【作者】 张颖；

【导师】 于志明；

【作者基本信息】 北京林业大学 ， 木材科学与技术， 2010， 硕士

【摘要】 为了优化施胶工艺,降低成本,提高生产实践中胶黏剂的利用率,本文建立了全新的量化胶合板施胶效果表征参数体系,采用GluScan胶黏剂扫描系统对单板以及热压后剥离单板表面施胶效果进行检测分析。通过改变涂胶量,对其进行了宏观量化以及微观表征的评价,并探讨了胶合板力学性能与表征参数之间的关系,建立表征方程等。结论如下：(1)胶黏剂覆盖率、胶滴尺寸和施胶均匀度可以科学准确地评价胶合板上胶黏剂的施胶效果。GluScan胶黏剂扫描检测系统能快速、准确地测量各参数,表征胶合板表面胶黏剂分布状况。(2)胶合板上胶黏剂覆盖率随着施胶量的增加而增加,胶滴尺寸较一致,胶黏剂在胶合板表面的分布趋于一致。含水率、面粉的加入以及胶黏剂在单板的松面和紧面的涂布均对胶黏剂的分布状态有一定的影响。(3)热压过程可以改变胶黏剂在单板表面的分布情况,胶黏剂覆盖率与胶滴长宽方向尺寸随之增加,且紧面涂胶胶黏剂分布变化更均匀。(4)施胶效果决定了胶合板的力学性能。施胶量在一定范围内的增大有助于提高胶合板的力学性能。表面粗糙度对其也有一定影响,热压单板胶合强度随松紧面表面粗糙度的降低而增加,且紧面表面粗糙度较松面低；热压后表面粗糙度较热压前低。(5)胶黏剂微观分布规律与宏观分布规律一致。导管内有明显“胶钉”产生。在涂胶量为100 g/m2至160 g/m2时,胶合强度(y)和胶黏剂覆盖率(x)之间的关系为：y=0.5731Ln(x)-1.2746, R2=0.8033,该方程仅表明两者之间的关系。(6)采用固含为54%、粘度13-15 mPa·s、摩尔比1.02的三聚氰胺改性脲醛树脂胶,在单面涂胶量为100g/m2时,单板表面覆盖率达到34.3%,热压后板材表面覆盖率达到38.5%,热压后胶合强度达到国标要求。更多还原

【Abstract】 The purpose of this study is to optimize the resin application process in order to reduce costs and improve resin efficiency. In the study, a new parameter characterization system was developed to evaluate resin application effect by using GluScan to measure the properties of veneer and the stripped veneer after hot pressing resin application process. Macro-quantification and micro-characterization evaluation was made under different resin volumes, the correlation between the mechanical properties of the plywood and characterization parameters was discussed and a characterization equation was established.Results suggested:(1) Resin coverage, resin droplet size and resin distribution uniformity could be scientific parameters to evaluate resin effet on plywood. All these parameters were measured by GluScan to indicate resin distribution on plywood surface.(2) Resin coverage increased while resin volume increased Resin distribution was tending to uniformity while droplet size was relatively uniform. Moisture content, flour added and resin deposition on both sides of the veneer influenced resin distribution to a certain extent.(3) Hot pressing influenced resin distribution on veneer surface:resin coverage and resin droplet size increased and resin distribution variation on the tight side tended to be more uniform.(4) Resin application effect determined the mechanical properties of the plywood. Increase of resin volume in a certain range contributed to the improvement of the mechanical properties of plywood. Surface roughness worked too:bonding strength of hot-pressed veneer decreased while surface roughness of both sides decreased; surface roughness of the loose side was lower than the tight side and surface roughness was lower after hot pressing.(5) Micro-and macro-patterns of resin distribution tended to be similar. Obvious "plastic nails" were found in the resin tube. When resin volume was between 100 g/m2 and 160 g/m2, the relationship between bonding strength (y) and resin coverage (x) was:y=0.5731Ln(x)-1.2746, R2=0.8033.(6) Resin used in the study was MUF with solid content of 54%, viscosity of 13-15mPa·s and mole ratio of 1.02. When surface resin volume was 100 g/m2, surface resin coverage was 34.3% and 38.5% after hot pressing. Bonding strenth after hot pressing meeted the national standard.更多还原