dry and boiled peeling strength of 0.86 k N/m and 0.68 k N/m,respectively)comparable to commercial vinyl-based API adhesive,long pot life for 10 h,good mildew resistance,and reduced adhesive cost by 45%.Based on the chemical structure,crystallinity,active group content,dispersing stability,viscosity,pot life and bonding property of wheat-based API adhesives,the synergistic enhancing mechanisms of thermo-SDS-modified wheat-based API adhesive were revealed.The improved water and mildew resistances were mainly attributing to the promotion of SDS-thermal synergistic interactions to unfolding and crystallinity decreasing of wheat,which were benefical for sufficient wheat-polyisocyanate crosslinking and wheat protein-starch Maillard reaction that resulted in more crosslinking density and sufficient conversions of mildewing primary amines of wheat proteins into mildew-tolerant secondary amine linkages.Meanwhile,SDS-thermal synergistic interactions also promoted the complexing of SDS and unfolded wheat that could inhibit the reaction of polyisocyanate with water,by which prolonged the pot life of wheatbased API adhesive.Additionally,it exhibited some examples of fabric-decorated wood furniture,by which verified that the optimal thermo-SDS/0.3%HCOONa modified wheatbased API adhesive and ironing bonding are suitbale for domestic artistic decorations of wood furniture and indoor wood decorative materials by customers themselves. |
