尼龙-6/粘土纳米复合材料阻燃性的锥形量热计研究

使用锥形量热计对尼龙－6／粘土纳米得合材料的阻燃性进行了实验研究。结果表明，使用融体插层制备的尼龙－6／粘土纳米得合材料，占粘土的百分含量为5％和7％时，纳米复合材料的热释放速率的峰值（PHRR）比尼龙－6分别下降32％和53％，与常规阻燃方法相比，具有优异的阻燃性能。     

尼龙6/粘土聚合物纳米复合材料的性能表征--(Ⅱ)结晶行为研究

使用Haake-90型双螺杆挤出机制备一系列粘土含量不同的尼龙6/粘土纳米聚合物复合材料,通过X射线衍射和差示扫描量热仪(DSC)研究其结晶行为.X射线衍射结果表明纳米粘土的加入改变了尼龙6的晶型.用修正Avnmi方程的Jeziorny法研究材料的非等温结晶动力学,发现纳米复合材料的半结晶时间t1/2缩短,纳米粘土对尼龙6有明显的异相成核作用.     

尼龙6/粘土聚合物纳米复合材料的性能表征--(Ⅰ)电性能研究

使用Haake-90型双螺杆挤出机制备一系列粘土含量不同的尼龙6／粘土纳米聚合物复合材料，测试其介电常数、介电损耗、介电稳定性能以及电击穿强度，并讨论了粘土含量对纳米复合体系电性能的影响。研究发现，加入纳米粘土后材料的介电常数、介电损耗明显减小，同时介电稳定性能有了大幅度提高．但电击穿强度无明显变化。     

尼龙6/POE/粘土纳米复合材料的研究

采用熔融方法制备出尼龙(PA)6/POE/粘土纳米复合材料,并对其力学性能及微观形态进行了研究.力学性能测试结果显示,PA6/POE/粘土纳米复合材料具有良好的力学性能,特别是其缺口冲击强度有显著提高,PA6/POE/粘土纳米复合材料有较好的韧性;广角X射线衍射分析显示,当有机粘土含量比较低时,有机粘土基本上剥离于PA6基体中;电子扫描电镜照片显示,POE相以岛状结构均匀分散于PA 6基体中.     

尼龙6/粘土聚合物纳米复合材料的性能表征——(I)电性能研究

使用Haake-90型双螺杆挤出机制备一系列粘土含量不同的尼龙6/粘土纳米聚合物复合材料,测试其介电常数、介电损耗、介电稳定性能以及电击穿强度,并讨论了粘土含量对纳米复合体系电性能的影响。研究发现,加入纳米粘土后材料的介电常数、介电损耗明显减小,同时介电稳定性能有了大幅度提高,但电击穿强度无明显变化。     

纳米粘土/环氧树脂复合材料的制备及力学性能研究

借助超声分散,采用固化处理制备了不同纳米粘土掺量(0,1％,3％,5％和7％(质量分数))的纳米粘土/环氧树脂复合材料,研究了纳米粘土掺量对复合材料性能的影响.通过X射线衍射(XRD)、力学性能测试、扫描电镜(SEM)等对复合材料进行了表征.结果表明,不同掺杂比例的纳米粘土和环氧树脂都均匀结合,纳米粘土掺量为7％(质量...     

尼龙6/POE/粘土纳米复合材料的形态、结构及性能研究

采用熔融方法制备了PA 6/POE/粘土纳米复合材料.PA 6/POE/粘土纳米复合材料具有良好的力学性能,其缺口冲击强度比PA 6有显著提高.研究结果表明,有机粘土剥离于PA 6基体中,POE相以岛状结构均匀分散于PA 6基体中;PA 6/POE/粘土纳米复合材料的储能模量比PA 6的低,并且随着有机粘土含量的增加而降低.PA 6/POE/粘土纳米复合材料的玻璃化转变温度(Tg)随着粘土含量的增加而升高,具有良好的热稳定性.     

环氧树脂/粘土纳米复合材料的制备及性能

本文对环氧树脂 粘土纳米复合材料的制备方法及影响粘土在环氧树脂基体中剥离程度的主要因素进行了综述 ,并介绍了该材料的性能及其发展趋势     

环氧树脂/粘土纳米复合材料的制备与性能研究

研究了有机蒙脱土在环氧树脂中的插层和剥离行为,制备了两种环氧树脂/蒙脱土纳米复合材料并测试了其力学性能。实验结果表明,环氧树脂与有机土的相容性好,二者混合时环氧树脂很容易插入到粘土层间。使用经不同有机阳离子处理的两种有机蒙脱土,分别制得插层型和剥离型环氧/粘土纳米复合材料,力学性能结果表明,剥离型纳米复合材料的性能优于同组成的插层型纳米复合材料。     

三元乙丙橡胶/蒙脱土纳米复合材料的制备、结构、性能与应用前景

利用熔融插层和三甲基十八烷基氯化铵插层剂改性钠基蒙脱土原土的方法,制备了EPDM/粘土纳米复合材料.X射线衍射(XRD)和透射电镜(TEM)的测试结果表明,所制备的复合材料为插层型.该纳米复合材料在有机蒙脱土的加入量为15份时,即具有优良的物理机械性能、较低的气透率和较高的动态屈挠以及优良的磨耗性能,在作为轮胎的内胎和子午线轮胎的气密层胶料的应用上具有广阔的前景.     

纳米有机蛭石/天然橡胶复合材料的制备及性能

以十六烷基三甲基溴化铵为插层剂, 用球磨法对蛭石进行了快速有机插层, 用过熔融共混法制备出纳米有机蛭石/ 天然橡胶复合材料。用XRD、SEM、TEM 对其微观结构进行了表征与分析, 证明蛭石以纳米片层分散在天然橡胶基体中。力学性能测试表明: 复合材料拉伸强度、扯断伸长率、300 %定伸强度、邵氏A 硬度、撕裂强度得到明显的改善。DMA、DSC 测试表明: 复合材料的模量具有明显的提高, 而玻璃化转变温度无明显变化。可见有机插层蛭石对天然橡胶的综合性能具有较明显的改善作用。      

Investigation of the nanomechanical properties of nylon 6 and nylon 6/clay nanocomposites at sub-ambient temperatures

The nanomechanical properties of nylon 6, nylon 6/exfoliated clay and nylon 6/non-exfoliated clay nanocomposites have been investigated from room temperature to ?10 °C in a controlled environment with humidity less than 1% RH. The hardness, elastic modulus and creep resistance of nylon 6 were improved in the nanocomposites across the temperature range. However, the effective reinforcement of the clay depended on the temperature due to the change between the glassy and transition states in the nylon. The exfoliated clay nanocomposite showed the greater improvements than in the non-exfoliated clay nanocomposite at all testing temperatures due to the improved constraint of the polymer chains by the clay platelets in the exfoliated structure. The surface mechanical properties of nylon 6 and the nanocomposites were also found to be highly sensitive to the moisture level during the tests; increasing the humidity in the room temperature tests resulted in a dramatic decrease in hardness and stiffness due to plasticisation by water molecules. The kinetics of the re-humidification process on nylon 6 were studied by monitoring the change in nanoindentation response. Analysis of the indentation creep revealed a significant change in the strain rate sensitivity when the humidity of the near-surface region probed by nanoindentation was in the vicinity of the glass transition.     

Epoxy based nanocomposites with fully exfoliated unmodified clay: mechanical and thermal properties

The unmodified clay has been fully exfoliated in epoxy resin with the aid of a novel ultrafine full-vulcanized powdered rubber. Epoxy/rubber/clay nanocomposites with exfoliated morphology have been successfully prepared. The microstructures of the nanocomposites were characterized by means of X-ray diffraction and transmission electron microscopy. It was found that the unmodified clay was fully exfoliated and uniformly dispersed in the resulting nanocomposite. Characterizations of mechanical properties revealed that the impact strength of this special epoxy/rubber/clay nanocomposite increased up 107% over the neat epoxy resin. Thermal analyses showed that thermal stability of the nanocomposite was much better than that of epoxy nanocomposite based on organically modified clay.     

Preparation,microstructure and thermal mechanical properties of epoxy/crude clay nanocomposites

To improve the performance/cost ratio of epoxy/clay nanocomposites, epoxy resin was reinforced with crude clay with the help of a silane modifier. The epoxy/crude clay nanocomposites were produced through a recently developed “slurry compounding” approach. The microstructure of the nanocomposites was characterized with X-ray diffraction (XRD), optical microscopy and transmission electron microscopy (TEM). The thermal mechanical properties were studied with dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA). It has been shown that only 5 wt% of silane modifier is required to facilitate the dispersion and exfoliation of crude clay in epoxy matrix. The storage moduli and thermal stability were improved with the addition of crude clay.     

有机磷氮系蒙脱土/LDPE纳米复合材料的制备及阻燃性能

以三氯氧磷和新戊二醇等为原料, 合成了一种新型磷氮型季铵盐(PAHAC), 通过红外光谱(FTIR)、 核磁共振氢谱(1H-NMR)和高分辨质谱(HRMS)表征化合物结构。利用PAHAC与钠基蒙脱土(Na-MMT)离子交换反应制备有机磷氮系蒙脱土阻燃剂(PAHACMMT)。FTIR和X射线衍射(XRD)研究表明: PAHAC通过离子交换对蒙脱土进行了有机化改性, 经20%质量分数的PAHAC改性后的MMT(20%PAHAC-MMT)层间距增至1.87nm, 20%PAHACMMT的热分解温度在310℃以上。透射电镜(TEM)分析结果表明, 20%PAHACMMT经LDPE熔融插层, 形成了插层剥离型纳米复合材料。锥形量热测试结果表明有机磷氮系蒙脱土/LDPE纳米复合材料具有良好的阻燃性能, 其中20%PAHACMMT(7%)/LDPE的热释放速率峰值(PHRR)比LDPE降低了21%, 热释放总量(THR)下降了9.5%。炭层的扫描电镜(SEM)分析结果表明, 20%PAHACMMT/LDPE燃烧后能形成致密的炭层, 起到良好的阻燃作用。      

不同动态硫化设备NBR/PA12热塑性硫化胶的制备和性能研究

采用开炼机、Haake密炼机和双螺杆挤出机3种动态硫化设备制备了丁腈橡胶(NBR)/尼龙12(PA12)热塑性硫化胶(TPV),研究了在相同配方下3种不同设备对NBR/PA12TPV微观相态结构、物理性能、热力学性质的影响,并考察了开炼机设备制备的TPV的重复加工性能。结果表明,3种设备制备的TPV为两相"海岛"结构,NBR为分散相,PA12为连续相;开炼机制备的TPV的NBR平均粒径最小且分布均匀,物理性能最佳;双螺杆挤出机制备的TPV的NBR硫化和剪切破碎不充分,平均粒径最大且分布宽,熔融焓最大;开炼机制备的TPV具有优异的重复加工性能,返炼次数增加,TPV的硬度逐渐增加,拉伸强度、撕裂强度先增加而后减小,耐油性能提高。