Nitrile rubber sealant

The use of plasticisers, with other than PVC applications, is extensive. Many polar rubber sealants or caulking materials are plasticised in order to make them more pliable, e.g., polysulfides, polychloroprene (Neoprene ), nitrile rubber. Esters, similar to those employed with PVC, are used to render cellulose diacetate ("Acetate") overhead projection sheets more flexible. 

Rubber-like materials now superseding the traditional mastics and putties used in the building industry. Such sealants (also termed mastics) are based on butyl rubber, liquid polysulphides, silicone rubbers, polybutylene, nitrile rubbers and plasticised vinyl polymers. SEBS... 

Compression set is atypical feature of PVC sealants because gelled PVC has plastic properties (no rubbery behavior). Addition of crosslinked nitrile rubber adds rubbery particles which are able to reduce compression set. 

Test formulations for pumpable sealants based on liquid natural rubber, liquid polybutadiene and liquid nitrile rubber are shown in Tables 8.10, 8.11, and 8.12, respectively. 

Sealant Applications. The repair of engine bodies has been reported using a nitrile rubber/ phenolic composition as a sealant. The wing fuel tanks of Cl30 aircraft have also used nitrile rubber/phenolic materials to seal the tanks.Finally, electrolyte leakage in a sheet battery has been prevented using nitrile rubber/ phenolic adhesives. 

Elastomers used to a minor extent as the principal binder in sealants include styrene-butadiene rubber (SBR), nitrile rubber, and reclaim rubber. 

Nitrile Rubbers. These require high solvent levels to produce gunnable sealants, hence are little used. Reclaim rubber goes into asphaltic sealants. 

An amphoteric fluorinated surfactant in silicone rubber sealants makes the seal soil resistant [283]. An anionic fluorinated surfactant prevents leakage of mineral oil around nitrile rubber seals [284]. 

Silaprene . [Uniroyal] Industrial adhesives and sealants based on chloro-prene, PVC acrylic, nitrile, natural rubber, SBR, PC, ABS, urediane, or epoxy or blends. 

Thermoplastic rubber block copolymers, with completely new adhesive performance, were developed in 1965 [21]. The first commercial product was Shell Chemical s Kraton 101, of styrene polybutadiene-styrene composition. This development led to the carboxy-terminated nitrile (CTBN) rubber modifiers used to flexibilize epoxy and other brittle resin adhesives in the late 1960s. Today, the thermoplastic rubber block copolymer adhesives are used in hot melt-, solvent- and water-based adhesives, and as hot melt- and solvent-based sealants. Major applications are as pressure-sensitive adhesives, construction adhesives and sealants, and general assembly adhesives. 

Ctiem. Descrip. Silicone-based, clay-supported emulsion Uses Dewebber, antifoam for natural latex and syn. blends, esp. nitrile formulations and high vise, latexes in latex dipping industry (mfg. of medical, household, and industrial gloves, toys, balloons) defoamerfor pulp/paper mfg., influent and effluent wastewater treatment, boiler water treatment, paints, adhesives, and sealants food-contact rubber articles... 

Bentonite thickening agents are used in various water based adhesives, caulks and sealants including those based on proteins and starch, polyvinyl acetate emulsions, natural rubber latexes, acrylic emulsions, neoprene emulsions, butyl emulsions, nitrile emulsions, and SBR emulsions. 

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