| In this paper, LPF resin and Eucalyptus were used to prepare OSB, The first study on LPF resin synthesis, physicochemical properties, wetting properties, and find out the bagasse lignin content range. Then with the method of single factor optimization of bagasse lignin content and molar ratio (F/P) to optimize the performance of the resin. On the basis of this, the LPF resin was introduced into the conventional process and the impregnation process of Eucalyptus OSB. And through the single factor method, Eucalyptus shaving thickness, OSB in surface layer and core layer ratio, LPF resin solid content are screened in the preparation process of OSB, which was optimized by orthogonal test, and in order to obtain a better preparation process of Eucalyptus OSB. The main conclusions of this paper are as follows:(1) In the synthesis of LPF resin, the bagasse lignin content range was 25%-175%, the molar ratio (F/P) range wasl.5-1.8. Better synthesis process of the resin is:the bagasse lignin content range is 50%, the molar ratio (F/P) is 1.8. Plywood prepared by the method, the dry-plate bonding strength is 1.65MPa, wet bonding strength up to 1.36MPa, more than I class standards board, the formaldehyde emission is 0.17mg/L up to Eo level.(2) The higher the bagasse lignin content and the temperature is in the LPF resin, The worse the surface wettability of Eucalyptus shavings is. the surface free energy of Eucalyptus shavings is mainly components of Lifshitz-van der Waals. The acid and base components of Lewis accounted for only about 9% of the free energy. The base component is about 110 times of the acid component in the acid and base components, so it is a basic characteristic of the material.(3) Eucalyptus shaving thickness, surface layer and core layer ratio had a significant effect on the performance of OSB, the shaving thickness can be selected from 0.7mm to 1.7mm, the core layer ratio can be selected from 60% to 70%. When the shaving thickness is 1mm and the core layer ratio is 60%, the performance of OSB is better.(4) In the conventional preparation process of OSB, the factors affected its performance from primary and secondary are:hot pressing temperature> hot pressing time> resin content; The conventional process optimization scheme parameters are:hot pressing temperature is 160℃, hot pressing time is 720s, resin content is 14%. OSB prepared with the scheme meets the standard of OSB/4, the internal bonding strength is 0.86MPa, wet internal bonding strength is0.56MPa, MOR (//) is 63.13MPa, MOR ((?)) is 50.65MPa, MOE ((?)) is 5184.93MPa, MOE (//) is 7237.98MPa,24h soaking rate is 5.53%, the density is 0.64 g/cm3.(5) In the impregnation preparation process of OSB, The resin solid content has significant effects on the performance of OSB. When the resin solid content is 25%, the performance of OSB is better. The factors affected its performance from primary and secondary are:hot pressing temperature> hot pressing time> impregnation time. The impregnation process optimization scheme parameters are:hot pressing temperature is 165℃, hot pressing time is 750s, impregnation time is 30min. OSB prepared with the scheme is up to the standard of OSB/4, the average of the internal bonding strength is 0.96MPa, wet internal bonding strength is 0.68MPa, MOR (_L) is 54.62MPa, MOR (//) is 74.13MPa, MOE (_L) is 5641.63MPa, MOE (//) is 9753.27MPa, the density is 0.64 g/cm3,24h soaking rate is 2.27%.(6) Compared with the optimized OSB conventional process and impregnation, in the impregnation process, the internal bonding strength increased by 11.63%, wet internal bonding strength increased by 21.43%, MOR (_L increased by 7.84%, MOR(//) increased by 17.42%, MOE(_L)increased by 8.81%,MOE (//) increased by 34.76%,24h soaking rate decreased by 59.25%, its resin content is is 19.11% less than the resin content of the conventional process, its heat transfer performance is worse than the conventional process. |
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