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尼龙6/蒙脱土纳米复合材料的结晶行为 总被引:63,自引:4,他引:63
用广角X 射线衍射(WAXD)、差示扫描量热仪(DSC)、小角激光散射(SALS)等手段研究了尼龙6/蒙脱土纳米复合材料的结晶行为.结果表明分散在尼龙6基体中的蒙脱土纳米粒子起成核剂的作用.蒙脱土的表面改性增加了蒙脱土和尼龙6分子之间的界面粘接,它具有阻碍尼龙6结晶的作用,使结晶活化能增加 相似文献
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尼龙66/蒙脱土复合材料结晶行为的研究 总被引:8,自引:0,他引:8
在密炼机中采用熔融共混法制备蒙脱土重量分数为 2 5 %、4 5 %的尼龙 6 6 /蒙脱土复合材料 .通过DSC法对非等温结晶行为及在 2 2 8~ 2 4 0℃范围内的等温结晶行为进行研究 ,并与纯尼龙 6 6进行比较 .从其等温和非等温结晶行为的研究表明 ,蒙脱土起成核剂的作用 ,它的填入使尼龙 6 6结晶速率提高 ,但填料与基体间的相互作用使其链段运动困难 ,结晶活化能提高 ;在研究的填料含量变化范围内 ,结晶行为变化不大 ,并且找到该复合材料在 2 2 8~ 2 34℃范围结晶对温度的不敏感区 ;对非等温结晶过程分析 ,刘结平 莫志深方程是适用的 ,而Ozawa方程则是不适用的 . 相似文献
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将有机化的蒙脱土与尼龙6(PA6)在Haake共混机中共混,制备出尼龙6/蒙脱土纳米复合材料(PA6N);对尼龙6/蒙脱土纳米复合材料和纯尼龙6分别进行差示扫描量热法非等温结晶试验,以了解蒙脱土在尼龙6/蒙脱土纳米复合材料中的成核作用、扩大尼龙6在包装领域的应用范围.与此同时,采用偏光显微镜测定了样品的结晶形态;采用紫... 相似文献
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用DSC研究了尼龙 12 12 ,尼龙 6及其共混体系的非等温结晶行为 .结果表明 ,加工历史对尼龙的结晶和熔融行为影响很大 .经双螺杆挤出机挤出的尼龙 12 12和尼龙 6 ,由于应力诱导分子链取向 ,其结晶温度都有不同程度的提高 ,且表现出多重熔融现象 .在共混体系中 ,尼龙 12 12分子在共混物的界面上异相成核结晶 ,提高了其结晶温度 ,但酸酐化SEBS的加入抑制了分子链的运动又使其结晶温度降低 .共混体系降低了尼龙12 12的熔融温度 ,并使得其高熔点的熔融峰逐渐消失 ;而尼龙 6的熔融行为基本上没有变化 . 相似文献
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Qing‐Xin Zhang Zhong‐Zhen Yu Mingshu Yang Jun Ma Yiu‐Wing Mai 《Journal of Polymer Science.Polymer Physics》2003,41(22):2861-2869
Nylon‐66 nanocomposites were prepared by melt‐compounding nylon‐66 with organically modified montmorillonite (MMT). The organic MMT layers were exfoliated in a nylon‐66 matrix as confirmed by wide‐angle X‐ray diffraction (WAXD) and transmission electron microscopy. The presence of MMT layers increased the crystallization temperature of nylon‐66 because of the heterogeneous nucleation of MMT. Multiple melting behavior was observed in the nylon‐66/MMT nanocomposites, and the MMT layers induced the formation of form II spherulites of nylon‐66. The crystallite sizes L100 and L010 of nylon‐66, determined by WAXD, decreased with an increasing MMT content. High‐temperature WAXD was performed to determine the Brill transition in the nylon‐66/MMT nanocomposites. Polarized optical microscopy demonstrated that the dimension of nylon‐66 spherulites decreased because of the effect of the MMT layers. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2861–2869, 2003 相似文献
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Nilay K. Pramanik Ramsankar Haldar Utpal K. Niyogi MD. Sarwar Alam 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(4):296-307
The non-isothermal crystallization kinetics was studied by differential scanning calorimetric analysis on nylon 66 and e-beam irradiated nylon 66 at different cooling rates. The Modified Avrami equation, the Ozawa equation and the Combined Avrami-Ozawa equation were applied to study the kinetics of non-isothermal crystallization of nylon 66. The crystallization behavior of pristine nylon 66 polymer was compared with that of e-beam irradiated nylon 66 and observed that the kinetics of non-isothermal crystallization of nylon66 was affected largely upon e-beam irradiation. E-beam irradiation not only decreased the crystallization temperature of nylon 66, but influenced the mechanism of nucleation and crystal growth and reduced the overall crystallization rate of nylon 66 also. The crystallization activation energy calculated by the Kissinger method for irradiated nylon 66 was lower than that of pristine nylon 66. 相似文献
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Zhong‐Zhen Yu Mingshu Yang Qingxin Zhang Chungui Zhao Yiu‐Wing Mai 《Journal of Polymer Science.Polymer Physics》2003,41(11):1234-1243
Nylon‐66 nanocomposites were prepared by melt‐compounding nylon‐66 with an alkyl ammonium surfactant pretreated montmorillonite (MMT). The thermal stability of the organic MMT powders was measured by thermogravimetric analysis. The decomposition of the surfactant on the MMT occurred from 200 to 500 °C. The low onset decomposition temperature of the organic MMT is one shortcoming when it is used to prepare polymer nanocomposites at high melt‐compounding temperatures. To provide greater property enhancement and better thermal stability of the polymer/MMT nanocomposites, it is necessary to develop MMT modified with more thermally stable surfactants. The dispersion and spatial distribution of the organic MMT layers in the nylon‐66 matrix were characterized by X‐ray diffraction. The organic MMT layers were exfoliated but not randomly dispersed in the nylon‐66 matrix. A model was proposed to describe the spatial distribution of the organic MMT layers in an injection‐molded rectangular bar of nylon‐66/organic MMT nanocomposites. Most organic MMT layers were oriented in the injection‐molding direction. Layers near the four surfaces of the bar were parallel to their corresponding surfaces; whereas those in the bulk differed from the near‐surface layers and rotated themselves about the injection‐molding direction. The influence of the spatial distribution of the organic MMT on crystallization of nylon‐66 was also investigated. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1234–1243, 2003 相似文献
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Two master-batches,polyamide 66 (PA66)/organo-montmorillonite (OMMT) and polyamide 6 (PA6)/OMMT, prepared by melt compounding with methyl methacrylate (MMA) as co-intercalation agent,have been used to prepare nearly exfoliated PA661montmorillonite (MMT) nanocomposites.The resulting nanocomposites are compared in view of their morphology and properties.Nano-scale dispersion of OMMT is realized in both types of nanocomposites,as revealed by XRD,TEM and Molau tests.PA66/MMT nanocomposites having superior me... 相似文献
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Dong Wook Chae Ki Hyun Lee Byoung Chul Kim 《Journal of Polymer Science.Polymer Physics》2006,44(2):371-377
Effects of ferrite nanoparticles (0.1–20 wt %) on the rheological and other physical properties of nylon‐66 were investigated. The presence of ferrite nanoparticles less than 1 wt % increased the crystallization temperature (Tc) by 4.2 °C with ferrite content, but further addition decreased Tc. The onset temperature of degradation was increased by 7.3 °C at only 0.1 wt % loading of ferrite, after which the thermal stability of nylon‐66 was decreased with ferrite content. The incorporation of ferrite nanoparticles more than 5 wt % increased the dynamic viscosity (η′) with the loading level. Further, it produced notably shear thickening behavior in the low frequency, after which high degree of shear thinning was followed with ferrite content. In the Cole–Cole plot, the nanocomposites with ferrite lower than 5 wt % presented a single master curve, while further addition gave rise to a deviation from the curve. The relaxation time (λ) was increased with ferrite content and the difference of λ between nylon‐66 and its nanocomposite was greater at lower frequency. The tensile strength was a little increased up to 1 wt % loading, after which it was decreased with increasing the loading level. In addition, the introduction of the nanoparticles increased tensile modulus and decreased the ductility with ferrite content. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 371–377, 2006 相似文献
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In this paper, a new type of organophilic montmorillonites, co-treated by octadecylammonium and aminoundecanoic acid, were synthesized and applied to prepare nylon 66/montmorillonite nanocomposites via melt compounding in a twin extruder. WAXD and TEM characterization indicate that a disordered structure was derived and the montmorillonite platelets dispersed in nanoscale in the nylon 66 matrix. The nanocomposites with co-treated montmorillonite display comparatively higher strength and modulus compared to nylon 66 matrix. 相似文献
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MELTING CRYSTALLIZATION BEHAVIOR OF NYLON 66 总被引:2,自引:0,他引:2
Qing-xin Zhang Zhi-shen Mo State Key Laboratory of Polymer Physics & Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun China 《高分子科学》2001,(3):237-246
Analysis of isothermal and nonisothermal crystallization kinetics of nylon 66 was carried out using differentialscanning calorimetry (DSC). The commonly used Avrami equation and that modified by Jeziorny were used, respectively, tofit the primary stage of isothermal and nonisothermal crystallizations of nylon 66, In the isothermal crystallization process,mechanisms of spherulitic nucleation and growth were discussed. The lateral and folding surface free energies determinedfrom the Lauritzen-Hoffman treatment are σ= 9.77 erg/cm~2 and σ_e= 155.48 erg/cm~2, respectively; and the work of chainfolding is q = 33.14 kJ/mol. The nonisothermal crystallization kinetics of nylon 66 was analyzed by using the Mo methodcombined with the Avrami and Ozawa equations. The average Avrami exponent n was determined to be 3.45, Theactivation energies (ΔE) were determined to be -485.45 kJ/mol and -331.27 kJ/mol, respectively, for the isothermal andnonisothermal crystallization processes by the Arrhenius and the Kissinger methods. 相似文献
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采用测定转化率和特性粘数、红外光谱、偏光显微镜、扫描电镜和DSC等方法,研究了结晶尼龙66盐固态缩聚过程的反应历程、初生态尼龙66的结晶形态及其热行为与热历史的关系。实验结果表明,在缩聚过程中尼龙66盐结晶的缺陷可以诱发大分子相的成核,并出现外延结晶过程。发现,初生态尼龙66呈现出原纤状结构状态,且原纤的取向取决于反应条件;讨论了初生态尼龙66在DSC谱上所出现的熔融双峰现象。 相似文献