预防橡胶木蓝变和霉变的研究

橡胶木极易受到蓝变菌和霉菌的侵害，须进行预防性保护处理。目前我国使用五氯酚钠(NaPCP)控制和防止蓝变和霉变的产生，但自从发现氯代酚类化合物中含有致癌的二恶英类化合物后，此类化合物就逐步被世界大多数发达国家和一些发展中国家禁止使用了。自20世纪80年代开始，环保型防变色剂预防木材蓝变和霉变的研究和开发在国际上开展的十分广泛。本文研究了不同浓度的Antiblu防变色剂预防橡胶木和Parachem、硼类防腐剂加压处理的橡胶木锯材的防变色效果。选取了橡胶木新鲜锯材650根，分为13组，每组50根。其中1组(o组)不用硼防腐剂进行防腐加压处理，也不进行防变色处理，作为试验对照组。4组(a、b、c、d组)不用硼防腐剂进行防腐加压处理，只用防变色剂浸沾处理。另4组(e、f、g、h组)先用硼酸，硼砂防腐剂进行防腐加压处理，再用防变色剂浸沾处理。其余4组(i、j、k、l组)先用Paraehem橡胶木防腐剂进行防腐加压处理，再用防变色剂浸沾处理。其中，a、e、i3组用相对体积质量1．0％的Antiblu 20EC浸沾处理；b、f、g3组用相对体积质量1．5％的Antiblu 20EC浸沾处理；c、g、k3组用相对体积质量2．0％Antiblu 20EC浸沾处理；d、h、l3组用相对体积质量1．5％的Antiblu 20EC 0．125％ Antiborer 10EC浸沾处理。结果表明：无论是未经防腐处理的橡胶木，还是硼类防腐剂处理的橡胶木，用防变色剂进行处理，可有效地防止窑干前橡胶木的蓝变和发霉，有效解决橡胶木的蓝变和发霉问题，保护期可达4周以上。     

橡胶木的防变色试验

通过不同浓度的不同防变色剂分别对未处理和经过硼防腐剂和Parachem防腐剂加压处理的橡胶木锯材进行浸沾处理，对其防变色效果进行了研究。结果表明，无论经过硼防腐剂处理与否，用防变色剂进行短时间（30s)的浸沾处理，均可有效地防止橡胶木的蓝变和发霉，保护期可达4周以上。     

橡胶木防霉防蓝变药剂的现场试验

现场试验的结果表明，F1/F2混剂处理的橡胶木圆盘、单板的防霉及防蓝变效果较F2及五氯酚钠要好。F1/F2及五氯酚钠各制剂处理的板材基本上无霉菌感染及蓝变。在真空加压试验中，0.02?可保持橡胶木板材在气干过程中12天基本不霉变及蓝变，但对白霉的防治效果较差；0.0094?与0.018?混合剂可保持像胶木板材气干时15天不长霉或蓝变，增加F1/F2的浓度可能会在气干时保持更长的时间。     

橡胶木胶合板阻燃技术研究 Ⅳ.橡胶木胶合板的燃烧性质及热性质

通过对橡胶木胶合板与水曲柳胶合板、杨木胶合板、椴木胶合板的点着性、燃烧释热性、火焰传播性、发烟性以及热重曲线的对比,了解橡胶木胶合板的燃烧性质和热性质,并进一步探讨ＷＦＲ作为橡胶木胶合板阻燃剂的处理效果。     

橡胶木胶合板阻燃技术研究Ⅲ.橡胶木阻燃胶合板的吸潮性

采用在相对湿度为１００％的环境中,测定材料因吸潮而增重的方法对６种橡胶木阻燃胶合板吸潮率、药剂吸潮率以及胶合板吸药率为１５％时与未阻燃处理的橡胶木胶合板吸潮率进行了对比和评估。其中磷氮系阻燃剂的吸潮性明显高于ＷＦＲ树脂型阻燃剂。所有阻燃处理的橡胶木胶合板吸潮性均高于未处理的普通橡胶木胶合板。     

Micromorphology of abnormal and decayed xylem in rubberwood canker

Typical symptoms of rubberwood canker found in East Kalimantan, Indonesia, differ from those of conventional rubberwood peach canker. Rubberwood canker showed a conspicuous longitudinal canker with exposed xylem that was discolored and decayed. Bark wounds, resulting from regular tapping, were enclosed within the xylem, and the tissues had become integrated. The characteristics of abnormal and decayed xylem in this rubberwood canker were analyzed by light microscopy and scanning electron microscopy. Xylem in the vicinity of the enclosed bark contained fewer vessels of smaller diameter and shorter length, and significantly wider rays compared with normal xylem. Around the wide growth zones of the canker, axial cells were disoriented and warped toward the canker zones. In view of the separation among cells, and the concentric degradation of the cell walls starting from the lumen surfaces, decayed xylem appeared to be caused mainly by white-rot fungal attack.     

4种防霉剂短期防止橡胶木霉变的初步研究

为筛选高效、低成本、环保型橡胶木防霉剂,采用冷浸法处理新鲜橡胶木试材,分析4种环保型防霉剂TBQ、FB、LA、LB短期防止橡胶木霉变效力及防腐处理前后木材的颜色差异。结果表明:(1)单独采用硼酸/硼砂不能防止橡胶木霉变;采用2%的TBQ浸泡1 h能有效防止橡胶木14 d不发霉;浓度为0.1%～0.2%的FB处理7 d能控制霉斑不超过20%,14 d霉变面积超过40%;浓度为0.05%～0.3%的LA处理7 d能控制霉斑不超过5%,14 d霉变面积不超过30%;浓度0.1%～2.0%LB处理14 d试材霉变面积超过50%,防霉效果较差;(2)LA和LB与硼复配后,能提高其防霉效果,由于LA配比浓度及成本较低,具有潜在的应用前景;(3)防霉防腐处理过程,会导致木材颜色发生一定程度褐变。     

Superheated steam treatment of rubberwood to enhance its mechanical,physiochemical, and biological properties

ABSTRACT

This research was aimed to investigate mechanical properties, color and cell-wall components changes, and durability of pre-dried rubberwood (Hevea brasiliensis) after superheated steam (SS) treatment. Wood samples were treated at different SS temperatures (140–180°C) for 1–3?h. The highest compression strength parallel-to-grain, hardness and impact strength were found for samples treated at 160°C for 3?h (30.7% higher than untreated), at 150°C for 1?h (26.6% higher than untreated) and at 150°C for 2?h (52.6% higher than untreated), respectively. The surface color became darker after each treatment in comparison with the untreated wood. The number of accessible hydroxyl groups decreased and the relative cellulose crystallinity increased with SS temperature, indicating decreased hygroscopicity of the treated wood. Also, SEM micrographs of wood surface showed consistent decrease in starch particles with treatment temperature. Both decay and termite resistances of treated rubberwood improved with treatment temperature. All the analyzes showed that dried rubberwood treated with SS had some improvements in the mechanical properties, decreased hygroscopicity, and increase resistance to decay.     

橡胶原木蓝变及防治方法初步研究

新鲜橡胶原木最易感染蓝变菌而引起木材蓝变。试验结果表明,造材后即用２％ＴＭＯ防霉剂喷涂端面,若在雨季喷药后再涂刷防水ＴＭＯ,一个月内效果良好,适用于鲜橡胶原木的短期保存。     

中国橡胶木加工利用调查

本文简要叙述了中国橡胶木资源、板材防腐与干燥处理，家具及人造板生产等加工利用状况，并对今后开展橡胶木加工利用的研究及推广提出了建议。