Soluble poly

Solubility. Poly(ethylene oxide) is completely soluble in water at room temperature. However, at elevated temperatures (>98° C) the solubiUty decreases. It is also soluble in several organic solvents, particularly chlorinated hydrocarbons (see Water-SOLUBLE polymers). Aromatic hydrocarbons are better solvents for poly(ethylene oxide) at elevated temperatures. SolubiUty characteristics are Hsted in Table 1. 

The kinetics of vinyl acetate emulsion polymeriza tion in the presence of alkyl phenyl ethoxylate surfactants of various chain lengths indicate that part of the emulsion polymerization occurs in the aqueous phase and part in the particles (115). A study of the emulsion polymerization of vinyl acetate in the presence of sodium lauryl sulfate reveals that a water-soluble poly(vinyl acetate)—sodium dodecyl sulfate polyelectrolyte complex forms, and that latex stabihty, polymer hydrolysis, and molecular weight are controlled by this phenomenon (116). 

Solubility. Poly(vinyl alcohol) is only soluble in highly polar solvents, such as water, dimethyl sulfoxide, acetamide, glycols, and dimethylformamide. The solubiUty in water is a function of degree of polymerization (DP) and hydrolysis (Fig. 4). Fully hydrolyzed poly(vinyl alcohol) is only completely soluble in hot to boiling water. However, once in solution, it remains soluble even at room temperature. Partially hydrolyzed grades are soluble at room temperature, although grades with a hydrolysis of 70—80% are only soluble at water temperatures of 10—40°C. Above 40°C, the solution first becomes cloudy (cloud point), followed by precipitation of poly(vinyl alcohol). 

In addition to its water solubility poly(vinyl pyrrolidone) is soluble in a very wide range of materials, including aliphatic halogenated hydrocarbons (methylene dichloride, chloroform), many monohydric and polyhdric alcohols (methanol, ethanol, ethylene glycol), some ketones (acetyl acetone) and lactones (a-butyrolactone), lower aliphatic acids (glacial acetic acid) and the nitro-paraffins. The polymer is also compatible with a wide range of other synthetic polymers, with gums and with plasticisers. 

Baneijee et al. reported a number of soluble poly-imido [134], polyazomethine [135], and polyazoxy phos-phonates [136] by the two phase polycondensation method with or without any phase transfer catalyst. Resulting polymers exhibit high thermal stability and fire retardancy. 

Anionic polyacrylamide was prepared by gamma radiation-initiated copolymerization of acrylamid with sodium acrylate in aqueous solution at optimum conditions for the copolymerization [17]. The copolymerization process produces water-soluble poly (acrylamide-sodium acrylate [pAM-AANa] of high molecular weight [17,54]. 

As has been outlined above, a second, very fruitful synthetic principle for obtaining structurally homogeneous, processable PPP derivatives involves the preparation of soluble PPPs via introduction of solubilizing side groups. The pioneering work here was carried out at the end of the eighties by Schluler, Wegner, et al. [11, 121, who for the first lime prepared soluble poly(2,5-dialkyl-1,4-phenylene)s 6. 

Other coupling reactions were also employed to prepare poly(arylene etherjs. Polymerization of bis(aryloxy) monomers was demonstrated to occur in the presence of an Fe(III) chloride catalyst via a cation radical mechanism (Scholl reaction).134 This reaction also involves carbon-carbon bond formation and has been used to prepare soluble poly(ether sulfone)s, poly(ether ketone)s, and aromatic polyethers. 

At about die same time, die application of the Suzuki coupling, the crosscoupling of boronic acids widi aryl-alkenyl halides in die presence of a base and a catalytic amount of palladium catalyst (Scheme 9.12),16 for step-growth polymerization also appeared. Schliiter et al. reported die synthesis of soluble poly(para-phenylene)s by using the Suzuki coupling condition in 1989 (Scheme 9.13).17 Because aryl-alkenyl boronic acids are readily available and moisture stable, the Suzuki coupling became one of die most commonly used mediods for die synthesis of a variety of polymers.18... 

Water-soluble poly(p-phenylene), 493 Water reducible materials, 237 WAXS. See Wide-angle x-ray spectroscopy (WAXS)... 

In the field of soluble conducting polymers new data have been published on poly(3-alkylthiophenes " l They show that the solubility of undoped polymers increases with increasing chain length of the substituent in the order n-butyl > ethyl methyl. But, on the other hand, it has turned out that in the doped state the electro-chemically synthesized polymers cannot be dissolved in reasonable concentrations In a very recent paper Feldhues et al. have reported that some poly(3-alkoxythio-phenes) electropolymerized under special experimental conditions are completely soluble in dipolar aprotic solvents in both the undoped and doped states. The molecular weights were determined in the undoped state by a combination of gel-permeation chromatography (GPC), mass spectroscopy and UV/VIS spectroscopy. It was established that the usual chain length of soluble poly(3-methoxthythiophene) consists of six monomer units. 

Mere possession of polar functional groups is not, by itself, enough to confer water-solubility. Poly(vinyl alcohol), which is prepared by the hydrolysis of poly (vinyl ethanoate), is only soluble if a few ethanoate groups are left... 

Sanborn, T., Wu, C., Zuckermann, R., and Barron, A. Extreme stability of helices formed by water-soluble poly-7M-sub-stituted glycines (polypeptoids) with alpha-chiral side chains. Biopolymers 2002, 63, 12-20. 

Soluble poly(l-butylperylene) (58) was prepared in very high yields by Anton and Mullen [70] who used the procedure of Taylor [71], which involves the oxidative coupling of bis-Grignard reagents with as-l,4-dichloro-2-butene as an oxidant. The products contain 4,9- and 4,10-perylenylene moieties, are fully soluble and possess average degrees of polymerization of ca. 22. 

With endogeneous pectic polysaccharides as substrates, the pectin methyhransferase activity was measured as radioactivity linked to oxalate-soluble polys x harides after extensive washing of microsomes with IM ethanolic NaCL Figure 2 shows that the rate of methylesterification of pectic substances was maximal on days 4 and 6 these maximum activities were observed within this period in at least five independent ejqjeriments. On the other hand, little activity was noted in young cells before day 2, and in old cells after day 9. In other words during the stationary phase the newly synthesised pectins remained unesterified because of the lack of pectin methyltransferase activity. 

The hydrolytic stability of water soluble poly[N-(4-sulfo-phenyDdimethacrylamide] (PSPDM) was studied at 90 C in aqueous solutions at pH 7, pH 1.2 (0.1M HC1), and pH 12.3 (0.1M NaOH). PSPDM, which possesses predominantly 5-mem-bered ring imides, was prepared by the cyclopolymerization and subsequent sulfonation of N-phenyldimethacrylamide. No detectable PSPDM imide hydrolysis occurred after 30 days at pH 7 or pH 1.2. Under basic conditions, however, complete hydrolysis to amic acid occurred after one day. The resulting Nsubstituted amide was extremely stable to further basic hydrolysis. 

In a continuing study of substituent effects on the spectra of polysilane derivatives, we have succeeded in the preparation of the first soluble poly(diarylsilane) homopolymers. Materials of this type have traditionally proved to be insoluble and intractable. Very recently, West and co-workers have reported the preparation of some soluble copolymers which contain diphenylsilylene units (48,49). 

The same authors proposed an alternative methods for obtaining soluble poly(/i-vinylborazine) homopolymers and poly(styrene-co-B-vinylborazine) copolymers 28 In fact, gentle polymerization conditions in solution at 80°C using Azobisisobutyronitrile (AIBN) (1.6 mol%) as an initiator provided soluble homopolymers. The polymer displays typical Mw and Mn values of —18,000 and 11,000, respectively, whereas an increase in the AIBN concentration results in a decrease in the molecular weight, contrary to what is usually observed in free-radical polymerization. 

Fig. 6. Frechet s water-soluble poly aryl ethereal dendrimer...

Fig. 1 Chemical structure of water-soluble poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate-co-p-vinylphenylboronic acid (PMBV)...

Kirsh YE (1998) Water soluble poly-N-vinylamides synthesis and physicochemical properties. Wiley, Chichester... 

The chiral recognition ability of the insoluble (+)-l was estimated by HPLC using a column packed with small particles of l.25 However, this column showed a poor efficiency because of a low theoretical plate number. This defect was overcome by coating soluble poly(TrMA) with a DP of 50 on macroporous silica gel.26 The 1-coated silica gel had higher resistance against compression and longer lifetime than the CSP of insoluble 1. Moreover, the two 1-based CSPs show quite different chiral recognition for several race-mates, which may be attributed to the different orientation of 1 in bulk and on the surface of the silica gel.27... 

FI Tomozawa, D Braun, SD Phillips, AJ Fleeger, and FI Kroemer, Metal-polymer Schottky barriers on cast films of soluble poly(3-alkylthiophenes), Synth. Met., 22 63-69, 1987. 

Y Yang, Q Pei, and AJ Heeger, Efficient blue polymer light-emitting diodes from a series of soluble poly(paraphenylene)s, J. Appl. Phys., 79 934—939, 1996. 

SV Frolov, M Liess, PA Lane, W Gellermann, ZY Yardeny, M Ozaki, and K Yoshino, Exciton dynamics in soluble poly(p-phenylene-vinylene) towards an ultrafast excitonic switch, Phys. Rev. Lett., 78 4285-4288, 1997. 

B.R. Hsieh, Y. Yu, A.C. van Laeken, and H. Lee, General methodology toward soluble poly (p-phenylene vinylene) derivatives, Macromolecules, 30 8094-8095, 1997. 

S. Hoger, J. McNamara, S. Schricker, and F. Wudl, Novel silicon-substituted, soluble poly(phe-nylene vinylene)s enlargement of the semiconductor bandgap, Chem. Mater., 6 171-173, 1994. 

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