熔融插层制备聚合物／层状粘土纳米复合材料研究进展

从流变性能、加工操作过程对熔融插层制备聚合物纳米复合材料的影响、分散机理的研究进展等方面对熔融插层制备聚合物 /层状粘土进行了综述 ,并对今后的研究提出了展望。     

聚合物/纳米黏土复合材料的研究进展

简述了纳米黏土的结构特点,常见的有机化改性方法,介绍了可插层黏土的有机单体和聚合物类型。综述了聚合物/纳米黏土复合材料的制备方法,介绍了单体溶液插层、聚合物水溶液插层、乳液插层等溶液插层方法和单体熔融插层、聚合物熔融插层、熔融挤出插层等熔融插层方法。总结了聚合物/纳米黏土复合材料的国内外研究进展与应用现状,主要在汽车工业、包装材料、环境友好材料、新型工程材料等领域得到了广泛应用。     

熔融插层法制备聚合物复合材料的研究进展

对近年来熔融插层法制备聚合物复合材料的研究进展进行了综述。从动力学、热力学方面对插层结果进行了分析，总结了影响插层效果的因索；并归纳出插层以后复合材料性质的改善，最后展望了熔融插层法制备聚合物／粘土纳米复合材料。     

熔融插层法制备聚合物/蒙脱土纳米复合材料

综述了熔融插层法制备聚合物,蒙脱土纳米复合材料的新进展。熔融插层法制备聚合物,蒙脱土纳米复合材料具有设备简单、无单体限制和不需要溶剂的优点,并从热力学角度探讨了熔融插层法制备聚合物,蒙脱土纳米复合材料的不足以及改进措施。     

聚丙烯/蒙脱土纳米复合材料的研究进展

对聚丙烯(PP)／蒙脱土(MMT)纳米复合材料的国内外研究进展进行综述,介绍了PP/MMT纳米复合材料的制备原理和制备方法。包括原位插层聚合法、聚合物溶液插层法、聚合物熔融插层法、溶胶一凝胶法,重点介绍了聚合物熔融插层法的研究进展。聚合物熔融插层法具有操作简单、无需处理过多溶剂的优点,避免了环境和能源问题,更易于工业化。最后对PP／MMT纳米复合材料的未来发展进行了展望。     

聚合物/纳米粘土插层复合材料的研究进展

综述了插层法制备聚合物／纳米粘土复合材料的新进展。根据插层机理和方法的差别，插层法主要分为溶液插层和熔融插层两类、总结了使用二次插层和乳液聚合制备聚合物基纳米复合材料的新方法，展望了聚合物／纳米粘土复合材料的开发及应用前景。     

物理插层复合在聚合物/蒙脱土纳米复合材料制备中的应用

描述了物理插层复合的热力学原理,介绍了插层复合中插层剂的种类和聚合物／蒙脱土纳米复合材料的表征方法。综述了近年来国内外应用溶液插层和熔融插层两种物理插层法制备聚合物／蒙脱土纳米复合材料的具体实例。     

熔融插层法制备聚合物/纳米蒙脱土的研究进展

简要介绍了熔融插层法制备聚合物／纳米蒙脱土复合材料的研究进展。结合热力学和动力学的分析，概括了熔融插层法一些理论上的研究进展。总结了目前关于熔融插层法制备聚合物／纳米蒙脱土复合材料及其表征的最新研究成果。     

直接熔融复合制备聚酰胺6／未改性蒙脱土纳米复合材料

在普通双螺杆挤出机上，基于未改性蒙脱土和聚酰胺6的直接熔融复合制备了纳米复合材料。通过插层剂的合理选择及不同插层剂的复配使用，可以得到具有插层刷离分散形态的聚酰胺6／未改性蒙脱土纳米复合材料。力学性能测试结果表明，有可能通过在聚酰胺6／未改性蒙脱土复合体系中插层剂的选择与调配实现同时增加聚酰胺6基体的强度和韧性的目的。在特定的插层剂复配条件下，复合材料的弯曲强度较基体增加20％，弯曲模量增加29％，同时干态冲击强度的增幅达70％以上。此外，还讨论了聚酰胺6／未改性蒙脱土复合体系的动态力学行为和流变性能。     

熔融插层法制备聚合物/黏土纳米复合材料研究进展

对国内外熔融插层法制备聚合物／黏土纳米复合材料(PCN)的研究进展进行了介绍。介绍了影响PCN结构形态的几种因素;对熔融插层法制备PCN的热力学、动力学的研究进行了总结;介绍了熔融插层的机理和几种理论模型。并对聚合物／黏土纳米复合材料的开发及应用前景作出了展望。     

聚乳酸/无机填料复合材料结构与性能的研究

采用密炼器熔融共混法,将聚乳酸(PLA)分别与碳酸钙(CaCO3)、蒙脱土(MMT)及滑石粉(Talc)共混制备成生物降解复合材料,研究了PLA/无机填料共混物的力学性能、断面微观结构及结晶性能。结果表明:CaCO3、MMT和Talc均降低了PLA的断裂伸长率;Talc和CaCO3对PLA的拉伸强度影响不大,MMT明显降低了PLA的拉伸强度;Talc和CaCO3相对MMT在PLA基体中的分散较均匀;CaCO3和MMT改善PLA结晶性能的效果不明显,而Talc大大提高了PLA的结晶性能使,PLA的结晶温度下降约20℃结,晶度提高近3%。     

Using supercritical carbon dioxide in preparing carbon nanotube nanocomposite: Improved dispersion and mechanical properties

Improvements in carbon nanotube (CNT) dispersion and subsequent mechanical properties of CNT/poly(phenylsulfone) (PPSF) composites were obtained by applying the supercritical CO₂ (scCO₂)‐aided melt‐blending technique that has been used in our laboratory for nanoclay/polymer composite preparation. The preparation process relied on rapid expansion of the CNTs followed by melt blending using a single‐screw extruder. Scanning electronic microscopy results revealed that the CNTs exposed to scCO₂ at certain pressures, temperatures, exposure time, and depressurization rates have a more dispersed structure. Microscopy results showed improved CNT dispersion in the polymer matrix and more uniform networks formed with the use of scCO₂, which indicated that CO₂‐expanded CNTs are easier to disperse into the polymer matrix during the blending procedure. The CNT/PPSF composites prepared with scCO₂‐aided melt blending and conventional melt blending showed similar tensile strength and elongation at break. The Young's modulus of the composite prepared by means of conventional direct melt blending failed to increase beyond the addition of 1 wt% CNT, but the scCO₂‐aided melt‐blending method provided continuous improvements in Young's modulus up to the addition of 7 wt% CNT. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers     

蒙脱土对聚合物颜色及力学性能的影响

通过熔融共混法制备了聚丙烯／蒙脱土(MMT)、(苯乙烯／丁二烯／苯乙烯)共聚物／MMT及聚氯乙烯／MMT共混物。研究了MMT在聚合物加工过程中,以及在热老化过程中对聚合物耐老化性能的影响。在不同混炼时间及热老化时间下,共混物的黄度指数相对纯聚合物有明显提高。力学性能的测试结果也表明,MMT对聚合物的老化有一定促进作用。     

Crystallization behavior of PA‐6 clay nanocomposite hybrid

Polyamide‐6 (PA‐6)/clay (modified montmorillonite) hybrid was synthesized by melt blending at high shear stress. ²⁷Al‐NMR of solid state shows that the clay is not modified after melt blending. Using wide‐line ¹H‐NMR and TEM, it is demonstrated that the nanocomposite exhibits mainly an exfoliated structure. It is shown that the modified montmorillonite induces the crystallization of PA‐6 predominantly in γ‐form. The presence of clay in PA‐6 increases the polymer crystallization temperature, and decreases its melting point. These phenomena show that a certain number of interactions develop near the reinforcing material, and that the latter plays a particular role of nucleating agent. However, the crystallization is not spherulitic and the assumption of macromolecular orientation in the vicinity of the clay is demonstrated by the observations carried out in DSC and AFM. These particular properties of orientation will have a particular importance on the mechanical behavior of the nanocomposite material. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2416–2423, 2002     

PA6/蒙脱土熔融插层复合材料结构与性能分析

通过熔融共混法插层复合制备了聚酰胺(PN)6／蒙脱土纳米复合材料，测试了力学性能并对不同蒙脱土含量的PA 6／蒙脱土纳米复合材料进行了对比。实验表明，通过熔融插层可使PN 6基体插层于蒙脱土中，所得到的复合材料的性能较PN 6有很大提高。蒙脱土特殊的层状结构使得利用熔融共混在机械力的作用下插层到纳米级复合材料成为可能。     

Vapor barrier properties of polycaprolactone montmorillonite nanocomposites: effect of clay dispersion

Different compositions of poly(ε-caprolactone) (PCL) and (organo-modified) montmorillonite were prepared by melt blending or catalyzed ring opening polymerization of ε-caprolactone. Microphase composites were obtained by direct melt blending of PCL and sodium montmorillonite (MMT-Na⁺). Exfoliated nanocomposites were obtained by in situ ring opening polymerization of ε-caprolactone with an organo-modified montmorillonite (MMT-(OH)₂) by using dibutyltin dimethoxide as an initiator/catalyst. Intercalated nanocomposites were formed either by melt blending with organo-modified montmorillonite or in situ polymerization within sodium montmorillonite. The barrier properties were studied for water vapor and dichloromethane as an organic solvent. The sorption (S) and the zero concentration diffusion coefficient (D₀) were evaluated for both vapors. The water sorption increases with increasing the MMT content, particularly for the microcomposites containing the unmodified MMT-Na⁺. The thermodynamic diffusion parameters, D₀, were compared to the value of the parent PCL: both microcomposites and intercalated nanocomposites show diffusion parameters very near to PCL. At variance exfoliated nanocomposites show much lower values, even for small montmorillonite content. In the case of the organic vapor, the value of sorption at low relative pressure is mainly dominated by the amorphous fraction present in the samples, not showing any preferential adsorption on the inorganic component. At high relative pressure the isotherms showed an exponential increase of sorption, due to plasticization of the polyester matrix. The D₀ parameters were also compared to those of the unfilled PCL; in this case, both the exfoliated and the intercalated samples showed lower values, due to a more tortuous path for the penetrant molecules.     

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。     

SBS/蒙脱土复合材料的制备及其性能Ⅱ.复合材料的性能

分别采用大分子溶液插层法和大分子熔融插层法制备了苯乙烯-丁二烯-苯乙烯共聚物（SBS）／蒙脱土纳米复合材料．研究了材料的力学性能。纳米结构的形成对复合材料的性能产生显著影响,少量蒙脱士的引入可以明显改善SBS／蒙脱土复合材料的力学性能。无论溶液插层法制备的星型SBS／蒙脱土纳米复合材料,还是熔融插层法制备的线型SBS／蒙脱土纳米复合材料,其拉伸强度和断裂伸长率都同时增加。其中,溶液插层法制备的纳米复合材料的拉伸强度和断裂伸长率分别较纯SBS增加了75％和55％;熔融法制备的纳米复合材料的托伸强度和断裂伸长率分别较纯SBS增加了70％和18％。