热塑性树脂基纳米复合材料研究与应用

综述了热塑性树脂基纳米复合材料的研究与应用现状,主要介绍了以无机纳米颗粒、无机纳米晶须和纳米纤维素为填料的热塑性树脂基复合材料,并提出该领域研究中存在的问题,以期开发出性能满足要求的新型纳米复合材料。     

基于IF-MoS_2的复合材料制备及摩擦学性能研究

通过氧化还原反应与管式炉的真空加热,合成了无机类富勒烯结构二硫化钼纳米颗粒,并利用扫描电子显微镜、透射电子显微镜等手段对所合成的二硫化钼纳米颗粒进行了表征。采用粉末冶金技术,制备了含无机类富勒烯二硫化钼的自润滑材料,并利用UMT摩擦磨损试验机,研究了所制备的复合材料的摩擦磨损性能。研究结果表明,加入适量的二硫化钼纳米颗粒之后,复合材料的摩擦系数明显降低,抗磨损性能提高。     

不同无机粉体在PE木塑复合材料中的应用研究

通过在聚乙烯(PE)木塑复合材料中分别添加碳酸钙、滑石粉和硅灰石3种无机粉体材料,并采用扫描电子显微镜、万能力学性能实验机和热力学分析仪等对无机粉体的颗粒大小、微观形貌以及复合材料的力学性能等进行了测试。结果表明,硅灰石制备的PE木塑复合材料的弯曲性能最佳,滑石粉制备的PE木塑复合材料冲击性能较好;对于3种无机粉体而言,随着无机粉体添加量逐渐增加至15份(质量份,下同),PE木塑复合材料的力学性能逐渐提升,当无机粉体添加量增加至20份时,PE木塑复合材料的力学性能出现下降,密度和硬度逐渐增大,24 h吸水率和线性热膨胀系数逐渐降低。     

聚酯/SiO_2复合材料及其结晶性能研究

采用原位聚合技术,制备了添加微米、纳米二氧化硅(SiO2)的对苯二甲酸乙二醇酯(PET)复合材料。重点分析了微米、纳米SiO2无机颗粒在PET基体中的分散行为,并探究PET/SiO2复合材料的结晶行为与光学性能。结果表明:原位聚合使得微米、纳米SiO2颗粒以较好的单分散形态均匀分布在聚合物基体中;微米、纳米SiO2颗粒复配虽能促进PET的结晶,但相互之间不能产生协同作用;微米SiO2颗粒会严重影响PET复合材料的光学性能,而一定含量的纳米SiO2颗粒则会显著提高PET复合材料的光学性能。     

生物活性无机颗粒增强聚乳酸材料的制备方法

无机颗粒增强聚乳酸复合材料能有效的改善聚乳酸的力学性能，并赋予其生物活性。本文系统介绍了各种无机颗粒增强聚乳酸复合材料的制备方法，并对其优劣性进行了初步探讨。     

不同无机纳米颗粒增强硬质聚氨酯的性能对比

采用原位聚合的方法制备了不同无机纳米颗粒(二氧化硅、二氧化钛、埃洛石纳米管、蒙脱土)增强聚氨酯复合材料,研究了不同无机纳米颗粒增强聚氨酯材料对力学性能和防水性能的影响以及纳米颗粒在基体中的分布情况。结果表明,四种无机纳米颗粒在不同程度上提升了硬质聚氨酯的力学性能,其中含有1%二氧化硅(SiO₂)和1%埃洛石纳米管(HNT)的聚氨酯基复合材料提升效果比较明显,相比于硬质聚氨酯,它们的拉伸强度分别提高了约14%和10%,断裂伸长率分别提高了约32.2%和29.7%;但是疏水性方面的提升效果并不显著。     

无机纳米材料/热塑性聚氨酯复合材料的研究进展

无机纳米材料具有高熔点、高耐氧化等优异性能,在热塑性聚氨酯(TPU)复合材料中具有广阔的应用前景。简要综述了氮化硼(BN)、碳纳米管(CNTS)等不同无机纳米材料的基本性质和优异性能,重点介绍了无机纳米材料/TPU复合材料的制备方法、性能的研究进展,提出了制备无机纳米材料/TPU复合材料存在的问题,并对未来新型纳米复合材料的制备进行了展望。     

环氧树脂复合材料的摩擦学性能研究

综述了环氧树脂复合材料摩擦学性能研究的前沿进展,从无机润滑填料、纳米填料、纤维、有机填料的单一填充以及无机/无机、有机/无机、纤维/填料复合填充等方面阐述了环氧树脂复合材料中填充不同填料改性对其摩擦磨损性能的影响。复合填充多种填料可提高环氧树脂复合材料的耐磨损性能,降低其摩擦系数,使环氧树脂复合材料具有更优异的摩擦学性能。     

无机复合材料性能

正无机复合材料(玻璃钢)范围很广,主要指用纤维(主要是玻璃纤维)增强氯氧镁及硅酸钙的无机材料。除此,还有纤维增强水泥、纤维增强陶瓷等无机复合材料。要全面测试无机复合材料性能,除如固化度(树脂不溶性含量)之类性能外,与有机(聚合物)复合材料是差不多的。一般情况下,无机复合材料的性能主要指密度、干态弯曲(常称抗折或抗弯)强度、湿     

有机-无机复合材料中无机相分散度三维荧光分析

有机-无机复合材料因其优异的性能广泛应用于多个行业及领域,无机相分散度是决定复合材料质量、保证产品性能发挥的重要因素。因此,对复合材料中无机相分散度的有效评价是构筑高品质复合材料的关键步骤。本文介绍了有机-无机复合材料中无机相分散度的传统表征方法及亟待解决的问题。针对这些问题,综述了三维荧光成像法对有机-无机复合材料中无机相分散度的可视化评价研究进展：通过前染修饰、后染定位两种染色技术实现对无机相的染色识别;基于三维成像技术对复合材料中无机相进行定位及微观形貌分析;对无机相在介观尺度、三维空间的分散度进行定性及定量分析。该方法不仅适用于对复合材料制备工艺的筛选,也可用于对成品材料的现场无损分析。最后总结并展望了复合材料结构可视化的未来研究方向。     

Comparison of the Mechanical and Thermo-Mechanical Properties of Unfilled and SiC Filled Short Glass Polyester Composites

This paper presents a comparison between particulate filled (SiC particles) and unfilled glass polyester composites on the basis of their mechanical and thermo-mechanical properties. The results show that particulate filled composites have a decreasing trend in mechanical properties when compared to the unfilled glass polyester composites. In particulate filled composites, the tensile and flexural strength of the composites decrease with the addition of 10 wt.-% SiC particles but increase with 20 wt.-% SiC particles. In the case of the unfilled glass polyester composite, the tensile and flexural strength of the composites increase with an increase in the fiber loading. However, higher values of tensile strength and flexural strength of particulate filled glass polyester were found than that of the unfilled glass polyester composite. In the case of thermo-mechanical and thermal properties, the particulate filled composites show better dynamical and thermal properties when compared to the unfilled glass polyester composites. The mechanical and thermal properties (i.e. thermal conductivity) are also calculated using FE modeling (ANSYS software) and the results from this simulation shows good agreement with the experimental results.     

Interfacial shear strength of reduced graphene oxide polymer composites

Interfacial shear strength (IFSS) between particle and matrix in particulate polymer composites is a critical property in determining the mechanical behaviors since it is directly related to not only their Young’s modulus or specific strength, but also energy absorbing capability. However, the conventional techniques often present a technical challenge to accurately measure the IFSS between fillers and matrix in the composites. This is more apparent in graphene particulate composites due to their nano-scale dimensions as well as the platelet-shaped geometry. Here, the focus of this study is to use a semi-empirical approach to determine the IFSS of graphene particulate composites by combining experiments with finite element (FE) modeling. The materials of interest are reduced graphene oxide (RGO) and polycarbonate (PC). The tensile testing was performed to characterize the mechanical properties, while simultaneously monitoring the acoustic emission events in order to measure the global debonding stress (GDS) in the composites. By coupling thermal stress analysis and deformation analysis with the GDS as input to a FE model, the IFSS of the RGO particulate PC composites was successfully estimated by about 136 MPa, avoiding unnecessary assumptions and uncertainties which are seem to be inevitable with the conventional techniques for the IFSS measurement.     

Thermomechanical properties of poly(lactic acid) films reinforced with hydroxyapatite and regenerated cellulose microfibers

Novel composite films constituted of poly(lactic acid) (PLA), hydroxyapatite (HAp), and two types of regenerated cellulose fillers—particulate and fibrous type—were produced by melt extrusion in a twin‐screw micro‐compounder. The effect of the film composition on the tensile and dynamic mechanical behavior and the HAp dispersion in the PLA matrix were investigated thoroughly. Appearance of crazed regions and prevention of HAp aggregation in the PLA matrix were elucidated in the composites with up to 15 wt % particulate cellulose content, which was the main reason for only slight reduction in the tensile properties, and consequently trivial degradation of their pre‐failure energy absorption as compared to neat PLA films. Superior dynamical energy storage capacities were obtained for the particulate cellulose modified composites, while their fibrous counterparts had not as good properties. Additionally, the anisotropic mechanical behavior obtained for the extruded composites should be favorable for use as biomaterials aimed at bone tissue engineering applications. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40911.     

Mechanical properties of particulate‐filler/woven‐glass‐fabric‐filled vinyl ester composites

Studies of the effect of particulate fillers on specific mechanical properties of vinyl ester epoxy (VE) reinforced with woven glass fiber composites were carried out with different filler types and particulate filler contents (1%, 3%, and 5% by weight). Two types of particulate filler were used, i.e., calcium carbonate (CC) and phenolic hollow microspheres (PHMS). The composites were prepared by using a hand lay‐up and vacuum bagging method. Woven glass fabric composites filled with particulate PHMS were observed to have better specific flexural strength and specific impact strength, as well as lower density, than those filled with particulate CC. Morphological features determined by scanning electron microscope (SEM) proved that the PHMS filler experienced good bonding in the VE matrix, a feature which contributed to the improvement in the properties of the composites. The incorporation of particulate fillers into the composites also influenced the storage modulus with a minimal effect on T_g. J. VINYL ADDIT. TECHNOL., 2010. © 2010 Society of Plastics Engineers     

Mechanical behaviour of highly filled lignin/polyethylene composites made by catalytic grafting

Highly filled lignin/polyethylene composites, with enhanced mechanical properties, were studied. Composites are prepared using the catalytic grafting technique of polyethylene on lignin particles. This technique improves wetting and dispersion of additives in the matrix as well as interactions between these two components. Mechanical properties (tensile and impact) and morphology of the composites were measured. The experimental results showed that highly filled HDPE/lignin composites (up to 73 vol%) could be produced by catalytic grafting. Tensile properties of the composites were quantitatively analysed using a micromechanical model for particulate composites based on an energy balance. Model predictions for Young's modulus are in excellent agreement with experimental results. The adjustable parameters of the model were varied from one composite to the other in a way which corresponds to the basic concepts related to particulate composites in general and to catalytic grafting in particular.     

Positron Lifetime Spectroscopy and Differential Scanning Calorimetric study of polystyrene‐based composites with fly ash,cenospheres, and calcium aluminosilicate as fillers

Polystyrene‐based composites with Fly ash, Cenospheres, and Calcium aluminosilicate as fillers have been examined for their mechanical and microstructure properties. Free volume measurements have been carried out using Positron Lifetime Spectroscopy to probe the microstructural features of the composites. Incorporation of fly ash, cenospheres, and calcium aluminosilicate improved the thermal properties of the composites due to increased T_g of the composites as revealed by the DSC data. Also, it was observed that the mechanical properties of calcium aluminosilicate filled composites improved more compared to fly ash and cenospheres filled composites. We attribute these favorable changes to the higher silica content of calcium aluminosilicate on account of possible interactions between the polymer matrix and silica and to some extent from particulate size. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Particulate composites from epoxy resin and fly-ash for the confinement of medium and low level radwastes

Water resistance of particulate fly-ash-epoxide composites, cured at low temperature by means of synthetic polyalkylenepolenepolyaminophenolic products, was tested at room temperature. Siliceous fly-ash (20% w/w) as filler reduces water penetration into the matrices, while saturation with water does not strongly affect the properties of the composites. The low value of the water diffusion coefficient through the material and the high mechanical properties of the particulate composites suggest further experimentation for its application in the confinement of low and medium activity nuclear wastes or of toxic chemical wastes.     

Effect of Granite Particle Size on the Properties of Al-7%Si-0.3%Mg/Granite Particulate Composites

The present study aims at investigating the effect of granite particle size on the properties of Al-7%Si-0.3%Mg/granite particulate composites. The composites were fabricated with two different size fractions of granite (− 38 + 0.5 μm and − 0.5 μm). Al-Si-Mg/granite particulate composites were produced using stir casting method with varying amount of granite particles from 0 to 12 wt% at 3 wt% intervals. X-ray fluorescence (XRF) analysis on the granite particulates as well as determination of density and mechanical properties were conducted. The results showed that density of Al-Si-Mg/granite particulate reinforced composites decreased considerably with particles loading. The results further revealed that with increase in granite particulates, a considerable rise in hardness accompanied with a significant decrease in tensile and impact strengths except at 3 wt% addition is achieved. The microstructural analyzes of the produced composites were studied using optical microscope (OM) and Scanning Electron Microscope (SEM). Noticeably, in the micrographs and images obtained, Mg₂Si and eutectic Si in α-Al matrix with granite particulates were observed.

     

Tribological and Microstructure Examination of Environmental Waste (Marble Dust) Filled Silicon Bronze Alloy for Wear Resistant Applications

In the present work, marble dust particulate filled silicon bronze (SiBr) alloy composites were fabricated in five different weight percentages (0 wt.%, 2.5 wt.%, 5 wt.%, 7.5 wt.% and 10 wt.% of MD). The main focus of this work was to study their physical and dry sliding wear behavior for rolling elements. The void contents of the particulate filled alloy composites decreased with the increase in marble dust content in the composites up to 7.5 wt.% of marble dust (MD). Similarly, the hardness of the filled composites showed an increasing trend with the increase in hard marble dust content in the alloy composites i.e. 119.25 Hv to 181.5 Hv for 0 wt.% to 7.5 wt.% addition of MD particulates. However, both the void content and hardness showed inferior properties in higher weight percentages of marble dust content. The Taguchi design of experimental (L ₂₅ orthogonal array) technique was implemented to find out the dry specific wear rate of the unfilled and marble dust filled SiBr alloy composites. A scanning electron microscopy (SEM) study was performed to study the wear mechanism of the worn composites along with atomic force microscopic (AFM) analysis to predict the surface profile of the worn particulate filled alloy composites.     

Mechanical properties and in vitro degradation behavior of additively manufactured phosphate glass particles/fibers reinforced polylactide

Phosphate glass/polylactide (PG/PLA) composites were additively manufactured via fused deposition modeling. The incorporation of 10 wt % PG particles improved the flexural modulus of composites by ~14% (3.53 GPa) but led to 5% reduction in flexural strength (92.4 MPa). The trend was more pronounced as the particle loading doubled. Comparing to a particulate composite of the same weight fraction, milled PG fibers (PGFs) reinforcement led to more effectively improved flexural modulus (~30%, 4.10 GPa). After 28 days of in vitro degradation in phosphate buffered saline, the particulate composites lost more than 30% of their initial mechanical properties, in contrast to less than 10% reduction of strength/modulus reported from fiber reinforced composites. The additively manufactured PG/PLA matrix composites have potential for application as customized bone fixation plates to repair the fractures under modest load-bearing applications. © 2019 The Authors. Journal of Applied Polymer Science published by Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48171.