Polystyrene-butadiene copolymer

Fig. 24.2. A two-phase polymer alloy, mode by co-polymerising styrene and butadiene in polystyrene. The precipitates ore a polystyrene-butadiene copolymer.

Definitions of propellant abbreviations PSB = Polystyrene-butadiene copolymer AP = Ammonium perchlorate A1 - Aluminum ... 

The easiest technique to establish a polymer-photochromic molecule (PC) interaction is to dissolve the photochrome in a polymer solution from which the solvent is evaporated afterwards. DHI 7 has been incorporated by this technique into poly(methyl)- or poly( -butyl methacrylate), vinylidene chloride, acrylonitrile (Saran F), polycarbonate, and polystyrene-butadiene copolymer (Panarez). 

In the annual figures (11) polystyrene resins are disclosed from 1942 through 1950. Styrene-acrylonitrile copolymers are disclosed in 1950. Care must be exercised in using these figures to see where styrenated alkyds are classified. Polystyrene polyesters are disclosed in 1945 polystyrene-maleic anhydride resins are disclosed in 1946 styrene-alkyd polyesters are disclosed in 1949 and 1950 polystyrene-butadiene copolymers are disclosed in 1949 and 1950. 

Standard window glass 9.8-13.8 28 Polystyrene-butadiene copolymer 15.7 6... 

Fig. 12-26 Effect of blending polymers, polystyrene, and polystyrene-butadiene copolymer [19].

Polymorphism 6 Polyoxymethylene 279, 281 Polyoxypropylene 279, 281 Polypentene-1 279,281 Polypeptides 146,333 Polyphenylene oxide 279, 281 Polypropylene 12, 264, 268, 279, 281 Polysaccharides 329 Polystyrene 257, 269 Polystyrene-butadiene copolymer 257, 269, 274... 

Poly(styrene-fc-butadiene) copolymer-clay nanocomposites were prepared from dioctadecyldimethyl ammonium-exchanged MMT via direct melt intercalation [91]. While the identical mixing of copolymer with pristine montmorillonite showed no intercalation, the organoclay expanded from 41 to 46 A, indicating a monolayer intercalation. The nanocomposites showed an increase in storage modulus with increasing loading. In addition, the Tg for the polystyrene block domain increased with clay content, whereas the polybutadiene block Tg remained nearly constant. 

We have considerable latitude when it comes to choosing the chemical composition of rubber toughened polystyrene. Suitable unsaturated rubbers include styrene-butadiene copolymers, cis 1,4 polybutadiene, and ethylene-propylene-diene copolymers. Acrylonitrile-butadiene-styrene is a more complex type of block copolymer. It is made by swelling polybutadiene with styrene and acrylonitrile, then initiating copolymerization. This typically takes place in an emulsion polymerization process. 

A polystyrene-poly(ethylene,l-butene)-polystyrene triblock copolymer is produced by the selective hydrogenation of the corresponding triblock copolymer in which the center block consists of random placements of 1,2-poly(1,3-butadiene) and 1,4-poly (1,3-butadiene) units. 

Polymeric particles can be constructed from a number of different monomers or copolymer combinations. Some of the more common ones include polystyrene (traditional latex particles), poly(styrene/divinylbenzene) copolymers, poly(styrene/acrylate) copolymers, polymethylmethacrylate (PMMA), poly(hydroxyethyl methacrylate) (pHEMA), poly(vinyltoluene), poly(styrene/butadiene) copolymers, and poly(styrene/vinyltoluene) copolymers. In addition, by mixing into the polymerization reaction combinations of functional monomers, one can create reactive or functional groups on the particle surface for subsequent coupling to affinity ligands. One example of this is a poly(styrene/acrylate) copolymer particle, which creates carboxylate groups within the polymer structure, the number of which is dependent on the ratio of monomers used in the polymerization process. 

Copolymerization allows the synthesis of an almost unlimited number of different products by variations in the nature and relative amounts of the two monomer units in the copolymer product. A prime example of the versatility of the copolymerization process is the case of polystyrene. More than 11 billion pounds per year of polystyrene products are produced annually in the United States. Only about one-third of the total is styrene homopolymer. Polystyrene is a brittle plastic with low impact strength and low solvent resistance (Sec. 3-14b). Copolymerization as well as blending greatly increase the usefulness of polystyrene. Styrene copolymers and blends of copolymers are useful not only as plastics but also as elastomers. Thus copolymerization of styrene with acrylonitrile leads to increased impact and solvent resistance, while copolymerization with 1,3-butadiene leads to elastomeric properties. Combinations of styrene, acrylonitrile, and 1,3-butadiene improve all three properties simultaneously. This and other technological applications of copolymerization are discussed further in Sec. 6-8. 

Most polystyrene products are not homopolystyrene since the latter is relatively brittle with low impact and solvent resistance (Secs. 3-14b, 6-la). Various combinations of copolymerization and blending are used to improve the properties of polystyrene [Moore, 1989]. Copolymerization of styrene with 1,3-butadiene imparts sufficient flexibility to yield elastomeric products [styrene-1,3-butadiene rubbers (SBR)]. Most SBR rubbers (trade names Buna, GR-S, Philprene) are about 25% styrene-75% 1,3-butadiene copolymer produced by emulsion polymerization some are produced by anionic polymerization. About 2 billion pounds per year are produced in the United States. SBR is similar to natural rubber in tensile strength, has somewhat better ozone resistance and weatherability but has poorer resilience and greater heat buildup. SBR can be blended with oil (referred to as oil-extended SBR) to lower raw material costs without excessive loss of physical properties. SBR is also blended with other polymers to combine properties. The major use for SBR is in tires. Other uses include belting, hose, molded and extruded goods, flooring, shoe soles, coated fabrics, and electrical insulation. 

Solution (S-SBR) consists of styrene butadiene copolymers prepared in solution. A wide range of styrene-butadiene ratios and molecular structures is possible. Copolymers with no chemically detectable blocks of polystyrene constitute a distinct class of solution SBRs and are most like slyrcnc-buladicne copolymers made by emulsion processes. Solution SBRs with terminal blocks of polystyrene (S-B-S) have the properties of self-cured elastomers. They are processed like thermoplastics and do not require vulcanization. Lithium alkyls are used as the catalyst. 

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... 

Polystyrene and Styrene-Butadiene Copolymer Pair Systems... 

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. 

When only spectroscopic methods are used, they are able to identify polymer components with respect to their chemical nature. However, in many cases, they are unable to answer the question whether two chemical structures are combined to yield a copolymer or a blend or both. For example, analyzing a rubber mixture one is able to identify styrene and butadiene as the monomer units. However, using FTIR or NMR it is impossible to decide if the sample is a mixture of polystyrene (PS) and polybutadiene (PB),or a copolymer of styrene and butadiene, or a blend of a styrene-butadiene copolymer and PB. For the latter case, even the copolymer composition cannot be determined just by running a FTIR or NMR spectrum. 

Plastics copolymerized from styrene, butadiene and acrylonitrile offer a wide application scope, thus high-impact polystyrene (HIPS, styrene-butadiene copolymer), styrene-... 

An urethane-based pressure-sensitive adhesive composed of a liquid hydroxytelechelic polybutadiene and a polyisocyanate does not require a solvent in coatings onto label sheets. This polymer together with the (polystyrene-co-butadiene) copolymer and a polyisocyanate was applied in steel coatings 239 240>. 

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