Natural antioxidants for radiation vulcanization of natural rubber latex

The anti-oxidant properties of some non-water soluble amino acids were tested on radiation vulcanized natural rubber latex (RVNRL). Among these were cystine, tyrosine, asparagine phenyl alanine and alanine. The results indicate that all of these amino acids have anti-oxidant properties with cystine, alanine and asparagine, phenyl alanine exhibiting higher anti-aging properties on RVNRL. Combinations of these amino acids improved the antioxidant properties in RVNRL. Keratin from chicken feathers was also tested for its antioxidant properties in RVNRL. Different methods of extraction of keratin gave different aging effects on RVNRL. Reduction of keratin with sodium bisulfite initiated antioxidant activity in RVNRL. Extraction of keratin with alkaline solution however caused pro-oxidant properties in RVNRL. (C) 2002 Elsevier Science Ltd. All rights reserved.