Styrene-butadiene rubbers block copolymers

P(S VPD) P(S-b-BR) PSA PSBMA poly(styrene-co-4-vinylpyridine) styrene-butadiene rubber block copolymer poly(sodium acrylate) poly(sec-butyl methacrylate)... 

Butadiene copolymers are mainly prepared to yield mbbers (see Styrene-butadiene rubber). Many commercially significant latex paints are based on styrene—butadiene copolymers (see Coatings Paint). In latex paint the weight ratio S B is usually 60 40 with high conversion. Most of the block copolymers prepared by anionic catalysts, eg, butyUithium, are also elastomers. However, some of these block copolymers are thermoplastic mbbers, which behave like cross-linked mbbers at room temperature but show regular thermoplastic flow at elevated temperatures (45,46). Diblock (styrene—butadiene (SB)) and triblock (styrene—butadiene—styrene (SBS)) copolymers are commercially available. Typically, they are blended with PS to achieve a desirable property, eg, improved clarity/flexibiHty (see Polymerblends) (46). These block copolymers represent a class of new and interesting polymeric materials (47,48). Of particular interest are their morphologies (49—52), solution properties (53,54), and mechanical behavior (55,56). 

A copolymer is made by polymerisation of two monomers, adding them randomly (a random copolymer) or in an ordered way (a block copolymer). An example is styrene-butadiene rubber, SBR. Styrene, extreme left, loses its double bond in the marriage butadiene, richer in double bonds to start with, keeps one. 

In a block copolymer, a long segment made from one monomer is followed by a segment formed from the other monomer. One example is the block copolymer formed from styrene and butadiene. Pure polystyrene is a transparent, brittle material that is easily broken polybutadiene is a synthetic rubber that is very resilient, but soft and opaque. A block copolymer of the two monomers produces high-impact polystyrene, a material that is a durable, strong, yet transparent plastic. A different formulation of the two polymers produces styrene-butadiene rubber (SBR), which is used mainly for automobile tires and running shoes, but also in chewing gum. 

The most important hydrocarbon copolymers are styrene-butadiene rubbers (SBR) produced by free-radical emulsion or anionic polymerization. Anionic polymerization allows the manufacture of styrene-butadiene and styrene-isoprene three-block copolymers. 

Order-disorder transitions and spinodals were computed for linear multi block copolymers with differing sequence distributions by Fredrickson et al. (1992). This type of copolymer includes polyurethanes, styrene-butadiene rubber, high impact polystyrene (HIPS) and acrylonitrile-butadiene-styrene (ABS) block copolymers. Thus the theory is applicable to a broad range of industrial thermoplastic elastomers and polyurethanes. The parameter... 

PS PSF PSU PTFE PU PUR PVA PVAL PVB PVC PVCA PVDA PVDC PVDF PVF PVOH SAN SB SBC SBR SMA SMC TA TDI TEFE TPA UF ULDPE UP UR VLDPE ZNC Polystyrene Polysulfone (also PSU) Polysulfone (also PSF) Polytetrafluoroethylene Polyurethane Polyurethane Poly(vinyl acetate) Poly(vinyl alcohol) poly(vinyl butyrate) Poly(vinyl chloride) Poly(vinyl chloride-acetate) Poly(vinylidene acetate) Poly(vinylidene chloride) Poly(vinylidene fluoride) Poly(vinyl fluoride) Poly(vinyl alcohol) Styrene-acrylonitrile copolymer Styrene-butadiene copolymer Styrene block copolymer Styrene butadiene rubber Styrene-maleic anhydride (also SMC) Styrene-maleic anhydride (also SMA) Terephthalic acid (also TPA) Toluene diisocyanate Ethylene-tetrafluoroethylene copolymer Terephthalic acid (also TA) Urea formaldehyde Ultralow-density polyethylene Unsaturated polyester resin Urethane Very low-density polyethylene Ziegler-Natta catalyst... 

The use of olefin rubbers [18] as good impact modifiers for sPS when used in conjunction with S-B or S-B-S block copolymers, which may be hydrogenated in the butadiene phase, has also been described. Instead of butadiene, isoprene can be used. Examples of the olefinic polymers are polyethylene, ethylene-propylene rubbers (EPR) and polypropylene-(ethylene propylene rubber) block copolymers. Here the styrene block copolymers presumably function as... 

Polymer characterization is an important use of NIR spectrometry. Polymers can be made either from a single monomer, as is polyethylene, or from mixtures of monomers, as are styrene-butadiene rubber from styrene and butadiene and nylon 6-6, made from hexamethylenediamine and adipic acid. An important parameter of such copolymers is the relative amount of each present. This can be determined by NIR for polymers with the appropriate functional groups. Styrene content in a styrene-butadiene copolymer can be measured using the aromatic and aliphatic C—H bands. Nylon can be characterized by the NH band from the amine monomer and the C=0 band from the carboxylic acid monomer. Nitrogen-containing polymers such as nylons, polyurethanes, and urea formaldehyde resins can be measured by using the NH bands. Block copolymers, which are typically made of a soft block of polyester and a hard block containing aromatics, for example, polystyrene, have been analyzed by NIR. These analyses have utilized the... 

The term styrenic describes the family of major plastic products that use styrene as their key building-block PS, expanded polystyrene (EPS), acrylonitrile-butadiene-styrene copolymer (ABS), styrene-acrylonitrile copolymer (SAN), styrene-butadiene rubber (SBR) and unsaturated polyester resin (UP). Among these, UP is the only thermoset and will... 

Samples of styrene butadiene rubber having known styrene content and identified as block copolymers were obtained from Aldrich Chemical Co. Samples of Cariflex SBR were obtained from the Los Angeles Customs laboratory. No specific information is known of additives for the samples except S-1502 which has an aromatic oil additive. Samples were cut into small cubes to fit into the balance pan and weighed between 3 and 12 milligrams. 

Different types of water-based emulsions are used in EPI adhesives. The most common are poly(vinyl acetate) (PVAc) emulsion, ethylene vinyl acetate (EVAc) emulsion, vinyl acetate-acrylate copolymerized (VAAC) emulsion, acrylic-styrene (AcSt) emulsion or styrene-butadiene rubber (SBR) latex or modified versions of these emulsion types [1, 8, 9], It has also been reported that tri- or ter-polymer emulsions like vinyl acetate-butyl acrylate-hydroxypropyl methacrylate or emulsions with different combinations of block copolymers can be used [4], Emulsion polymers containing cross-linking functional groups are especially well suited [4,6, 9]. The choice of emulsion(s) will, to a large extent, influence the adhesive properties such as setting time, bond quality, heat resistance, and moisture resistance. EPI adhesive systems are, however, very complex and the total composition (including the choice of cross-linker) and the interaction between the different components will determine the properties of the adhesive. Due to this it is difficult to describe in detail the effect of choosing one type of emulsion over the other. 

SAN Styrene-acrylonitrile copolymer SBC Styrene-butadiene block copolymer SBR Styrene-butadiene rubber... 

Another important application of Py-GC/MS techniques is the evaluation of contamination caused by industrial wastes consisting of usual polymers such as PVC, PS, poly(vinyl acetate) (PVA), polybutadiene (PB), poly(acrylo-nitrile-co-styrene-co-butadiene) (ABS), styrene-butadiene random (SBR) and styrene-butadiene-styrene block (SBS) copolymers. The presence of synthetic polymers in environmental samples is indicated by anomalously high levels of styrene and benzene in the pyrograms, and by the detection of selected markers (e.g., chlorobenzene for PVC, acetic acid for PVA, benzenebutanenitrile for ABS, cyclohexenylben-zene for styrene-butadiene rubbers), which are useful for better identification of individual polymers. This method was applied to a particular case of contamination in an Italian lake near an industrial area. " " ... 

Europrene SOL, Styrene-butadiene rubber, EniChem ElastomersAmericas, Inc. Europrene SOL T, Styrenic block copolymer, EniChem Elastomers Americas, Inc. Euthylen, Pigment dispersions, BASF Corp., Coatings Colorants Div. 

RS 15 Styrene-butadiene rubber (SBR) block copolymer, 30% styrene. 

The family consists of, in order of market volume, polybutadiene (or butadiene rubber, BR), solution styrene butadiene rubber (SSBR) and styrenic block copolymers (SBC). A further subdivision may be made into those polymers that require vulcanisation (BR, SSBR) and those that do not (SBC). The latter are also known as thermoplastic rubbers as they have rubbery properties below a certain temperature when they soften and may be processed like thermoplastics. 

The chemical properties of the block copolymers are similar to those of unvulcanized styrene-butadiene rubber. Thus the block copolymers are soluble in a range of solvents, including chlorinated and aromatic hydrocarbons, esters and ketones. 

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