基于不同构型转子制备碳材料填充聚偏氟乙烯复合材料的研究

发布时间：2018-02-02 23:32

本文关键词： 聚偏氟乙烯碳纤维碳纳米管密炼机转子数值模拟　出处：《华东理工大学》2015年硕士论文　论文类型：学位论文

【摘要】：转子构型是影响混炼设备混炼特性的重要因素。本文针对一维碳材料(碳纤维、碳纳米管)填充聚合物的制备,以提高填充改性复合材料性能为目标,探讨密炼机转子结构和工艺条件对混合材料性能的影响。利用POLYFLOW软件对密炼机叠片式转子和螺旋角分别为67.5°和40°的新型高拉伸腰鼓形转子的混炼流场特性与混炼过程进行了模拟；并对其压力、剪切速率的分布特点进行了讨论,对流场的解聚能力和分布混合能力及其影响因素进行了分析。在此基础上,采用上述3种转子分别制备碳纤维、碳纳米管填充聚偏氟乙烯复合材料,并对所获得的复合材料的导电、导热特性和机械性能进行了表征,探讨了流场特性对共混物微观相畴特性、物理特性、机械性能的影响。研究得出以下结论：(1)叠片式转子具有较强的剪切作用,有利于分散混合；而腰鼓形转子混炼流场中拉伸流所占比例较高,有利于分布混合。叠片式转子分散混合能力最强,螺旋角为40°的腰鼓形转子分布混合能力最强。(2)腰鼓形转子混炼流场中较弱的剪切作用可以保留复合材料中较长的碳纤维残存长度,其较强的分布混合能力有利于碳纤维在复合材料中均匀分布；采用螺旋角为40°的腰鼓形转子制备的复合材料中碳纤维残存平均长度为435μm,较采用叠片式转子长257μm,拉伸强度高15MPa。(3)碳纳米管改性复合材料制备实验表明较高的剪切作用有利于碳纳米管在聚偏氟乙烯中的分散。采用叠片式转子制得的复合材料中碳纳米管分散效果最好,体系形成渗流网络,复合材料体积电阻率为106Ω-cm；而采用腰鼓形转子制备的复合材料中碳纳米管团聚较明显,体积电阻率为1014Ω·cm。
[Abstract]:Rotor configuration is an important factor affecting the mixing characteristics of mixing equipment. In this paper, the preparation of one-dimensional carbon materials (carbon fiber, carbon nanotubes) filled polymer, with the aim of improving the properties of filled modified composites. The effects of rotor structure and process conditions on the properties of mixing materials were discussed. The laminated rotor and the new type of high tensile waist drum with spiral angles of 67.5 掳and 40 掳were analyzed by POLYFLOW software. The mixing flow field characteristics and mixing process of the rotor are simulated. The distribution characteristics of pressure and shear rate were discussed, and the depolymerization ability, distribution and mixing ability of the flow field and its influencing factors were analyzed. On the basis of this, carbon fibers were prepared by the three kinds of rotors mentioned above. Carbon nanotubes were filled with polyvinylidene fluoride (PVDF) composites. The conductivity, thermal conductivity and mechanical properties of the composites were characterized. The effects of flow field characteristics on the microscopic phase domain and physical properties of the blends were discussed. The following conclusions are drawn: the laminated rotor has strong shear effect, which is favorable for dispersion and mixing. But the ratio of tensile flow in the mixing flow field of waist drum rotor is higher, which is favorable to distribution and mixing. The laminated rotor has the strongest dispersion and mixing ability. When the helical angle is 40 掳, the mixing ability of the waist drum rotor is the strongest. (2) the weak shear action in the mixing flow field of the waist drum rotor can retain the longer carbon fiber residual length in the composite material. Its strong distribution and mixing ability is beneficial to the uniform distribution of carbon fiber in the composites. The average residual length of carbon fiber is 435 渭 m, which is 257 渭 m longer than that of laminated rotor. High tensile strength 15MPa.f3). The experimental results of carbon nanotube modified composites show that higher shear action is beneficial to the dispersion of carbon nanotubes in polyvinylidene fluoride (PVDF), and the carbon nanotubes (CNTs) have the best dispersion effect in the composites prepared by laminated rotor. The percolation network was formed, and the volume resistivity of the composite was 106 惟 -cm. However, the carbon nanotube agglomeration was obvious in the composites prepared with a waist drum rotor, with a volume resistivity of 1014 惟路cm ~ (-1).
【学位授予单位】：华东理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TQ342.742;TB33

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