Fabricaton of PEMFC separators with conducting polymer composites by injection molding process and evaluation of moldability and electrical conductivity of the separators

Authors investigated the relationship among processing parameters, microstructures, electrical conductivity and mechanical property of injection molded nanoparticle filled polymer composites at present study. Standard tensile specimens were injected under different injecting pressures and packing pressures. The molded specimens were removing five layers from the surface to observe the microstructures at different positions of the moldings. The electrical properties were measured with a two-terminal standard resistor under DC condition at room temperature, and the mechanical properties of the moldings were measured by INSTRON 5580 Universal testing machine. The results showed that filled nanoparticles may form the best conductive path under the higher packing pressure matched with higher injection pressure. The mechanical properties of the molding depend on not only the concentration of the nanofiller, but processing conditions as well.

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Electrical Conductivity of Conducting Polymer Composites based on Conducting Polymer/Natural Cellulose

ELKHA ◽

10.26418/elkha.v13i1.46048 ◽

2021 ◽

Vol 13 (1) ◽

pp. 84

Author(s):

Berlian Sitorus ◽

Mariana B Malino

Keyword(s):

Electrical Conductivity ◽

Polymer Composites ◽

Conducting Polymer ◽

Electrochemical Impedance ◽

Peat Soil ◽

Experimental Studies ◽

Hybrid Architecture ◽

System Method ◽

Natural Cellulose ◽

Conducting Polymer Composites

– Merging each of the best properties of components into a composite design or hybrid architecture opens up opportunities to develop electroconductive materials as conducting polymer composite. This work deals with studying the electrical conductivity of conducting polymer composites made of cellulose extracted from two biomass: empty fruit bunch from oil palm and peat soil. Two kinds of conducting polymers have been used to fabricate the composites, i.e. polyaniline and polypyrrole, which are polymerized from their monomers, aniline and pyrrole. The novelty of this research is the using of biomass as the source of cellulose to produced conducting polymer composites by adding conducting polymer as filler into polymer matrix. We report experimental studies about the influence of monomer addition on the electrical conductivity of composites produced. The conductivity of the material was measured by using the Electrochemical Impedance System method. The experiments were carried out as a four-set experiment, using two different cellulose sources, EFB and peat soil, combined with aniline and pyrrole. The mass ratio variations of the monomer: cellulose are 1, 2, 3, and 4. The conductivities of the composites increased when more aniline or pyrrole was blended with the extracted cellulose from each source, either EFB or peat soil. The conductivity of composite PANI/EFB, which is 3.5 ´10-3 - 1.1´10-2 S/cm, is in the semiconductor range that makes the composites useful for many applications.

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The use of image analysis in evaluation of the fibers orientation in Wood-polymer composites (WPC)

Open Engineering ◽

10.1515/eng-2016-0099 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 2

Author(s):

Arkadiusz Bednarz ◽

Wiesław Frącz ◽

Grzegorz Janowski

Keyword(s):

Injection Molding ◽

Polymer Composites ◽

Fiber Orientation ◽

Point Of View ◽

Injection Molding Process ◽

Molding Process ◽

Mathematical Algorithm ◽

Wood Polymer ◽

Wood Polymer Composites ◽

Fibers Orientation

Abstract In this paper a novel way of a digital analysis of fibers orientation with a five-step algorithmwas presented. In the study, a molded piece with a dumbbell shape prepared from wood-polymer composite was used. The injection molding process was examined in experimental and numerical way. Based on the developed mathematical algorithm, a significant compliance of fiber orientation in different areas of the molded piece was obtained. The main aim of thisworkwas fiber orientation analysis of wood-polymer composites. An additional goal of thiswork was the comparison of the results reached in numerical analysis with results obtained from an experiment. The results of this research were important for the scientific and also from the practical point of view. In future works the prepared algorithm could be used to reach optimal parameters of the injection molding process.

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Preliminary Study on Injection Molding Process of Single Polymer Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.532-533.121 ◽

2012 ◽

Vol 532-533 ◽

pp. 121-125

Author(s):

Qian Chao Mao ◽

Jin Nan Chen ◽

Jian Wang

Keyword(s):

Flexural Strength ◽

Injection Molding ◽

Polymer Composites ◽

Injection Pressure ◽

Injection Molding Process ◽

Molding Process ◽

Microstructure Observation ◽

The Matrix ◽

Interfacial Compatibility ◽

Nozzle Temperature

An approach of preparing single polymer composites (SPCs) by injection molding was demonstrated. Polypropylene (PP) was used as a model system to investigate this method. The thermal properties of PP granules and PP fibers were analyzed by Differential Scanning Calorimeter (DSC) to determine the processing temperatures. The flexural test of PP SPCs showed that the flexural strength was obviously improved compared to the non-reinforced PP. The results also indicated that the injection pressure, holding pressure and nozzle temperature greatly affect the flexural strength of PP SPCs. The microstructure observation showed no gaps between fibers and the matrix by using Scanning Electron Microscopy (SEM). The matrix melt was able to penetrate into fiber webs and the two materials had good interfacial compatibility.

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Effect of Weld Line Defects on Electrical Conductivity of Injection Molded Parts with Carbon Nano Fibers/PP Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.233-235.1136 ◽

2011 ◽

Vol 233-235 ◽

pp. 1136-1140

Author(s):

Lei Xie ◽

Xiao Yong Tian ◽

Wang Qing Wu ◽

Di Chen Li ◽

Bing Yan Jiang ◽

...

Keyword(s):

Electrical Conductivity ◽

Injection Molding ◽

Conductive Polymer ◽

Weld Line ◽

Injection Molding Process ◽

Molding Process ◽

Molded Part ◽

Molded Parts ◽

Line Defects ◽

Injection Molded

As well known, the weld line defect in injection molding process results detrimental to mechanical properties and surface quality. However, the electrical conductivity of the injection molded part is influenced as well. In this study, in order to reveal the mechanism of the weld line affecting the electrical conductivity of injection molding parts, the conductive polymer composites with various carbon nanofibers filling contents were compounded. Those composites were formed as the tensile samples with and without weld line defects by injection molding process. According to the electrical resistance measurements for the samples, it can be found that at relative low filling content of 10wt%, the weld line contributes to increase the electrical conductivity of the injection molding parts due to its effect on nanofibers’ orientation. However, when the filling content is higher than 20wt%, this effect is not significant any more.

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