Provided is a rubber composition for sealing material which contains 100 parts by mass of a rubber component, 50 to 140 parts by mass of silica, 1 to 20 parts by mass of a silane coupling agent, and 15 to 35 parts by mass of carbon black. The rubber component is preferably an ethylene-propylene-diene rubber.

A cross-linkable rubber composition for a seal material which is used at an oilfield or gas well comprising a nitrile group-containing copolymer rubber which contains ,-ethylenically unsaturated nitrile monomer units 10 to 60 wt % and has an iodine value of 120 or less, an ,-ethylenically unsaturated carboxylic acid metal salt (B), and an organic peroxide cross-linking agent (C) is provided. According to the present invention, it is possible to provide a rubber composition which is excellent in shapeability, is high in durability against hydrogen sulfide and other corrosive gases, and is suitable for application as a seal material which is used at an oilfield or gas well.

The invention relates to a crosslinkable rubber composition (I) based on an elastomer and to the process for preparing same. The composition (I) comprises a crosslinking system and a thermoplastic phase which is dispersed into particles, having a melting point MP or softening point SP, a glass transition temperature Tg and optionally a crystallisation temperature Tc, the system comprising sulfur when the elastomer is unsaturated and the phase comprises saturated chains, and a peroxide when the elastomer is saturated, the composition (I) comprising the product of: a) a melt reaction by thermomechanical working of the elastomer and other ingredients except for the system, comprising heating the mixture to a maximum temperature Ta that is greater than MP or SP, then b) mechanical working of the mixture obtained, with addition of the system. The particles comprise filaments or fibrils, the temperature of the mixture during b) being temporarily greater than Tc when the phase is crystalline, or than Tg when it is amorphous.

The invention relates to an efficient process for the preparation and isolation of rubber particles formed in aqueous media and highly pure rubbers obtained thereby. The invention further relates to copolymer products comprising the same or derived therefrom.

A sealing apparatus is provided. The sealing apparatus is arranged between two members facing each other for sealing a space between the two members. The sealing apparatus comprises a sealing body in contact with the space, in which the sealing body has a tensile strength of 10 MPa or more measured in accordance with the provisions of JIS K 6251: 2017, an elongation at break of 200% or more measured in accordance with the provisions of JIS K 6251: 2017, a TR10 temperature of 40 C. or lower in a low-temperature elastic recovery test, measured in accordance with the provisions of JIS K 6261-4: 2017, and a compression set at 100 C. with an elapsed time of 70 hours in a shape of a G25 O-ring as described in the provisions of JIS B 2401-1: 2012, measured in accordance with the provisions of JIS K 6262: 2013, of 40% or less.

Embodiments provide rubber sealants and rubber sealant formulations for use in high pressure hydrogen storage and transportation. Example sealant formulations include mixtures of ethylene propylene diene monomers (EPDMs) or EPDM-like materials, optional thermally conductive fillers, optional hydrogen barrier fillers, reinforcing fillers, liquid rubbers, antioxidants, optional abrasion resistance additives, and curing agents (e.g., cross-linking agents). Example formulations are capable of peroxide curing to produce thermosetting elastomers with excellent thermomechanical properties. Example sealants provide very low equilibrium hydrogen concentrations and reduced swelling.

A seal material for a semiconductor manufacturing device is made of a rubber composition containing fluororubber and phenol resin powder. The content of the phenol resin powder is 1 part by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the fluororubber. The average particle size of the phenol resin powder is 1 m or more and 20 m or less.