Abstract: Cured, latex-blended compositions featuring a fluoroelastomer and a fluoroplastic, and curable core-shell polymers having a fluoroelastomer precursor-containing shell and a fluoroplastic-containing core.

Abstract: A fluorocarbon polymer which includes: repeating units derived from one or more perfluorinated ethers of the formula CF2═CFO—(CF2)m—(O(CF2)p)n—ORf1 wherein Rf1 is a perfluorinated (C1-C4)alkyl group, m=1-4, n=0-6, and p=1-2; and repeating units derived from vinylidene fluoride; wherein the polymer has a glass transition temperature of −50° C. or lower and an oxygen to carbon ratio of at least about 0.2.

Abstract: The extrusion of polymeric materials, especially thermoplastic polymeric materials, requires a number of physical attributes in the polymer to be controlled during extrusion to effect desirable surface characteristics on the extruded polymer. Extrusion additives have been provided for the improvement of these attributes and characteristics. The present invention describes an additive system for extrudable thermoplastic polymers, extrudable polymer compositions containing the additive system, and extrusion processes using polymers containing the additive system of this invention. The extrusion additive of the present invention comprises: (i) a fluorocarbon polymer, (ii) a poly(oxyalkylene) polymer, (iii) magnesium oxide, and (iv) optionally a stabilizer. The extrudable composition of the invention comprises: (A) an extrudable polymer (e.g., a predominant amount, such as at least 50% by weight of solids), and (B) an effective amount of the stabilized processing aid (extrusion additive).

Abstract: A polymer processing aid composition, a melt processable polymer composition that uses the polymer processing aid, and a method of improving the melt processability of a thermoplastic polymer are provided. The polymer processing aid composition comprises a multimodal fluoropolymer that preferably comprises interpolymerized units derived from an ethylenically unsaturated fluoromonomer tetrafluoroethylene and at least one ethylenically copolymerizable alpha-olefin monomer.

Abstract: A method for increasing the adhesion of a first layer comprising a vinylidene fluoride containing fluoropolymer to a second layer comprising a curable elastomer is described. The method comprises adding a dehydrofluorinating composition to the curable elastomer, contacting the layers and curing the layered article so formed. The resulting multilayer compositions and articles are also disclosed.

Abstract: The present invention describes a novel process for the preparation of perfluoro allyl ethers. The process involves providing a hydrogen-containing precursor comprising at least one 1,2-dichloro alkyl ether moiety, fluorinating the precursor to provide a perfluorinated intermediate, and dechlorinating the perfluorinated intermediate to the corresponding perfluorinated ether. A reaction product of a perfluorinated olefin and an allyl ether may also be used as a precursor. Such a reaction product is chlorinated before the fluorination step. Perfluoro vinyl or allyl ethers may be used in place of the perfluorinated olefin. Novel perfluoro alkoxy compounds are also described.

Abstract: The present invention describes a novel process for the preparation of perfluorovinyl ethers. The process involves providing a hydrocarbon precursor that may be partially halogenated, fluorinating the precursor to provide a perfluorinated intermediate, and converting the perfluorinated intermediate to the desired perfluorinated ether. Novel perfluorovinyl ethers are also provided.

Abstract: The process for the recovery of highly fluorinated carboxylic acids from off-gas streams, in which the off-gas is brought into contact with an alkaline washing solution of density >1.15 g/cm3 so that the salt of the highly fluorinated carboxylic acid settles out as a separate phase, proceeds particularly advantageously when the alkaline washing solution is a potassium carbonate solution.

Abstract: A multimodal fluoroplastic terpolymer composition is provided. The terpolymer can be extruded at high extrusion speeds without having to reduce its molecular weight. The terpolymer is useful by itself; in combination with conductive fillers to provide an electrostatically dissipative composition; and as a polymer processing aid. The polymer has a low molecular weight component, a high molecular weight component and, optionally an ultra-high molecular weight component.

Abstract: A composite article is provided which includes a blend component comprising a vinylidene fluoride containing fluoropolymer and a substantially non-vinylidene fluoride containing fluoropolymer, and a component including a substantially non-fluorinated polymer having pendant amine groups intimately bonded to the blend component. Increased adhesion is observed by a greater peel strength value between the blend component and a substantially non-vinylidene fluoride containing fluoropolymer when compared to a peel strength value between a substantially non-vinylidene fluoride containing fluoropolymer and the substantially non-fluorinated polymer having pendant amine groups.

Abstract: Non-free flowable, non-dusting molding powders with a bulk density of more than 450 g/l are obtained when a suspension polymer of tetrafluoroethylene with a content of 0.01 to 1% by weight of units of at least one perfluoro(alkyl-vinyl) ether is ground to a particle diameter of 10 to 50 .mu.m and agglomerated in water.

Abstract: Compositions and techniques useful to effectively recycle crosslinked (i.e., vulcanized or cured) fluoroelastomers are disclosed. The invention utilizes an additive system that includes a cure-enhancing additive, a crosslinking agent, and an accelerator.

Abstract: A composite article is provided which includes a blend component having first and second surfaces and a substantially non-fluorinated polymer component adhered to the first surface of the blend component, wherein the substantially non-fluorinated polymer component has an exposed surface. The blend component includes a first hydrogen containing fluoropolymer; and a substantially non-fluorinated polymer having one or more pendant primary or secondary amine groups. Increased adhesion is observed by a peel strength value between the blend component and the substantially non-fluorinated polymer component when compared to a peel strength value between a component consisting of a fluoropolymer and a component consisting of a substantially non-fluorinated polymer having pendant primary or secondary amine groups.

Abstract: Sheet-like structures comprising rubber layers and fluoropolymer layers can be produced by employing, as adhesive layer, a mixture comprising a rubber and a thermoplastic fluoropolymer having a melting point <250.degree. C.

Abstract: Highly fluorinated carboxylic acids can be removed from exhaust gas streams by scrubbing with concentrated alkali solutions if these alkali solutions have a density high enough for the salt of the highly fluorinated carboxylic acid to separate out as an independent phase. An apparatus suitable therefor contains a scrubber and a separation vessel which is advantageously equipped with a conveying element, a collection vessel connected via an overflow and a circulation line for the scrubbing liquor.

Abstract: This invention provides curable fluoroelastomer compositions comprising: (a) a fluorine-containing polymer or blend of fluorine-containing polymers each comprising interpolymerized units derived from one or more fluorine-containing ethylenically unsaturated monomers; (b) at least one organo-onium compound such as those selected from the group consisting of ammonium, arsonium, phosphonium, stibonium, amino-phosphonium, phosphorane (e.g. triarylphosphorane), iminium, and sulfonium compounds; and (c) one or more aryl, allyl or alkyl carbonate-blocked compounds as crosslinking agents. Methods of curing fluoroelastomer compositions, and articles made therefrom are also described.

Abstract: The present invention provides a process of curing a fluorocarbon elastomeric composition comprising: providing a mixture of a saturated elastomeric gum comprising repeating interpolymerized units derived from vinylidene fluoride and a perfluorinated ether of the formula CF.sub.2 .dbd.CF(CF.sub.2).sub.m --O--R.sub..function. wherein m =1-4, R.sub..function. is a perfluorinated aliphatic group optionally containing O atoms, at least one crosslinking agent, and an acid acceptor; shaping the mixture; and curing the resulting shaped article.

Abstract: Labile end groups in fluorinated thermoplastics, in particular carboxyl and acid fluoride groups, are converted into carboxamide groups when the polymer is treated with an aqueous, ammonia-containing solution. The after-treated products have a pale color, do not cause corrosion during processing and can easily be taken from the molds in transfer molding.

Abstract: A pressure sensitive adhesive that includes:(a) the polymerization product of:(i) 25-98 parts by weight of an acrylic acid ester of a monohydric alcohol whose homopolymer has a T.sub.g less than 0.degree. C.;(ii) 2-75 parts by weight of a non-polar ethylenically unsaturated monomer whose homopolymer has a solubility parameter of no greater than 10.50 and a T.sub.g greater than 15.degree. C.; and(iii) 0-5 parts by weight of a polar ethylenically unsaturated monomer whose homopolymer has a solubility parameter of greater than 10.50 and a T.sub.g greater than 15.degree. C.; and(b) at least one tackifier that is miscible in the polymerization product at room temperature.

Abstract: A unified, composite tape structure is provided. The tape comprises two outer pressure-sensitive adhesive layers joined via melt processing. A method of making the tape comprising the use of melt processing is also disclosed. In the method a plurality of layers are melt processed and simultaneously joined to form the unified composite.