密实型杨木单板层积材制造技术

摘要

This paper introduces the present study and utilization of Laminated Veneer Lumber (LVL) and dense LVL. It mainly covers the investigation on manufacture technology of dense Poplar LVL in impregnation way ,in which Poplar veneers were impregnated with low-molecular-weight water-soluble phenol-formaldehyde resin. The results indicated that :under the condition of equal resin consumption , the properties of dense LVL manufactured in impregnation way were better than those of manufactured in resin spreading way, 24h TS of the former decreased by 24% than the latter, bond strength increased by 16%, MOE and MOR increased by 20. 17% and 44. 76% respectively, while the density of two kinds of LVL manufactured in different ways were close; when impregnation way was used, as the resin amount absorbed increased, the density of dense LVL in-creased, 24h TS decreased, the bond strength increased at first and then remained stable, MOE and MOR were improved significantly first, then decreased afterwards, and MOE and MOR came to the peak value, reached 15.34GPa and 135.31MPa respectively at absorbed resin content of 168. 1%. The great physical and mechan-ical properties of dense LVL meet the requirement for construction use, so it is a potential structure material.%介绍了单板层积材、密实型单板层积材在国内外的研究和利用概况.探讨了采用低分子量酚醛树脂浸渍处理杨木单板的方法制备杨木单板层积材的生产技术.结果表明:施胶量相当时,浸渍方式与涂胶方式生产的单板层积材相比,密度相当,吸水厚度膨胀(24hTS)降低了24%,胶合强度提高了:16%,弹性模量(MOE)和静曲强度(MOR)分别提高了20.17%和44.76%.采用浸渍树脂方式生产的密实型强化杨木单板层积材随着吸药量的增多,密度增大;24hTS减小;胶合强度随着吸药量的增加先增大而后趋于平稳;MOE和MOR先增大后减小.当吸药量为168%时,MOE、MOR达到最大,分别为15.34GPa和135.31 MPa.密实型强化单板层积材能够满足建筑和木结构等结构材要求,具有良好的发展空间.