Abstract: Pore-free rubber articles are prepared by dip-molding in a dipping medium that includes a vulcanizing agent, then by immersing the dip former in a heated liquid bath that is chemically inert. A particularly effective liquid bath is molten inorganic salt. In addition, the tensile properties of an article of vulcanized rubber can be improved to an unusually effective degree by immersing the already vulcanized article in a solution of a vulcanizing agent to cause the rubber of the article to absorb or imbibe the vulcanizing agent from the solution, and then immersing the rubber and the imbibed vulcanizing agent in a heated liquid bath to increase the degree of vulcanization.

Abstract: Pore-free rubber articles are prepared by dip-molding in a dipping medium that includes a vulcanizing agent, then by immersing the dip former in a heated liquid bath that is chemically inert. A particularly effective liquid bath is molten inorganic salt. In addition, the tensile properties of an article of vulcanized rubber can be improved to an unusually effective degree by immersing the already vulcanized article in a solution of a vulcanizing agent to cause the rubber of the article to absorb or imbibe the vulcanizing agent from the solution, and then immersing the rubber and the imbibed vulcanizing agent in a heated liquid bath to increase the degree of vulcanization.

Abstract: Pore-free rubber articles are prepared by dip-molding in a dipping medium that includes a vulcanizing agent, then by immersing the dip former in a heated liquid bath that is chemically inert. A particularly effective liquid bath is molten inorganic salt. In addition, the tensile properties of an article of vulcanized rubber can be improved to an unusually effective degree by immersing the already vulcanized article in a solution of a vulcanizing agent to cause the rubber of the article to absorb or imbibe the vulcanizing agent from the solution, and then immersing the rubber and the imbibed vulcanizing agent in a heated liquid bath to increase the degree of vulcanization.

Abstract: Pore-free rubber articles are prepared by dip-molding in a dipping medium that includes a vulcanizing agent, then by immersing the dip former in a heated liquid bath that is chemically inert. A particularly effective liquid bath is molten inorganic salt. In addition, the tensile properties of an article of vulcanized rubber can be improved to an unusually effective degree by immersing the already vulcanized article in a solution of a vulcanizing agent to cause the rubber of the article to absorb or imbibe the vulcanizing agent from the solution, and then immersing the rubber and the imbibed vulcanizing agent in a heated liquid bath to increase the degree of vulcanization.

Abstract: Medical devices of synthetic rubber are prepared from cis-1,4-polyisoprene by dip molding without the use of sulfur containing components. The devices have surprisingly favorable tensile characteristics despite what is known in regard to synthetic cis-1,4-polyisoprene. In addition, the absence of both the proteins present in natural rubber and the sulfur components that are typically used in vulcanization of both natural rubber and cis-1,4-polyisoprene of the prior art renders the devices freely usable without causing the user to suffer Type I or Type IV allergic reactions that typically arise from contact with natural rubber.

Abstract: Rubbery polymers in hydrocarbon solutions are emulsified in aqueous liquids and converted to latices by partitioning the emulsion through a membrane of selective permeability to the hydrocarbon solvent relative to both water and the polymer, thereby removing the hydrocarbon solvent from the emulsion. The foaming that is often associated with removing hydrocarbon solvent from aqueous emulsions by conventional means is thus avoided. Membrane partitioning mechanisms that are useful for this application include those involving both nonporous and microporous membranes, those passing the solvent both as a liquid and as a gas, those drawing off the permeate as both a liquid and a gas, and various combinations of these methods.