摘要:
A copolymer is formed from an isoolefin having from 4 to 7 carbon atoms and an alkylstyrene. The copolymer has a substantially homogeneous compositional distribution. The copolymer has from about 8 to about 12 wt % of alkylstyrene and at least 85 wt % of isoolefin. The copolymer is preferably halogenated with about 1.1 to about 1.5 wt % of a halogen. The copolymer may in elastomeric nanocomposites. To obtain a good dispersion of the nanoclay in a formulated compound, at least one cure accelerator is selected from the group consisting of mercaptobenzothiazole disulfide, mercaptobenzothiazole, cyclohexyl benzothiazole disulfide, dibutyl thiourea, tetramethylthiuram disulfide, 4-4-dithiodimropholine, zinc dimethyldithiocarbamate, and zinc dibutylphosphorodithiate.
摘要:
This invention relates to the preparation of thermoplastic vulcanizates (TPVs) with unique morphological features, more specifically, this invention relates to a method for preparing TPV compositions wherein the mixing of plastomers and elastomers are carried out in solvent with curatives to induce cross-linking.
摘要:
A branched isobutylene-styrenic elastomer with a broad molecular weight distribution is disclosed comprising an interpolymer of an isoolefin monomer as isobutylene, a styrenic monomer such as p-methylstyrene, and a multiolefin such as divinylbenzene. The elastomer has improved green strength, relaxation characteristics, and processability in melt processing, while retaining excellent aging characteristics and barrier properties, and can be used in a blend with a linear isobutylene-p-alkylstyrene elastomer to improve processability of the linear elastomer. Also disclosed are a method for processing the linear elastomer with an effective amount of the branched elastomer to improve processability, and nanocomposites, curable compositions, cured compositions and useful articles formed from the branched elastomer and the linear-branched elastomer blends.
摘要:
This invention relates to a process to polymerize olefins comprising: contacting: (i) propylene and (ii) a mixture comprising, optionally ethylene, and three or more different alpha olefins having 4 to 20 carbon atoms, wherein at least one alpha olefin is present at Z percent or more, based upon the weight of the mixture, where Z=Y+X, where X=(100 divided by the number of alpha olefins present in the mixture) and Y equals 1 to 75, where Z is not more than 95%, with (iii) a metallocene catalyst system.
摘要翻译:本发明涉及一种聚合烯烃的方法,包括:(i)丙烯和(ii)包含任选的乙烯和三种或更多种具有4至20个碳原子的不同α-烯烃的混合物的混合物,其中至少存在一种α-烯烃 基于混合物的重量,Z = Y + X,其中X =(100除以混合物中存在的α烯烃的数量),Y等于1至75,其中Z不大于 (iii)茂金属催化剂体系。
摘要:
A method of lowering MFR response of a high melt flow rate polymer producing metallocene catalyst is provided. The method includes contacting the metallocene catalyst with a sufficient quantity of α,ω-diene monomer such that when the catalyst composition is contacted with polymerizable reactants under suitable polymerization conditions, the resulting polymer has an MFR rate in the range of 0.1 to 19. Hydrogen and ethylene may also be present in the polymerization. Additionally a catalyst composition is provided which includes a high melt flow rate polymer producing metallocene catalyst and a sufficient quantity of α,ω-diene monomers such that when the catalyst composition is contacted with a monomer under polymerization conditions, the resulting polymer has an MFR rate in the range of 0.1 to 19.
摘要:
A polyolefin composition is provided which consists essentially of isotactic polypropylene and, optionally, one or more comonomers, wherein the total comonomer content of the polyolefin composition is from 0 to 20 mole percent, and further, wherein the weight average branching index g′ for the lower molecular weight region of the polyolefin composition is less than 0.93. Additionally, a process is provided for producing a polyolefin composition comprising: a) contacting, in solution, at a temperature from about 90° C. to about 120° C., propylene monomers with a catalyst composition comprising a first chiral, stereorigid transition metal catalyst compound capable of producing isotactic polypropylene; b) copolymerizing the product of a) with propylene and, optionally, one or more copolymerizable monomers, in a polymerization reactor under suitable polypropylene polymerization conditions using a second chiral, stereorigid transition metal catalyst capable of producing isotactic polypropylene; and c) recovering a branched olefin polymer.
摘要:
An elastomeric nanocomposite contains: (a) at least one elastomer comprising units derived from isoolefins having from 4 to 7 carbon atoms; (b) at least 10 phr of a carbon black; and (c) at least 1 phr of a nanoclay; wherein when the nanocomposite is used in an article, the article has a gas permeation coefficient of 80.0 cc*mm/[m2-day] at 40° C. The carbon black may be graphitized to reduce interactions between the carbon black and the nanoclays. The elastomeric nanocomposite may, with or without the use of the graphitized carbon black, may calendared or extruded in such a manner as to orient the nanoclay platelets within the composition such that the oriented nanoclay elastomer nanocomposite has an orientation parameter of greater than 0.15.
摘要翻译:弹性纳米复合材料包含:(a)至少一种弹性体,其包含衍生自具有4至7个碳原子的异烯烃的单元; (b)至少10phr的炭黑; 和(c)至少1phr的纳米粘土; 其中当在制品中使用纳米复合材料时,制品在40℃下的气体渗透系数为80.0cc * mm / [m2-天]。炭黑可以石墨化以减少炭黑和纳米粘土之间的相互作用。 弹性体纳米复合材料可以在使用或不使用石墨化碳黑的情况下以这样的方式进行压延或挤出,以使组合物内的纳米粘土片晶定向,使得取向的纳米粘土弹性体纳米复合材料具有大于0.15的取向参数。
摘要:
The present invention relates to a process for preparing a thermoplastic vulcanizate (TPV) comprising: contacting a thermoplastic polymer, a cross-linkable elastomer, at least one curative, and at least one cure activator in a solvent to form Composition A. The solvent is then removed, and thereafter the cross-linkable elastomer is at least partially cured. The average particle size of the cross-linkable elastomer is 10 microns or less after the solvent is removed.
摘要:
The present invention relates to a process for preparing a thermoplastic vulcanizate (TPV) comprising: contacting a thermoplastic polymer, a cross-linkable elastomer, at least one curative, and at least one cure activator in a solvent to form Composition A. The solvent is then removed, and thereafter the cross-linkable elastomer is at least partially cured. The average particle size of the cross-linkable elastomer is 10 microns or less after the solvent is removed.
摘要:
The present invention relates to a process for preparing a thermoplastic vulcanizate (TPV) comprising: contacting a thermoplastic polymer, a cross-linkable elastomer, at least one curative, and at least one cure activator in a solvent to form Composition A. The solvent is then removed, and thereafter the cross-linkable elastomer is at least partially cured. The average particle size of the cross-linkable elastomer is 10 microns or less after the solvent is removed.