正交实验法研制MC尼龙/纳米CaCO3/石墨复合材料

通过正交实验法研究了MC尼龙/纳米CaCO3/石墨复合材料的配方,分析了纳米CaCO3、石墨、催化剂(NaOH)和助催化剂(TDI)对复合材料性能的影响。结果表明,添加适量的纳米CaCO3、石墨能提高复合材料的力学性能和维卡软化温度。以加权综合评分法得出复合材料的优化配方为:己内酰胺100份、NaOH0.17份、纳米CaCO32份、石墨0.40份、甲苯二异氰酸酯0.40份。     

环氧树脂改性MC尼龙/碳纤维/二硫化钼复合材料的研制

利用E-51环氧树脂(EP)改性MC尼龙,并以碳纤维(CF)粉为增强剂、二硫化钼(MoS2)为润滑剂、炭黑为增容剂,制备了MC尼龙复合材料.分别研究了EP,CF粉及MoS2的用量对MC尼龙复合材料性能的影响,并测试了MC尼龙复合材料与钢及铝合金摩擦时的耐磨损性能.结果表明,当MC尼龙用量为100份、EP为1.5份、CF粉为13份、MoS2为6.5份、炭黑为3.5份时,MC尼龙复合材料具有较好的力学性能和摩擦性能.相对于钢,该MC尼龙复合材料与铝合金摩擦时的耐磨损性能较好.     

环氧树脂改性MC尼龙的研究

针对单体浇铸尼龙(MC尼龙)缺口冲击强度低的缺点,采用环氧树脂(EP)对其进行改性。结果表明,EP改性MC尼龙的优化配方为已内酰胺100份、EP3份、NaOH 0．4份、甲苯二异氰酸酯1．0份,改性后MC尼龙的缺口冲击强度有明显提高,达30．68kJ／m^2。     

有机蒙脱土/聚氨酯/端羟基聚丁二烯液体橡胶纳米复合材料的制备

采用单体插层法制备了有机蒙脱土(OMMT)/聚氨酯(PU)/端羟基聚丁二烯液体橡胶(HTPB)纳米复合材料,通过正交试验研究了OMMT用量、甲苯二异氰酸酯(TDI)用量、加料方法及试验温度对复合材料作为胶黏剂使用时的T型剥离强度的影响.结果表明,OMMT/PU/HTPB复合材料的最佳制备条件为OMMT 3份(质量,下同),TDI18份,采用分步加料方式,在60℃下进行反应.所得复合材料作为胶黏剂使用时其T型剥离强度比未添加OMMT的空白试样高出218.1%.X射线衍射分析表明OMMT在PU/HTPB基质中达到了全剥离的程度.     

阻隔性尼龙611／有机蒙脱土纳米复合材料的研究

以11-氨基十一酸对蒙脱土(MMT)进行有机化改性,采用原位聚合法制备了尼龙611/有机蒙脱土(OM-MT)纳米复合材料.通过傅立叶变换红外光谱仪研究了OMMT及尼龙611/OMMT纳米复合材料的化学结构,使用扫描电子显微镜观察了纳米复合材料的形貌.详细考察了OMMT含量对尼龙611/OMMT纳米复合材料阻隔性能和力学性能的影响,探讨了OMMT的阻隔机理.结果表明,MMT经有机化改性后,其片层在尼龙基体中分散均匀,并与尼龙基体发生键合作用,使尼龙611分子的内聚力增强,分子链堆积程度提高,极大地提高了阻隔性能;OMMT质量分数为3%时,材料的拉伸强度达到最大值,但在常温、低温下冲击强度略有下降.     

MC尼龙6/TiO2原位纳米复合材料的制备及表征

利用阴离子原位聚合法制备了铸型尼龙6(MC尼龙6)／TiO2原位纳米复合材料,并对其结构与性能进行了表征。透射电子显微镜观察表明,TiO2以纳米级均匀分散于MC尼龙6中,其含量小于1份时近乎单分散,大于1份时则开始团聚。差示扫描量热法和X射线衍射法分析结果表明,纳米TiO2对MC尼龙6的结晶起到了异相成核作用,提高了MC尼龙6的结晶温度,但不改变MC尼龙6的α晶型结构;退火处理结果表明,高温退火或加入纳米TiO2,都有利于MC尼龙6基体中α晶型的生成,加快γ晶向α晶的转变。热重分析和力学性能测试表明,纳米TiO2提高了复合材料的热稳定性,其拉伸强度、冲击强度等也得到了不同程度的提高。     

不饱和聚酯/丙烯酸酯封端聚氨酯/改性蒙脱土复合材料的制备、结构与性能

制备了不饱和聚酯(UPR)／丙烯酸酯封端聚氨酯(ATPU)／改性蒙脱土(OMMT)复合材料，研究了其结构与性能。结果表明，ATPU／OMMT杂化物的比例与用量对UPR／ATPU／OMMT复合材料的结构与性能有很大的影响。当ATPU用量为15份、OMMT用量为2份时，复合材料的综合性能最佳。ATPU／OMMT杂化物对UPR具有增韧增强的协同效应。     

尼龙1010/十八烷基胺插层蒙脱土纳米复合材料研究

通过熔融加工制备了尼龙1010(PA1010)/十八烷基胺插层蒙脱土(OMMT)纳米复合材料。研究了OMMT含量对PA1010/OMMT纳米复合材料力学性能的影响。当OMMT质量分数为2%时,该纳米复合材料的综合力学性能达到最优。用TG、DMTA、DSC等分析方法对材料的热稳定性、结晶性能等进行了分析表征。结果表明,OMMT的加入提高了纳米复合材料的结晶温度、玻璃化转变温度和储能模量,但纳米复合材料的热稳定性稍有降低。     

丁腈橡胶/有机改性蒙脱土纳米复合材料的制备与性能

以丁腈橡胶(NBR)为基质、有机改性蒙脱土(OMMT)为填充剂,通过乳液共沉法制备了NBR/OMMT纳米复合材料,探讨了OMMT用量对NBR/OMMT复合材料的硫化特性、力学性能、耐老化及耐油性能的影响。结果表明,加入少量的OMMT可以提高NBR/OMMT纳米复合材料的力学性能和耐老化性能; 随着OMMT用量的增加,复合材料的流动性得到改善,且对其硫化特性也有影响; 当OMMT用量为7份(质量)时复合材料的综合性能最好。     

OMMT/PU/HTV硅橡胶纳米复合材料的制备与性能研究

采用硅烷偶联剂对钠基蒙脱土进行表面改性,制备有机蒙脱土(OMMT)/PU/热硫化(HTV)硅橡胶纳米复合材料,并对其性能进行研究.试验结果表明,与HTV硅橡胶相比,OMMT/PU/HTV硅橡胶纳米复合材料的热稳定性提高;当OMMT/PU用量为2份时,纳米复合材料的拉伸强度和拉断伸长率达到最大值.     

PC/ABS多相体系的制备及性能研究

用熔融挤出的方法制备了聚碳酸酯（PC）／N烯腈-丁二烯-苯乙烯共聚物（ABS）／有机蒙脱土（OMMT）合金，考察了OMMT用量对PC／ABS合金力学性能和加工性能的影响，观察了其相分布和OMMT的分散情况以及冲击断面的形貌，并分析了机理。结果发现．ABS相分散在PC基体中．绝大部分的OMMT分散在ABS相中，且部分呈纳米级分散；固定PC／ABS质量比为70／30，加入OMMT后体系的拉仲强度变化不大，冲击强度降低较大；OMMT用量为2phr时，弯曲性能最佳；随着蒙脱土用量的增加，熔体质量流动速率（MFR）先增大后降低，在OMMT用量为5phr时．流动性最好。     

NR／BR／OMMT纳米复合材料的研究（Ⅱ）纳米蒙脱土在工业配方中的应用

选用前期优选出的有机蒙脱土（OMMT）牌号,利用机械共混法制备了不同OMMT含量的天然橡胶（NR）/顺丁橡胶（BR）/OMMT纳米复合材料。利用透射电子显微镜研究了复合材料的亚微观结构,观察结果显示制备出了分散均匀的剥离型的NR/BR/OMMT纳米复合材料;力学性能测试表明,当OMMT的用量为3份时,其复合材料的综合力学性能最佳;耐溶剂实验表明,随着OMMT含量的逐渐增加,NR/BR/OMMT纳米复合材料的耐溶剂性能明显提高并不断提高;而OMMT在轮胎工业配方中的优异性能表明其在轮胎工业中具有良好的应用前景。     

有机蒙脱土/丁基橡胶/聚丙烯热塑性硫化胶的制备与性能

采用动态硫化法制备了有机蒙脱土(OMMT)/丁基橡胶(IIR)/聚丙烯(PP)热塑性硫化胶(TPV),考察了OMMT的用量和IIR/PP的质量比对TPV的物理机械性能、动态力学性能及热性能的影响.结果表明,当OMMT的用量为20份时,TPV的物理机械性能较佳,Payne效应最弱,OMMT均匀地分布在基体中,阻尼性能较好...     

Chlorinated butyl rubber/two-step modified montmorillonite nanocomposites: Mechanical and damping properties

Montmorillonite (MMT) was modified by ultrasound and castor oil quaternary ammonium salt intercalation method to prepare a new type of organic montmorillonite (OMMT). The surface structure, particle morphology, interlayer distance, and thermal behavior of the samples obtained were characterized. The modified OMMT was then added to chlorinated butyl rubber (CIIR) by mechanical blending, and a composite material with excellent damping properties was obtained. The mechanical experiment results of CIIR nanocomposites showed that the addition of OMMT improved their tensile strength, hardness, and stress relaxation rate. Compared with pure CIIR, when the content of OMMT was 5 phr (part per hundred of rubber), the tensile strength of the nanocomposite was increased by 677% and the elongation at break was also increased by 105.4%. The enhancement of this performance was mainly due to the dispersion of the nanosheets in CIIR rubber and the chemical interaction between the organoclay and the polymer matrix, which was confirmed by morphology and spectral analysis. OMMT also endowed a positive effect on the damping properties of CIIR nanocomposites. After adding 5 phr of OMMT, the nanocomposite owned the best damping performance, and the damping factor, tanδ_max, was 37.9% higher than that of pure CIIR. Therefore, the good damping and mechanical properties of these CIIR nanocomposites provided some novel and promising methods for preparing high-damping rubber in a wide temperature range.     

PP/黏土纳米复合材料的结构与性能

采用熔体插层法制备聚丙烯（PP）/有机黏土（OMMT）纳米复合材料。XRD和TEM的测试结果表明,采用熔体插层法制备的PP/OMMT复合材料是剥离型纳米复合材料。力学性能实验结果表明,相容剂的加入提高了PP与OMMT之间的相互作用,使其各项力学性能都得到了提高;PP/OMMT纳米复合材料的各项力学性能在有机黏土含量较小的情况下,就可以有较大幅度的提高;与纯PP相比,相容剂含量为10 phr、有机黏土用量为1 phr的聚丙烯基纳米复合材料具有最好的各项力学性能。     

SBR/OMMT纳米复合材料的制备及性能研究

以聚苯乙烯(PS)低聚物为相容剂，用熔体插层法制备SBR／有机蒙脱土(OMMT)纳米复合材料，并对其结构及性能进行研究。结果表明，PS大分子能够插入OMMT层间形成复合物；采用熔体插层法使PS／OMMT纳米复合物在SBR基体中实现纳米级分散，可间接实现OMMT在SBR基体中的纳米级分散；当填充5份OMMT时，SBR／OMMT纳米复合材料具有较好的物理性能。     

Effect of epoxy resin on morphology and physical properties of PVC/organophilic montmorillonite nanocomposites

Poly(vinyl chloride)/organophilic montmorillonite (PVC/OMMT) nanocomposites were prepared by means of melt blending. A liquid epoxy resin was used to aid PVC chains in intercalating into silicate layers. The effects of the preparation methods and epoxy resin contents on the melt intercalation of PVC were investigated. The morphology development, mechanical properties and optical properties of the PVC/OMMT composites were tested as functions of epoxy resin content and OMMT content. Wide‐angle X‐ray diffraction, transmission electron microscopy and scanning electron microscopy were used to characterize the morphology of the resulting composites. After being pretreated by the epoxy resin, the OMMT layers were largely intercalated into the PVC matrix, and even exfoliated at high epoxy resin content. The addition of epoxy resin led to a decrease in optical clarity of the composites but improved the processing stability, as indicated by yellowness index and haze measurement. However, the optical clarity of the composites containing 4 phr of epoxy resin (PVC/E‐OMMT) was improved by increasing the OMMT content, as shown by light transmission. Both the tensile strength and notched Izod impact strength of the PVC/E‐OMMT composites reached their maximum values when the OMMT content was 0.5 phr and the epoxy resin content was 2 phr. With further increase of the OMMT content and the epoxy resin content, the tensile strength decreased but was still higher than that of original PVC. The method of addition of epoxy resin had little effect on the physical properties but mainly influenced the morphology of PVC/OMMT nanocomposites. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2184–2191, 2003     

New approach for preparation of dry natural rubber nanocomposites through acid‐free co‐coagulation: Effect of organoclay content

Natural rubber (NR) vulcanizates exhibit good mechanical properties compared to vulcanizates of synthetic rubbers. Incorporation of a conventional filler at higher loadings to NR enhances its modulus, while reduction in tensile strength and elongation. This paper presents a new strategy for development of a NR‐clay nanocomposite with enhanced mechanical properties by incorporation of lower loadings (2–8 phr) of cetyl trimethyl ammonium bromide modified montmorillonite clay (OMMT‐C) under acid‐free environment. The effect of OMMT‐C loading on cure characteristics, rubber‐filler interactions, crosslink density, dynamic mechanical thermal properties, and mechanical properties were evaluated. Incorporation of OMMT‐C accelerated the vulcanization process and enhanced mechanical properties. X‐ray diffraction analysis and scanning electron microscopy images revealed that the formation of intercalated clay structures at lower OMMT‐C loadings, and clay aggregates at higher loadings. A nanocomposite at OMMT‐C loading of 2 phr exhibited the best balanced mechanical properties, and was associated with highest crosslink density and rubber–filler interactions. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46502.     

Influence of physical interaction between organoclay and poly(ethylene-co-vinyl acetate) matrix and effect of clay content on rheological melt state

In this study nanocomposites of poly(ethylene-vinyl acetate) (EVA) and organophilic montmorillonite clay (OMMT) (0, 2, 5 and 10 phr) were prepared. The nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), parallel plate rheometry and mechanical analysis. Oscillatory rheometry provided relaxation and retardation spectra, and the stress relaxation modulus and the creep compliance curves were obtained using the nonlinear regularization (NLREG) program. The results showed that 2 phr of OMMT were not sufficient to promote dispersion and exfoliation of the clay, although in the form of clay tactoids it had a catalytic effect on the degradation of EVA. The OMMT content had a strong influence on the thermal stability of chain segments containing vinyl acetate (VAc). The rheological study showed that at 5 phr there were substantial changes in the viscosity and energy dissipation of the sample, suggesting that at above 2 phr the nanocomposites become more stable leading to changes in the creep and viscoelastic properties of the material. The addition of OMMT promoted significant gains in terms of the mechanical properties, and thus a study on the clay content and flow behavior was carried out.     

Preparation,microstructure, and property of silicon rubber/organically modified montmorillonite nanocomposites and silicon rubber/OMMT/fumed silica ternary nanocomposites

Five different types of organically modified montmorillonites (OMMT), including Nanomor® I.30P, I.44P, I.24TL, I.34TCN, and I.31PS, were incorporated into silicone rubber (SiR), respectively, by using a melt‐blending method. The intercalation structure and spatial dispersion of OMMT in the obtained composites were characterized with wide‐angle X‐ray diffraction and transmission electron microscopy. The results revealed that the high‐polar organic intercalants or silane‐coupling agent might play the negative roles in the melt intercalation of SiR into OMMT, and the higher the initial interlayer spacing of the OMMT, the easier the intercalation. The intercalated structure in the SiR/I.44P OMMT nanocomposite has the largest interlayer spacing, and the spatial dispersion of OMMT is also the best. When OMMT loading is low (i.e., less than 10 phr), the dispersion of OMMT is poor. The dispersion of OMMT improves with increasing OMMT dosage, when the loading does not exceed 30 phr. The gas barrier property and the mechanical properties of the SiR are obviously improved by the incorporation of OMMT. The nitrogen gas permeability coefficient of the SiR nanocomposite containing 30 phr OMMT (I.44P) is lower than that of net SiR by 31%. To further improve the dispersion of OMMT in SiR, 20 phr fumed silica (FS) was added to the compound before mixing OMMT for increasing viscosity of the compound and mechanical shearing force during compounding OMMT. The resultant SiR/OMMT/FS ternary nanocomposites exhibit improved dispersion of OMMT and better gas barrier property than the binary counterparts. POLYM. COMPOS., © 2011 Society of Plastics Engineers.