Treatment of rubber latex
AssigneeThe Board of the Rubber Research Institute of Malaysia
InventorGeoffrey Thomas Knight
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Abstract
Natural rubber latex is treated with a para-nitrosoaniline in the presence of a metal dialkyldithiocarbamate in order to protect the rubber from oxidative degradation. A hydroxylamine salt is added to the rubber latex before, during or after the reaction to reduce coloration of the latex on storage.
Claims12
In a method of treating preserved natural rubber latex which method comprises reacting rubber in the latex with a p-nitrosoaniline in the presence of a metal dialkyldithiocarbamate, the improvement which consists of including in the rubber latex, before, during or after the reaction, but before any significant coloration of the rubber latex has taken place, a hydroxylamine salt in an amount of from 0.05 to 0.5 parts by weight per 100 parts of rubber to reduce coloration of the latex on storage.
A treated natural rubber latex having the following properties:
- a. a half-filled barrel of the latex is stable to storage in air under ambient conditions for 5 days without substantial colouration;
- b. the tensile strength of a vulcanized latex article made from the rubber latex remains at at least 60% of its original value during treatment with carbon tetrachloride and aging for 3 days at 100.degree. C in air.
Dependencies are inferred from the claim text.