Abstract: A process involves adding a peroxide masterbatch to a molten blend of a fluorocarbon elastomer and a thermoplastic material. The peroxide masterbatch contains greater than or equal to 5% weight percent organic peroxide, further contains a fluorocarbon elastomer, and typically also contains a crosslinker containing at least two sites of olefinic unsaturation. The fluorocarbon elastomer in the molten blend and in the peroxide masterbatch may be the same or different. After the peroxide masterbatch is added to the molten blend, the combination is mixed at a temperature and for a time sufficient to effect cure of the fluorocarbon elastomers. By using a masterbatch, a faster and more uniform dispersion of peroxide curative is possible due to pre-dispersion of peroxide in the elastomer phase, which leads to shaped articles having improved mechanical properties.

Abstract: A thermoplastically processable cured rubber composition comprises a crosslinked or cured urethane polymer dispersed in a matrix made of a thermoplastic polymeric material. In one aspect, the matrix forms a continuous phase and the crosslinked urethane polymer is in the form of particles forming a non-continuous phase. The processable rubber compositions can be made by a process of dynamic vulcanization of a urethane prepolymer material in the presence of the thermoplastic matrix material. The process involves combining a urethane prepolymer, a curing agent capable of reacting with the urethane prepolymer, and a thermoplastic material to form a mixture, and heating the mixture at a temperature and for a time sufficient to effect reaction between the curing agent and the prepolymer. Mechanical energy is supplied to the mixture during the heating step so that the crosslinking or curing of the urethane prepolymer occurs while the prepolymer and thermoplastic are undergoing a mixing.

Abstract: A processable rubber composition contains a double cured fluorocarbon elastomer dispersed in a matrix of a thermoplastic polymeric material. The cured elastomer contains repeating units derived from one or more fluorine-containing monomers, and further contains low levels of a peroxide cure site that contains at least one of a C—Cl bond, a C—Br bond, a C—I bond, and an olefin. In one embodiment the matrix forms a continuous phase and the vulcanized elastomeric material is in the form of particles forming a non-continuous phase. In various embodiments, the processable compositions are thermally processed into molded articles that exhibit a high degree of base resistance, especially a high degree of resistance to degradation of physical properties upon exposure to fluids containing strong nucleophiles such as amines.

Abstract: An elastomer blend is made by admixing fluoroelastomer and fluorinated silicone polymer (with optional filler and/or conductive particulate) into a polymeric admixture in weight ratios to provide a low vaporous hydrocarbon permeation rate and high thermal strain value in thermally robust elastomer cured from the blend. The blend is of especial use for making gaskets for use in high stress conditions at elevated operating temperatures.

Abstract: A curable fluorocarbon elastomer is dynamically cured in the presence of a major amount of a non-curing thermoplastic material and a minor amount of a second fluorocarbon elastomer that does not cure under the dynamic vulcanization conditions. The non-curing elastomer is preferably present at from 1 to 20 parts based on 100 parts of the curing fluorocarbon elastomer. Processable rubber compositions comprise a continuous phase of a thermoplastic material, particles of a cured fluorocarbon elastomer dispersed in the continuous phase, and an uncured fluorocarbon elastomer at a level of 10 parts or less per 100 parts of the cured fluorocarbon elastomer. Shaped articles such as gaskets and seals are produced by thermoplastic processing of the processable rubber compositions.

Abstract: A cured magnetizable admixture of elastomeric thermoplastic, dispersed magnetizable particulate, and optional dispersed hydrophobic material (such as ethylene acrylic monomer rubber or ethylene-vinyl acetate copolymer) provides elastic elongation of not less than about 50 percent at break and water swell of not greater than about 10 percent after curing in magnetizable articles such as target wheels. The magnetizable composition beneficially combines mechanical and durability advantages of traditionally-used thermoset elastomer-based magnetic compounds, under the range of conditions needed for vehicle encoder applications, with the processing and manufacturing advantages of engineered thermoplastics.

Abstract: Admixtures either of a plastic and an elastomer, a plurality of thermoplastics, or a plurality of elastomers are formed into a shaped item for an article (such as a dynamic seal, a static seal, a gasket, a pump diaphragm, a hose, or an o-ring), and the thermoplastic is then cross-linked (cured). Radiation (preferably, electron beam radiation) is used for the cross-linking and for generating bi-modal molecules from the elastomer and the thermoplastic when both a thermoplastic and an elastomer are in the admixture.

Abstract: Processable rubber compositions contain a vulcanized fluorocarbon elastomer and functional filler dispersed in a matrix of a thermoplastic polymeric material. In one embodiment the matrix forms a continuous phase and the vulcanized elastomeric material is in the form of particles forming a non-continuous phase. The compositions are made by combining a curative, an uncured fluorocarbon elastomer, a functional filler and a thermoplastic material, and heating the mixture at a temperature and for a time sufficient to effect vulcanization of the elastomeric material, while mechanical energy is applied to mix the mixture during the heating step. Shaped articles such as seals, gaskets, O-rings, and hoses may be readily formed from the rubber compositions according to conventional thermoplastic processes such as blow molding, injection molding, and extrusion.

Abstract: Two-phase or single-phase admixtures of a plastic and an elastomer, two or more thermoplastics, or two or more elastomers are irradiated (preferably with electron beam radiation) to cross-link the thermoplastic and, in the case of elastomer and thermoplastic admixtures, generate bi-modal molecules having moieties derived from both the elastomer and the thermoplastic.

Abstract: A bi-modal compound is provided having an elastomeric moiety and a second moiety derived from any of a metal, a ceramic, and thermoplastic. At least one free radical site is generated (preferably with electron beam radiation) on an elastomer molecule to provide the elastomeric moiety; and a metal, ceramic, or thermoplastic are then bonded to the free radical site.

Abstract: A gasket coating admixture of fluoroelastomer particulate, inert particulate, curing agent, and metallic oxide reduction-agent optionally admixed with any of microspheres, PTFE particles, and ferric oxide is applied to a carrier and cured to provide a coating for components such as gaskets. The admixtures provide a basis for designed cured coatings having internally differentiated regions interbonded by cured elastomer. The coating admixture has especial value in coating gasket carriers to form single component gaskets for internal combustion engines or in coating transmission separator plate interfaces.