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不同树种木粉/PVC复合材料天然耐腐性对比研究 总被引：1，自引：0，他引：1
选用5种不同树种木粉与PVC制备木塑复合材料,通过人工模拟加速试验对比研究不同组别复合材料对采绒革盖菌和绵腐卧孔菌的天然耐腐性差异,采用扫描电镜(SEM)和水分吸附测试深入分析腐朽菌对复合材料微观形貌及界面结合的影响,结果表明:不同组别复合材料对彩绒革盖菌耐腐性排序为:杉木/PVC马尾松/PVC白千层/PVC枫香/PVC尾巨桉/PVC复合材料;对绵腐卧孔菌耐腐性排序为:杉木/PVC尾巨桉/PVC、白千层/PVC、马尾松/PVC枫香/PVC复合材料。腐朽菌菌丝可通过木粉和PVC树脂界面结合空隙处进入试样内部进行侵蚀,从而降低复合材料间的界面结合,使其水分吸附率明显增加。 相似文献
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指出了木塑复合材料具有耐腐蚀性能好、耐低温、机械性能好、无有毒气体释放等优点,其优异的物理化学性能使其成为一代新型的环保复合材料,在生活和生产中得到广泛的应用,对于木材替代材料的发展具有重要意义。以聚丙烯为基体材料,以木质纤维作为填料,制备了聚丙烯木塑材料,采用热压成型原理制备木塑复合材料板材,并进行了力学性能、热稳定性、吸水性等性能测试。研究了木粉细度、木粉含量、聚乙烯增韧聚丙烯的配比、采用不同偶联剂LD-125、KH-550、KH-570进行改性等因素对聚丙烯木塑复合材料性能的影响。运用单因子试验和正交试验方案,探讨了聚丙烯木塑复合材料力学性能的影响因素,并优化了工艺配方的方案,对聚丙烯木塑复合材料的研究与开发具有重要的意义。 相似文献
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木塑复合材料的界面相容性是决定其性能的关键因素,通过添加偶联剂的方法能够改善其界面相容性,从而提高其性能。通过测定毛白杨木粉/聚丙烯复合材料的物理力学性能来研究木粉含量和偶联剂添加量对木塑复合材料物理力学性能的影响,为进一步研究木塑复合材料的界面相容性提供理论依据。研究结果表明:随着木粉含量的增加,复合材料的物理力学性能下降,并且在高木粉含量阶段影响显著;高木粉含量复合材料的性能较差,添加MAPP能显著改善其物理力学性能。 相似文献
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用4种热处理方法处理腺瘤豆心材,可有效去除异味,替代珍贵绿柄桑木材使用.处理后的木材经白腐菌侵染 12星期,平均质量损失率与未经处理的试材相比变化不大,天然耐久性等级保持不变,而且其中2种处理方法还能够明显提高木材的耐腐性能,木材的天然耐久性等级因此也由Ⅱ类提高到Ⅰ类. 相似文献
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木结构覆板用胶合板的防腐处理工艺及性能评价 总被引：1，自引：0，他引：1
《木材工业》2020,(3)
采用铜唑防腐剂,测试处理后胶合板的耐腐性能和力学性能。通过评价处理试板的吸液量和透入度,结合考虑生产效率,确定的优化真空处理工艺为:真空-0.04 MPa处理10 min,常压渗透保持10 min。在此条件下处理的试板受褐腐菌和白腐茵侵染后的质量损失率均小于5%,达强耐腐等级;弹性模量和静曲强度满足GB/T 22349—2008《木结构覆板用胶合板》的要求。 相似文献
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木粉加入量对木／塑复合材料性能影响的研究 总被引：18，自引：0，他引：18
研究了聚丙烯与木粉以不同比率复合而成的材料的物理力学性能和复合形态特征。结果表明：不同混合比率的聚丙烯与木粉进行复合后所得的复合材料，除冲击强度有所降低外，其它力学性能均比纯聚丙烯的有较大幅度的提高。木粉表面的酯化处理可以改善木塑界面之间的相容性和复合材料的均匀性。在木塑复合过程中木塑之间发生镶嵌现象使木塑之间产生物理结合。 相似文献
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QIN Te-fu HUANG Luo-hua LI Gai-yun 《林业研究》2005,16(3):241-244
对以铝酸酯为偶联剂对木粉进行表面改性处理后制备的木粉/聚丙烯复合材料的力学性能和形态学特征进行了研究。结果表明:铝酸酯偶联剂可以增加木塑复合材料的抗冲击强度,但会对复合材料的抗拉强度和抗弯强度造成负面的影响。对木塑复合材料的动态力学性能和微分扫描热量分析研究表明,以铝酸酯作为偶联剂,对木塑复合材料的储存模量和损失模量有少许增加,同时可降低材料的熔点和熔解热。利用扫描电镜观察木塑复合材料的木材与塑料界面发现,经铝酸酯处理过的木材与聚丙烯复合界面之间具有更好的相容性。这些研究结果表明,在木塑复合材料制造过程中利用廉价的铝酸酯作为木材化学改性剂,对改善复合材料的性质同样起作良好的作用。图6 表2 参16。 相似文献
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Khandkar- Siddikur Rahman Md Nazrul Islam Sourav Bagchi Ratul Nabila Hasan Dana Saleh Md. Musa Md. Obaidullah Hannan 《Journal of Wood Science》2018,64(3):279-286
This paper presents the effects of particle size and mixing ratio on the properties including physical, mechanical, and decay resistance of wood plastic composites (WPCs). In addition, it also presents the effects of immersion temperatures on water absorption (WA) and thickness swelling (TS) of the WPCs. WPCs with a thickness of 6 mm were fabricated from Albizia richardiana King & Prain wood particles and recycled polyethylene terephthalate (PET) by the flat-press method. To prepare the WPCs, two different wood particle sizes (0.5–1.0 and 1.01–2.0 mm) were used along with four different mixing ratios (w/w). Subsequently, the physical properties include density, moisture content, WA, and TS, and mechanical properties include modulus of elasticity (MOE) and modulus of rupture (MOR) of the produced WPCs was evaluated. Furthermore, decay resistance was evaluated by the weight loss percentage method. Moreover, the effects of immersion temperatures on WA and TS of WPCs after 24 h of immersion in water at three different temperatures, i.e., 25, 50, and 75 °C were investigated. Results showed that the wood particle size had impact on WPC’s density (only 6% decreased with the increase of particle size); however, the density decreased by 29% when the wood particle content increased from 40 to 70%. The WA and TS gradually increased with the increase of particle content and decrease of particle size. In addition, WA and TS increased proportionately with increasing immersion temperature from 25 to 75 °C. Furthermore, the highest MOE (2570 N/mm2) was found for the WPCs fabricated from large wood particles having the ration of 50:50 (wood particle:PET). For decay resistance, WPCs consisted of larger particles and higher PET content showed greater resistance against decay. Therefore, it is comprehensible that fabrication of the WPCs from 50% large particles and 50% PET is technically feasible and further improvement of WPC performance like enhancement of MOE and reduction of density using coupling agent and agricultural waste fibers, respectively, in the WPC formulation is recommended. 相似文献
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To verify master curves obtained based on time–temperature superposition principle for wood–plastic composites (WPCs), a 220-day long-term creep test was conducted under an unconditioned environment. In this study, WPCs were made by extrusion with various formulations; using mountain pine beetle-attacked lodgepole pine flour and high-density polyethylene as raw materials, as well as maleated polypropylene as coupling agent. The results showed that the effect of naturally elevated temperature during the summer months caused additional increases in creep strain. The information obtained from the conventional creep study method may be insufficient to reflect the practical application. Comparisons between long-term data and the master curves showed that the master curves tended to overestimate the real creep strain of large specimens and that the deviation increased with time. The prediction of the master curve agreed more reasonably with the long-term data for coupled WPC products, whereas the master curves showed considerable overestimation for the uncoupled ones. In general, the master curves cannot precisely predict the long-term creep strain, but merely provide conservative estimations. 相似文献
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We evaluated fungal decay and mold resistance, leaching, and water absorption of nano-compounds and Paraloid B72® (PB72) in treated wood specimens to develop new methods of consolidation by combining nano-particles and consolidants. Scots pine wood specimens were treated with dispersions of nano-CuO, nano-ZnO, nano-B2O3, nano-TiO2, and nano-CeO2. PB72 treatments of nano-particle-treated wood specimens were then carried out by either vacuum or immersion for 24 h. Previously, decayed wood specimens were also consolidated with the nano-compounds and PB72. PB72 treatments reduced element release from treated wood specimens. Nearly all nano-compounds + PB72 treatments increased the biological performance of treated wood specimens against decay fungi tested. PB72-only treated wood specimens had the highest weight losses in decay tests. No improvements were obtained in mold resistance tests when the nano-compounds and PB72 were combined. In nano-compound-only treatments, unleached specimens showed slightly lower water absorption values compared to untreated control specimens. Incorporation of PB72 into nano-compound-treated wood specimens resulted in considerably lower water absorption and volumetric swell. In previously decayed specimens treated with the nano-compounds and PB72 solution, water absorption after 2-h immersion declined compared to control specimens. 相似文献
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采用5种木材腐朽菌,分别对30株天然林白桦木材进行木材腐朽处理,检测并比较腐朽木材和新鲜木材中未质素、纤维素等主耍化学成分的变化。结果表明,木蹄层孔菌腐朽后的白桦木材其重量、木质素和纤维素损失率最高,桦剥管菌次之,白囊耙齿菌最低;木蹄层孔菌腐朽后的白桦木材纤维素含量略高于新鲜白桦木材,其他4种茵腐朽后的白桦木材纤维素含量都低于新鲜白桦木材,其中桦剥管菌和彩绒革盖菌腐朽后的白桦木材纤维素含量较低。木蹄层孔菌腐朽后的白桦木材1％NaOH抽出物含量最低,苯醇抽出物含量中等,纤维素含量最高,木质素含量较低,相比之下它腐朽白桦木材的能力较强,适用于以白桦木材为原料的生物辅助造纸。 相似文献
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Benny Green P. David Jones Darrel D. Nicholas Laurence R. Schimleck Rubin Shmulsky 《Wood Science and Technology》2011,45(3):583-595
The use of calibrated near infrared (NIR) spectroscopy for measuring and predicting the advancement of wood decay in Pinus spp. sapwood wafers that were subjected to Gloeophyllum trabeum for periods ranging from 1 to 10 days was investigated. NIR spectra were obtained from the center of the cross-sectional
face of each sample before and after decay tests. Mass loss and compression tests were also used to measure the progression
of decay. Calibrations were created from NIR spectra, mass loss, and compression strength data using untreated and mathematically
treated (multiplicative scatter correction and first and second derivative) spectra. Strong relationships were derived from
the calibrations with the strongest R
2 values being 0.98 (mass loss) and 0.97 (compression strength). Calibrations for mass loss showed the strongest statistics
for predicting wood decay of a separate test set (0.85 raw, second derivative to 0.76 multiplicative scatter correction (MSC),
while predictions for compression strength of the decayed samples resulted in R
2 of 0.69 (raw) to 0.54 (MSC). Calibrations created from the amount of time the samples were decayed showed strong statistics,
indicating that NIR spectroscopy can predict the early stages of wood decay. 相似文献
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木塑复合材料耐候性能研究进展 总被引：1，自引：0，他引：1
木塑复合材料(WPC)的耐候性能决定了材料的户外使用寿命。文中介绍了国内外在WPC耐热氧老化、耐光氧老化、耐真菌腐朽及耐潮湿与冻融性能方面的研究进展。现有研究表明, 热氧老化与光氧老化均使得WPC发生褪色现象, 力学性能下降, 添加抗氧化剂与光稳定剂可分别改善二者对WPC的破坏作用。WPC中木粉含量较高时更易发生真菌腐朽现象, 添加化学防腐剂或其他助剂、木粉改性及涂饰可有效抑制真菌腐朽。WPC的吸水性是其热氧老化、光氧老化、真菌腐朽及冻融循环过程的催化剂。文中还总结了目前WPC耐候性能研究存在的主要问题, 并对其未来趋势进行了展望。 相似文献
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《林业研究》2020,31(5):2023-2029
The experiment was conducted to improve the decay resistance of wood by increasing the wood preservatives uptake and penetration depth by bioincising with Coriolus versicolor. The mechanical properties of bioincised Populus davidiana sapwood were measured. The changes of wood components(lignin, cellulose and hemicellulose) were analyzed by FTIR. The staining treatment using potassium permanganate was to measure the preservatives uptake and penetration depth in wood specimens. The decay resistance of bioincised specimens impregnated with IPBC and CA was assessed against C.versicolor and Gloeophyllum trabeum using bioincised P.davidiana sapwood and untreated controls. The results showed that the mechanical properties of the bioincised specimens were changed with the incubation time and mass loss. The mechanical strength was decreased after 17 days compared to that of the specimens bioincised 13 days.The bioincised specimens demonstrated the deeper penetration depth than the un-bioincised specimens. It was significant correlation(P 0.01) between penetrationdepth and incubation time. The average value of the penetration depth of the bioincised specimens was deeper than the control groups by 158.7%. By FTIR analysis, the biodegradation ability of C. versicolor to decay cellulose and hemicellulose was weaker than that of lignin. The bioincising treatment significantly increased the wood uptake of IPBC and CA, and reached the maximum uptake value at 17 and 13 days, respectively. Summarily, the bioincising pretreatment can obviously improve the wood decay resistance against C. versicolor and G. trabeum following by introducing the IPBC and CA. 相似文献