Rubber Medicine Bottle Stoppers

Different Medicine Bottle Stopper Materials:

Natural Rubber Stoppers: High levels of impurity ( Protein ), Quality varies, natural rubber latex is allergic, no suit to produce medicine bottle stoppers.  Not recommend

Silicone Stoppers: Silicone stoppers only react with strong alkali or hydrofluoric acid, not dissolves in water or other materials, non-toxic and odorless, stable chemical properties, good thermal stability, and higher mechanical strength. Silicone Stoppers also can up to FDA, LFGB grade.
However, silicone materials stoppers have high absorbing capacity, which not suit to all medicine bottle stoppers .  Not recommend

Synthetic Polyisoprene Rubber Stopper: Poor Air tightness and need sulphur  vulcanization make the use of the limitation.   Not recommend

Isobutylene Isoprene Rubber & Butyl rubber stoppers: need sulphur and accelerant vulcanization. Not recommend.

Chlorinated Butyl Rubber Stopper: Need clean vulcanizing agent for vulcanization.  Not recommend

Bromotutyl Rubber Stopper: Need less clean vulcanizing agent for vulcanization.    Recommend