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二氧化钛对PP/SPTW复合材料性能的影响 总被引:1,自引:1,他引:0
目的研究不同质量分数的二氧化钛(TiO_2)对聚丙烯/六钛酸钾晶须复合材料力学性能的影响,并找出TiO_2的最佳质量分数。方法首先采用硅烷偶联剂KH550改性二氧化钛和六钛酸钾晶须(SPTW),然后将改性过的二氧化钛与改性过的六钛酸钾晶须、马来酸酐接枝聚丙烯(PP-g-MAH)、聚丙烯(PP)通过熔融共混法制得PP/PP-g-MAH/SPTW/TiO_2复合材料。结果比较了不同含量二氧化钛对聚丙烯/钛酸钾晶须复合材料性能的影响。研究表明,二氧化钛能够明显改善复合材料的力学性能,随着二氧化钛含量的递增,复合材料的力学性能总体呈先增加后降低的趋势。当二氧化钛质量分数为1%时,复合材料的弯曲强度、拉伸强度和冲击强度分别增大了35.2%,41.2%和33.7%。随着TiO_2质量分数的继续增加,复合材料的弯曲强度逐渐开始下降,拉伸强度和冲击强度在其质量分数超过2%时逐渐开始减小。结论当TiO_2质量分数约为2%时,复合材料的综合力学性能最佳。 相似文献
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不同偶联剂改性PTW对PP/GF复合材料性能的影响 总被引:7,自引:6,他引:1
目的研究六钛酸钾晶须表面改性对聚丙烯复合材料的力学性能影响,以探索最佳表面改性手段。方法分别采用硅烷偶联剂KH550、KH570、正十二烷基三甲氧基硅烷,钛酸酯偶联剂NDE311、改性六钛酸钾晶须(PTW),然后将改性过的六钛酸钾晶须、玻璃纤维、聚丙烯通过熔融共混制得聚PP/GF/PTW复合材料。结果比较六钛酸钾晶须经不同偶联剂改性前后对聚丙烯/玻璃纤维复合材料性能的影响,发现改性过的六钛酸钾晶须可改善复合材料的力学性能。比较不同偶联剂改性六钛酸钾晶须对聚丙烯/玻璃纤维复合材料性能的影响,发现经KH550偶联剂处理后,与未改性相比,复合材料的弯曲性能提高了58.63%,拉伸性能提高了16.07%,冲击性能提高了63.1%。结论六钛酸钾晶须经KH550偶联剂处理后,复合材料的综合性能最好。 相似文献
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ZnO纳米材料异质结是构筑高性能紫外光电探测器的有力候选之一。本工作中, 设计并制备了一种新型ZnO纳米棒/ZnCo2O4纳米片异质结, 研究了其电学性能及光电探测性能。使用油水界面自组装, 将ZnCo2O4纳米片在ITO玻璃上组装为均匀的薄膜; 通过调控ZnO种子层厚度, 在ZnCo2O4纳米片薄膜上水热生长了取向一致、密度适中的ZnO纳米棒阵列, 获得了高质量的ZnO纳米棒/ZnCo2O4纳米片异质结。该异质结具有优良的整流特性, 整流比达到673.7; 其工作在反偏状态时, 光暗电流比超过2个量级, 紫外-可见判别比为29.4, 在光电探测中有良好的波长选择特性。研究表明, 该异质结有潜力应用于构筑高性能紫外光电探测器。 相似文献
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近年来, 柔性电子器件由于在物联网、生物电子等领域的潜在应用引起了研究者的广泛关注。功能氧化物材料在柔性聚合物中的集成已被证明是实现高性能柔性电子器件的有效方式。由于功能氧化物薄膜通常需要高温制备, 直接在柔性聚合物基底上合成高质量的氧化物薄膜仍然是一个巨大的挑战。本研究提出了一种基于MoS2/SiO2范德华异质结转移打印大面积VO2薄膜的方法, 即利用MoS2和SiO2薄膜亲疏水性能的不同, 可以仅使用去离子水解离MoS2/SiO2范德华异质结界面, 成功将Si/SiO2/MoS2/SiO2/VO2 多层膜结构上的VO2薄膜转印到Si、SiO2/Si以及柔性基底上。X射线衍射(XRD)结果显示, 转印前后VO2薄膜的晶体结构没有差异, 变温Raman光谱和变温红外反射光谱证明了转印前后VO2薄膜良好的金属-绝缘体转变性能。本研究提供了一种有效的功能氧化物薄膜转印方法, 在不引入牺牲层和腐蚀性溶剂的条件下, 实现了VO2薄膜在任意基底上的低温集成, 为柔性可穿戴电子器件的研制提供了一种新思路。 相似文献
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氨气污染是空气污染的重要因素之一, 且氨气容易诱发急性水肿和呼吸衰竭等疾病, 严重危害人体健康。开发高性能氨气传感器已经成为氨气实时监测和安全预警的重要手段。本工作采用水热法制备了纳米花状、纳米球状和纳米片状三种不同形貌的二硫化钼, 以此构建了三种MoS2氨气传感器, 并利用自主搭建的气敏检测平台进行气敏性能研究。气敏实验结果表明: 在三种不同形貌的MoS2氨气传感器中, 纳米花状MoS2传感器对于氨气具有更好的响应性能, 对于10×10-6 NH3的响应值为7.41%, 而相同氨气浓度条件下的纳米片状和纳米球状MoS2传感器的响应值分别为2.01%和5.11%。此外, 纳米花状MoS2传感器还表现出优异的可重复性、稳定性和选择性。纳米花状MoS2传感器具有优越的响应性能, 主要因为其具有较大的比表面积, 可为NH3的吸附提供更多的活性位点。本研究为采用MoS2作为基底材料制备高性能的NH3传感器提供了新思路。 相似文献
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Deformation and fracture properties of damage tolerant in-situ titanium matrix composites 总被引:1,自引:0,他引:1
This paper discusses the tensile response and fracture toughness of in-situ titanium alloy metal matrices discontinuously-reinforced
with whiskers of titanium boride which were success-fully produced by ingot metallurgy techniques. Additions of elemental
boron resulted in a near uniform dispersion of the rod-like titanium boride (TiB) reinforcements in the alloy matrix. Such
composites have engendered considerable scientific and technological interest due to their attractive combinations of improved
mechanical properties and low manufacturing cost. The improved elastic moduli of the composites are explained using shear
lag and rule-of-mixtures theories. The increased strengths of the in-situ composites are rationalized by considering the combined
effects of deformation restrains imposed by the stiff whiskers and strengthening contributions arising from the substructure
that evolves from the presence of additional dislocations. 相似文献
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进行了含粘结剂和不含粘结剂的SiC纳米颗粒激光照射原位生成SiC晶须的比对试验,用X射线衍射仪(XRD)和扫描电子显微镜(SEM)分析了晶须的相组成和微观形貌,研究了粘结剂对生成晶须的影响。结果表明,在适当的激光参数下,不含粘结剂和含粘结剂的样品中均有晶须生成,不含粘结剂样品中晶须数量较少,而含粘结剂样品中晶须数量众多,且尺寸、形态各异。SiC纳米颗粒中掺入粘结剂可大幅度提高SiC晶须的生成数量,但并不影响晶须的纯度。 相似文献
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哑铃形碳化硅晶须的微观结构分析 总被引:7,自引:0,他引:7
利用透射电子显微镜观察和分析了仿生哑铃形碳化硅晶须的微观结构。这种碳化硅仿生晶须由成分和结构均不相同的两部分构成:中间是直杆状碳化硅晶须。在晶须上包裹着非晶态的念珠小球。由于成分组成的不同,念珠状小球具有均匀的和不均匀的两种微观结构;由于在其中存在大量的微孪晶、堆垛层错等缺陷,直杆状晶具有一维无序、竹节状等复杂的微观结构。在具有不同微观结构和形貌的直杆状晶须上,念珠状小球的开关和分布也有所不同。念球状小球中单质Si的含量是影响仿生晶颜色的主要因素,Si含量越高则仿生晶须的颜色越深。仿生晶须的生成过程是:先由气相反应生成直杆状碳化硅晶须,然后在直杆状碳化硅晶须上沉积生成非晶态念珠状小球。 相似文献
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《Materials Letters》2005,59(19-20):2593-2597
The SiC whiskers of good quality are expected to act as the reinforcing element in the ceramic coatings for C/C composites. Using CH3SiCl3(MTS) and H2 as the precursors, SiC whiskers were prepared on the surface of C/C composites by chemical vapor deposition (CVD) at normal atmosphere pressure. XRD, SEM and TEM analyses show that the whiskers are β-SiC structure and their diameters are several-hundred nanometers. With the descending MTS concentration in the depositing room, the purity of the as-prepared whiskers increases and the diameters of the whiskers decrease. The investigation of growth mechanism shows the CVD-SiC whiskers grown up by the vapor–solid (VS) growth process. 相似文献
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Microstructure of β-SiC whiskers with differ-ent cross-sections perpendicular to their growingdirection was studied in detail by transmission elec-tron microscopy (TEM).It was indicated that therewere three types of cross-sections:round,hexagonal and trigonal.The whiskers with roundand hexagonal cross-sections had a high density ofplanar faults lying on the (111) close packed planesperpendicular to the whisker axis.There existed afew stacking faults on the other {111} planes insome hexagonal whiskers.The whiskers withbicrystals were also found in hexagonal whiskers.The microstructure of trigonal SiC whiskers wasbasically perfect but there were a few intrinsic stack-ing faults on the (11) planes (mostly) and (111)planes.The characters of electron diffraction pat-terns of β-SiC whiskers with different cross-sec-tions were reasonably analyzed using a reciprocalspace model with continuous diffraction streaksalong the [111] reciprocal direction. 相似文献
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This paper discusses the tensile response and fracture toughness ofin-situ titanium alloy metal matrices discontinuously-reinforced withwhiskers of titanium boride which were successfully produced by ingotmetallurgy techniques. Additions of elemental boron resulted in a nearuniform dispersion of the rod-like titanium boride (TiB) reinforcements inthe alloy matrix. Such composites have engendered considerable scientificand technological interest due to their attractive combinations of improvedmechanical properties and low manufacturing cost. The improved elasticmoduli of the composites are explained using shear lag and rule-of-mixturestheories. The increased strengths of the in-situ composites are rationalizedby considering the combined effects of deformation restraints imposed by thestiff whiskers and strengthening contributions arising from the substructurethat evolves from the presence of additional dislocations. 相似文献