Effects of the Mould Temperature on the Properties of Graphite/Carbon Fiber/Copper/Phenolic Resin Composites

2013 ◽  
Vol 470 ◽  
pp. 31-34
Author(s):  
Mi Dan Li ◽  
Yao Lu ◽  
Xin Guo

Natural graphite, carbon fiber and copper powder as fillers are incorporated into phenolic resin to fabricate conductive polymer composites by hot compression moulding. The effects of the preparing method and mould temperature on the density, electrical conductivity and hardness of composites are investigated. It is found that the density, electrical conductivity and hardness of composites increase as mould temperature increase from 150 °C to 180 °C. Up to 200 °C, the hardness of composite shows a large decrease. At 170 °C, the density, electrical conductivity and hardness of composites are 1.904 g/cm3, 3.43 × 103S/m and 54 HS, respectively. Oxidation action occurring in the phenolic resin could be the main reason for the large decrease of hardness as temperature increases up to 200 °C.

2013 ◽  
Vol 483 ◽  
pp. 115-118
Author(s):  
Mi Dan Li ◽  
Huan Niu ◽  
Hong Yang

The polymer composites consist of phenolic resin, natural graphite, carbon fiber and copper powder, are fabricated by hot compression moulding or compression moulding followed by post-curing. The density, electrical conductivity and flexural strength of composites are analyzed to determine the influences of post-curing temperature and preparing method on the physical, electrical and mechanical properties of composites. It is found that the density, electrical conductivity and flexural strength of composites increase with increasing post-curing temperature for composites prepared by compression moulding followed by post-curing. The flexural strength is more strongly dependent on post-curing temperature. At 170 °C, the density, electrical conductivity and flexural strength of composites were 1.85 g/cm3, 2.94 × 103S/m and 40 MPa respectively. The cross-linking skeleton structure well established in the composites could be the main reason for the largely increasing of flexural strength as post-curing temperature increases. The results also show that the properties of composites prepared by hot compression moulding are higher than those of composites prepared by compression moulding followed by post-curing.


2013 ◽  
Vol 706-708 ◽  
pp. 95-98
Author(s):  
Mi Dan Li ◽  
Dong Mei Liu ◽  
Lu Lu Feng ◽  
Huan Niu ◽  
Yao Lu

Polymer matrix composites made from phenolic resin are filled with natural graphite powders. They are fabricated by compression molding technique. The density, electrical conductivity and flexural strength of composite are analyzed to determine the influences of mould pressure and mould pressing time on the physical, electrical and mechanical properties of composite. It is found that the density, electrical conductivity and flexural strength of composites increased with increasing mould pressure. Under pressure of 40 MPa for 60 min, the density, electrical conductivity and flexural strength of composites were 1.85 g/cm3, 4.35  103 S/cm and 70 MPa, respectively. The decreased gaps could be the main reason for the increasing of density, electrical conductivity and flexural strength as mould pressure increases. The results also show that the density of composites increased with increasing mould pressing time.


2012 ◽  
Vol 729 ◽  
pp. 260-265
Author(s):  
M. Olah ◽  
Ferenc Ronkay

Investigation of conductive polymer composites have been carried out using polypropylene (PP) and polyphenylene sulfonate (PPS) for matrix compound and graphite, carbon black and multi walled carbon nanotubes (MWCNT) for fillers. The comparison of these matrix materials with respect to the resulting electrical conductivity were investigated in depth. The effect of quantity of nanotubes and their dispersion on electrical conductivity and formability was also investigated. It has been found that PPS composites show much higher conductivity, however the high temperature needed for forming, and high viscosity in case of high filler content (50 wt% <) make the processing difficult, therefore the injection molding of the resulting material is currently not possible. Furthermore in contradiction to the literature the addition of MWCNT did not raise the conductivity significantly, therefore the focus have been kept on filler content instead.


2008 ◽  
Vol 109 (1) ◽  
pp. 577-583
Author(s):  
Wei Li ◽  
Zhenhua Chen ◽  
Jin Li ◽  
Xianhong Chen

Author(s):  
Xiaolong Gao ◽  
Yao Huang ◽  
Xiaoxiang He ◽  
Xiaojing Fan ◽  
Ying Liu ◽  
...  

Electrically conductive polymer composites are in high demand for modern technologies, however, the intrinsic brittleness of conducting conjugated polymers and the moderate electrical conductivity of engineering polymer/carbon composites have highly constrained their applications. In this work, super high electrical conductive polymer composites were produced by a novel hot embossing design. The polydimethylsiloxane (PDMS) composites containing short carbon fiber (SCF) exhibited an electrical percolation threshold at 0.45 wt%, and reached a saturated electrical conductivity of 49 S/m at 8 wt% of SCF. When reduced the sample thickness from 1.0 mm to 0.1 mm by the hot embossing process, a compression-induced percolation threshold occurred at 0.3 wt%, while the electrical conductivity was further enhanced to 378 S/m at 8 wt% SCF. Furthermore, the additional of a second nanofiller of 1 wt%, such as carbon nanotube or conducting carbon black further increased the electrical conductivity of the PDMS/SCF (8 wt%) composites to 909 S/m and 657 S/m, respectively. The synergy of the densified conducting filler network by the mechanical compression and the hierarchical micro-/nanoscale filler approach has realize super high electrical conductive yet mechanical flexible polymer composites for modern flexible electronics applications.


2014 ◽  
Vol 577 ◽  
pp. 39-43
Author(s):  
Yue Xian Zhang ◽  
Bin Li

Vulcanization methods of conductive silicon rubber are described in this paper. Several common vulcanization agents are also be introduced. The conductivity and mechanical properties of the conductive silicon rubber composite materials are effected by vulcanization systems. The influence degree is introduced by respectively using different vulcanization method, vulcanizing time and vulcanizing temperature. The research progress of vulcanization system of conductive polymer composites is elaborated.


Sign in / Sign up

Export Citation Format

Share Document