PROTEIN LEVELS AFFECT THE CURE EFFICIENCY AND ALLERGENIC POTENTIAL OF POLYISOPRENE LATICES

摘要

Commercial NR latex has a higher total protein content than guayule (GR) latex. Some NR proteins are allergens bound to the rubber particle surface. Washing NR latex with a non-ionic surfactant displaced these particle-bound proteins and reduced allergens by more than 95%. The cost of such deproteination was reduced vulcanization efficiency, as determined by crosslink density. The extent of vulcanization correlated well with both total protein and allergen levels. Compared with films prepared from untreated NR latex, films from both surfactant-treated NR latex and GR latex had lower states of cure. Where particle-bound proteins were still present, as they are in GR latex, crosslink development could be completed by heat aging. In contrast, crosslink development in the film from surfactant-treated NR was complete after dipping and drying. The resulting films yielded high levels of extractable protein allergens.