Table of Contents
Journal of Nanoscience
Volume 2016, Article ID 7258313, 6 pages
Research Article

The Role of Ammonia in Synthesis of Silver Nanoparticles in Skim Natural Rubber Latex

Department of Chemical Engineering, Faculty of Engineering, Thammasat University, Pathumthani 12120, Thailand

Received 9 March 2016; Accepted 10 April 2016

Academic Editor: Kalimuthu Kalishwaralal

Copyright © 2016 Panu Danwanichakul et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Silver nanoparticles (AgNPs) were synthesized in skim natural rubber latex, the by-product from concentrated latex production. The role of ammonia was investigated by varying the concentration to be 0.217, 0.362, 0.377, 0.392, and 0.406 wt%. The emergence of AgNPs was detected by UV-visible spectrophotometer and electrical conductivity meter. Upon increasing ammonia concentration, the ABS peak increased to a maximum and slightly shifted to a higher wavelength and then it decreased afterward and slightly shifted to a lower wavelength. The shift of the ABS peak was consistent with the conductivity result. The kinetic model was proposed to explain the competition between the reducing effect and size-controlling effect of ammonia. The reducing effect seemed to dominate in the low range of concentration while the size-controlling effect via the formation of complex ion was important in the higher range. The TEM figures evidently confirmed the effects.