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Toluene-soluble polymers

Organic peroxide are used to polymerise the esters by solvent or emulsion polymerisation. They form tough and pliable film. They are also used as plasticising agents for vinyl polymers. The polymer is soluble in benzene, toluene, chloroform, ethylene dichloride, ethyl acetate, etc. [Pg.179]

Pu reported the synthesis of axially chiral-conjugated polymer 82 bearing a chiral binaphthyl moiety in the main chain by the cross-coupling polymerization of chiral bifunctional boronic acid 80 with dibromide 81 (Equation (39)). The polymer is soluble in common organic solvents, such as THE, benzene, toluene, pyridine, chlorobenzene, dichloromethane, chloroform, and 1,2-dichloroethane. The polymer composed of racemic 80 was also synthesized, and the difference of characteristics was examined. Optically active polymer 82 was shown to enhance fluorescence quantum yield up to = 0.8 compared with the racemic 82 ( = 0.5). Morphologies of the optically active and racemic polymers were also compared with a systematic atomic-force microscopy (AEM). [Pg.666]

Electron microscopy of the final latex of the experiments given in Table I showed almost no new nucleation. The particle size distributions were narrow and indicated no noticeable coagulation as well. New nucleation would lead to increased rates whereas coagulation would have the opposite effect. Any decrease in the rate therefore must be due to a decrease in [m], if we assume n to be constant. We therefore determined the tofuene/polymer ratio in the seed latex in the absence and presence of the various additives. Toluene was chosen as the solvent, because it is similar to styrene and allows the measurement of equilibrium solubilities without the risk of polymerization. Table II gives the experimental values of the toluene solubility in the seed as a function of time. The results indicate that the swelling is nearly complete within 5 to 10 min. [Pg.359]

When the polymers were analyzed for their content of homopolymer, it was found that the acrylonitrile polymer is soluble in chlorobenzene and the vinyl chloride polymer in toluene. Since chlorobenzene is unable to dissolve polyacrylonitrile and toluene cannot dissolve poly (vinyl chloride), it must be assumed that no homopolymer has been formed. This has been verified by fractionations. It is possible to extract with methanol from the vinyl acetate polymer 33% of a substantially pure polyvinyl acetate with a vinyl acetate content of 95%. Hence, acrylo-... [Pg.500]

All of the polymers were soluble in hot tetrachloroethane, but, unexpectedly, the polyformal of the tetramethylcyclobutanediol isomer mixture was also soluble in chloroform and in hot toluene. [Pg.207]

Polyfluorene was first synthesized by Fukuda et al. via oxidative polymerization of huorene monomers using ferric chloride as a catalyst.2,11 Both mono- and dialkyl-substituted polyfluorenes were synthesized. Figure 10.1 shows the repeat unit of poly(9,9/-dialkyl-huorene-2,7-diyl). The polymers are soluble in common solvents such as chloroform, dichloromethane, and toluene. Figure 10.2 shows the absorption and fluorescence spectra of a solution of poly(9,9/-dihexylfluorene-2,7-diyl) (PDHF) in chloroform.11 The onset of the tt-tt absorption is at 420 nm, rising to a peak at 380 nm, yielding an optical gap of 2.95 eV. The fluorescence spectrum contains vibronic peaks at 417 and 440 nm and a shoulder at 470 480 nm. [Pg.266]

Properties Liquid. Bp 68C, fp -23C, refr index 1.474, d 1.22, dipole moment 1.98 (D). The polymer is soluble in toluene, chloroform, and methyl ethyl ketone and has dielectric constant of 2.56. Nonflammable. [Pg.1275]

Similarly to the zirconocene/MAO catalysts, the activity of the Idemitsu catalyst systems is poor when the whole catalyst system (catalyst-i-co-catalyst) is taken into account. In the very best example (in terms of catalyst activity and polymer yield) nickel bis (acetylacetonate) was used in combination with MAO (molar ratio 1 200) to homopolymerize norbornene in toluene at 50 °C for 4 h affording a 70% conversion into high molecular weight (M 2.2x10 ), toluene-soluble poly-(norbornene). The ratio of norbornene to nickel was 20000 1 and the ratio of norbornene to aluminum was only 100 1. Thus, while the yield of polymer is high based on the nickel catalyst (25 700 g per g nickel), the yield based on aluminum is very poor (260 g per g aluminum or about 120 g per g MAO). It can readily be estimated that the cost of the MAO activator alone would add significantly to the cost of the polymer, as well as requiring costly removal of catalyst residues from the polymer. [Pg.106]

The catalyst solution(0.05 mL) is added to a dry two-necked round-bottomed flask (100 mL), equipped with a gas inlet, under a continuous steam of nitrogen. The flask is then heated to 55°C. After several minutes, a white solid is deposited and no more solvent is visible. At this stage the siloxane (1.00 g) is added, the flask equipped with a drying tube, and the nitrogen inlet removed and replaced with a stopper. The flask is heated rapidly to 160°C to initiate the polymerization process and the polymerization is allowed to proceed for 3 h, whereupon a highly viscous polymeric oil is formed. The polymer is soluble in benzene and toluene. ... [Pg.89]

Includes several phenyl and benzyl substituted cyclopentenes similar to biphenyl and o-terphenyl in vapor pressure. See Discussion. c See Reference 21. d N.D.—not determined. e Benzene and toluene soluble polymer. [Pg.308]

For ultrafiltration as a unit operation for the separation of polymer-bound soluble catalysts in particular, the recovery process for a rhodium catalyst from the hydroformylation of dicyclopentadiene is an illustrative example (for another detailed example, see Section 7.5) [26, 27]. Toluene can be used as a solvent with the polyaramide membrane employed. TPPTS or also a sulfonated bidentate phosphine with large ammonium counterions, are used as ligands. For efficient recovery, molecular weights of the catalyst of more than 3000 g mofi were required on the membrane used. Separation is performed in two steps [28]. A pilot plant was run successfully over an extended period of time of three months. [Pg.772]

The first route is the intercalation of polymer from solution. The layered host is exfoliated in a solvent, in which the polymer is soluble [water, toluene, etc). The polymer is adsorbed onto the single-layer surfaces and after evaporation of the solvent or a precipitation procedure, the single layers are restacked, trapping the polymer and the hydrated/solvated ionic species [70]. [Pg.889]

The gravure process is typically chosen because of the printing speeds that can be achieved. To transfer ink at high speed, extremely low viscosity is required. Solvents such as toluene, xylene, and alcohols are often used, sometimes in conjunction with water. Fortunately, many organic polymers are soluble in toluene and xylene. The necessary viscosity range is achievable for pure polymers in solution, unlike the... [Pg.1232]

Common solvent technique is based on a solvent system in which the polymer or pre-polymer is soluble and the silicate layers are swellable. The layered silicate is first swollen in a solvent, such as water, chloroform, or toluene. When the polymer and layered silicate solutions are mixed, the polymer chains intercalate and displace the solvent within the interlayer of the silicate. Upon solvent removal, the intercalated structure remains, resulting in the formation of PCN. Polyimide based nanocomposites are made by using a common solvent like dimethyl acetamide (DMAc) [22],... [Pg.329]

Heating N3P3CU at 250 °C in vacuum and by allowing the conversion to proceed only up to 70%, linear poly(dichloro-phosphazene) could be isolated (see Eq. 3.30). This polymer was soluble in a number of organic solvents such as benzene, toluene, tetrahydrofuran etc., to form clear viscous solutions. [Pg.113]

PE would have a low solubility even in hot toluene. In the case of styrene-butadiene copolymer, the uncrosslinked polymer is soluble in aromatic solvents, whilst the highly crosslinked (gel) fraction is completely insoluble and, indeed, this can be used as the basis of a method for separating gel from uncrosslinked polymer. Copolymers usually dissolve in a greater number of solvents than homopolymers. Thus, whilst PVC is only slightly soluble in acetone or methylene chloride, its copolymers with vinyl acetate or acrylates dissolve easily. [Pg.71]

An example of adsorption of this kind is the adsorption occurring at the oil-water interface. The driving force for adsorption in this case is the minimization of the interfacial tension between the two interfaces. Typically, random copolymers or block copolymers, in which the monomeric imits are preferentially solvated in either of the two phases, adsorb readily at the interface. In the case of homopolymers, adsorption occurs either if the polymer is soluble in both the phases or if the polymer has functional groups that can reduce the interfacial tension. Thus, both polyCethylene oxide) and poly(methyl methaciylate) readily adsorb at the toluene-water interface. The former is soluble in both the phases while the latter has polar side groups that effectively screen the interactions between toluene and water. However, because of its hydrophobic nature polyst3U ene does not adsorb at the same interface (50). [Pg.397]


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See also in sourсe #XX -- [ Pg.194 ]




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Polymers solubility

Solubility toluene

Soluble polymers

Toluene solubles

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