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101.
PA66/EVA-g-MAH/绢云母复合材料的研究 总被引:3,自引:0,他引:3
为了弥补EVA-g-MAH增韧聚酰胺66时导致强度下降过多的缺点,采用绢云母作为增强剂,通过双螺杆挤出机采用熔融挤出法制备了聚酰胺66/EVA-g-MAH/绢云母复合材料。绢云母用偶联剂处理前后体系的界面形态的SEM照片表明,偶联剂提高了绢云母与树脂的界面结合力,改善了绢云母粒子在树脂中的分散状态,增加了两相的相容性。使用偶联剂后,PA66/EVA-g-MAH/绢云母体系较之未加绢云母体系和绢云母未用偶联剂处理体系,其拉伸强度、弯曲强度和热变形温度等性能都有提高,是一种综合性能较好的复合材料。 相似文献
102.
The thermoanalytical method offers a convenient means for testing a starting material before the end application. Differences in the kinetic parameters between neat and irradiated nylon 66 samples were estimated in the temperature range of 25°C–800°C by thermogravimetric analysis (TGA) and in the range of 25°C–300°C by differential scanning calorimetry (DSC). Under nitrogen flux the average activation energy for decomposition was in the range of 12.2–26.9 kcal/mol for the neat sample and 15.7–33.1 kcal/mol for the irradiated sample (250 h). Activation energy is affected by the process of bond breaking at the C? N bonds, which is the rate‐determining step of the decomposition in nylon 66. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 2146–2150, 2003 相似文献
103.
104.
Influence of thermal processing on the perfection of crystals in polyamide 66 and polyamide 66/clay nanocomposites 总被引:2,自引:0,他引:2
Yonglai Lu Ying Zhang Guobao Zhang Mingshu Yang Shouke Yan Deyan Shen 《Polymer》2004,45(26):8999-9009
A study of the changes in crystal perfection of polyamide 66 (PA66) and polyamide 66/clay nanocomposites (PA66CN) due to different thermal processing was carried out. We designed three series of thermal processing including melt-quench (MQ), post-annealing MQ sample (MQA), and melt–slow cooling–annealing (MSA). The annealing temperature was set as 180 or 210 °C, which is within Brill temperature range of PA66. Fourier transform infrared (FT-IR) spectroscopy and wide angle X-ray diffraction (WAXD) were employed to characterize the perfection in short-range order and long-range order structures, respectively. The results showed that the crystal perfection of PA66 and PA66CN with different thermal processing is quite different, and the changing fashions with thermal processing for different ordered structures are not similar. In this work, MSA is optimal thermal processing for high crystallinity and crystal perfection. Exfoliated nanoclay layers exert considerable impact on the perfection of long-range ordered structures, but little on that of short-range ordered ones. 相似文献
105.
用酸性染料染色后的尼龙66样品置于试验主染色机中,用合成丹宁进行后处理,浴比:1:20。合成丹宁的用量为2%(o.w.f),用醋酸调节PH至3.5-4。处理浴比的温度为40℃,然后升温至80℃,保温30分钟。测色结果显示:经处理后的染色尼龙66明显改善了其湿处理牢度和强物的沾色性能。 相似文献
106.
New kinetic model for polymerization process of nylon 66 salt solution based on functional group non-isoactivity
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The polymerization process of nylon 66 salt solution is a dynamically controlled process. Based on the assumption of unequal activity of functional carboxyl and amido groups, a new nylon 66 salt solution polymerization kinetic model was established by introducing the nylon salt dehydration reaction to the acid-catalyzed third-order reaction kinetic model and fitted to obtain the corresponding key kinetic parameters. The fitted salt dehydration reaction rate constant was 8.17×10-3 kg?mol-1?h-1, while the activation energy was 19859 cal?mol-1, respectively. Compared with Mallon model, the new developed model has a better fitting effect and can accurately predict the change of the polymerization process in a wider range of temperature and water content. Simulation results showed that salt dehydration reaction has an important effect on the polymerization process and the polymerization efficiency was relatively lower with higher concentration of nylon salt, especially under low temperature and high water content. Appropriately increase the reaction temperature or reduce the initial water content can accelerate the nylon salt dehydration reaction, thereby increasing the polymerization reaction efficiency. New nylon salt polymerization kinetics modeling method is not only applicable to nylon 66, but also to nylon 1212 and other salt solution polymerization systems. 相似文献
107.
硫酸钡填充改性聚酰胺66的研究 总被引:1,自引:0,他引:1
研究了聚酰胺66(PA66)/硫酸钡复合材料的形态结构和力学性能,探讨了硫酸钡的表面处理对复合材料形态结构的影响以及活化硫酸钡对复合材料力学性能的影响。结果表明,在20%(质量分数,下同)活化硫酸钡和5%的乙烯-辛烯共聚物熔融接枝马来酸酐共混改性PA66复合体系中,少部分的硫酸钡对PA66具有异相成核剂的作用,大部分的硫酸钡对PA66具有增韧作用。与未加活化硫酸钡的相比,材料的拉伸强度提高了11SPa、弯曲强度提高了12SPa,简支梁缺口冲击强度提高了9kJ/m^2。 相似文献
108.
109.
Influence of sepiolite nanoclay on the properties of the resulting join between poly(lactic acid) (PLA) and different Polyamide66 (PA66)/nanoclay nanocomposites was studied in this work. Six different polymer nanocomposites based on PA66 were manufactured through a melt compounding process by adding a fixed 1.64 wt % of a commercial IR absorber additive and the respective weight percentages of sepiolite to the polymer matrix. Several nanocomposite/PLA joints were finally performed by means of the transmission laser welding technology and the resulting weldings were characterized in terms of mechanical properties by performing peeling and shearing tests. Furthermore, both welded and mechanically tested samples were also analyzed by scanning electron microscopy in order to study the morphology of the weld seam. The results of the performed tests show that the addition of sepiolite to the PA66 improves the welding performance only in those cases in which the percentage of sepiolite of the nanocomposites is higher than 5 wt %. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46638. 相似文献
110.
Crystallization of polyamide 56/polyamide 66 blends: Non‐isothermal crystallization kinetics
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The non‐isothermal crystallization behaviors of PA56, PA66, and PA56/PA66 blends were studied by differential scanning calorimetry. The Jeziorny and Mo's methods were used to analyze their non‐isothermal crystallization kinetics. The results indicated that Mo's method was better to describe the experimental data in this work. The crystallization rate of PA56 was much slower than that of PA66. The crystallization rate of PA56/PA66 blend was speeded up significantly with the increasing PA66 content when the PA66 content was less than 30 wt %. Further increase in the PA66 content only leads to relatively less increase of the crystallization rate in the PA56/PA66 blends. Activation energies have been determined with Friedman method. The activation energy of PA56/PA66 blends is decreased and lower than that of PA56. PA66 may play a role of nucleating agent toward PA56 to make it crystallize more easily in PA56/PA66 blends. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46409. 相似文献