| 摘要 |
PROBLEM TO BE SOLVED: To provide a rubber plug for powdery medicine which does not have a volatile substance even under a reduced pressure, and is excellent in moldability by a method wherein to a polymer for which bromine is added to a copolymer of isobutylene and paramethylstyrene, an inorganic reinforcing agent, a refined chlorinated polyethylene, and liquid isobutylene are blended by specified pts.wt., and the polymer is valcanization-molded. SOLUTION: A polymer for which bromine is added to a copolymer of isobutylene and paramethylstyrene, is made a major component, and 20 pts.wt. or less of refined chlorinated polyethyrene is blended to the major component, and in addition, 5-60 pts.wt. of an inorganic reinforcing agent, and 2-10 pts.wt. of liquid isobutylene are blended, and by a valcanization-molding, a rubber plug for powdery medicine is manufactured. In this case, the constitution ratio for the polymer, while isobutylene is made the major component, is such as that paramethylstyrene is in a range of 5-7.5wt.%, and bromine is in a range of 0.8-2wt.%., and the feature is that the average molecular weight of the liquid isobutylene is 1000 or less, and the average solution viscosity is 30PA.S or less. By this method, the storage stability for medicine, which is required as a rubber plug for medical use, can be improved. |
