Yadav R R, Mishra Giridhar, Yadawa P K, Kor S K, Gupta A K, Raj Baldev, Jayakumar T
Physics Department, University of Allahabad, Allahabad 211002, India.
Ultrasonics. 2008 Nov;48(6-7):591-3. doi: 10.1016/j.ultras.2008.06.008. Epub 2008 Jun 19.
A polymer colloidal solution having dispersed nanoparticles of Cu and Au metals have been developed using a novel chemical method. Average size of the nanoparticles could be varied in the 4-10 nm range by conducting the reaction at an elevated temperature of 50-70 degrees C. Colloidal solutions of representative concentrations of 0.1-2.0 wt% Cu/Au contents in the primary solutions are used to study the modified ultrasonic attenuation and ultrasonic velocity in PVA polymer molecules on incorporating the Cu/Au particles. A characteristic behaviour of the ultrasonic velocity and the attenuation are observed at the particular temperature/particle concentration. The results demonstrate that the primary reaction during the nanoparticles-PVA colloidal formation occurs in divided groups in small micelles. The results are analyzed predicting the enhanced thermal conductivity of the samples.
