氧化铝/环氧树脂/聚氨酯导热复合材料的制备及表征

采用硅烷偶联剂KH550对氧化铝表面进行改性,并以改性氧化铝为导热填料,以环氧树脂为基体树脂,自制的聚氨酯预聚体为柔性改性剂,制备了氧化铝/环氧树脂/聚氨酯导热复合材料。采用红外光谱对KH550改性氧化铝的结构进行了表征,探讨了影响复合材料热导率的主要因素,研究了改性氧化铝用量对复合材料力学性能的影响,并利用扫描电镜对复合材料的微观结构进行了观察。结果表明,KH550已通过化学键接枝在氧化铝表面。随着KH550改性氧化铝用量的增加,复合材料的拉伸强度逐渐增大,而导热率和断裂伸长率呈现先上升后下降的趋势。当改性氧化铝的用量为150 phr时,复合材料的导热率达到最大值0.66 W/(m·K),拉伸强度和断裂伸长率分别为37.2 MPa和1.62%。随着m(PUA)/m(EP)的增大,复合材料的导热率相应下降,适宜的m(PUA)/m(EP)为15/85。     

Preparation and characterization of acrylic latex/nano‐SiO2 composites

Acrylic/nano‐silica composite latexes were prepared by blending via high shear stirring (SS) or ball milling (BM) and in situ polymerization (IS). For comparison, composites filled with micro‐silica were also prepared. The mechanical and optical properties of the polymers formed by the composite latex filled with nano‐ or micro‐silica were investigated using an Instron testing machine, by dynamic mechanical analysis, ultraviolet–visible spectrophotometry and transmission electron micrography. The results showed that SS and BM methods could obtain better nanocomposite latex and polymers than the IS method, characterized by better dispersion of nanoparticles, higher tensile strength and T_g for SS and BM than for IS. The increase in absorbance and reduction in transmittance of UV (290–400 nm wavelength) were observed as nano‐silica content increased, whereas the UV absorbance or transmittance basically were kept unchanged for the composites filled with micro‐silica. © 2002 Society of Chemical Industry     

In situ polymerization and characterization of polyester‐based polyurethane/nano‐silica composites

Polyester‐based polyurethane/nano‐silica composites were obtained via in situ polymerization and investigated by Fourier‐transform infrared spectroscopy (FTIR), or FTIR coupled with attenuated total reflectance (FTIR‐ATR), Transmission electron microscopy (TEM), atomic force microscopy (AFM), an Instron testing machine, dynamic mechanical analysis (DMA) and ultraviolet‐visible spectrophotometry (UV‐vis). FTIR analysis showed that in situ polymerization provoked some chemical reactions between polyester molecules and nano‐silica particles. FTIR‐ATR, TEM and AFM analyses showed that both surface and interface contained nano‐silica particles. Instron testing and DMA data showed that introducing nano‐silica particles into polyurethane enhanced the hardness, glass temperature and adhesion strength of polyurethane to the substrate, but also increased the resin viscosity. UV‐vis spectrophotometry showed that nano‐silica obtained by the fumed method did not shield UV radiation in polyurethane films. Copyright © 2003 Society of Chemical Industry     

Preparation of nano‐TiO2/polystyrene hybride microspheres and their antibacterial properties

This study provided a facile method to prepare nano‐TiO₂/polystyrene hybride microspheres in ethanol solution. The formation of titanium dioxide (TiO₂) nanoparticles and hybrid microspheres were verified by FTIR, SEM, transmission electron microscopy, thermogravimetric analysis, and X‐ray powder diffraction. Monodispersed colloid TiO₂ nanoparticles with small particle sizes were obtained, and the average particle size could be effectively controlled from about 10 nm. The antibacterial activity of the organic microspheres and hybride microspheres was also investigated against Escherichia coli. They were able to efficiently inhibit the growth and the multiplication of E. coli under the UV. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Nonisothermal crystallization of PP/nano‐SiO2 composites

The kinetics of nonisothermal crystallization of polypropylene (PP) containing nanoparticles of silicon dioxide (SiO₂) were investigated by differential scanning calorimetry (DSC) at various cooling rates. Several different analysis methods were used to describe the process of nonisothermal crystallization. The results showed that the Ozawa equation and Mo's treatment could describe the nonisothermal crystallization of the composites very well. The nano‐SiO₂ particles have a remarkable heterogeneous nucleation effect in the PP matrix. The rate of crystallization of PP/nano‐SiO₂ is higher than that of pure PP. By using a method proposed by Kissinger, activation energies have been evaluated to be 262.1, 226.5, 249.5, and 250.1 kJ/mol for nonisothermal crystallization of pure PP and PP/nano‐SiO₂ composites with various SiO₂ loadings of 1, 3, and 5%, respectively. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1013–1019, 2004     

Preparation of nano‐Ag particles and their modification on the mechanical and dielectric properties of epoxy resin

Nano‐Ag particles stabilized by a hyperbranched polymer (HBP) template were prepared for modifying the epoxy resin. The effects of preparation condition on the size and size distribution of Ag colloidal particles were studied. The Ag@HBP particles were then compounded with the epoxy resin to obtain the Ag@HBP/epoxy composites and the mechanical and dielectric properties of these composites were investigated. Dynamic mechanical analysis results show that the composites have higher loss factors than does the unmodified epoxy resin, which indicate better dissipation of mechanical energy and hence better shock or impact resistance. Fracture morphology of the composite shows a toughness feature. From the dielectric test results, the breakdown strength and dielectric constant of the composites at room temperature are increased, which can be explained by the Coulomb block effect. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers     

BN／Al2O3／环氧树脂导热复合材料的制备与性能

分别采用氮化硼（BN）、氧化铝（Al2O3）和复配BN／Al2O3作为导热填料制备环氧树脂导热复合材料。结果表明,环氧树脂热导率随导热填料用量的增加而增大;同等用量下,BN／Al2O3／环氧树脂复合材料的导热性能均优于BN／环氧树脂和Al2O3／环氧树脂。当BN／Al2O3质量分4~50％[m（BN）／m（Al2O3）=3／1J,复合材料热导率为08194W／mK。此外,随BN／Al2O3用量的增加,环氧树脂的介电常数和介电损耗角正切增加,而弯曲强度和冲击强度则先增加后降低。     

Thermophysical properties of anhydride‐cured epoxy/nano‐clay composites

Polymer nano‐composites made with a matrix of anhydride‐cured diglycidyl ether of bisphenol A (DGEBA) and reinforced with organo‐montmorillonite clay were investigated. A sonication technique was used to process the epoxy/clay nano‐composites. The thermal properties of the nano‐composites were measured with dynamic mechanical analysis (DMA). The glass transition temperature T_g of the anhydride‐cured epoxy was higher than the room temperature (RT). For samples with 6.25 wt% (4.0 vol%) of clay, the storage modulus at 30°C and at (T_g + 15)°C was observed to increase 43% and 230%, respectively, relative to the value of unfilled epoxy. The clay reinforcing effect was evaluated using the Tandon‐Weng model for randomly oriented particulate filled composites. Transmission electron microscopy (TEM) examination of the nano‐composites prepared by sonication of clays in acetone showed well‐dispersed platelets in the nano‐composites. The clay nano‐platelets were observed to be well‐intercalated/expanded in the anhydride‐cured epoxy resin system. POLYM. COMPOS., 26:42–51, 2005. © 2004 Society of Plastics Engineers.     

Study of surface‐functionalized nano‐SiO2/polybenzoxazine composites

A series of the surface‐functionalized nano‐SiO₂/polybenzoxazine (PBOZ) composites was produced, and an attempt was made to improve the toughness of PBOZ material, without sacrificing other mechanical and thermal properties. A benzoxazine functional silane coupling agent was synthesized to modify the surface of nano‐SiO₂ particles, which were then mixed with benzoxazine monomers to produce the nano‐SiO₂‐PBOZ nanocomposites. The notched impact strength and the bending strength of the nano‐SiO₂‐PBOZ nanocomposites increase 40% and 50%, respectively, only with the addition of 3 wt % nano‐SiO₂. At the same load of nano‐SiO₂, the nano‐SiO₂‐PBOZ nanocomposites exhibit the highest storage modulus and glass‐transition temperature by dynamic viscoelastic analysis. Moreover, the thermal stability of the SiO₂/PBOZ nanocomposites was enhanced, as explored by the thermogravimetric analysis. The 5% weight loss temperatures increased with the nano‐SiO₂ content and were from 368°C (of the neat PBOZ) to 379°C or 405°C (of the neat PBOZ) to 426°C in air or nitrogen with additional 3 wt % nano‐SiO₂. The weight residue of the same nanocomposite was as high as 50% in nitrogen at 800°C. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Preparation and properties of nano‐CaCO3/acrylonitrile‐butadiene‐styrene composites

CaCO₃/acrylonitrile‐butadiene‐styrene (ABS) and CaCO₃/ethylene‐vinyl acetate copolymer (EVA)/ABS nanocomposites were prepared by melting‐blend with a single‐screw extruder. Mechanical properties of the nanocomposites and the dispersion state of CaCO₃ particles in ABS matrix were investigated. The results showed that in CaCO₃/EVA/ABS nanocomposites, CaCO₃ nanoparticles could increase flexural modulus of the composites and maintain or increase their impact strength for a certain nano‐CaCO₃ loading range. The tensile strength of the nanocomposites, however, was appreciably decreased by adding CaCO₃ nanoparticles. The microstructure of neat ABS, CaCO₃/ABS nanocomposites, and CaCO₃/EVA/ABS nanocomposites was observed by scanning electron microscopy. It can be found that CaCO₃ nanoparticles were well‐dispersed in ABS matrix at nanoscale. The morphology of the fracture surfaces of the nanocomposites revealed that when CaCO₃/EVA/ABS nanocomposites were exposed to external force, nano‐CaCO₃ particles initiated and terminated crazing (silver streak), which can absorb more impact energy than neat ABS. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Preparation of nano‐zinc oxide/EPDM composites with both good thermal conductivity and mechanical properties

In this article, nano‐zinc oxide (ZnO) filled ethylene propylene diene monomer (EPDM) composites are prepared, and the mechanical (static and dynamic) properties and thermal conductivity are investigated respectively, which are further compared with the traditional reinforcing fillers, such as carbon black and nano‐silica. Furthermore, influence of in‐situ modification (mixing operation assisted by silane at high temperature for a certain time) with the silane‐coupling agent Bis‐(3‐thiethoxy silylpropyl)‐tetrasufide (Si69) on the nano‐ZnO filled composites is as well investigated. The results indicate that this novel reinforcing filler nano‐ZnO can not only perform well in reinforcing EPDM but can also improve the thermal conductivity significantly. In‐situ modification with Si69 can enhance the interfacial interaction between nano‐ZnO particles and rubber matrix remarkably, and therefore contribute to the better dispersion of filler. As a result, the mechanical properties and the dynamic heat build‐up of the nano‐ZnO filled composites are improved obviously by in‐situ modification, without influencing the thermal conductivity. In comparison with traditioanl reinforcing fillers, in‐situ modified nano‐ZnO filled composites exhibit the excellent performance in both mechanical (static and dynamic) properties and better thermal conductivity. In general, our work indicates that nano‐ZnO, as the novel thermal conductive reinforcing filler, is suitable to prepare elastomer products serving in dynamic conditions, with the longer expected service life. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

环氧树脂/纳米纤维素复合材料的制备与性能研究

以木粉为原料制备纳米纤维素（CNF）,经甲基丙烯酸缩水甘油酯（GMA）改性后采用溶液共混法与环氧树脂（EP）复合,制得EP/CNF⁃GMA复合材料;通过对EP/CNF、EP/CNF⁃GMA复合材料力学性能、透光性能、亲水性、热稳定性和微观结构的表征,研究了CNF和GMA含量对复合材料性能的影响及其机理。结果表明,EP/CNF复合材料的拉伸强度、断裂伸长率、透光率随CNF含量的增大呈先增后减的变化趋势,亲水性随CNF含量的增大而增大;CNF含量为0.6 %（质量分数,下同）时,EP/CNF复合材料性能最优,拉伸强度为32.166 MPa,断裂伸长率为20.995 %,600 nm处透光率为79.8 %,接触角为77.34°。经GMA改性后,CNF与EP的相容性得到了改善,提升了EP/CNF复合材料的力学性能和热稳定性;随GMA含量的增加,EP/CNF⁃GMA复合材料的拉伸强度、断裂伸长率、透光率和亲水性均发生变化;GMA含量为4.8 %时EP/CNF⁃GMA复合材料性能最佳,拉伸强度为57.933 MPa,断裂伸长率为18.762 %,600 nm处透光率为86.3 %,接触角为81.42 °。     

丁苯橡胶/环氧树脂复合材料的制备及性能

采用机械共混法制得丁苯橡胶(SBR)/双酚A缩水甘油醚型环氧树脂(EP)复合材料,考察了橡胶硫化体系与EP固化体系的相互影响以及SBR/EP(质量比,下同)对复合材料结构和力学性能的影响。结果表明,SBR/EP复合材料中交联的形成分为橡胶交联和树脂交联网络2个阶段;橡胶硫黄硫化体系加速了EP的固化。复合材料中SBR与EP出现了相分离现象;当SBR/EP达到70/30时,EP形成连续相,复合材料成为具有双网络结构的橡塑复合材料;随着EP用量的增大,复合材料的拉伸强度、撕裂强度、100%定伸应力、硬度逐渐增大,扯断伸长率逐渐下降。     

Preparation and properties of composites based on melamine‐formaldehyde foam and nano‐Fe3O4

In this work, a novel melamine‐formaldehyde‐Fe₃O₄ foam was prepared from a mixture containing melamine‐ethanolamine‐formaldehyde resin, melamine‐glycol‐formaldehyde resin and carboxylated Fe₃O₄ nanoparticles by microwave foaming method. The two resins were characterized by ¹³C‐NMR, respectively. The structures of foams, mechanical and fire‐retardant properties were experimentally characterized separately by scanning electron microscopy, universal testing machine, limit oxygen index, thermogravimetry‐differential thermal analysis, and Fourier transform infrared spectra. The effects of the resin viscosity, emulsifier, nucleating agent, curing agent, silicone oil, microwave heating time and blowing agent on the structure of foam were investigated. Results showed that the properties of foam were decided by not only the molecular structure but also structure of foam, and the carboxylated Fe₃O₄ nanoparticles can improve the toughness and flame retardant properties of magnetic foam obviously from both aspects. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2688–2697, 2013     

己二酸环氧环己烷酯改性水溶性聚酯的制备及其膜性能研究

以对苯二甲酸(PTA)、乙二醇(EG)、间苯二甲酸-5-磺酸钠(SIPA)为主要原料,自制己二酸环氧环己烷酯(ACHD)为改性剂,制备了酸值为9～14 mg KOH/g、羟值为85～110 mg KOH/g、特性黏度为0.26～0.31 dL/g的己二酸环氧环己烷酯改性水溶性聚酯(MWPET),并进一步制备了厚度≤45...     

ZS－2阻燃不饱和聚酯树脂的制备

介绍了新型阻燃饱和聚酯树脂的合成方法。该树脂具有阻燃性能好、粘度适中、燃烧时发烟量少、制品透明、物理机械性能好等优点。     

Preparation and properties of plasticized starch/multiwalled carbon nanotubes composites

In this work we have studied the utilization of multiwalled carbon nanotubes (MWCNTs) as filler‐reinforcement to improve the performance of plasticized starch (PS). The PS/MWCNTs nanocomposites were successfully prepared by a simple method of solution casting and evaporation. The morphology, thermal behavior, and mechanical properties of the films were investigated by means of scanning electron microscopy, wide‐angle X‐ray diffraction, differential scanning calorimetry, and tensile testing. The results indicated that the MWCNTs dispersed homogeneously in the PS matrix and formed strong hydrogen bonding with PS molecules. Compared with the pure PS, the tensile strength and Young's modulus of the nanocomposites were enhanced significantly from 2.85 to 4.73 MPa and from 20.74 to 39.18 MPa with an increase in MWCNTs content from 0 to 3.0 wt %, respectively. The value of elongation at break of the nanocomposites was higher than that of PS and reached a maximum value as the MWCNTs content was at 1.0 wt %. Besides the improvement of mechanical properties, the incorporation of MWCNTs into the PS matrix also led to a decrease of water sensitivity of the PS‐based materials. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

纳米Al2O3/环氧树脂复合材料的制备及性能

在原位法制备纳米复合材料时，要使纳米粒子在树脂中分散均匀，必须首先获得稳定的单体悬浮体系。基于这一原理，本文通过对纳米Al2O3表面改性即选择合适的分散剂，获得稳定的纳米Al2O3/丙酮悬浮液，然后将环氧树脂溶解于其中，制得纳米Al2O3／环氧树脂复合材料。运用透射电子显微镜，观察了纳米Al2O3在环氧基体中的分散情况。分析并讨论了纳米Al2O3含量对该复合材料力学性能的影响。结果表明：利用稳定的悬浮体系能制得分散较为均匀的纳米复合材料，在纳米Al2O3含量为5％的情况下，纳米复合材料的力学性能达到最优。     

纳米分子筛/氧化铝复合材料的制备与表征

本文采用溶胶-凝胶法由自制的纳米分子筛和氧化铝制备纳米分子筛/Al2O3复合材料,做了制备纳米分子筛/Al2O3复合材料条件实验(如Al2O3凝胶浓度、煅烧温度、纳米分子筛和Al2O3配比等)。纳米分子筛/Al2O3复合材料进行了傅利叶变换红外光谱(FTIR)、X射线衍射仪(XRD)结构表征。测试了纳米分子筛/Al2O3复合材料的吸水率和吸油性,得出最佳吸水性和吸油性的制备条件。     

利用废聚酯制备对苯型不饱和聚酯树脂的研究

介绍了利用废聚酯制备对苯型不饱和聚酯树酯的方法。研究表明,该工艺简单合理,产品的耐腐蚀性、耐热性、机械性能和电性能优良