摘要:
Halogenated isobutylene-co-alkylstyrene polymer, preferably halogenated isobutylene-co-methylstyrene polymer, even more preferably brominated isobutylene-co-paramethylstyrene polymer (BIMS), blends thereof, and blends with a second rubber, show improved heat resistance compared to butyl inner tube compositions, and retain the superior barrier properties of butyl inner tube compositions versus inner tube compositions with butyl/EP blends.
摘要:
The invention generally relates to thermoplastic blends having improved properties. Optionally, these blends may be dynamically vulcanized. More specifically, this invention is directed to a composition comprising a blend of chloromethylated(styrene-isobutylene) polymer and a thermoplastic resin selected from the group consisting of polyamides, polyesters, polycarbonates, polysulfones, polyacetals, polyacetones, acrylonitrile-butadiene styrene resins, polyphenylene oxide, polyphenylene sulfide, styrene-acrylonitrile resins, styrene-maleic anhydride resins, polyamides, aromatic polyketones, ethylene vinyl alcohol polymer and mixtures thereof. Tires and tire components such as air permeation prevention films comprising these compositions are also provided.
摘要:
The improved green strength, green elongation, and green relaxation properties of isobutylene-based elastomers at elevated temperatures along with improved aging and barrier properties are achieved by blending semi-compatible, semi-crystalline copolymers with the isobutylene elastomers. The semi-crystalline copolymers are typically copolymers of ethylene and an alpha-olefin having from 4 to 16 carbon atoms. The improved properties are maintained in subsequent rubber compounds containing said blends and are particularly useful in tire and pharmaceutical container applications.
摘要:
A process for catalytic recovery in a phase transfer process wherein heterogeneous reactions in a liquid-liquid two phase reaction systems using a phase transfer catalyst is improved by separating the two liquid phases with a membrane which retains the catalyst while passing the aqueous polar liquid thereby allowing easy recovery of the phase transfer catalyst. The reaction is carried out between reactants selectively soluble in the different phases, one of the reactants being transferred into the other phase by means of a phase transfer catalyst which is soluble in said polar liquid phase with the one reactant. The phases are separated after completion of the reactions by adding water to the two-phase reaction system to dissolve out the polar liquid phase containing the phase transfer catalyst into an aqueous phase. Further, the phase transfer catalyst is separated from the polar liquid phase by passing the aqueous polar liquid phase through a membrane that retains the transfer catalyst while passing the polar liquid.
摘要:
Thermoplastic elastomer compositions which have good high temperature end use and good oil swell resistance are made by blending a high melting thermoplastic polymer containing a non-polar rubber and a polar rubber. Alternatively, a high melting thermoplastic polymer containing a non-polar rubber or a polar rubber or both is blended with a polyolefin thermoplastic polymer containing a non-polar rubber, or a polar rubber, or both. The composition is dynamically vulcanized. The cured multi-component thermoplastic elastomer compositions exhibit good end use properties such as hardness, tensile strength, modulus, flexibility.
摘要:
Graft copolymers having cationic units pendant to the backbone chain are disclosed. These polymers are prepared by reacting a polymer containing halogenated paramethylstyrene units in the chain, e.g., a brominated copolymer of isobutylene and para-methylstyrene, with an anionically polymerized polymer made using an organolithium initiator compound having the formula R.sub.1 R.sub.2 Z R.sub.3 --Li where R.sub.1 and R.sub.2 are alkyl radicals, R.sub.3 is a direct link or an organic radical and Z is nitrogen or phosphorous. Reaction of the anionically polymerized polymer having an R.sub.1 R.sub.2 Z R.sub.3 --end group with the halogenated polymer leads to graft polymers coupled by a quaternary ammonium or phosphonium groups.
摘要翻译:公开了具有垂直于主链的阳离子单元的接枝共聚物。 这些聚合物通过使链中含有卤代对甲基苯乙烯单元的聚合物例如异丁烯和对甲基苯乙烯的溴化共聚物与使用具有式R1 R2 Z R3-Li的有机锂引发剂化合物制成的阴离子聚合聚合物反应制备,其中R 1 R2为烷基,R3为直链或有机基团,Z为氮或磷。 具有R1R2Z R3-端基的阴离子聚合聚合物与卤化聚合物的反应导致通过季铵或鏻基团偶联的接枝聚合物。
摘要:
Vulcanizable tire innerliner compositions are described which are essentially free of halogen atoms or contain a reduced halogen content. The innerliners contain a saturated elastomeric interpolymer of a C.sub.4 -C.sub.7 isomonoolefin, e.g., isobutylene and a para-alkylstyrene e.g., para-methylstyrene, which contains benzylic ester functionality having the structure: ##STR1## wherein R.sub.2 and R.sub.3 are independently selected from hydrogen or C.sub.1 to C.sub.6 alkyl, and R.sub.4 is selected from hydrogen, C.sub.1, to C.sub.28 alkyl, aryl or C.sub.2 to C.sub.28 alkenyl.Innerliners of the invention provide excellent impermeability to air, heat aging properties and good adhesion to tire carcass stock required for tire innerliners, and are also essentially free of halogen or contain low halogen content thereby reducing environmental concerns occasioned by the incineration of used tires.
摘要:
Crystalline propylene polymer compositions having improved impact strength and improved clarity are disclosed. The composition is prepared by melt blending a propylene polymer, e.g., polypropylene, and from about 1 to 35 wt % of an elastomeric interpolymer of a C.sub.4 to C.sub.8 isomonoolefin, e.g., isobutylene, and a para alkystyrene comonomer, e.g., para-methylstyrene. The interpolymer preferably contains a benzylic functional group such as halogen (bromine). The composition may also contain from about 0.5 to 15 wt % of the amide reaction product of an organic acid-grafted propylene polymer, e.g., maleic anhydride grafted polypropylene, and a polyfunctional primary amine.
摘要:
Intervulcanized compositions having improved curing efficiency are prepared by the free radical curing of a mixture of an ethylenically unsaturated diolefin polymer such as natural or synthetic rubber and a saturated or low unsaturation polymer such as an isobutylene/para-methylstyrene copolymer which contains functional groups pendant to the polymer chain. These functional groups contain an olefinic or vinyl double bond positioned alpha, beta to a substituent group which activates the double bond towards free radical addition reactions with the diolefin polymer. Preferred functionality includes benzylic ester functionality represented by the structure: ##STR1## wherein R.sub.2 and R.sub.3 are independently selected from hydrogen or C.sub.1 to C.sub.6 alkyl, and R.sub.4 is selected from hydrogen, C.sub.1 to C.sub.28 alkyl, aryl or C.sub.2 to C.sub.28 alkenyl.
摘要:
An olefin polymerization process is provided wherein an olefin chargestock is contacted with an organic compound polymerization initiator, a Lewis acid coinitiator and a pyridine compound such as 2,6-di-tert-butylpyridine to produce homopolymers, copolymers or block copolymers having a narrow molecular weight distribution.