• Applied Chemistry for Engineering
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• v.23 no.3
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• pp.313-319
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• 2012

In this work, the electroplating of copper was introduced on PAN-based carbon fibers for the enhancement of mechanical interfacial strength of carbon fibers-reinforced composites. The surface properties of carbon fibers were determined by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and contact angle measurements. Its mechanical interfacial properties of the composites were studied by interlaminar shear strength (ILSS) and critical stress intensity factor ($K_{IC}$). From the results, it was found that the mechanical interfacial properties of Cu-plated carbon fibers-reinforced composites (Cu-CFRPs) enhanced with increasing the Cu plating time, Cu content and COOH group up to Cu-CFRP-30. However, the mechanical interfacial properties of the Cu-CFRPs decreased dramatically in the excessively Cu-plated CFRPs sample. In conclusion, the presence of Cu particles on carbon fiber surfaces can be a key factor to determine the mechanical interfacial properties of the Cu-CFRPs, but the excessive Cu content can lead the failure due to the interfacial separation between fibers and matrices in this system.

• Applied Chemistry for Engineering
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• v.16 no.2
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• pp.257-261
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• 2005

The microbial cellulose is in a form of three dimensional net structures that consists of 20~50 nm fibrils. It possesses high crystallinity and orientation. It is difficult to synthesize large amount of fibrous carbon nanomaterials by the carbonization process using raw materials such as polyacrylonitrile (PAN), regenerated cellulose (Rayon) and pitch. However, it seems possible thru the application of microbial cellulose as raw material. The application of such cellulose can be further extended to the synthesis of highly oriented graphite fiber. Out of three different cellulose-producing strains, G. xylinus ATCC11142 was chosen as it has the highest productivity (0.066 g dried cellulose/15 mL medium). Tar is often produced during the carbonization of cellulose that limits the formation fibrous structure of the carbonized sample. In order to solve such a problem, pre-studied purification methods of carbon nanotube such as liquid phase oxidation, gas phase oxidation and filtration associated with ultrasonication were applied at the carbonized cellulose. In that case. only by filtration associated with ultrasonication, improved the formation of fiber structure of the carbonized cellulose.