The Preparation Of Environment-Friendly Waterproof Fiberboard Based On Acrylic Modified Fluid Wax

With the improvement of living quality, people are paying more and more attention to environmental protection in daily life. Because of the demand of fiberboard products in the market, the low carbon processing technology of fiberboard attract more and more attention of the researchers. Self-bonding technology is one of the ideal methods. On the premise of environmental protection, the market also demand fiberboard with high dimensional stability. The waterproof performance of fiberboard has important influence on the quality of the products. The aim of the research is to develop a kind of fiberboard waterproof agent with good application results and to explore the influence on fiberboard products with adding different types of waterproof agent so that to improve the waterproof performance and mechanics properties of fiberboard products and to broaden its application fields. Therefore, it is an important research direction in fiberboard production.In this study, at first, we use monomer acrylic acid as modifying copula, use K2S2O8 as initiator and use OP-10 as emulsifier to modify the PFAA waterproof agent which is manufactured by liquid paraffin. We use ammonium lignosulfonate which comes from pulping liquid waste instead of traditional aldehyde resin agent as adhesive. And then have physical mechanics analysis and instrument analysis for two kinds of environment friendly waterproof fiberboard which is respectively added with PFAA and PF to determine the optimal fabrication process of PFAA and the best dosage of it in fiberboard. And compare the performance of the two kinds of waterproof agent. At last, we evaluate the influence of the environmental friendliness of medium density fiberboard products which are added with PFAA using GaBi6.0. Through the study, the results are as follows:(l)We conducted single-factor experiments to determine the optimal fabrication process of PFAA, the comparatively good technological parameters are:the dosage of emulsifier is 7%, the stirring speed is 1000r/min, the emulsifying temperature is 85℃, the emulsifying time is 50min. Then we conducted orthogonal experiment to further determine the optimal fabrication process, the comparatively good technological parameters are: the dosage of monomer acrylic acid is 20%, the emulsifying time is 4h, the emulsifying temperature is 80℃, the dosage of K2S2O8 is 0.5%, the stirring speed is 1000r/min.(2)Using the fiberboard which add no waterproof agent as blank control, we respectively analyze the physical and mechanical properties, the contact angle, the functional groups, the cellulose crystallinity and morphology of fiberboard with different dosage of PFAA and PF so that to conclude the effects that different dosage of PFAA and PF has on the dimensional stability of the fiberboard. Results show that compared with the fiberboard that added with PF, it has better properties that added with PFAA.When the PFAA content is 5%, the medium density fiberboard has best physical and mechanical properties and comparatively good dimensional stability. The possible reason is that the carboxy groups that introduced by liquid paraffin grafting with acrylic acid monomer esterificate with hydroxyl groups which come from wood fiber and ammonium lignosulfonate. The PFAA are combined with fiber adequately, with the dosage of the PFAA increasing, the residual part of carboxyl without reaction which is hydrophilic that lead to the dimensional stability of the fiberboard getting worse. Liquid paraffin and the fiber is physical contact, there is a loss in the hot pressing process, and maybe a small amount of liquid paraffin infiltrate into the wood fiber so that the waterproof performance is not good.(3)We evaluate the influence of the environmental friendliness of medium density fiberboard products which are added with PFAA using GaBi6.0.Results show that ammonium lignosulfonate has the greatest influence on the environment, which is followed by fiber preparation, PFAA fabrication, mat formation, post processing, transportation and diesel fuel production. The environmental impact of forest cultivation is negative because the trees absorb CO2 which is good for the environment. Photochemical ozone generating potential has the greatest impact on the environment with the fiber board during the manufacture of fiberboard products, which is followed by environment acidification and global warming. The percent are 44.9%,35.17% and 13.92%.