Styrene-butadiene copolymers adhesives

This type of adhesive is generally useful in the temperature range where the material is either leathery or mbbery, ie, between the glass-transition temperature and the melt temperature. Hot-melt adhesives are based on thermoplastic polymers that may be compounded or uncompounded ethylene—vinyl acetate copolymers, paraffin waxes, polypropylene, phenoxy resins, styrene—butadiene copolymers, ethylene—ethyl acrylate copolymers, and low, and low density polypropylene are used in the compounded state polyesters, polyamides, and polyurethanes are used in the mosdy uncompounded state. 

G-5—G-9 Aromatic Modified Aliphatic Petroleum Resins. Compatibihty with base polymers is an essential aspect of hydrocarbon resins in whatever appHcation they are used. As an example, piperylene—2-methyl-2-butene based resins are substantially inadequate in enhancing the tack of 1,3-butadiene—styrene based random and block copolymers in pressure sensitive adhesive appHcations. The copolymerization of a-methylstyrene with piperylenes effectively enhances the tack properties of styrene—butadiene copolymers and styrene—isoprene copolymers in adhesive appHcations (40,41). Introduction of aromaticity into hydrocarbon resins serves to increase the solubiHty parameter of resins, resulting in improved compatibiHty with base polymers. However, the nature of the aromatic monomer also serves as a handle for molecular weight and softening point control. 

FIGURE 23.17 Styrene-butadiene copolymer (SBR) peel adhesion test piece after first appl3nng a gas decompression (GD) procedure and then peel testing. 

Styrene-Butadiene Copolymer Elastomers. SBR elastomers are employed in low-cost contact adhesives suitable for less-demanding applications—such as when exposure to elevated temperature is not likely, and when a bond of moderate strength is adequate. They can be dissolved in aliphatic hydrocarbon solvents and used to bond solvent-sensitive substrates like expanded polystyrene. 

Since this work of adhesion has been correlated (41, 44) with the adhesive strength, we can presumably use Wad to estimate the theoretical maximum adhesive strength between a rubber and a resin for all four systems discussed in this paper. For example, the work of adhesion between polystyrene and polybutadiene is 67 dyne/cm., and that between polystyrene and styrene-butadiene copolymer is 69 dyne/cm. 

Aqueous dispersions of poly(vinyl acetate) and vinyl acetate-ethylene copolymers, homo- and copolymers of acrylic monomers, and styrene-butadiene copolymers are the most important types of polymer latexes today. Applications include paints, coatings, adhesives, paper manufacturing, leather manufacturing, textiles and other industries. In addition to emulsion polymerization, other aqueous free-radical polymerizations are applied on a large scale. In suspension polymerization a water-irnrniscible olefinic monomer is also polymerized. However, by contrast to emulsion polymerization a monomer-soluble initiator is employed, and usually no surfactant is added. Polymerization occurs in the monomer droplets, with kinetics similar to bulk polymerization. The particles obtained are much larger (>15 pm) than in emulsion polymerization, and they do not form stable latexes but precipitate during polymerization (Scheme 7.2). 

For electrostatic and steric stabilization, the particles can be viewed effectively as colloids consisting of a soft and deformable corona surrounding a rigid core. Colloidal particles with bulk elastomeric properties are also available. These particles, which are generally of submicron size, are developed and used as reinforcement additives to improve the Impact resistance of various polymer matrices [28-30]. The rubber of choice is often a styrene/butadiene copolymer. The presence of chemical groups at the matrix-filler interface leads to improved adhesion between them. Typically, the addition of about 30% by volume of these elastomeric particles increases the impact strength of a brittle glassy polymer like polystyrene by up to a factor of 10. For some applications, particles with more complex architecture have been... 

Preliminary experiments were done on adhesion of the two elastomers considered in Section 24.2.1, polyisoprene and styrene-butadiene copolymer [9]. One sheet was fully crosslinked before contact Then the joints were made with the second uncrosslinked sheet... 

The most important application of SBR is in car tires and tire products, but there is also widespread use of the rubber in mechanical and industrial goods. SBR latexes, which are emulsions of styrene-butadiene copolymers (containing about 23-25% styrene), are used for the manufacture of foam rubber backing for carpets and for adhesive and molded foam applications. 

Chem. Descrip. Carboxylated styrene-butadiene copolymer latex Uses Associative thickener for adhesives, suitable for coated and uncoated paper. Mylar, cellulose acetate, metalized polyester, aluminum, nonskid coating, and mastic substrates Features Very efficient... 

Synonyms Carboxylated styrene-butadiene copolymer Uses Nonwoven binder for textiles In Interior vapor barrier primer sealers and flat wall paint binder for paper coatings food-pkg. adhesives/ paper... 

Butadiene/acrylonitrile copolymer adhesive, food-packaging food containers D-Mannitol adhesive, furniture Urea-formaldehyde resin adhesive, glass Epoxy resin Polyvinyl acetate adhesive, glass fibers Styrene/PVP copolymer adhesive, grinding disks Animal glue adhesive, hair care Polyquaternlum-14 adhesive, heat-resistance Silicone elastomer... 

Pressure sensitive and contact adhesives are made from a variety of polymers including acrylic acid esters, polyisobutylene, polyesters, polychloroprene, polyurethane, silicone, styrene-butadiene copolymer and natural rubber. With the exception of acrylic acid ester adhesives which can be processed as solutions, emulsions, UV curable 100% solids and silicones (which may contain only traces of solvents), all remaining rubbers are primarily formulated with substantial amounts of solvents such as hydrocarbon solvents (mainly heptane, hexane, naphtha), ketones (mainly acetone and methyl ethyl ketone), and aromatic solvents (mainly toluene and xylene). 

Waterborne dispersed polymers include both synthetic polymer dispersions and natural rubber. Synthetic polymer dispersions are produced by emulsion polymerization. A substantial part of the synthetic polymer dispersions is commercialized as dry products these include SBR for tires, nitrile rubbers, about 10% of the total PVC production, 75% of the total ABS and redispersable powders for construction materials. Carboxylated styrene-butadiene copolymers, acrylic and styrene-acrylic latexes and vinyl acetate homopolymer and copolymers are the main polymer classes commercialized as dispersions. The main markets for these dispersions are paints and coatings, paper coating, adhesives and carpet backing. 

Other polymers that can provide delayed-tack adhesives include styrene-butadiene copolymers, polyvinyl acetate, polystyrene, and polyamides. Solid (crystalline) plasticizers for these adhesives include dicyclohexyl phthalate, diphenyl phthalate, A-cyclohexyl-p-toluene sulfonamide, and o/p-toluene sulfonamide. Adhesives with different heat-activation temperatures could be obtained because of the range of melting points available. Delayed-tack adhesives have a large number of uses, such as coating paper for labels on bread packages, cans, etc. 

Rosin family s most common form of adhesive is colophony, a hard amorphous substance derived from the oleoresin of the pine tree. This material is applied in solvent solution form as a hot-melt mastic. It has poor resistance to water, is subject to oxidation, and has poor aging properties. Plasticizers are usually added to reduce its brittleness. Bond strengths are moderate and develop rapidly. These materials are used as temporary adhesives in bonding paper and as label varnishes. They are also used as components of PSAs based on styrene-butadiene copolymers and in hot-melt adhesives and tackifiers. These materials have been largely replaced by synthetic-resin adhesives. One specialized form of rosin adhesive is Canada Balsam, covered by the obsolete Military Specification MIL-C-3469C, titled Canada Balsam. This material was intended for cementing optical elements. 

The binder, therefore, must have the following properties good adhesion to fibre and pigment in the dry state, and in water and solvent a soft, non-tacky handle elasticity lightfastness, clarity and no colour compatibility with, and stability towards, other ingredients in the mix. Some styrene butadiene copolymer rubbers and vinyl latices are used successfully but the most suited are the acrylics. The polymers are usually either self-cross-linking (with heat) or incorporate a cross-linkable resin such as melamine-formaldehyde. 

Polyamides and saturated polyesters can be toughened with ABS, ethylene-propylene copolymers/terpolymers or EPDM rubbers grafted with maleic anhydride to increase the dispersion and adhesion of the modifier. Styrene-butadiene copolymers are also effective. The notched Izod impact strength of polyamide 6-6 can be increased more than 20-fold by impact modifiers, whereas short glass fibres often reduce the impact strength, even though they increase the modulus. 

Chemical types of heat-activated adhesives include polyolefin, polyamide, polyester, PU, and styrene butadiene copolymers. These are described in Table 13.9. There are copolymer variants of each type, allowing a wide range of applications and performance properties. 

Styrene butadiene copolymers (SBCs) Available as both a pressure-sensitive and nonpressure-sensitive adhesive, good flexibdity and toughness, resistant to both hot and cold temperatures. Used to join difficult-to-bond substrates (e.g., polyolefin fibre). Medium... 

Duradene Styrene-butadiene copolymers, Firestone Dural Rigid PVC, AlphaGary Duralron Polyimide, DSM Durez Powder and flake phenolic resin. Occidental Duro-Lam Hot-melt laminating adhesives. National Starch Duro-O-Set Polyvinyl acetate and ethlyene. National Starch DWF Dow window film, Dow Dylark Styrene-maleic anhydride copolymers, Arco Dylene Polystyrene, NOVA... 

Polystyrene and polyurethane foam and mineral wool tiles are applied to interior and exterior for decoration and insulation purposes (sound and heat). Solventless adhesives based on poly(vinyl acetate), polyacrylate, or styrene-butadiene copolymer emulsions are preferred for this purpose. The viscosity of the adhesives must be adjusted to give the required wet tack. 

Ceramic wall tiles are apphed either with cement mortar adhesives or with adhesives based on styrene-butadiene copolymer or polyacrylate emulsions. Tile adhesives must be pasty and thixotropic to prevent the tiles from sUpping but allow positioning. 

Maleic anhydride has been grafted on polybutadiene and styrene-butadiene copolymers as a method to obtain improved coatings and adhesives for glass fibers. Treating low-molecular-weight styrene-... 

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