Progress on the morphological control of conductive network in conductive polymer composites and the use as electroactive multifunctional materials

Experimental and modeling analysis of mechanical-electrical behaviors of polypropylene composites filled with graphite and MWCNT fillers

Conductive polymer composites (CPCs) have attracted intensive attention for several decades because they can endow the materials with not only good processability but also various functionalities e...

Advances in Responsively Conductive Polymer Composites and Sensing Applications

Enhanced electrical conductivity, mechanical modulus, and thermal stability of immiscible polylactide/polypropylene blends by the selective localization of multi-walled carbon nanotubes

Optimization of Mechanical Properties of Glass-Spheres-Filled Polypropylene Composites for Extrusion-Based Additive Manufacturing

The effect of maleic anhydride grafted polypropylene (MA-g-PP) compatibilizer on the mechanical and electrical properties of a polypropylene-carbon nanotube composite is presented. Commercially available grades of polypropylene homopolymer (PP) and multiwalled CNT (MCNT) were used to prepare composites (PP/MCNT) by melt compounding. The effects of maleic anhydride graft level and loading on material properties were investigated. The addition of MCNT without compatibilizer enhanced the mechanical properties of PP, whereas addition of both grades of MA-g-PP alone had a detrimental effect. When MA-g-PP was added as a compatiblizer to the PP/MCNT composite, flexural and tensile moduli increased, indicating that enhanced levels of MCNT dispersion within PP had been achieved. Strength of the nanocomposite decreased with the addition of both grades of MA-g-PP, possibly due to the deterioration of the mechanical properties of the polymer in the presence of lower molecular weight MA-g-PP. Electrical resistivity improved with both grades of MA-g-PP, with higher maleic anhydride graft levels having the most significant effect. Scanning electron microscopy analysis confirmed that the optimum state of dispersion was for the nanocomposite prepared with MA-g-PP with highest grafting level. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers

Effect of maleic anhydride grafted polypropylene compatibilizer on the morphology and properties of polypropylene/multiwalled carbon nanotube composite

The effect of maleic anhydride compatibilser on the mechanical, rheological and thermal properties of polypropylene–carbon nanotube composites is reported. A commercial grade of polypropylene copolymer was melt compounded with acid purified multiwalled carbon nanotubes at loadings up to 12 wt-%, with and without the addition of a maleic anhydride grafted polypropylene. Tensile and flexural moduli were found to increase with filler content at all nanotube loadings and these properties were enhanced by addition of maleic anhydride. Ultimate tensile strength increased with nanotube loadings up to 8 wt-% and then decreased; maleic anhydride had a negative effect on tensile strength most likely resulting from nanotube agglomerations. Rheological and morphological characterisations confirmed that dispersion was relatively poor in both systems suggesting that maleic anhydride improved interfacial bonding without significantly improving dispersion, for the materials and compounding conditions examined in this work.

Influence of maleic anhydride compatibiliser on properties of polpropylene/multiwalled carbon nanotube composites

Abstract Polypropylene (PP) reinforced with 2 and 4 wt% of multi-walled carbon nanotubes (MWNT) were melt-blended in twin screw extruder and then molded by compression or micromolding process. The impact of injection speed on the surface morphology, rheological and tensile characteristics was investigated by using a scanning electron microscope, parallel plate rheometry, and tensiometry. Results showed that the tensile properties of micro-molded specimens were remarkably higher than those of the compression molded sheets. Compared to compression molded sheets, micromolded specimens demonstrated up to 40 and 244% higher tensile stiffness and yield strength, respectively, most likely due to the alignment of polymer chain segments in the flow direction induced during the micromolding process. It was observed that the fast filling speed caused a drop in the tensile properties of the nanocomposites and polymer. Rheological examination revealed that the presence of a rheological percolation network in the nanocomposites produced by micromolding and the fast injection speed was beneficial for establishing the percolated network. Morphological examination revealed that the size of nanotube agglomerations that appeared in micromolded specimens was up to five times smaller than in compression molded sheets and the agglomeration size decreased with the increase of the injection speed.

Tensile, rheological and morphological characterizations of multi-walled carbon nanotube/polypropylene composites prepared by microinjection and compression molding

G. S. Ezat

Papers

Effect of maleic anhydride grafted polypropylene compatibilizer on the morphology and properties of polypropylene/multiwalled carbon nanotube composite

Influence of maleic anhydride compatibiliser on properties of polpropylene/multiwalled carbon nanotube composites

Tensile, rheological and morphological characterizations of multi-walled carbon nanotube/polypropylene composites prepared by microinjection and compression molding

Tensile and rheological characterizations of biaxially stretched polypropylene/multi-walled carbon nanotube composite

Effect of extrusion cycles on the dispersion and properties of polypropylene/multi-walled carbon nanotube composite