Polystyrene and styrene-butadiene copolymer

Polystyrene and Styrene-Butadiene Copolymer Pair Systems... 

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. 

Using this technique, Crompton and Myers have described a technique (Method 53) for determining styrene monomer and a wide range of other volatiles in conventional polystyrene and styrene-butadiene copolymers. ... 

METHOD 53 - DETERMINATION OF STYRENE MONOMER AND OTHER VOLATILES IN CONVENTIONAL POLYSTYRENE AND STYRENE -BUTADIENE COPOLYMERS. GAS CHROMATOGRAPHY. ... 

Determination of styrene monomer and other volatiles in conventional polystyrene and styrene-butadiene copolymers. Gas chromatography... 

In this paper graft copolymerization onto both polystyrene and styrene-butadiene block copolymer will be discussed. It will be shown that radical processes do not permit the addition of monomers onto polystyrene and that one must use anionic initiation in order... 

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

Low profile plastics are added to reduce shrinkage during cure. They are normally thermoplastics that include polyvinyl acetates, polymethyl methacrylate, and copolymers with other acrylate, vinyl chloride-vinyl acetate copolymers, polyurethane, polystyrene, polycaprolactone, cellulose acetate butyrate, saturated polyester, and styrene butadiene copolymers. More details about the low profile additive (LPA) mechanism are published in the literature. ... 

The high sensitivity provided by supersonic beam spectrometry permitted the detection of minor species, thus styrene monomer is produced from poly alpha methylstyrene by cleavage of a methyl group and by proton rearrangement. Because the ablation is carried out at high temperatures it is possible to obtain results on thermally stable polymers such as poly-p-methyl styrene. The technique was applied to polystyrene foam, styrene-butadiene copolymers and acrylonitrile-butadiene-styrene terpolymers. 

The SAN and ABS cxjpolymers aantain approximately 25 wt% of acrylonitrile and polybutadiene rubber in amounts up to 20 wt%. Other styrene copolymers of industrial importance include styrene—maleic anhydride copolymer (SMA), styrene-divinylbenzene copolymer, acrylic—styrene-acrylonitrile terpolymer, and styrene-butadiene copolymer. Recently, metallocene catalysts have been developed to synthesize syndiotactic polystyrene (sPS). The polymerization process and process conditions have major effects on polymer properties and process economy. For styrene homopolymerization and copolymerization, various types of polymerization reactors are used commercially. 

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. 

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. 

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. 

Figures 4A and 4B are the ultra-thin cross-sections of OsOi+-stained two-stage (styrene//styrene-butadiene) and (styrene-butadiene/ /styrene) latex particles at the stage ratio of 50/50 (LS-10 and LS-11), respectively. Latex samples were mixed with a polymerizable monomer mix of butyl and methyl methacrylates, cured, and microtomed for examination. Figure 4A shows particle cross-sections much smaller than the actual particle size of LS-10. It appears that since the embedding monomer solution was a solvent for polystyrene, the continuous polystyrene phase was dissolved and small S/B copolymer microdomains were left behind. This is further evidence that the second-stage S-B copolymers phase-separated as microdomains within the first-stage polystyrene phase, as shown in Figures 1A and 1A. Figure 4B shows somewhat swollen and deformed particle cross-sections, suggesting that the first-stage cross-linked S-B copolymers were a continuous phase. Indeed, the former (LS-10) behaved like a hard latex, but the latter (LS-11) behaved like a soft latex.

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. 

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. 

The first patent on HIPS, a blend of synthetic rubber and transparent polystyrene, was granted in Great Britain as early as 1912. The first graft copolymerization of styrene in the presence of rubber was carried out by Ostromislensky [5]. The decline in the demand for styrene monomer and styrene-butadiene rubber and the simultaneous availability of natural rubber on the world market in the late 1940s drove the development of styrene copolymer processes. 

Methods have been developed for the analysis of hydrocarbon polymers (e.g. styrene, butadiene and isoprene) by MALDI-TOF-MS, through the attachment of Ag(acac) to matrices of tran5-3-indoleacrylic acid or l,4-bis(2-(5-phenyloxazolyl))benzene . SUver-cationized molecular ions were produced for polymers of styrene, butadiene and isoprene up to mass 125,000 Da. For lower-mass styrene polymers, the resolved oligomer molecular ions provide information concerning the end group. This technique permits the analysis of many commercially important materials such as acrylonitrile-butadiene-styrene (ABS), styrene-acrylonitrile, styrene-methyl methacrylate and styrene-isoprene copolymers. The use of the salts of transition metals other than Ag, Cu or Pd as the cationizing agents fails to cationize polystyrenes in MALDI. The ability of MALDI to reduce metals to the oxidation state 4-1 is critically important to polystyrene cationization, as without this reduction MALDI tends to fail to form polystyrene-metal cations. Cu(acac)2 was used for the verification of the above . 

Craze formation is a dominant mechanism in the toughening of glassy polymers by elastomers in polyblends. Examples are high-impact polystyrene (HIPS), impact poly(vinyl chloride), and ABS (acrylonitrile-butadiene-styrene) polymers. Polystyrene and styrene-acrylonitrile (SAN) copolymers fracture at strains of 10 , whereas rubber-modified grades of these polymers (e.g., HIPS and ABS) form many crazes before breaking at strains around 0.5. Rubbery particles in... 

Graft copolymers are important as elastomeric (e.g., styrene-butadiene rubber (SBR)) and high-impact polymers (e.g., high-impact polystyrene and acrylonitrile-butadiene-styrene (ABS)). 

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