Papers by Author: Chung Hao Wang

Abstract: Carbon nanotubes (CNTs) were functionalized using a simple method of heat treatment under oxygen atmosphere followed by an immersion in a tin nitrate aqueous solution. And well-dispersed SnOx nanodots were decorated on the surface of CNTs. X-ray photoelectron spectroscopy (XPS) analysis showed that the O/C ratio increases with oxygen-treated time. The distribution of carbon-containing functional groups on the CNTs surface, i.e., C−C, C−O, C=O, O−C=O, and π−π* shake up bonds can be identified and deconvoluted by a symmetrical Gauss function. The contact angle of H2O and CNTs is dependent on O/C ration. The relationships between the fraction of carbon-containing functional groups and various oxygen treatment times are also discussed.

Abstract: The functionalized multiwall carbon nanotubes (MWNTs) have been prepared by free radical reaction with maleic acid and maleic anhydride. The functionalized MWNT was further blended with poly(dimethylsiloxane) (PDMS) based Poly(urea-urethane) (PUU). Both maleic acid modified MWNT (Maa-g-MWNT) and maleic anhydride modified MWNT (Mah-g-MWNT) showed enhanced dispersion compared with that of pristine MWNT and PUU.For MWNT/PUU nanocomposites containing 5 phr functionalized MWNT, the maximum microwave absorption was -19.2 dB for Maa-g-MWNT/PUU nanocomposites and was -22 dB for Mah-g-MWNT/PUU nanocomposites.