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《山东化工》2017,(19)
研究了玻璃纤维(GF)、自制马来酸酐接枝聚丙烯(PP-g-MAH)和螺杆转速对短玻纤增强聚丙烯(PP/SFT)复合材料力学性能和微观形貌的影响。结果表明:随着GF用量增加,复合材料的弯曲模量和缺口冲击强度增大,拉伸强度先增大后降低,PP/SFT复合材料断面呈现脆性断裂;随着增容剂PP-g-MAH用量增加,拉伸强度和缺口冲击强度先增加后降低,弯曲模量基本不变;当PP,GF和PPg-MAH的质量比为50∶50∶3时,其综合性能最优,拉伸强度为113.0 MPa,冲击强度为15.8kJ/m~2,复合材料断面呈现韧性断裂;螺杆转速和剪切增大会降低纤维平均长度和复合材料的力学性能。 相似文献
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在小试研究的基础上进行反应挤出聚酰胺6/蒙脱石复合材料中试研究,重点考察脱水工艺条件对聚合的影响,螺杆转速对复合材料力学性能的影响,蒙脱石含量对复合材料力学性能的影响.中试结果显示:双螺杆挤出机各段的温度在140℃左右,随着螺杆转速的提高,复合材料的断裂伸长率、缺口冲击强度出现下降,拉伸强度、弯曲强度和弯曲模量增大,中试螺杆转速在110 r/min;随着蒙脱石含量的增加,复合材料的拉伸强度、弯曲模量呈升高趋势,而缺口冲击强度呈下降趋势,最佳蒙脱石含量为3%~4%;小试与中试的脱水工艺条件基本相当,中试产品颜色和力学性能好于小试产品. 相似文献
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以拉伸流变为主的叶片挤出机与传统的螺杆挤出机有很大的不同,螺杆挤出机是以剪切流场为主的加工方式,而在叶片挤出机中则是以拉伸流变起主导作用。利用自主研发的叶片挤出机制备了剑麻纤维(SF)/聚丙烯(PP)复合材料。探讨了叶片挤出机加工转速以及SF含量对物料在挤出机中停留时间以及复合材料力学性能的影响。结果表明:物料停留时间随加工转速升高呈非线性减少趋势,随SF含量升高呈非线性增加趋势;在相同的SF含量下,复合材料的拉伸强度和拉伸模量随着转速的提高而增加,当转速提高到90 r/min时,拉伸强度和拉伸模量分别比转速为30 r/min时提高了21.3%和11.6%;在相同转速下,复合材料的拉伸强度随着SF含量增加而降低,而拉伸模量则随SF含量增加而增加。 相似文献
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废聚丙烯/废轮胎胶粉/废尼龙短纤维复合材料Ⅱ.工艺条件 总被引:2,自引:0,他引:2
采用反应挤出方法制备了废聚丙烯/废轮胎胶粉/废尼龙短纤维(WPP/GRT/WSF)复合材料,讨论了螺杆转速、机头温度对WPP/GRT/WSF复合材料力学性能的影响。结果表明,当螺杆转速为15r/min,机头温度为185~195℃时,WPP/GRT/WSF复合材料的力学性能达到最佳,拉伸强度为13.6MPa,冲击强度为25.2kJ/m^2。按照最佳配方和工艺挤出管材的拉伸强度为4,6MPa,冲击强度为5.4kJ/m^2,爆破压力为0.69MPa。 相似文献
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采用挤出-熔体拉伸-淬冷法制得了聚乙烯/聚对苯二甲酸丁二醇酯(PE/PBT)原位复合纤维和原位增强材料,研究了挤出后熔体拉伸速度对PBT微纤形态和复合纤维强度的影响以及原位成纤复合材料的性能。结果表明:随着熔体拉伸速度的增加,PBT微纤的平均直径先减小后增大,复合纤维相对强度基本呈上升趋势。在注塑样条中,随着PBT含量的增加,材料的拉伸强度先增大后减小,但比普通共混材料的力学性能好。 相似文献
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The effects of processing conditions on fiber length degradation were investigated in order to produce composites with higher performance. Nylon‐6 was compounded with glass fibers in a twin‐screw extruder for various combinations of screw speed and feed rate. Collected samples were injection molded and Izod impact and tensile tests were performed in order to observe the effect of fiber length on the mechanical properties. Also, by using the extruded and injection molded smaples, fiber length distribution curves were obtained for all the experimental runs. Results show that when the shear rate is increased through the alteration of the screw speed and/or the feed rate, the average fiber length decreases. Impact strength, tensile modulus and tensile strength increase, whereas elongation at break decreases with the average fiber length. 相似文献
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高密度聚乙烯熔纺纤维的拉伸工艺 总被引:6,自引:0,他引:6
相对分子质量为14万的高密度聚乙烯(HDPE)通过螺杆挤出机熔纺成形,然后经过高温超拉伸可制成强度为9.7cN/dtex的中强聚乙烯纤维。讨论了拉伸温度、拉伸比对纤维力学性能的影响,并通过声速取向、热分析(DSC)、广角X射线衍射(WAXD)和纤维力学性能的测试研究了拉伸过程中聚乙烯纤维结构与性能的变化。结果表明:拉伸温度对纤维稳定拉伸影响较大,最佳温度为105~115℃;且初生纤维的纤度越小,高倍拉伸纤维强度越大,随拉伸倍数的提高,纤维的强度和声速取向都显著提高并改善了纤维的热性能和力学性能,但断裂伸长却呈下降趋势。 相似文献
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The present work studied the preparation of nanocomposites of polyamide-6 (PA6) containing nanofibrillated cellulose by melt blending in a twin screw extruder at different screw rotations to verify the fibrillation of cellulose fibers. Initially, the jute fibers were purified, hydrolyzed, and modified with titanium isopropoxide and aminopropyl silane, as well as with the two chemical modifications. They were incorporated into the polymeric matrix aiming that the shear in processing further aids in fiber fibrillation. The scanning electron microscopy analysis images of the composites showed the presence of fibers with nanodiameters dispersed in the PA6 matrix. The doubly modified fibers resulted in more fibrillation during extrusion. Increasing the screw speed of the extruder improved the degree of crystallinity for the composites with the modified fibers. The thermogravimetric measurements showed that the composite containing the doubly modified fibers increased the maximum degradation temperature. The storage modulus increased for the composites with the insertion of the treated fibers, and the glass transition temperature decreased in some composites. The composites showed higher pseudoplastic behavior, especially at high shear rates. 相似文献
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Microwave heating of polymers: Influence of carbon nanotubes dispersion on the microwave susceptor effectiveness 下载免费PDF全文
Begoña Galindo Adolfo Benedito Fernando Ramos Enrique Gimenez 《Polymer Engineering and Science》2016,56(12):1321-1329
Carbon nanotubes dispersion within the polymer matrix is a very important factor to take into account when developing new nanocomposites with optimized properties. In this article, dispersion studies have been carried out with polypropylene filled with 1% of multiwall carbon nanotubes. The nanocomposites were obtained by melt compounding in a corotative twin screw extruder. Processing parameters as screw speed, screw configuration and feeding technology were modified to analyse their effect onto carbon nanotubes dispersion. Developed nanocomposites were exposed to microwave heating (5.8 GHz, 700 W, 60 min) and heating temperature was monitored. The relation between dispersion level of carbon nanotubes and heating effectiveness was studied. Microwave heating efficiency of carbon nanotubes was increased as dispersion was improved. Electrical conductivity of nanocomposites was measured and used as indirect variable of microwave heating susceptor of carbon nanotubes nanocomposites. Higher electrical conductivity indicates a better microwave susceptor propertiy of the nanocomposite. POLYM. ENG. SCI., 56:1321–1329, 2016. © 2016 Society of Plastics Engineers 相似文献
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铝塑复合管硅烷交联聚乙烯专用料的研究 总被引:2,自引:0,他引:2
研究了高密度聚乙烯(HDPE)/线性低密度聚乙烯(LLDPE)硅烷接枝交联体系。分析了过氧化二异丙苯(DCP),乙烯基三乙氧基硅烷(VTES),加工设备及工艺条件(温度,螺杆转速)对体系熔体流动速率(MFR)和凝胶含量的影响。并用Buss混炼设备制备出高流动性的铝塑复合管硅烷接枝交联PE专用料。 相似文献
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采用动态硫化法,在双螺杆挤出机中制备以聚丙烯(PP)/三元乙丙橡胶(EPDM)为基体材料的热塑性弹性体,研究螺杆转速对PP/EPDM热塑性弹性体相态结构及性能的影响;采用差示扫描量热(DSC)仪分析了PP/EPDM热塑性弹性体的结晶性能,通过扫描电子显微镜(SEM)分析PP/EPDM热塑性弹性体的微观相态结构,并用万能试验机等对其力学性能进行测试。结果表明,随着螺杆转速的增加,PP/EPDM热塑性弹性体的结晶温度降低,凝胶含量、拉伸强度和断裂伸长率先增大后减小,压缩永久变形先减小后增大,而螺杆转速对硬度的影响不明显。当螺杆转速为180 r/min时,PP/EPDM热塑性弹性体的凝胶含量、拉伸强度和断裂伸长率均达到最大值,分别为56.8%,15.9 MPa和634%,压缩永久变形和硬度(邵A)均达到最小值,分别为68.8%,88。 相似文献
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短碳纤维增强聚丙烯复合材料性能的研究 总被引:1,自引:0,他引:1
本文研究了单螺杆挤出机加工短碳纤维增强聚丙烯复合材料(CFRPP)的性能。结果表明,经表面处理的短碳纤维与PP复合,得到的材料其拉伸强度、冲击强度和热变形温度有明显提高,成型收缩率显著减小、电性能与半导体相近。本文还结合拉伸断面的电镜照片,比较分析了表面处理前后短碳纤维增强PP复合材料力学性能的变化。 相似文献