A combined sealing member is provided that includes a composition comprising two or more polyolefin elastomers selected from the group consisting of a dense, a micro-dense and a dynamic silane-crosslinked polyolefin elastomer having a respective density of less than 0.90 g/cm.sup.3, less than 0.70 g/cm.sup.3, and less than 0.60 g/cm.sup.3. The combined sealing member exhibits a compression set of from about 5.0% to about 35.0%, as measured according to ASTM D 395 (22 hrs @ 70 C.).

A static sealing member is provided that includes a composition having a silane-crosslinked polyolefin elastomer with a density less than 0.90 g/cm.sup.3. The static sealing member can exhibit a compression set of from about 5.0% to about 35.0%, as measured according to ASTM D 395 (22 hrs @ 70 C.). The silane-crosslinked polyolefin elastomer can include a first polyolefin having a density less than 0.86 g/cm.sup.3, a second polyolefin having a crystallinity less than 40%, a silane crosslinker, a grafting initiator, and a condensation catalyst.

A microdense sealing member is provided. The microdense sealing member includes a composition having a foamed silane-crosslinked polyolefin elastomer with a density less than 0.70 g/cm.sup.3. The microdense sealing member can exhibit a compression set of from about 5.0% to about 35.0% measured according to ASTM D 395 (22 hrs @ 70 C.). The foamed silane-crosslinked polyolefin elastomer can be produced from a blend including a first polyolefin having a density less than 0.86 g/cm.sup.3, a second polyolefin having a crystallinity less than 60 C., a silane crosslinker, a grafting initiator, a condensation catalyst, and a microencapsulated foaming agent.

A combined sealing member is provided that includes a composition comprising two or more polyolefin elastomers selected from the group consisting of a dense, a micro-dense and a dynamic silane-crosslinked polyolefin elastomer having a respective density of less than 0.90 g/cm.sup.3, less than 0.70 g/cm.sup.3, and less than 0.60 g/cm.sup.3. The combined sealing member exhibits a compression set of from about 5.0% to about 35.0%, as measured according to ASTM D 395 (22 hrs @ 70 C.).

The present invention is directed to a sealing composition comprising: (a) a polysiloxane; (b) a reactive polysiloxane comprising at least one reactive functional group; and (c) water; wherein the weight ratio of polysiloxane to reactive polysiloxane is from 2.7:1 to 4:1. Also disclosed are coated substrates and methods of coating a substrate.

Provided is a fluoroelastomer crosslinkable composition containing: a polyol-crosslinkable fluoroelastomer (a); and a cross-linking agent (b), wherein the cross-linking agent (b) is at least one selected from the group consisting of a compound represented by the following general formula (b) and a salt of the compound with an alkali metal, an alkaline earth metal, or an onium compound.

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(wherein all symbols are as defined in the specification).

Provided are a perfluoroelastomer composition containing a perfluoroelastomer, a peroxide crosslinking agent, a co-crosslinking agent that is a diolefin compound, and an organic pigment; and a sealing material containing a crosslinked product of the perfluoroelastomer composition.

A seal material composition according to the present invention includes: an epoxy compound including an epoxy group; and a polymerizable epoxy curing agent including a polymerizable functional group configured for cross-linking the epoxy groups and for radical polymerization in a single molecule.

Provided are sealant compositions that include a first component and second component. The first component contains a polysulfide, a polythioether, or a copolymer or combination thereof containing pendant or terminal thiol groups, while the second in component contains an ethylenically-unsaturated compound and either the first or second component further contains a photoinitiator. Alternatively, the second component can contain a polyepoxide and either the first or second component can contain a photolatent base and a photosensitizer. The first or second component further contains a colorant that substantially reflects or substantially transmits light over the wavelength range from 350 nm to 500 nm. These compositions can provide cure-on-demand sealant formulations that comply with Class B sealant regulations on color, provide an acceptable depth of cure, and allow two-part mixing to be easily distinguishable.

Provided are a perfluoroelastomer composition which contains 100 parts by weight of a perfluoroelastomer containing a constituent unit derived from a nitrile group-containing monomer, and 0.01 to 5 parts by weight of ketjen black; and a sealing material including a crosslinked product of the perfluoroelastomer composition.