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31.
Highly filled systems prepared by compression molding of Hevea brasiliensis woodflour filled polybenzoxazine composites with high mechanical properties and reduced water uptake has been developed. The effects of percent filler content and particle size of woodflour on the obtained composite's properties were examined. The low melt viscosity of BA‐a type polybenzoxazine allows substantial amount of woodflour to be easily incorporated into the composites. The results showed that mechanical properties from dynamic mechanical analysis and flexural test at filler content below the optimum filler packing show approximately linear relationship with filler loading. The outstanding compatibility between the woodflour and the polybenzoxazine matrix is evidently seen from the large improvement in the composite's Tg and char yield. Scanning electron micrographs of the composite also reveals substantially strong interface between the woodflour filler and the polybenzoxazine matrix. Water absorption of the composites is greatly reduced with increasing the amount of polybenzoxazine due to the inherent low water absorption of the matrix. The polybenzoxazine is; therefore, a highly attractive candidate as high performance lignocellulosic binder or adhesive and other related applications. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1240–1253, 2006 相似文献
32.
对蒙脱土进行有机改性制得有机蒙脱土(OMMT),并制备了聚氯乙烯侑机蒙脱土/木粉(PVC/OMMT/WF)纳米复合材料。采用硅烷偶联剂对木粉表面进行改性,有效提高了聚氯乙烯/木粉(PVC/WF)复合材料的力学性能,其中加入1.5%(质量含量,下同)硅烷偶联剂可使复合材料的冲击强度和拉伸强度分别提高14.8%和18.5%。研究了OMMT的加入对木粉改性前后的PVC/WF复合材料力学性能、耐热性能及阻燃性能的影响,结果表明,木粉未经改性时,OMMT加入无助于PVC/OMMT/WF复合材料力学性能的提高;木粉用硅烷偶联剂改性后,添加少量的OMMT,可使PVC/OMMT/WF复合材料的冲击强度和拉伸强度明显提高。研究表明,添加OMMT可显著延迟复合材料的点燃时间,燃烧残余率也明显增加,OMMT是PVC/WF复合材料的高效阻燃剂。 相似文献
33.
34.
木/塑复合材料的发展趋势 总被引:15,自引:0,他引:15
本文介绍了木/塑复合材料的生产技术及应用状况,指出其与原木材料和纯塑料制品的性能对比优势,开发厂商的开发及发展动态。 相似文献
35.
木材液化及其在高分子材料中的应用 总被引:9,自引:1,他引:9
木材通过液化可转化为具有反应活性的液态产物,进一步反应可以制备胶粘剂、聚氨酯材料等新型高分子材料。文章从方法、机理以及其产物在制备高分子材料等方面对木材液化的研究进展进行了评述。 相似文献
36.
In Yang Monlin Kuo Deland J. Myers 《Journal of the American Oil Chemists' Society》2006,83(3):239-245
Chromated copper arsenate (CCA), an arsenicbased wood preservative, is toxic to human health and the environment. Although
CCA is stable in seasoned wood, there are potential dangers during CCA manufacture, lumber treatment, and waste disposal.
This research was conducted to study the effectiveness of soy products to replace toxic chromium and arsenic compounds in
wood preservative formulations. Three soy product (Arpro 2100, HM 90, and Supro 760) were used as fixative agents in preservative
solutions containing anhydrous CuSO4 and Na2B4O7·10H2O. The decay resistance of treated wood blocks was measured by a soil-block culture method. Despite the large molecular sizes
of copper-protein and copper-boron-protein complexes, southern pine sapwood was treatable with these preservative formulations.
Wood samples treated with >6 kg°m−3 CuSO4 and 7.5 kg·m−3 soy product, and subsequently leached for 3 d and exposed to the decay fungus Gloeophyllum trabeum (Fr.) Mur., sustained only 0.5% weight loss over 12 wk. Wood samples needed 40 kg·m−3 CuSO4 and 50 kg·m−3 soy protein to resist the copper-tolerant decay fungus Postia placenta (Fr.) M. Lars. & Lomb. These results suggest that soy-based wood preservatives can prevent wood products from fungal attack
and can replace CCA. 相似文献
37.
Mechanical properties of wood plastic composites (WPCs) manufactured from sawdust and virgin and/or recycled plastics, namely high density polyethylene (HDPE) and polypropylene (PP), were studied. Sawdust was prepared from beech industrial sawdust by screening to the desired particle size and was mixed with different virgin or recycled plastics at 50% by weight fiber loading. The mixed materials were then compression molded into panels. Flexural and tensile properties and impact strength of the manufactured WPCs were determined according to the relevant standard specifications. Although composites containing PP (virgin and recycled) exhibited higher stiffness and strength than those made from HDPE (virgin and recycled), they had lower unnotched impact strengths. Mechanical properties of specimens containing recycled plastics (HDPE and PP) were statistically similar and comparable to those of composites made from virgin plastics. This was considered as a possibility to expand the use of recycled plastics in the manufacture of WPCs. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3641–3645, 2006 相似文献
38.
39.
S. Lucas E. Gonzlez M.P. Calvo C. Palencia E. Alonso M.J. Cocero 《The Journal of Supercritical Fluids》2007,40(3):462-469
Supercritical impregnation of Radiata pine with ethyl acetate and decanal using CO2 as carrier solvent has been studied at pilot plant scale. Radiata pine is one of the most common wood species that is originally from Australia and is widely grown in Spain and Portugal and ethyl acetate and decanal were selected as organic compounds.Some experiences were carried out to obtain the optimal operating conditions for the supercritical impregnation process. Experiments were conducted at pressures of 7–15 MPa, temperatures of 35–50 °C and solvent flow rate between 1.5 and 3.5 kg/h. The results of this study have indicated that the treatment gives much better preservative penetration and retention operating with low pressures (7.5 MPa), low temperatures (close to 35 °C) and moderate CO2 flow rate (3.5 kg/h) in the selected operating range. Moreover, a simple mathematical model of two adjustable parameters (external mass transfer coefficient and partition coefficient) has demonstrated to fit the experimental impregnation curves with reasonable accuracy (average absolute deviation, 3–10%). 相似文献
40.
一种新颖的室温固化双组分水性木器涂料与相应的单组分涂料相比,其显著特点涂膜有极好的附着力、更高的硬度、优异的耐水、耐烫、耐溶剂和抗粘连及耐污渍性等。其配漆后的适用期室温下可达30d以上,涂料的综合性能可与溶剂型漆相媲美。 相似文献