| Fiber conversion of biomass materials and its application in the field of adhesives is a subject studied extensively at home and abroad in the past more than 20 years, but most are still in the laboratory stage, industrialization of technology needs to be improved. Comparison, liquefaction technology of peanut hulls in phenol with phenol high substitution rates, less residue, liquefied under mild conditions, liquefaction speed, preparation of liquefied resin adhesives(PLPF resin for short) shelf life long, low content of free formaldehyde, has some advantages such as water resistance, have a practical basis; But there are poor cold pressing effects, compared with urea-formaldehyde resin high costs, slow curing, low compared with phenol-formaldehyde resin adhesive strength problems. Modification about PLPF resin and therefore, overcome their shortcomings, bio-glue out of the lab into the industry, extended PLPF resin application, is of great significance and practical value.Article PLPF resin adhesive as object, to address PLPF resin costs, water resistance, cold pressing, curing temperature and speed, and other aspects of the issue for the purpose, using reasonable experimental design and modern analysis methods such as using FTIR, DSC, preparation of the adhesive of low formaldehyde adhesives suitable for indoor and outdoor and water resistance of high-strength and high structural adhesives; Systems study on urea copolymer, melamine modifier blend, and effect of preparation process on properties of adhesives, effect of fillers on the adhesive effect of cold pressing, curing agent for adhesives curing speed, and many other effects; Comparative analysis of modified adhesive chemical groups, hot curing characteristics changes before and after, concluded that four species of pertinence of modified resin. The conclusions are as follows.(1) Peanut hulls in phenol liquefaction products modified by copolymerization with urea and orthogonal optimization of formulations prepared by low cost and excellent bonding properties, low free formaldehyde content urea-modified PLPF resin adhesive. FTIR analyses showed that phenolic hydroxyl group directly into the amide structure, urea copolycondensation reaction with the PLPF resin. DSC analysis shows high temperature of the resin, adding home made modifier to lower temperature of resin from 131.5℃ to 122.8 ℃s. degreeModified resin use put the peanuts in hulls, cooked glutinous rice flour, additive of calcium carbonate mixed, cold pressure effect is much improved. Improved multilayer parquet of urea-modified PLPF resin substrate, relevant indicators above the GB/T18103-2000< Engineered Wood Flooring > requirements of the parquet, plank formaldehyde emissions reach E0.(2) According to n(PL+U):n(F)=1:1.5 n(PL):n(U)=1:1.2 n(U):n(F1)=1:2.2, preparation of urea modified PLPF resin bonding strength 0.76 MPa, suppression of the physical and chemical properties of building template meets the requirements of GB/T17656-1999 < Concrete Form Plywood>.(3) Orthogonal test optimizing PLPF resin preparation, 40 min by low temperature reaction time,high-temperature condensation of time 40 min, preparation of adhesive bond strength of reaction temperature 70 ℃ about 1.03 MPa.(4) PLPF with melamine resin modifier at the mass ratio blending preparation of modified 7:3 resin, pressed poplar plywood for adhesive strength test of 1.133 MPa, outdoor structure plywood to meet the requirements. FTIR and DSC analysis showed that the modifier PLPF resin and cured in the process a certain cross-linked, but also showing PLPF resin and heat-curing characteristics of different.(5) Modified PLPF resin raw materials cost ranges from 1400 to 2133,uses different bonding properties, wide application range, has a competitive advantage. |
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