酸沥滤钠硅酸盐玻璃制造高硅氧玻璃纤维性能的研究

以纯碱和石英砂为主要原料制备钠硅酸盐原始玻璃纤维，经酸沥滤、水洗、烘干、烧结等工艺处理后，得到SiO2含量达96％以上的高硅氧玻璃纤维。本文研究了钠硅酸盐原始玻璃纤维的玻璃组分、不同浓度的酸沥滤玻璃纤维的离子交换反应进程，酸沥滤、水洗和烧结等工艺条件对纤维性能的影响。研究结果表明，原始玻璃组分中，随着钠含量的增加，原始玻璃纤维化学稳定性迅速降低，制造的高硅氧纤维强度下降，原始组分中引入少量氧化铝有利于提高高硅氧玻璃纤维的强度。提高酸溶液温度，能够加快酸沥滤反应速度，缩短反应时间。酸沥滤及水洗烘干后，高硅氧纤维呈封闭的多孔结构，在高温下开始收缩，高温收缩量较低，纤维的强度随着热处理温度的提高而提高，但1100℃高温强度低于无碱和硼硅酸盐玻璃制造的高硅氧玻璃纤维。     

酸沥滤对高硅氧玻璃纤维结构及性能的影响

通过扫描电子显微镜和红外光谱仪观察纤维前驱体酸沥滤前后的形貌和结构变化,通过ICP分析Na+的沥出过程,研究了盐酸浓度、温度以及沥滤时间对纤维前驱体Na+沥出率及力学性能的影响.结果 表明:高硅氧纤维前驱体在90℃的3 mol/L盐酸溶液中沥滤12 h后,纤维中的Na+沥出率达到85％以上;当盐酸浓度为5 mol/L时...     

酸沥滤对高硅氧玻璃纤维结构及性能的影响EI北大核心CSCD

通过扫描电子显微镜和红外光谱仪观察纤维前驱体酸沥滤前后的形貌和结构变化,通过ICP分析Na^(+)的沥出过程,研究了盐酸浓度、温度以及沥滤时间对纤维前驱体Na^(+)沥出率及力学性能的影响。结果表明:高硅氧纤维前驱体在90℃的3 mol/L盐酸溶液中沥滤12h后,纤维中的Na^(+)沥出率达到85%以上;当盐酸浓度为5mol/L时,沥滤后纤维的强度保留率最高。在酸沥滤过程中纤维中的Na^(+)与盐酸中的H^(+)置换,在热处理过程中羟基进一步聚合脱水补强玻璃网络体,实现纤维强度的提升。     

酸沥滤对高硅氧玻璃纤维结构及性能的影响EI北大核心CSCD

通过扫描电子显微镜和红外光谱仪观察纤维前驱体酸沥滤前后的形貌和结构变化,通过ICP分析Na^(+)的沥出过程,研究了盐酸浓度、温度以及沥滤时间对纤维前驱体Na^(+)沥出率及力学性能的影响。结果表明:高硅氧纤维前驱体在90℃的3 mol/L盐酸溶液中沥滤12h后,纤维中的Na^(+)沥出率达到85%以上;当盐酸浓度为5mol/L时,沥滤后纤维的强度保留率最高。在酸沥滤过程中纤维中的Na^(+)与盐酸中的H^(+)置换,在热处理过程中羟基进一步聚合脱水补强玻璃网络体,实现纤维强度的提升。     

玻璃成分与酸沥滤关系的探讨

从3种玻璃纤维成分入手,分别分析了3种玻璃酸沥滤过程中SiO_2质量分数的变化和玻璃成分的溶出,分析了该过程中的溶出机理。从微观形态的角度探讨了酸沥滤对高硅氧布力学性能的影响,指出高硅氧纤维性能与酸沥滤的时间、温度、酸度以及纤维本身的成分都有关系,在开拓高硅氧纤维应用领域的时候,应从用途出发筛选酸沥滤因素。     

酸沥滤和热处理对SiO2-Na2O系统高硅氧玻璃纤维结构的影响

高硅氧玻璃纤维应用广泛、性能优异.目前制备高硅氧特种玻璃纤维的主要方法是酸沥滤.酸沥滤法是将玻璃纤维原纱通过酸沥滤,热处理等工艺制备得到高硅氧玻璃纤维.采用Raman光谱研究SiO2-Na2O二元系玻纤在酸沥滤、热处理工艺制备高硅氧玻璃纤维过程中的纤维结构变化.结果表明:酸沥滤过程使硅氧四面体的弯曲振动峰和不对称伸缩振...     

高硅氧发光玻璃的制备及其荧光性能

石英玻璃具有低膨胀、耐热冲击、高机械强度和高化学隐定性等优点,是稀土和过渡金属发光离子掺杂的优选的基质材料。但发光离子在石英玻璃中容易自发形成团簇,产生浓度淬灭效应,介绍一种用二氧化硅质量分数超过95%的纳米微孔玻璃来抑制发光离子团簇的自发形成的新方法,以制备高发光强度的石英破璃和激光玻璃。该方法是将发光离子浸入微孔玻璃中并在适当气氛中烧结,目前已经制得多种颜色、量子效率接近于1的强发光玻璃,真空紫外光激发发光玻璃,高铒离子掺杂的高硅氧玻璃,还获得了新颖的低膨胀、耐高温的掺钕高硅氧激光玻璃和掺铋红外宽带发光玻璃用这种方法还容易进行多种发光活性离子掺杂,实现不同离子间的能量转换,提高发光强度和改变激发光的波长范围。这种新方法有望扩大石英发光玻璃的应用范围。     

红柱石对莫来石-高硅氧玻璃材料性能的影响

以莫来石M40(3~1 mm、≤1 mm和≤0.088 mm)和红柱石(1~0.5 mm、≤1 mm和≤0.074 mm)为原料,固定骨料和基质质量分数分别为70%和30%,调整红柱石的加入量(≤0.088 mm的加入量分别为0、5%、10%、15%、20%)和粒度(3种粒度分别添加10%),外加5%的硅溶胶结合剂,经混合、成型和烘干后,于1 200~1 600℃的空气气氛中保温3 h煅烧,测定烧后试样的线变化率、显气孔率、体积密度、耐压强度、荷重软化温度和抗热震性,并用SEM观察热震前后试样的显微结构。结果表明:(1)在相同煅烧温度下,随红柱石粉(≤0.088 mm)含量的增加,试样的线收缩率减小,显气孔率增大,体积密度下降或基本保持不变,耐压强度总体上逐渐增大;(2)在红柱石粉添加量相同的情况下,随煅烧温度的提高,试样线收缩率增大,显气孔率下降,体积密度增大,耐压强度升高;(3)加入不同粒度的红柱石均有利于提高材料的荷重软化温度,且采用1~0.5 mm的红柱石和提高烧成温度更加有效;加入不同粒度红柱石的试样,抗热震性均不是很好,其中以加入≤1 mm红柱石的试样抗热震性最好,加入1~0.5 mm的次之,加入≤0.074 mm的最差。     

莫来石－高硅氧玻璃相材料的制备研究

采用一种高岭石类粘土,制备了一种由莫来石和高硅氧玻璃构成的材料,并探讨了不同添加剂对该材料的烧结及其结构、性能的影响。由于高硅氧玻璃相在高温下具有高粘度,以及低温下具有较低的热膨胀系数,故对由该材料制成的耐火制品的高温性能和热震稳定性都是十分有利的。     

掺铝钕高硅氧玻璃的制备及光谱性能研究

采用分相酸溶工艺制备了Na2O-B2O3-SiO2体系纳米多孔玻璃,并以此为基质进行了钕铝掺杂的实验,制备了掺钕铝高硅氧玻璃,光谱分析表明,所制得的玻璃在1064 nm附近有明显的发射峰.研究了掺杂浓度、烧结气氛对玻璃光谱性能的影响,分析了铝离子在共掺杂玻璃中的作用.结果表明在浓度为0.2 mol/L的Nd(NO3)3溶液中制备的掺杂高硅氧玻璃发光强度最强,还原气氛下烧结的掺杂高硅氧玻璃光谱强度高于在空气中烧结得到的高硅氧玻璃,同时在还原条件下铝离子能够明显的提高玻璃的发光强度.     

Sorption properties of the composite fibers made of PAN and chitosan

A composite fiber of polyacrylonitrile (PAN) and chitosan was obtained by spinning the mixture of PAN/chitosan with a certain amount of diluted acetic acid as a plasticizer. Water plasticizes the PAN and acetic acid plasticizes the chitosan. The fiber showed a porous and fibrillar structure, which could be converted easily into pulplike short fiber by pulping. PAN/chitosan pulp showed a much higher amount of uptake for acid dye than that of either powdery chitosan or activated carbon. It is considered that this better sorption capacity of the composite fiber results from the relatively large surface area attributed to its pulplike shape. The adsorption behavior of the composite fiber was considerably affected by temperature and pH because the adsorption is exothermic and proceeds by an acid–base reaction. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2505–2511, 2002     

用矾土制备莫来石-高硅氧玻璃材料的研究

用Al2O3含量在57％～62％的矾土制备了一种由莫来石与高硅氧玻璃所构成的材料。在高温下，玻璃转变为高粘度的液相对高温性能有利；低温下，由于高硅氧玻璃的热膨胀系数低，莫来石形成交叉网络结构，有利于提高热震稳定性。这是一种有广泛前途的耐火原料，也为我国二级矾土的开发利用开辟了新途径。     

电镀污泥烧结砖的物理力学性能及浸出风险评估

探讨了在烧结制备红土砖和黏土砖的过程中掺入不超过10%(质量分数)的电镀污泥对其物理力学性能的影响,并评估了其重金属长期浸出风险。结果表明,掺入10%电镀污泥的烧结砖质量损失最大达到11.23%,线性收缩率最大达到-5.7%,吸水率最大达到11.47%,孔隙率最大达到22%,抗压强度最大达到15.66 MPa,皆满足国家相关标准要求;黏土砖的各项性能优于红土砖。浸出风险研究表明,总铜、总锌、总铬、总镍的最大浸出浓度分别为0.45、0.92、0.13和0.19 mg/L,远低于危险废物鉴定标准,表明掺入电镀污泥的烧结砖不是危险废物。     

Effects of glass fibers and polypropylene/glass fiber hybrid fibers on the kinetics and mechanical properties of epoxy composites

Curing reactions of diglycidyl ether of bisphenol F (DGEBP‐F) and pre‐catalyzed methyltetrahydrophthalic anhydride (MTHPA) with benzyl triethyl ammonium chloride (BTEAC) were studied and effects of glass fibers evaluated. The influence on the kinetics of glass fibers and a hybrid blend of maleated polypropylene + glass fibers is studied. Isothermal and dynamic kinetic parameters are determined by differential scanning calorimetry (DSC). Applicability of the autocatalytic model is investigated. The model serves well in the range of degrees of conversion between 25 and 80%. At high conversion rates the diffusion control becomes apparent. Glass fibers accelerate the curing, shortening the time needed to reach the maximum reaction rate; this is reflected in lower activation energies for curing in comparison to the neat resin. The effects observed can be explained by a reaction between the amine group present on the fiber surfaces and the epoxy glycidyl groups. The result of both isothermal and non‐isothermal curing of resin + glass fibers commingled with polypropylene are close to those for the neat resin. The reinforcement increases the elastic modulus 12 times, the tensile strength 2 times, and the impact strength 285 times. The glass fibers + commingled polypropylene reinforcement provides comparable mechanical properties as glass fibers alone when normalized with respected to the density fraction of the fibers.     

Rheological,mechanical, and adhesive properties of thermoplastic-LCP blends filled by glass fibers

Rheological, mechanical, and adhesive properties have been studied of two-phase polymer blends containing a liquid crystal copolyester of poly(ethylelene terephthalate) and p-hydroxybenzoic acid plus isotactic polypropylene (PP) with varying compositions and concentrations of glass fibers. Perfect fibrillation of the disperse LC-phase into the PP-matrix in capillary flow was observed at LCP concentrations >20 wt% and temperatures >488 K. This effect leads to a decrease of blend viscosity and a reinforcing of the extrudate's mechanical characteristics. At the same time, more essential reinforcement is achieved by the simultaneous addition of the reinforcing agents both of the LCP and glass fibers. Processing of PP is not impaired. It was found that the adhesive strength increases substantially when the amount of LCP in the blend exceeds a definite level, corresponding to a phase inversion. The results are explained by the formation near the interface of two adhesion layers: the first is composed of pure LCP having a higher surface tension, whereas the second layer represents the blend of various compositions. At small amounts of LCP, the adhesion failure proceeds in the interphase between the LCP and the blend. After the phase inversion, where adhesion strongly increases, the failure of adhesion joints proceeds near the interface between LCP and the glass.     

Preparation and properties of ferromagnetic glass-ceramics and glass fibers in alkali-free and high-iron glass system

We prepared ferromagnetic glass-ceramics in the system SiO₂-Al₂O₃-SrO-B₂O₃-Fe₂O₃ via four different methods, i.e., fiber-drawing, melt-quenching, natural-cooling, and annealing, without performing any nucleation and crystallization heat treatment. The influences of chemical compositions and fabrication methods on the spontaneous crystallization of magnetite in the as-prepared glass ceramics were investigated by X-ray diffraction, scanning and transmission electron microscopy. The X-ray diffraction patterns show that the nanometric magnetite crystals exist in a glass matrix. The spontaneous crystallization of magnetite can be enhanced with increasing alumina content. The size of crystallized magnetite is dependent on the chemical composition. The magnetic hysteresis circles of the glass-ceramic samples were analyzed using a vibrating sample magnetometer (VSM) in a 450 KA/m magnetic field. We find that both the saturation magnetization (M_S) and coercivity (H_jc) are changed with the variation of chemical compositions and fabrication methods. Calorimetric measurements were carried out using Orton Standard Dilatometers and we found that the softening point (T_S) and the coefficient of thermal expansion (CTE) of the annealed samples show non-monotonic dependence on the chemical composition.     

芳纶以及连续玄武岩纤维和玻璃纤维的耐酸性研究

测试和分析了芳纶、连续玄武岩纤维和玻璃纤维分别在65、80和95℃下浓度为2 mol/L的盐酸溶液中经不同时间的腐蚀后其力学性能以及质量的变化情况。结果表明,芳纶(芳酰胺纤维)的耐酸性能最优,其断裂强力和断裂伸长率的保持率最大;连续玄武岩纤维其次,玻璃纤维最差。因此芳纶比连续玄武岩纤维和玻璃纤维更适合用于酸性环境中,连续玄武岩纤维和玻璃纤维应尽量避免酸液对其的作用。