Key Preparation Technology Of Bamboo Oriented Strand Board

As a natural,renewable,green,and environmentally friendly biomass fiber material,bamboo has the advantages of high strength,short growth cycle,and is widely used in various industries.For China,it is the most important country in the world to produce bamboo,and bamboo is a very beautiful and unique resource with excellent utilization value.Therefore,this article explores how to efficiently utilize bamboo in various forms,It is imperative to promote the development of the bamboo industry.This paper discusses the key preparation process of bamboo oriented strand board(BOSB),mainly including the combination of bamboo particle morphology,the hot pressing process of three layer bamboo oriented strand board,and the influence of five layer bamboo oriented strand board hot pressing curve.This paper mainly studies the following contents:(1)The effects of different morphological combinations of BOSB on the mechanical properties of BOSB were discussed.BOSB was prepared with three different forms of bamboo shavings and their combinations.The BOSB prepared with B/C composite bamboo shavings had the highest static bending strength,while the BOSB prepared with A/C composite bamboo shavings had the best elastic modulus,and the BOSB prepared with C single bamboo shavings had the lowest water absorption thickness expansion rate;The shape of bamboo shavings has a significant impact on the physical and mechanical properties of BOSB.Because of its good bending strength and plasticity,the larger bamboo shavings can effectively improve the strength of the board when preparing BOSB,but there will be gaps between the shavings due to "bridging";The small and fine particle has good fluidity and large effective bonding area,so the BOSB has good stability but poor toughness;The preparation of BOSB and the addition of small shavings as auxiliary fillers can improve the mechanical properties of single use of large or small shavings.(2)Through orthogonal analysis,the effects of hot pressing pressure,hot pressing time and hot pressing temperature on the static bending strength,elastic modulus,internal bonding strength and 24 h water absorption thickness expansion rate of three-layer BOSB were investigated.The analysis shows that when the hot pressing pressure is 1.5MPa,the hot pressing time is 6min,and the hot pressing temperature is 160 ℃,the physical properties of BOSB are optimal.(3)The effects of hot pressing process with different hot pressing curves on the static bending strength,elastic modulus,internal bonding strength and 24 h water absorption thickness expansion rate of five-layer BOSB were discussed.Under the condition that the hot pressing pressure,hot pressing time and hot pressing temperature are consistent,three different hot pressing curves are used for the test,namely,stepwise pressure rise and pressure drop,intermittent exhaust and gradient pressure drop.The results show that the optimal hot pressing process curve under the same hot pressing condition(hot pressing pressure: 4MPa,hot pressing time: 20 min,hot pressing temperature: 160 ℃)is gradient pressure drop.(4)Through the best particle selection obtained in Chapter 2,the three-layer BOSB and three-layer OSB meeting the standard were successfully prepared by the best hot pressing process(hot pressing pressure: 1.5MPa,hot pressing time: 6min,hot pressing temperature:160 ℃)of BOSB(13mm)in Chapter 3;Five-layer BOSB and five-layer OSB that meet the standards were successfully prepared by the best hot pressing process(hot pressing pressure:4MPa,hot pressing time: 20 min,hot pressing temperature: 160 ℃,gradient decompression hot pressing curve)in Chapter 4 BOSB(25mm);By comparing and analyzing its physical and mechanical strength,it was found that BOSB is superior to OSB in terms of mechanical strength and resource utilization.