Polystyrene solution carbon tetrachloride

Styrene is a colorless Hquid with an aromatic odor. Important physical properties of styrene are shown in Table 1 (1). Styrene is infinitely soluble in acetone, carbon tetrachloride, benzene, ether, / -heptane, and ethanol. Nearly all of the commercial styrene is consumed in polymerization and copolymerization processes. Common methods in plastics technology such as mass, suspension, solution, and emulsion polymerization can be used to manufacture polystyrene and styrene copolymers with different physical characteristics, but processes relating to the first two methods account for most of the styrene polymers currendy (ca 1996) being manufactured (2—8). Polymerization generally takes place by free-radical reactions initiated thermally or catalyticaHy. Polymerization occurs slowly even at ambient temperatures. It can be retarded by inhibitors. 

Reaction Scheme of CMS Resists. The transient absorption spectrum shown in Figure 6 and observed for irradiated CMS films is mainly composed of two components as based on pulse radiolysis data of solid films of CMS and polystyrene, and CMS and polystyrene solutions in cyclohexane, chloroform, and carbon tetrachloride. An absorption with a maxima at 320 nm and 500 nm as due to the charge transfer radical-complex of the phenyl ring of CMS and chlorine atom (see Figure 14) and an absorption with maxima at 312 and 324 nm is due to benzyl type radicals (see Figure 11). 

Almost all electrophilic substitutions known to proceed in solution with isopropylbenzene can also be performed with polystyrene, using solvents such as nitrobenzene, carbon disulfide, or carbon tetrachloride. These substitutions include bromination [42], nitration [43,44], sulfonylation, Friedel-Crafts acylations [45 49], and alkylations... 

Linden and Leemput10 measured p, 0, and T for polystyrene adsorbed on the Aerosil 130 silica from cyclohexane and carbon tetrachloride solutions at 35 °C as a function of molecular weight. To minimize the complexity due to molecular weight... 

The dynamic viscoelasticity and the thermal behaviour of films of Thermoelastic 125 cast from solutions in four solvents - toluene (T), carbon tetrachloride (C), ethyl acetate (E), and methyl ethyl ketone (M) — have been studied by Miyamato133 The mechanical loss tangent (tan 8) and the storage modulus E dependences exhibit two transitions at —70 °C and 100 °C which have been attributed to onset of motion of polybutadiene and polystyrene segments, respectively. The heights of the polybutadiene peaks on tan 6 curves decrease in the order C > T > E > M, while for polystyrene the order is reversed C < T < E < M. These phenomena have been related to the magnitude of phase separation of the polystyrene and polybutadiene blocks. 

Couzis, A., Gulari, E. (1994) Adsorption kinetics of polystyrene onto germanium from a carbon tetrachloride solution, Macromolecules 27(13), 3580-3588. 

In cyclohexane geminate recombination occurs very efficiently and the observation of polymer ions is rather difficult [57, 58]. However, when the electron scavenger such as chloroform and carbon tetrachloride was added to the solution of polystyrene in cyclohexane, a weak, broad absorption band with a maximum at lOOOnm due to dimer cation of benzene was observed. The dimer cation radical might be produced by the hole migration, along the polymer chain, from a radical cation to a site suitable for the dimer-cation formation [59]. 

Fig. 3. NMR spectra of (a) cumene (10% solution in carbon tetrac loride) and (6) polystyrene Pn 500, 15% solution in carbon tetrachloride)...

Fig. 9. NMR spectra of 10% carbon tetrachloride solutions of polystyrene of very low molecular weight calculated number average degree of polymerization is (a) 20 (6) 10 and (c) 5...

Odajima (20) has independently reported and commented on the NMR spectrum of polystyrene in carbon tetrachloride solution. Unfortunately, the peaks observed were wrongly assigned. 

Linear soluble polystyrene-supported triphenylphosphine/carbon tetrachloride has been used as a condensing agent for the peptide ntiiesis in homogeneous solution After the desired condensation, the polymer is precipitated quantitatively and removed by filtration. The efficiency of this technique has been demonstrated by the preparation of several dipeptide derivatives in 84-95% yields. 

Hradil et al. [395, 396] prepared a set of composite membranes containing fine particles of conventional macroporous resins or hypercrosslinked polystyrene adsorbing materials in films of poly(2,6-dimethyl-l,4-phenylene oxide) as a binder. Hypercrosslinked resins were either a commercial product, Lewatit EP63 (Bayer AG), or were obtained by crosslinking (i) a macroporous styrene—divinylbenzene (DVB) copolymer with carbon tetrachloride (Hyp-St—DVB) or (ii) a finear polystyrene with monochlorodi-methyl ether. In the latter case the reaction of bridging was conducted in a pretty diluted ethylene dichloride solution at stirring, which resulted in obtaining a particulate (1—5 pm) product. 

Polystyrene films were prepared by doubly dipping the substrate—a silicon wafer previously cleaned by pure solvents and etched by hydrogen fluoride—into solutions of 1 gL of pure polystyrene in carbon tetrachloride (spectroscopic grade) and allowing the solvent to evaporate. Thickness of the films thus obtained was estimated to be of the order of 100 A by elastic recoil diffiision analysis (ERDA) measurements [122]. 

For semi-dilute solutions of polystyrene in carbon tetrachloride and deuter-... 

Figure 5.13. The amount of polystyrene adsorbed on to Si02 from cyclohexane at 35 °C (circles) and carbon tetrachloride (triangles), as a function of the degree of polymerisation. Lines are self-consistent mean-field calculations using % = 0.5 for cyclohexane and % =0.4 for carbon tetrachloride solutions. Adapted from van der...

A common feature of all styrene plastics is their resistance to an aqueous media such as salt solutions, acids of medium concentration and alkalis. Aliphatic hydrocarbons, for example, heptane and cyclohexane, readily attack PS and TPS but do not affect SAN and ABS. Carbon tetrachloride (CCI4) attacks SAN and ABS only slowly but quickly attacks PS and TPS. Resistance to CCI4 may be used to distinguish between PS and SAN. In the case of the polystyrene, when it is immersed in the CCI4 it immediately becomes sticky whilst SAN is relatively unaffected. Alternatively if a few drops of CCI4 are put into a test tube containing PS or SAN. In the case of the PS, the liquid becomes milky in a short period of time whereas with SAN it remains colorless. 

Alp. 100 solution of polystyrene in carbon tetrachloride is freeze-dried. 

Polystyrene was employed in GLC as solvent for the following solutes benzene, cyclohexane and n-pentane [3], n-hexadecane [88], normal, branched and cyclic alkanes, single and dinuelear aromatic hydrocarbons, ds- and ira -decaline [60], n-octane, n-decane, chloroform, carbon tetrachloride, benzene, nitromethane and ethanol [89], methanol, carbon sulphide, 1,2,4-trimethylbenzene, pentane and tri-isopropylbenzene [90]. Some of the polymers-solute systems mentioned are encountered in other contributions [31, 43, 91 — 93]. The results differ in respect of y" and Xj2 values and their temperature variation. The possible somces... 

Patticini [8] has described an IR method for the determination of 1-8% of mineral oil in polystyrene (PS). In this method the PS sample is dissolved in carbon tetrachloride, together with known mineral oil standards. The solutions are evaluated by measurements made between 3100 and 3000 cm using a spectral subtraction technique. 

Benzophenone was used as photosensitizer in a study of the photo-decomposition of benzene solutions of polystyrene and poly(a-methyl styrene). Laser photolysis (A 265 nm) of poIy(a-methyl styrene) in chlorofonn and carbon tetrachloride proceeded by attack of solvent radicals in the polymer molecules resulting in main chain cleavage. " A series of papers have been devoted to the study of the photo-induced decomposition of poly(a-methyl styrene) in benzene solutions, using a,a -bisisobutyronitrile, benzophenone, and triphenyl-methyl cations as sensitizers. Spin-trapping techniques were used to detect transient radicals formed during benzophenone-sensitized degradation of poly-(a-methyl styrene). The rate constant for intramolecular reaction of the macroradical was estimated. 

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