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Molded elastomer styrene-butadiene copolymer

Styrene butadiene styrene block copolymer --a Aermoplastic elastomer Styrene butadiene styrene block copolymer --a saturated thermoplastic elastomer Styrene maleic anhydride Synthetic polyisoprene Tetrafluorethylene-ethylene copolymers Thick molding compound. [Pg.159]

It is important to appreciate that polymer produced by an anionic chain-growth mechanism can have drastically different properties from one made by a normal free radical reaction. Block copolymers can be synthesized in which each block has different properties. We mentioned in Chapter 4 that Michael Szwdrc of Syracuse University developed this chemistry in the 1950s. Since that time, block copolymers produced by anionic polymerization have been commercialized, such as styrene-isoprene-styrene and styrene-butadiene-styrene triblock copolymers (e.g., Kraton from Shell Chemical Company). They find use as thermoplastic elastomers (TPE), polymers that act as elastomers at normal temperatures but which can be molded like thermoplastics when heated. We will discuss TPEs further in Chapter 7. [Pg.102]

The properties of block copolymers differ from those of a blend of the correponding homopolymers or a random copolymer (Chapter 7) with the same overall composition. An important practical example is the ABA-type styrene/butadiene/styrene triblock copolymer. These behave as thermoplastic elastomers. Ordinary elastomers are cross-linked by covalent bonds, e.g., vulcanization (see Chapter 2) to impart elastic recovery property, as without this there will be permanent deformation. Such cross-linked rubbers are therraosets and so cannot be softened and reshaped by molding. However, solid thermoplastic styrene/butadiene/styrene triblock elastomers can be resoftened and remolded. This can be explained as follows. At room temperature, the triblock elastomers consist of glassy, rigid, polystyrene domains... [Pg.699]

N nylon, PO polyolefin, elastomer, TPU thermoplastic urethane, GF glass fiber, NBR nitrile rubber, MAH maleic anhydride, EPR ethylene-propylene copolymer, l ionomer, M- mineral, ABS acrylonitrile-butadiene-styrene copolymer, PPE poly (phenylene ether), R reinforcement, PTFE poly(tetrafluoroethylene), CF° carbon fiber, PEBA poly(etherblockamide), S silicone, RIPP D reaction injection molding plastic, and ASA acrylate-styrene-acrylonitrile copolymer. [Pg.462]

Silicone plastics Styrene acrylonitrile copolymer St ene-butadiene rubber Styrene butadiene styrene block copolymer Sheet molding compound St50 ene acrylonitrile copolymer Styrene butadiene block copolymer Styrene butadiene styrene block copolymer -a thermoplastic elastomer... [Pg.137]

Styrene block copolymers are the most widely used TPEs. Styrenic TPEs are usually styrene butadiene styrene (SBS), styrene ethylene butadiene styrene (SEES), and styrene isoprene styrene (SIS). Styrenic TPEs usually have about 30 0 percent bound styrene. Principal styrenic TPE markets are molded shoe soles and other footwear, extruded film/sheet and wire/cable covering, and pressure-sensitive and hot-melt adhesives. They are also popular as grips for bike handles, kitchen utensils, clear medical products, and personal care products. Styrenic block copolymer thermoplastic elastomers are produced by Shell Chemical (Kraton), Firestone Synthetic Rubber and Latex, Division of Bridgestone/Firestone (Stereon), Dexco Polymers (Vector), EniChem Elastomers (Europrene), and other companies. [Pg.558]

Early results with cryomicrotomes were described by Cobbold and Mendelson [80]. Polyurethane elastomer, a blend of crystalline and noncrystalline polymers, showed spherulitic textures after sectioning at about -70°C. Injection molded polypropylene (PP) was also sectioned at about -70°C, while polytetrafluoroethylene (PTFE) was sectioned at much lower temperatures. The authors concluded that the technique, though difficult, had potential. Extruded styrene-butadiene-styrene (SBS) copolymer was prepared by cryosectioning with a diamond knife in liquid air at —85 to —115°C, followed by osmium tetroxide vapor staining for one hour [81]. This method revealed the alternating sequence of the polystyrene and polybutadiene lamellae. Odell et al. [82] prepared extruded triblock copolymer by first chemically hardening the polybutadiene, with osmium tetroxide, followed by cryoultramicrotomy to produce 30 nm thick sections which showed fine structure details. Parallel polystyrene rods were observed in the SBS copolymer. Ultramicrotomy and selective staining with osmium tetroxide was also used in the preparation of a binary blend of PP and thermoplastic rubber [83]. [Pg.101]

Styrene Butadiene Thermoplastic n (S/B, SB) A group of thermoplastic elastomers introduced in 1965 (Shell chemical Co, Thermolastic ). They are linear block copolymers of styrene and butadiene, produced by lithium-catalyzed solution polymerization, with a sandwich molecular structure containing a long Polybutadiene center surrounded by shorter polystyrene ends. The materials are available in pellet form for extrusion, injection molding, and blow molding, and S/B sheets are thermoformable. [Pg.708]

A very special type of ABA block copolymer where A is a thermoplastic (e.g., styrene) and B an elastomer (e.g., butadiene) can have properties at ambient temperatures, such as a crosslinked rubber. Domain formations (which serves as a physical crosslinking and reinforcement sites) impart valuable features to block copolymers. They are thermoplastic, can be eaisly molded, and are soluble in common solvents. A domain structure can be shown as in Fig. 2. [Pg.726]

Through copolymerization there can be made materials with different properties than those of either homopolymer, and thus another dimension is added to the technology. Consider, for example, styrene. Polymerized alone, it gives a good electric insulator that is molded into parts for radios, television sets, and automobiles. Copolymerization with butadiene (30%) adds toughness with acrylonitrile (20-30%) increases resistance to impact and to hydrocarbons with maleic anhydride yields a material that, on hydrolysis, is water-soluble, and is used as a dispersant and sizing agent. The copolymer in which butadiene predominates (75% butadiene, 25% styrene) is an elastomer, and since World War II has been the principal rubber substitute manufactured in the United States. [Pg.1033]

Butadiene is widely used in the formation of copolymers with styrene, acryloifitrile, vinyl chloride, and other monomeric substances to which it imparts flexibility to subsequent moldings. The largest use for butadiene is the production of elastomers, such... [Pg.70]

The butadiene-styrene rubber (SBR), or butadiene-acrylonitrile rubber (NBR) and elastomeric graft copolymers were found particularly valuable for impact modification of PP. The PP alloys (with 5-20 wt.% of an elastomer) were reported to have advantageous properties for blow molding of bottles free from brittleness and stress cracking. Blends with natural rubber (NR) require sulfur-curing [4]. Blending with NBR dramatically increased the modulus, but the material was brittle [5]. [Pg.622]

Yu J M, Yu Y, Dubois Ph and Jerome R, Teyssie Ph (1997) Synthesis and characterization of hydrogenated poly[alkyl methacrylate(-6-styrene)-6-butadiene-6-(styrene-6-)alkyl methacrylate] triblock and pentablock copolymers, Polymer 38 3091-3101. 70. Sugimoto H (2004) Thermoplastic elastomer compositions and their power and moldings with good flexibihty, bending, heat and cold resistance, Jpn Kokai Tokkyo Koho JP 2004 002 608, to Sumitomo Chem Co, Ltd. [Pg.25]


See other pages where Molded elastomer styrene-butadiene copolymer is mentioned: [Pg.49]    [Pg.61]    [Pg.167]    [Pg.626]    [Pg.315]    [Pg.742]    [Pg.101]    [Pg.459]    [Pg.315]    [Pg.2238]    [Pg.437]    [Pg.643]    [Pg.42]    [Pg.11]    [Pg.437]    [Pg.271]    [Pg.79]    [Pg.664]    [Pg.475]   
See also in sourсe #XX -- [ Pg.652 ]




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Butadiene copolymers

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Elastomers styrene butadiene copolymer

Elastomers styrenics

Styrene elastomers

Styrene-butadiene

Styrene-butadiene elastomers

Styrene-copolymers

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