Polyurethane Rubber-based

Cellular Cellulose Acetate Conventional adhesives recommended include polyurethanes, synthetic resins, thermoplastics, resorcinol-formaldehyde, nitrile-phenolic, and rubber-based materials (8). 

Polystyrene Although polystyrene is usually bonded by solvent cementing, it can be bonded with vinyl acetate/vinyl chloride solution adhesives, acrylics, polyurethanes, unsaturated polyesters, epoxies, urea-formaldehyde, rubber-base adhesives, polyamide (Versamid-base), polymethylmethacrylate, and cyanoacrylates. The adhesives should be medium-to-heavy viscosity and room-temperature and contact-pressure curing. An excellent source is a Monsanto Company technical information bulletin which recommends particular commercial adhesives for bonding polystyrene to a number of different surfaces. Adhesives are recommended in the fast-, medium-, and slow-setting ranges (10). 

Polysulfone A number of adhesives have been found useful for joining polysufone to itself or to other materials. These include 3M Company s EC 880 solvent-base adhesive, EC 2216 room-temperaturecuring epoxy two-part paste, Bloomingdale Division, American Cyana-mid Company BR-92 modified epoxy with DICY curing agent, or curing agent "Z" (both spreadable pastes), vinyl-phenolics, epoxy-nylons, epoxies, polyimide, rubber-based adhesives, styrene polyesters, resorcinol-formaldehyde, polyurethanes, and cyanoacrylates. The EC 880, EC 2216, and the two BR-92 adhesives are recommended by the polysulfone manufacturer. Union Carbide (16) (17). 

Polymeric compounds are specific sealing materials intended to line or impregnate conducting hardware as well as electric radio circuits for electric insulation. They are based on epoxy and unsaturated polyester resins, liquid organosilicon rubbers and monomers (initial products for S3mthesizing pol3Tnethacrylates and polyurethanes). Compounds based on thermoplastic materials (tar, rosin, cerezin) in the form of solid or wax-like masses, heated for transformation into the liquid state, are confined to this application. 

The elastomeric group of adhesives is based on natural rubber latex and its derivatives or totally synthetic rubber known as SBR (styrene butadiene rubber). There is now a wide range of synthetic rubber adhesives based upon SBR including nitrile and butyl rubber. Another elastomeric adhesive is the versatile polyurethane rubber group. 

Suggested adhesives include modified acrylics, epoxies, polyesters, resorcinol-formaldehyde, furane, phenol-formaldehyde, polyvinyl formal-phenolic, polyvinyl butyral, nitrile rubber-phenolic, polyisobutylene rubber, polyurethane rubber, reclaimed rubber, melamine-formaldehyde, epoxy-phenolic, and cyanoacrylates. For maximum adhesion primers should be used. Nitrile-phenoUcs give excellent bonds if cured under pressure at temperatures of 149 C. Lower-strength bonds are obtained with most rubber-based adhesives. 

Phenylene oxide-based resins (Noryl ) epoxy, polyisocyanate, polyvinyl butyral, nitrile rubber, neoprene rubber, polyurethane rubber, polyvinyUdene chloride, and acrylic. Polyethylene-nitrile rubber, polyisobutylene rubber, flexible epoxy, nitrile-phenolic, and water-based (emulsion) adhesives. Polystyrene for these foams (expanded polystyrene (EPS)), aromatic solvent adhesives (e.g., toluol) can cause collapse of the foam cell walls. For this reason, it is advisable to use either 100% solids adhesives or water-based adhesives based on SBR or polyvinyl acetate. Specific adhesives recommended include urea-formaldehyde, epoxy, polyester-isocyanate, polyvinyl acetate, vinyl chloride-vinyl acetate copolymer, and reclaim rubber. Polystyrene foam can be bonded satisfactorily with any of the following general adhesive types ... 

Examples of vulcanizable elastomers include natural rubber (NR), styrene butadiene rubber (SBR), butadiene rubber (BR), ethylene-propylene-diene monomer-rubber (EPDM), butyl rubber (HR), polychloroprene or neoprene (CR), epichlorohydrin rubber (ECO), polyacrylate rubber (ACM), millable polyurethane rubber, silicone rubber, and flu-oroelastomers. Examples of thermoplastic elastomers include thermoplastic polyurethane elastomers, styrenic thermoplastic elastomers, polyolefin-based thermoplastic elastomers, thermoplastic polyether-ester (copolyester) elastomers, and thermoplastic elastomers based on polyamides. 

Solvent-based dispersions such as polyvinyl acetate. Polyurethane, polyesters, polyethers, acrylic copolymers, Rubber-based adhesives with tackifiers and plasticizers. 

Polyurethane rubbers have now been used as seal materials for some time on account of their unique ability to combine resistance to swelling in oil with high strengths and high stiffnesses. Their ability, in some classes, to be processed as thermoplastics, is also considered useful as manufacture of the seal can then be automated and hence quality is more reproducible. A limitation in their use has been that they depend upon physical types of crosslinking for their elastic and strength properties and when certain specific temperatures are reached these crosslinks rapidly weaken and the polyurethane elastomer melts and fails. At present most rubber seals are made from vulcanized covalently crosslinked rubbers where crosslinks are based on sulphur or carbon, and these do not melt at elevated temperatures, but instead decompose. 

Good anti-mildew and algicide properties are claimed for a non-arsenic-based anti-microbial agent, Amical from Argus Chemical, which is also non-irritating. It is approved by the US EPA for plastics use. Low levels of dosage in plasticized PVC, polyurethane, rubber, and other products prevent embrittlement and premature decay. 

The term polyurethane (PU) covers a number of polymer systems with one common element of chemistry, they contain an —NH—CO—O— linkage. Polyurethanes are used in a variety of applications where the need to form and mould the product into a desired shape makes the use of natural rubber based materials difficult. Such products include soles of shoes such as trainers, conveyor belts, foamed car seats and furniture, wiper blades in printers, etc. By changing the formulation it is possible to change a PU from being a hard material to being a very soft material. 

The photodegradation of polyurethane elastomeric adhesives and its polyblends with poly(vinyl chloride), poly(vinyl alcohol), poly(vinyl acetate) and poly(vinyl acetate-co-vinyl chloride) [652], and rubbers based on poly-(diene urethanes) and poly(ether urethanes) has also been reported [1062]. 

Polyurethane-based adhesives are used to bond polyurethane rubber to the blade. 

Phenylene oxide-based resins (Noryf ) epoxy, polyisocyanate, polyvinyl butyral, nitrile rubber, neoprene rubber, polyurethane rubber, poly viny-lidene chloride, and acrylic... 

Polyurethane epoxy, polyester, polyacrylate, polyhydroxyether, nitrile rubber, butyl rubber, water-based (emulsion), polyurethane rubber, neoprene, SBR, melamine-formaldehyde, and resorcinol-formaldehyde are specific types. Generally, a flexible adhesive should be used for flexible polyurethane foams. Synthetic elastomer adhesives with fast-tack characteristics are available in spray cans. Solvent-based neoprenes are recommended for resistance to stress, water, and weathering. Solvent-based nitriles are recommended for resistance to heat, solvents, and oil. Water-based adhesives... 

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