Study On Technology Of Flame-retarded Medium-density Fiberboard With Environmental Concern

Medium-density fiberboard (MDF) is often used in many aspects such as indoor decoration, furniture manufacture and building. It and people's life have many affinities. The paper mainly studies on the technology of producing flame-retarded MDF with environmental concern using two new-fashioned scientific research fruits: innocuous and environmental concerned flame-retardant and BL-formaldehyde absorptive reagent, and has made ideal results. Use technological instrumentality to manufacture fiberboard with environmental concern and flame-retardarce properties, which is not only a kind of technological innovation and practice, but also a contribution to people, enterprises and society. It has great social and economic benefits. This will inaugurate a vast prospect in the utilization of MDF, and make up the deficiency of its manufacture. The study is of important theoretical value and practical significance.The research firstly digests, absorbs and innovates the overseas technique, then gains two scientific research fruits: innocuous and environmental concerned flame-retardant and BL- formaldehyde absorptive reagent which are used in MDF afterwards through lots of ameliorations, experiments and productive trials. Utilize orthogonal experiment design and single factor experiment to analyze the technology. With the help of oxygen index apparatus, formaldehyde apparatus, X-ray diffraction instrument, Fourier transform infrared spectroscopy(FTIR), environment scanning electron microscope(ESEM), thermogravimetric analyzer-thermal analyzer(TG-DGA) and interrelated experiment measures, the following main results are obtained.1 .Under the function of special catalyst, utilize phosphoric acid and urea to prepare innocuous and environmental concerned flame-retardant and BL-formaldehyde absorptive reagent; Then through lots of experiments and optimized amelioration, we find the reasonable technology and actualize their industrialization produce through improving upon stainless steel reaction kettle properly. They are different in proportion of reactants, dosage of catalyst, physical and chemical character and efficacy. They are difference fromgeneral ammonium polyphosphates in raw materials, produce condition, produce equipment, efficacy, product form and molecular formula.2.Innocuous and environmental concerned flame-retardant is a kind of expansible, nitrogen-phosphorus series liquid reagent that has many virtues such as a high concentration, environmental concern, innocuity one reagent with two functions, low cost, easiness to produce and use. Because it has certain influence on urea-formaldehyde resin, it must use and compute dividually. In the lab, after dispose fiber with the retardant firstly, dry to 4% moisture content; Then dry to 8%~10% moisture content in ten minutes under 115°C and ventilation after spraying urea-formaldehyde resin; At last spreading forming, prepressing, hot pressing and testing. The optimal technology parameters of making flame-retarded MDF with environmental concern in lab are 13% environmental concerned flame-retardant spread, 10% glue spread, 160±5°C hot pressing temperature, 45s/mm hot pressing time and four phases to unload press. The factors are glue spread, hot pressing temperature, environmental concerned flame-retardant spread and hot pressing time in influence sequence. The density of board is 80 tape. The physical and mechanical quality of the board reaches the standard of national excellent level board on MDF, maximal internal bond strength 0.66MPa and maximal static bending strength 32.04MPa. Formaldehyde emission is more less than the demand of Ei level(≤9mg/100g), the minimal value is 0.53mg/100g. Weight loss rate of combustion is about 7%. Oxygen index is about 50, exceeds the value 48 of unburnable MDF, has a small quantity of smoke and can't burn when the fire extinguishes. This solves the problem of environmental concern and flame-retardarce radically, has a good sustainability due to whole retardarce disposal.3.BL-formaldehyde absorptive reagent is a kind of wate...