Styrene-butadiene casting

Figure 25.8 Silane treatment of fillers in a styrene-butadiene casting.

At least a monolayer of silane is needed on the filler surface. In practice, about 1% silane is applied to a filler with a particle size of 1 mp, enough for several monolayers. Higher surface-area fillers require higher levels of the coupling agent. Fig. 25.8 shows the effect of the level of silane treatment with several different fillers on the flexural strength of a styrene-butadiene casting. 

Wang and Chen [41] studied the compatibility problems of incompatible NBR-PVC blends. Poly(vinyl-idene chloride-covinyl chloride) is reported to act as an efficient interfacial agent. Blends of PVC, NBR, and the copolymer were prepared by the solution casting technique using THE as a solvent. Improvement in mechanical properties can be achieved in NBR-PVC blend by the addition of different types of rubbers [42]. Different rubbers include NR, styrene butadiene (SBR) and butadiene (BR). Replacement of a few percent of NBR by other rubbers will improve the mechanical properties and at the same time reduce the cost of the blend. 

Concrete Styrene-butadiene copolymer latex additions on centrifugally cast concrete [271]... 

The use of lightly crosslinked polymers did result in hydrophilic surfaces (contact angle 50°, c-PI, 0.2 M PhTD). However, the surfaces displayed severe cracking after 5 days. Although qualitatively they appeared to remain hydrophilic, reliable contact angle measurements on these surfaces were impossible. Also, the use of a styrene-butadiene-styrene triblock copolymer thermoplastic elastomer did not show improved permanence of the hydrophilicity over other polydienes treated with PhTD. The block copolymer film was cast from toluene, and transmission electron microscopy showed that the continuous phase was the polybutadiene portion of the copolymer. Both polystyrene and polybutadiene domains are present at the surface. This would probably limit the maximum hydrophilicity obtainable since the RTD reagents are not expected to modify the polystyrene domains. 

Miyaki and Fujimoto and co-workers [16,17] have obtained an even finer distribution of fixed charge groups by casting films from multicomponent block copolymers such as poly(isoprene- >-styrene- >-butadiene- >-(4-vinyl benzyl)dime-thylamine- Msoprene). These films show a very regular domain structure with a 200-500 A spacing. After casting the polymer film, the (4-vinyl benzyl) dimethy-lamine blocks were quatemarized with methyl iodide vapor, and the styrene blocks were sulfonated with chlorosulfuric acid. 

Figure 6. Electron micrograph of diblock copolymer of styrene and butadiene cast from xylene (courtesy of M. Hoffman)...

Poly styrene-butadiene-styrene (Casting solvent Methyl Ethyl ketone) 2.020 2.87 19 Mw= 124000... 

Djermouni, B., Ache, H.J. (1980) Effect of casting solvent on the properties of styrene-butadiene-styrene block copolymers studied by positron annihilation techniques . Macromolecules, 13,168. 

Kraton 1101 (styrene-butadiene-styrene) and Kraton 4609 (styrene-ethylene-butylene-styrene) were obtained from Shell Chemical Co. (8). The polymers were purifed by dissolving in toluene and precipitating in methanol. IR spectra were obtained using a Perkin-Elmer Model 299B spectrophotometer. Electron micrographs were taken using a Phillips EM 400T instrument. Samples for transmission electron microscopes were either microtomed or casted from toluene. 

FIGURE 13.5 TEM of spherical butadiene domains in SBS (80% styrene) film cast from toluene. The same patterns were observed in both normal and parallel sections, confirming the periodicity of butadiene domains (from Matsuo, 1968). 

Figure 4.7. Intensity of scattering, corrected for infinite slits, against scattering angle (26) for a solvent-cast film of triblock polymer, styrene-butadiene-styrene, having segment molecular weights of 21,100, 63,400, and 21,100 g/mol. (McIntyre and Campos-Lopez, 1970.)...

While the equilibrium thermodynamic approaches of Meier (1969,1970, 1971) and Inoue et al (1970a,h) predict that particular compositions will have particular fine structures, several investigators have shown that materials cast from different solvents and subsequently dried differ from each other and from materials prepared from the melt. As an example, let us examine the effects of the following solvents on a typical styrene-butadiene-styrene block copolymer benzene/heptane 90/10 tetrahydro-furan/methyl ethyl ketone 90/10, and carbon tetrachloride (Beecher et al, 1969). The particular compositions were chosen to give selective solvating behavior. While benzene dissolves both blocks, the heptane component, which evaporates last, swells only the butadiene block. Tetrahydrofuran is also a mutual solvent it evaporates first, leaving methyl ethyl ketone, which swells only the polystyrene block. Pure carbon tetrachloride is a mutual solvent. (Examples of swelling crystalline block copolymers are considered in Chapter 6.)... 

A series of composites of polystyrene (PS) and block poly(styrene-butadiene) (SBS) prepared by extrusion blending in the injection screw and injection moulding were studied by Fourier transform infrared (FTIR) analysis. Moulded samples were then dissolved and cast as a film and again studied using FTIR, with higher levels of miscibility noted than on the original moulding. SBS content of the samples was between 20 and 80 percent, with studies also completed on the pure polymers. Differences observed from simulated spectra of the polymer composites were explained by interactions between the two polymers due to partial miscibility. Corroboration of results was provided by calorimetry studies. 16 refs. 

As part of a larger project on styrene-butadiene-styrene (SBS) copolymers (14), in which a variety of thermal and physical characteristics were studied, we report here our investigation of linear dynamic properties for which— by definition—the microstructure is unaltered during testing. A variety of sample casting solvents is employed. 

Poly styrene-butadiene). SBR-5362 To 143 g of emulsion were added 8.3 g of a zinc oxide dispersion, 3.7 g of a sulfur dispersion, 3.1 g of a butylated bisphenol A dispersion, and 2 g of a 50% by weight water solution of zinc dibutyl dithiocarbamate. The mixture was stirred, films cast, dried, and cured as above. The crosslinking mechanism again is the usual vulcanization. SBR-880 No additives were necessary since the material was self-crosslinking and is supplied with all necessary stabilizers. Films were cast, dried, and cured as above. 

Fig. 3.65. Effect of photo-oxidation on the IR spectra of poly(acrylonitrile-co-butadiene-co-styrene) (ABS) cast films = diminishing bands and I = growing bands. (Reprinted with permission from [1936], Pergamon Press Ltd, Oxford, England.)...

Block copolymers are also cast or spin coated for evaluation by a range of techniques, and these are discussed later in this chapter (see Section 5.3.4.6). Chen and Thomas [113] used force modulation microscopy (FMM), a SPM technique that measures relative elasticity across a surface, to study the block copolymer morphology of roll cast and spin coated films. Three model samples were investigated unannealed poly(styrene-butadiene-styrene) triblock copolymer, fabricated from solution using roll casting, cut perpendicular to the oriented cylinders with a razor blade annealed and unannealed poly(styrene-h-methyl methacrylate diblock copolymer spin coated from solution and an ultrathin film of a rod-coil diblock copolymer cast from a dilute solution onto a carbon coated mica sheet. Triblock copolymers were strained in tension using a copper grid as support and... 

Thermoset Phenolic Sheet, Paper Reinforced Adhesive Coated, Paper-Backed, Plastic Sheet Thermosetting Resins Cast from Monomers Sheet and Rods Scribe-Coated Plastic Sheet Tracing, Glazed and Matte Finish Plastic Sheet FEP Fluorocarbon Extruded Sheet and Film Polyethylene, Laminated, Nylon Reinforced Sheet Styrene-Butadiene Sheet... 

Electron microscopy (59, 60) is not as generally applicable because sample preparation is sometimes difficult. For the butadiene-styrene copolymers used here, contrasting of the butadiene phase with 0s04 is particularly suitable (41). Thin films, several tenths of a micron thick, are cast from dilute solutions and placed in the vapor of an aqueous 0s04 solution. A similar process is followed for thin sections of macroscopic samples. If the morphological structure of these films in planes normal to the film surface is of interest, such films must be embedded before cutting in a material of similar hardness which does not swell or dissolve the sample to be investigated. 

ABA ABS ABS-PC ABS-PVC ACM ACS AES AMMA AN APET APP ASA BR BS CA CAB CAP CN CP CPE CPET CPP CPVC CR CTA DAM DAP DMT ECTFE EEA EMA EMAA EMAC EMPP EnBA EP EPM ESI EVA(C) EVOH FEP HDI HDPE HIPS HMDI IPI LDPE LLDPE MBS Acrylonitrile-butadiene-acrylate Acrylonitrile-butadiene-styrene copolymer Acrylonitrile-butadiene-styrene-polycarbonate alloy Acrylonitrile-butadiene-styrene-poly(vinyl chloride) alloy Acrylic acid ester rubber Acrylonitrile-chlorinated pe-styrene Acrylonitrile-ethylene-propylene-styrene Acrylonitrile-methyl methacrylate Acrylonitrile Amorphous polyethylene terephthalate Atactic polypropylene Acrylic-styrene-acrylonitrile Butadiene rubber Butadiene styrene rubber Cellulose acetate Cellulose acetate-butyrate Cellulose acetate-propionate Cellulose nitrate Cellulose propionate Chlorinated polyethylene Crystalline polyethylene terephthalate Cast polypropylene Chlorinated polyvinyl chloride Chloroprene rubber Cellulose triacetate Diallyl maleate Diallyl phthalate Terephthalic acid, dimethyl ester Ethylene-chlorotrifluoroethylene copolymer Ethylene-ethyl acrylate Ethylene-methyl acrylate Ethylene methacrylic acid Ethylene-methyl acrylate copolymer Elastomer modified polypropylene Ethylene normal butyl acrylate Epoxy resin, also ethylene-propylene Ethylene-propylene rubber Ethylene-styrene copolymers Polyethylene-vinyl acetate Polyethylene-vinyl alcohol copolymers Fluorinated ethylene-propylene copolymers Hexamethylene diisocyanate High-density polyethylene High-impact polystyrene Diisocyanato dicyclohexylmethane Isophorone diisocyanate Low-density polyethylene Linear low-density polyethylene Methacrylate-butadiene-styrene... 

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