填充聚合物的流变行为的探讨

对填充聚合物体系:炭黑填充聚合物,无机物质填充聚合物,纤维填充聚合物的流变行为分别进行了讨论。初步探讨了影响填充聚合物流变性能的因素,并对其流变特性和粘弹性质作了简要概括。     

填充聚合物的流变行为探讨

对炭黑、无机物质、纤维填充聚合物的流变行为分别进行了讨论。初步探讨了影响填充聚合物流变性能的因素,并概括了其流变特性和粘弹性质。     

无机粒子填充聚合物的流变行为

研究了无机粒子填充聚合物的流变行为，探讨了无机粒子体积分数、无机粒子和聚合物组分特性、无机粒子与聚合物的界面特性和相互作用、以及加工条件对无机粒子填充聚合物的流变行为的影响。研究表明，一般情况下无机粒子填充聚合物的黏度随着填充聚合物体积分数的增加而增大；粒子性质、聚合物组分特性都会对流变性能产生影响，目前只能通过实验进行优选；无机纳米粒子填充聚合物有不同于普通粒子填充的反常现象，如果纳米粒子体积分数控制在一定范围内，填充聚合物的黏度可能出现随填充粒子体积分数增大而下降的趋势；表面活性剂、偶联剂等可以使无机粒子填充聚合物的流动性能得到显著改善；高速混合、增大剪切速率及升高温度都可以使无机粒子填充聚合物有更好的流变性能。     

高填充性聚合物/纳米粒子复合材料的流变行为研究进展

介绍了纳米粒子的含量、尺寸、形状、表面处理、分散性和聚合物熔体等对聚合物/纳米粒子复合材料流变行为的影响,概述了近些年来高填充性聚合物/纳米粒子复合材料的流变行为的研究进展,并对高填充性聚合物/纳米粒子复合材料的黏弹机理进行了总结。     

聚乙烯改性材料流变行为研究进展

对无机粒子、弹性体和其他类型的聚合物填充改性聚乙烯的流变行为分别进行了讨论，探讨了影响各个体系的流变性能的因素及产生这种流变行为的机理，并总结了改性体系的流变行为的较典型的一些规律。     

粘土或纳米碳酸钙填充聚合物的结晶性能和流变行为研究

总结了粘土、纳米碳酸钙填充聚合物的结晶性能和流变行为，阐述了无机纳米填料对聚合物复合材料结晶性能和流变行为的影响，同时论述了结晶性能和流变行为与纳米复合材料力学性能及加工性能的关系。结果表明，粘土和纳米碳酸钙对结晶聚合物均有异相成核剂的作用，在基本保持聚合物强度的同时，明显改善复合材料的韧性，同时保持材料原有的加工性能。     

振动力场作用下聚合物熔体本构关系的研究进展

从加工和理论两方面总结和评述了振动力场作用下聚合物熔体本构关系的研究成果,着重介绍了高分子链缠结动力学的结构网络本构理论。同时指出经典的连续介质本构方程不能精确描述振动力场作用下的聚合物熔体流变行为,而分子链缠结动力学瞬态网络理论可以精确描述大振幅振动剪切场下的聚合物流变行为。     

高分子聚合物在洗涤剂中的应用

从高分子聚合物的特点出发 ,综述了不同分子结构、不同分子量的高分子聚合物在洗涤剂中各个方面的应用。这些应用方面包括 :高分子表面活性剂 ;高分子对洗涤剂在制造和使用中的流变行为改性 ;高分子在洗涤过程中的抗再沉积作用、防色转移作用和对织物纤维的抗污处理作用(又称污垢释放剂作用)。最后 ,就高分子在洗涤剂中应用研究的现状及趋势作了简要概述。     

PET/蒙脱土纳米复合材料的流变性能

采用毛细管流变仪的方法，研究具有反应活性的有机蒙脱土与聚对苯二甲酸乙二酯通过原位聚合和熔融共混所得的2种插层复合材料的流变行为。结果表明，2种插层方法制备的纳米复合材料在熔融流变性能方面具有较大的差异，熔融共泥时更表现出无机填充聚合物体系的普通特征。熔融插层复合材料在低浓度复合时会出现高浓度大颗粒粒子填充聚合物体系类固体行为的屈服现象。     

炭黑在EVA中的导电性研究

以EVA为高分子聚合物,采用不同级别的导电炭黑,研究了导电炭黑填充高分子聚合物的导电性,讨论了不同级别和不同用量的导电炭黑在聚合物中的分散性,以及对高分子聚合物导电性的影响。实验结果表明,导电炭黑高分子聚合物的导电性主要取决于不同级别的导电炭黑的表面积和结构等特性、炭黑的不同用量以及导电炭黑的聚集体在高分子聚合物的分散程度。     

Rheological behavior of polymer melts with natural fibers

Flow behavior of polymer liquids filled with short fibers (particulate fillers) was theoretically analyzed from the point of view of the free volume theory. Assuming that the filler addition changes the occupied volume, while the temperature variations cause mainly the free volume changes, a general expression describing the viscosity of the system as a function of the filter content, temperature variations, and rheological properties of the pure polymer liquid was derived. If the viscosity curve of the unfilled polymer is described by the Carreau equation, the corresponding viscosity curve of the filled polymer is also represented by an equation of Carreau type. However, this equation has other values of Newtonian viscosity and the power exponent in comparison with the initial equation. Both parameters depend on the filler content and temperature. The derived equation predicts a viscosity rise and a stronger non‐Newtonian behavior of the system with increasing filler content. The temperature rise exerts an opposite effect on the rheological behavior. The theoretical predictions are in good accordance with viscosity measurements for low‐density polyethylene and polystyrene melts filled with short cotton, flax, and hemp fibers. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1401–1409, 2005     

Study of the Role of Silane-treated Filler on the Compatibility of Polypropylene/Polystyrene Blends at Different Ratios

A systematic study of the effect of the filler on the immiscible blend properties is presented as a function of the blend composition. As a representative of semicrystalline polymer/amorphous polymer blends, a polypropylene/polystyrene system was chosen. The presence of filler in the blends has induced significant changes in the rheological properties. This behavior is a function not only of filler surface treatment but also of blend composition. Solid state dynamic mechanical analysis is performed and the relaxation behavior is correlated with the morphology of the blends. The increase in tensile strength of the blends filled with surface-treated glass beads is related to the enhancement of the adhesion and polymer/polymer interactions.     

填充型导电高分子复合材料的逾渗理论进展

总结了粒子填充型导电体系逾渗网络的形成及逾渗理论概况，以热力学和动力学的观点对导电粒子种类、形状、浓度、分布和分散、基体树脂的种类、粒子与基体树脂的相互作用、加工条件等影响逾渗的重要因素作了系统的分析，阐明了体系的导电性、微观形貌、流变性能和物理性能的相互关系。对低逾渗值填充聚合物尤其是炭黑复合材料的成型与加工提供了理论指导。     

玻璃微珠填充改性聚合物研究进展

玻璃微珠作为一种新型刚性粒子,除了对聚合物有增强增韧作用,在许多方面都已引起聚合物改性工作者的关注。本文从玻璃微珠对聚合物的增韧效果、玻璃微珠填充聚合物的界面、拉伸性能、动态力学性能、流变性能、压缩性能以及其他性能等方面综述了近年来玻璃微珠填充改性聚合物的最新研究进展。     

Rheological behavior of neat and carbon fiber-reinforced poly(ether ketone ketone) for extrusion deposition additive manufacturing

To develop new materials for extrusion additive manufacturing (AM) systems, a fundamental understanding of rheological properties is essential to correlate the effect of processing on material structure and its properties. In this work, the rheological properties of five different grades of neat and carbon fiber (CF)-reinforced poly(ether ketone ketone) are reported. Rheological properties are essential to understand the effect of reinforcing fibers and AM process parameters such as time, temperature, environment, and shear rate on flow behavior during processing. Small-amplitude oscillatory shear tests and steady shear tests indicated neat grades to exhibit less increase in viscosity over time when processed in air than the CF-filled grades. The filled grades showed greater shear thinning and lower sensitivity to temperature. Overall, this rheological analysis provides a broad framework for determining appropriate processing conditions for extrusion deposition AM of such high-temperature polymer systems.     

Effect of polymeric additives on the rheological properties of talc-filled polypropylene

The effect of small amounts of low molecular weight polypropylene oxide on the rheological properties of talc-filled polypropylene composites was studied experimentally using a capillary viscometer. The elastic behavior of the system was investigated by exit pressure and die swell methods. Initial studies showed that the talc filler does not influence the viscosity of the polypropylene but decreases the elasticity of the polymer system. Addition of oligomer concentration in a 40 wt percent talc-filled polypropylene not only decreases the viscosity but also further decreases considerably the elasticity of the filled polymer composite. In both cases about 3 wt percent oligomer cone entration appears to be optimal, and further addition of oligomer does not significantly influence the rheological characteristics of the talc-filled polypropylene composite.     

表面改性对聚丙烯/微米氢氧化镁复合材料性能的影响

研究了表面处理剂（钛酸酯和硅烷偶联剂）和原位聚合方法对聚丙烯/微米氢氧化镁（MH）复合材料的力学性能及流变性能的影响。采用DSC、SEM和毛细管流变仪对PP/MH（80/20）复合材料的性能进行了研究。结果表明：原位聚合改性后的微米MH与PP基体间的界面黏结力得到了加强,复合材料的冲击强度较填充未改性MH的复合材料提高了26.4 ％。在PP基体中添加聚合物包覆改性微米MH粒子的复合材料熔体流动速率较纯PP上升了64 ％。在相同剪切速率下,填充聚合物包覆改性MH的复合材料熔体表观黏度明显低于填充未改性微米MH的复合材料,表明聚合物包覆改性后的MH降低了其对PP熔体流动的阻碍作用,改善了PP/MH复合材料的流动性能。     

Rheograms of filled polymer melts from melt-flow index

Polymers filled with extending fillers, such as calcium carbonate or talc, or with reinforcing fillers, such as glass fibers or mica, are increasingly being used in a number of applications. The addition of fillers to a polymer changes the melt rheological behavior of the polymer. A knowledge of the viscosity vs. shear-rate flow curves of the filled system at various temperatures and as a function of filler parameters (such as filler type, shape, and amount) is necessary for process design, optimization, and trouble shooting. The generation of such rheological data is ezpensive and cumbersome in view of the broad range of fillers and the large numbers of filler parameters. In the present article, a unifying approach is proposed that coalesces the flow curves of filled systems of a polymer at various temperatures into a master curve that is independent of the filler parameters. An effective methods is presented to estimate the rheograms of filled systems with the use of a master curve, characteristic of a genetic resin type, knowing the melt-flow index and glass-transition temperature of the system. Master curves have been reported for filled system of low-density polyethylene, high-density polyethylene, poly-propylene polystyrene, nylons, poly(ethylene terephthalate), and polycarbonate.