摘要:
The present invention relates to a shaped article for high purity applications containing at least one peroxide curable compound containing a substantially gel-free butyl polymer. In another of its aspects, the present invention relates to a sealing material and a medical device containing at least one peroxide-curable compound containing a substantially gel-free butyl polymer. In still another of its aspects, the present invention relates to a fuel cell containing at least one peroxide curable compound containing a substantially gel-free butyl polymer. In still another of its aspects, the present invention relates to halogen-free and sulfur-free shaped articles.
摘要:
A butyl polymer having improved processability is described, together with a process for production thereof. The butyl polymer derived from a reaction mixture which contains: (i) a monomer mixture comprising a C4 to C7 monoolefin monomer (preferably isobutylene) and a C4 to C14 multiolefin monomer (preferably isoprene); (ii) a multiolefin cross-linking agent (preferably divinyl benzene); and (iii) a chain transfer agent (preferably diisobutylene (2,2,4-trimethyl-1-pentene)). The subject butyl polymer has an improved balance of cold flow, filler dispersion, extrusion rate and die swell.
摘要:
An elastomeric polymer composition that exhibits improved processability and green strength comprises: from about 95 to about 70 parts by weight of one rubbery polymer selected from the group consisting of butyl rubber, chlorinated butyl rubber and brominated butyl rubber and from about 5 to about 30 parts by weight of a block copolymer having an elastomeric polyisobutylene midblock and two plastomeric endblocks of polymerized monovinylidene aromatic monomers and star-shaped block copolymers having from three to six arms wherein the inner elastomeric blocks are polyisobutylene and the outer plastomeric blocs are polymerized monovinylidene aromatic monmers for a total of 100 parts by weight of the rubbery polymer and the block copolymer. Vulcanizates of the composition that exhibit reduced permeability to gases and improved tear strength are provided together with a process for their production.
摘要:
Block copolymers compose a polyisobutylene rubbery soft segment of M.sub.n of about 5,000 to above 500,000 and glassy hard segments of M.sub.n of about 5,000 or higher and usually about 10,000 to 35,000 or more, are made by preparing a living polymer block of the polyisobutylene and then polymerizing on said living polyisobutylene block the glassy hard segments by adding thereto an electron donor having a donor number of 15 to 50 and then adding and polymerizing the monomers for the glassy hard segments. The monomers for the glassy hard segments are styrene and its derivatives and indene and its derivatives and mixtures thereof.
摘要:
The present invention is directed to a method of preparing a functionalized elastomer, comprising the steps of A) obtaining a diene-based elastomer; B) mixing the diene-based elastomer with a halogenating agent to form an intermediate elastomer; and C) mixing the intermediate elastomer with a dienophile comprising a filler-active functional group to form a functionalized elastomer.
摘要:
The present invention relates to arborescent polymers and to a process for making same. In one embodiment, the present invention relates to arborescent polymers formed from at least one inimer and at least one isoolefin that have been end-functionalized with a polymer or copolymer having a low glass transition temperature (Tg), and to a process for making such arborescent polymers. In another embodiment, the present invention relates to arborescent polymers formed from at least one inimer and at least one isoolefin that have been end-functionalized with less than about 5 weight percent end blocks derived from a polymer or copolymer having a high glass transition temperature (Tg), and to a process for making such arborescent polymers.
摘要:
The present invention achieves increased filler interaction by incorporating a small amount (a few units per chain of rubbery polymer) of a conjugated triene monomer, such as alloocimene, randomly throughout the polymer chain of a rubbery polymer or at the chain ends of the rubbery polymer. The incorporation of the conjugated triene monomer leads to the formation of a polymer containing highly reactive conjugated diene units. These conjugated diene units can chemically react with carbon black leading to superior reinforcement. Alternatively, these conjugated diene units can be used for functionalization of the polymer with silica interactive/reactive groups using Diels Alder reactions. This functionalization of the rubbery polymer can conveniently be conducted in a mixer, such as a Banbury mixer, a mill mixer, or the like. The present invention more specifically discloses a rubbery polymer having repeat units which are comprised of (1) an olefin monomer selected from the group consisting of conjugated diolefin monomers and monoolefin monomers and (2) a conjugated triene monomer. The subject invention further reveals a rubbery composition which is comprised of the reaction product of (I) a rubbery polymer having repeat units which are comprised of (1) an olefin monomer selected from the group consisting of conjugated diolefin monomers and monoolefin monomers and (2) a conjugated triene monomer and (II) a dienophile and/or dienophile which is functionalized with a group which is capable of reacting with a filler selected from the group consisting of carbon black, silica, starch, and cellulose.
摘要:
A halogenated butyl polymer having improved properties, the butyl polymer derived from a monomer mixture comprising a C4 to C8 monoolefin monomer, a C4 to C14 multiolefin monomer and a styrenic monomer with a catalyst system to produce the butyl polymer. The improved properties include faster cure, higher maximum torque, higher delta torque, relatively stable modulus over time, improved hot air aging properties and improved aged flexure properties. These improved properties are believed to result from direct interaction between the styrenic moieties in the polymer backbone with a crosslinking agent added to vulcanize the halogenated butyl rubber.
摘要:
The present invention is directed to a method of making a rubber composition, comprising the steps of A) obtaining a diene-based elastomer selected from the group consisting of natural rubber, synthetic polyisoprene, polybutadiene, solution polymerized styrene-butadiene rubber (SSBR), and emulsion polymerized styrene-butadiene rubber (ESBR); B) mixing the diene-based elastomer with a halogenating agent to form an intermediate elastomer; and C) mixing the intermediate elastomer with a carbon black. There is further disclosed a rubber composition made by the foregoing method, and a pneumatic tire comprising the rubber composition.
摘要:
An improved process is provided for the bromination of isoolefin-conjugated diolefin polymers by brominating said polymer in solution in selected halogen-containing hydrocarbons as solvent. There is also provided an improved product of said process wherein the brominated polymer contains not less than 80 percent of the bound bromine atoms in a form suitable to participate in the vulcanization of the polymer and wherein not less than 70 percent of the bound conjugated diolefin units are similarly so brominated.