Study On Manufacturing Technology Of Medium-density Fiberboard With Malus Mill (apple Tree)

Contradiction between wood supply and demand is getting more and more obvious in China as we are one of countries lacking of forest resource, thus saving existing wood,developing new wood and exploring replacements of wooden products will be long-term main trend for China's wood industry. Malus Mill tree is a new raw material, currently its planting area in China has reached up to more than 18,900 km2 and volume of plentiful waste remains produced by pruning and renewing is as high as 58,000,000 m3 every year. Except man-plant forest, Malus Mill tree becomes a significant wood resource of fiber in our country. Making use of Malus Mill tree not only helps us to find a solution to wasting material in a lot of places, but also relieves of difficult to get MDF raw material.In this paper, the study of materials through the wooden structure on Malus Mill observation, fiber morphology and chemical composition determination, and other common softwood and hardwood timber comparison of Malus Mill, considered wood feasibility of fiberboard.as a raw material. The test of the average length of wood fiber is 0.7 to 1.2mm, shorter than coniferous wood but longer than non-plant fiber. The average width of Malus Mill wood fiber is 14 to 20μm, smaller than coniferous wood, but the average width of the fiber is similar to broad-leaved wood. Overall, Malus Mill wood fiber is similar to hardwood timber, as an excellent raw materials for particleboard and fiberboard manufacturing.The results showed that Malus Mill wood chemical composition of the ashy substance content 0.32 percent, cold-water extract content 6.51 percent, hot-water extract content 7.31 percent,1 percent sodium hydroxide ex-tract content 13.69 percent, benzyl extract content 5.11 percent, lignin content 24.63 percent, poly-pen-tose content 24.11 percent, and a-cellulose content 80.89 percent. Considering all the various angles, Malus Mill wood is more suitable for the production of a plate of raw materials.By DSC, curing agents on the amount of urea-formaldehyde resin curing process,the impact of urea-formaldehyde resin in apple wood fiber in the imposition of the urea-formaldehyde resin curing effects. In this experiment the use of adhesive, by adding NH4Cl and not for the reinforcement of the UF compared to thermal response curve significantly different. The reason is that the accession NH4Cl, with the UF in the hydroxymethyl response form-hexamine, hydrochloric acid and water, thereby reducing the pH value of the UF resin to cure faster. When the chloride content of 1.5%, the lowest temperature curing. When UF resin for the imposition of 12 percent, the best level of the curing resin.Using orthogonal design of the Malus Mill-medium density fiberboard pressing the main process parameters to conduct studies on the various process parameters on the physical and mechanical properties of sheet impact, according to orthogonal test that Malus Mill wood density fiberboard optimum process parameters:pressing pressure of 3.5MPa, pressing time 5 min, the temperature hot-pressing 170℃, the sizing of 12%.Through the medium density fiberboard apple wood veneer veneer of decorative Process, veneer sheets after the board than in the good mechanical properties. According veneer finishes of the two-paste, paste that to stem the product of the system in the surface of good quality and high-performance products. According to orthogonal test, that veneer of the more parameters are as follows:pressing temperature 110℃,pressing time 50s, pressing pressure 1.4MPa, coating of 100g/m2.