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Sbs block copolymer in TEM. Kraton polymers are styrenic block copolymer (SBC) consisting of polystyrene blocks and rubber blocks. The rubber blocks consist of polybutadiene, polyisoprene, or their hydrogenated equivalents. The tri-block with polystyrene blocks at both extremities linked together by a rubber block is the most important polymer ...
Butyl rubber (copolymer of isobutene and isoprene, IIR) Halogenated butyl rubbers (chloro butyl rubber: CIIR; bromo butyl rubber: BIIR) Styrene-butadiene rubber (copolymer of styrene and butadiene, SBR) Nitrile rubber (copolymer of butadiene and acrylonitrile, NBR), also called Buna N rubbers. Hydrogenated nitrile rubbers (HNBR) Therban and Zetpol
Styrene-butadiene is a commodity material which competes with natural rubber. The elastomer is used widely in pneumatic tires. This application mainly calls for E-SBR, although S-SBR is growing in popularity. Other uses include shoe heels and soles, gaskets, and even chewing gum. [3]
[61]: 102–104 Several copolymers are used based on styrene: The brittleness of homopolymeric polystyrene is overcome by elastomer-modified styrene-butadiene copolymers. Copolymers of styrene and acrylonitrile are more resistant to thermal stress, heat and chemicals than homopolymers and are also transparent. Copolymers called ABS have similar ...
For example, in the free-radical copolymerization of styrene maleic anhydride copolymer, r 1 = 0.097 and r 2 = 0.001, [11] so that most chains ending in styrene add a maleic anhydride unit, and almost all chains ending in maleic anhydride add a styrene unit. This leads to a predominantly alternating structure.
1,3-butadiene is normally copolymerized with other types of monomers such as styrene and acrylonitrile to form rubbers or plastics with various qualities. The most common form is styrene-butadiene copolymer, which is a commodity material for car tires. It is also used in block copolymers and tough thermoplastics such as ABS plastic.
The styrene-butadiene materials possess a two-phase microstructure due to incompatibility between the polystyrene and polybutadiene blocks, the former separating into spheres or rods depending on the exact composition. With low polystyrene content, the material is elastomeric with the properties of the polybutadiene predominating.
The initial radical anion of styrene converts to a dianion (or equivalently disodio-) species, which rapidly added styrene to form a "two – ended living polymer." An important aspect of his work, Szwarc employed the aprotic solvent tetrahydrofuran , which dissolves but is otherwise unreactive toward the organometallic intermediates.