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利用木材介孔结构制备新型复合材料研究进展 总被引:9,自引:0,他引:9
综述了近年来关于木材多孔结构的新概念以及利用木材多孔结构制备新型复合材料和功能材料的新方法、新技术.重点介绍了陶瓷化木材、金属化木材的制备和应用以及以木材为多孔模板的新材料的合成。利用木材独特的多孔结构和介孔结构,设计、制备结构和功能独特的新材料是仿生材料科学和介孔材料科学一个非常值得关注的研究领域。 相似文献
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陶瓷复合木材的渗透过程研究 总被引:2,自引:0,他引:2
本文论述了可作为阻燃木材使用的陶瓷复合木材的各种渗透处理方法及不同处理过程对陶瓷复合木材内部处理药液浓度分布的影响。发现采用化学和物理相结合的渗透方法,可以使处理药液有效地渗入材料,并得到较理想的浓度分布。 相似文献
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陶瓷化木材的复合机理 总被引:59,自引:0,他引:59
将主要组份为正硅酸乙酯(TEOS)的陶瓷前驱体溶液注入木材,经水解、缩合反庆、在木材细胞壁内形成二氧化硅与纤维素等有机组份的分子或纳米级复合结构。 相似文献
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木材作为一种天然可再生资源被广泛应用于各个领域.近年来,随着我国对木材需求的日益增长和天然林资源的匮乏,速生木材作为硬质木材的替代品越来越受到人们的关注.但速生木材存在密度低、材质疏松、力学性能欠佳等不足,难以用于制造高附加值产品,因此需要对其进行改性增强处理.速生木材具有大量的孔隙和活性官能团,通过浸渍改性不仅可提高其密度和力学强度,还能赋予速生木材新的功能,进而提升其使用价值.传统的浸渍改性按照浸渍液的不同主要分为有机和无机两种方式,但均存在一些不足.有机改性液浸渍中所使用的有机树脂虽能与木材的活性官能团发生交联而形成紧密的结构,但是大多有机树脂含有游离甲醛等易挥发的有毒物质,会对环境和人体健康造成危害.而无机改性剂虽无毒环保,但大多难以在木材中形成稳定的结构,易发生流失与吸湿等现象,影响使用功能.有机-无机复合改性是一种新型的材料复合技术,它能将有机材料与无机材料的优点结合起来,在减少有机树脂用量的同时充分利用其包覆作用(或键结合)来固定无机改性剂以减少流失,并且有机树脂能与木材形成稳定的键结合.因此,在有机-无机材料的协同作用下,改性木材的性能得以大幅度提升,实用价值和应用领域得到进一步扩展.本文以有机-无机复合改性速生木材的研究现状为主题,以硅系、硼系、铜、钙及蒙脱土等无机组分为主线,对其研究进展进行详细描述,并对改性机理进行归纳总结.同时,从基础理论、制备工艺、基本性能以及经济成本等方面提出了有机-无机复合改性木材的发展趋势,旨在推动有机-无机复合改性方法能在速生木材的改性中得到更广泛的应用. 相似文献
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采用固体废弃物甘蔗渣为原料,与环氧树脂混合后真空烧结制备碳木材陶瓷。利用TG-DSC分析了木材陶瓷的热分解行为。利用XRD、SEM表征了木材陶瓷的相组成和微观结构,研究了碳化温度对木材陶瓷的残炭率、体积收缩率、平面尺寸收缩率、厚度收缩率和体积电阻率的影响。结果表明:甘蔗渣制备的木材陶瓷是一种多孔碳材料,随着碳化温度升高,石墨化程度提高;烧结温度每升高100℃,残炭率降低约1%~2%,体积收缩率升高0.5%~1%。平面尺寸和厚度收缩率与烧结温度正相关。体积电阻率随温度升高而降低。 相似文献
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木材的非传统应用--热塑性木材、木材-塑料与木材陶瓷 总被引:2,自引:0,他引:2
木材经过化学改性可制备成易于加工且可生物降解的热塑性木材;也可与树脂或塑料进行复合得到木材-塑料(木塑复合材料);或者将其浸渍入树脂再进行炭化得到木材陶瓷.热塑性木材、木材-塑料与木材陶瓷具有良好的环境协调性和功能性,打破木材只能作为块状材料的传统使用,开辟了木材应用的新途径. 相似文献
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AbstractPorous ceramics with unidirectionally oriented pores have been prepared by various methods such as anodic oxidation, templating using wood, unidirectional solidification, extrusion, etc. The templating method directly replicates the porous microstructure of wood to prepare porous ceramics, whereas the extrusion method mimics the microstructures of tracheids and xylems in trees. These two methods are therefore the main focus of this review as they provide good examples of the preparation of functional porous ceramics with properties replicating nature. The well-oriented cylindrical through-hole pores prepared by the extrusion method using fibers as the pore formers provide excellent permeability together with high mechanical strength. Examples of applications of these porous ceramics are given, including their excellent capillary lift of over 1 m height which could be used to counteract urban heat island phenomena, and other interesting properties arising from anisotropic unidirectional porous structures. 相似文献
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Kiyoshi Okada Toshihiro Isobe Ken-ichi Katsumata Yoshikazu Kameshima Akira Nakajima Kenneth J D MacKenzie 《Science and Technology of Advanced Materials》2011,12(6)
Porous ceramics with unidirectionally oriented pores have been prepared by various methods such as anodic oxidation, templating using wood, unidirectional solidification, extrusion, etc. The templating method directly replicates the porous microstructure of wood to prepare porous ceramics, whereas the extrusion method mimics the microstructures of tracheids and xylems in trees. These two methods are therefore the main focus of this review as they provide good examples of the preparation of functional porous ceramics with properties replicating nature. The well-oriented cylindrical through-hole pores prepared by the extrusion method using fibers as the pore formers provide excellent permeability together with high mechanical strength. Examples of applications of these porous ceramics are given, including their excellent capillary lift of over 1 m height which could be used to counteract urban heat island phenomena, and other interesting properties arising from anisotropic unidirectional porous structures. 相似文献
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Min Luo Jiqiang Gao Xiao Zhang Guangya Hou Jianfeng Yang Da Ouyang Hongjie Wang Zhihao Jin 《Journal of Materials Science》2007,42(11):3761-3766
Porous titanium nitride ceramics with a biomorphic microstructure were manufactured at 1400 °C by carbothermal reduction and
nitridation of charcoal/titania composites under high concentration nitrogen atmospheres. These composites were prepared from
beech-derived charcoal impregnated with titania sol by vacuum/pressure infiltration process. The formation mechanism of TiN
was analyzed. The results show that the nitridation is based on gas–solid reaction among TiO (s), N2 (g), C (s) or CO (g). Under higher nitrogen pressure, the nitridation reaction was complete and porous TiN/C ceramics obtained.
The phase composition and microstructure of as-obtained porous TiN/C ceramics were characterized by X-ray diffraction and
scanning electron microscopy. Experimental results show that the resultant porous TiN/C ceramic had the same external and
internal forms of the original wood that consists of cubic phase TiN. 相似文献
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To make use of the porous nature of the SHS reaction products a novel investigation was made to manufacture the highly porous ceramics with SHS method by adding certain amounts of volatile agents to the green compacts. The interconnected open porosity of the obtained highly porous ceramics can be as high as 83% and the interconnected network open pore microstructure was developed in the obtained highly porous ceramics. Large amounts of micropores were found present in the obtained highly porous ceramics, which is a special and important advantage of manufacturing porous ceramics with SHS method. Also this particular combustion process was studied in detail and it was found that the propagation rates are increased considerably due to the unique green compact structure left by the volatile agents. 相似文献
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回顾了目前Si-Al-Zr-O系超微细晶复相陶瓷的主要研究方法并分析了这些方法的特点.针对应用超微细粉致密化制备Si-Al-Zr-O系陶瓷材料存在的烧结温度高(一般高于1500℃),致密化难,增韧相种类有限且成本高等问题,提出了一种新的制备方法——非晶原位受控晶化法,在较低温度1100~1200℃下制得均匀、致密、高可靠性的Si-Al-Zr-O系超微细晶复相陶瓷.该方法能有效避免高温烧结以及烧结过程中纳米粉末的团聚和晶粒异常长大,实现显微结构的有效控制,是一种具有发展前景的制备技术. 相似文献
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酚醛树脂/椴木木粉复合材料经高温真空碳化制成了木材陶瓷。利用XRD、SEM和FTIR技术对碳化温度和酚醛树脂/木粉质量比对木材陶瓷物相、微观结构和物理化学结构变化的影响进行了表征和研究。结果表明,木材陶瓷具有拓扑均匀的连通孔的三维网络结构,是含有C C、C—O—C和C—H等基团的类石墨结构的碳/碳复合材料;随碳化温度的升高,(002)峰强度增大,晶面间距d(002)降低,碳化木粉收缩,其间隙增大;酚醛树脂/木粉质量比增大,浸渍树脂的木粉成形能力改善,所得木材陶瓷结构更均匀,但其对木材陶瓷的XRD衍射花样影响不大。 相似文献
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以异丁烯和马来酸酐共聚物(PIBM)为分散剂和凝胶剂, 同时添加两种表面活性剂, 通过机械发泡和注凝成型工艺制备高气孔率Al2O3泡沫陶瓷, 并研究了DE211环氧树脂对Al2O3泡沫陶瓷结构和性能的影响。结果表明, 该工艺能够制备气孔率达92.4%的Al2O3泡沫陶瓷。随着DE211环氧树脂的加入, 泡沫陶瓷的气孔率略有降低, 抗压强度由0.5 MPa提高到3 MPa, 平均气孔尺寸由582 μm下降到331 μm, 孔壁塌陷少。这归因于DE211环氧树脂的环氧基能够与PIBM的酸酐发生反应, 加快凝胶固化速度, 从而有利于稳定泡沫结构。 相似文献
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采用无水乙醇基浆料结合喷雾造粒工艺制备YAG透明陶瓷粉体, 通过扫描电子显微镜、压汞仪、能谱仪及紫外–可见–红外透过光谱系统研究了不同PVB粘结剂添加量下YAG造粒颗粒的形貌、尺寸、成型性能及其破碎行为, 对成型素坯的孔分布及烧制透明陶瓷的显微结构及光学性能进行了详细表征。在优化PVB添加量为1.0wt%时, 造粒粉体为实心单分散颗粒, 球形度高、化学均匀性好, 其平均粒径约为40 μm, 成型性能优异; 在75 MPa压力下, 造粒颗粒完全破碎形成密实均一的坯体结构。烧结后的YAG透明陶瓷显微结构均一, 无气孔及其他缺陷, 光学质量优异。 相似文献