Sulfoxide polymer

SAK Sakurai, K., Ochi, K., Norisuye, T., and Fujita, H., Stiff-chain behavior of poly(terephthalamide-p-benzohydrazide) in dimethyl sulfoxide, Polym. J., 16, 559, 1984. 

These three polymerization reactions can be summarized as shown in Scheme 1, where Q = S, S2, or SO. Q bridges the p-diketones from adjacent units in the polymer chains. The corresponding sulfone polymer can be synthesized by the oxidation of the sulfoxide polymer with hydrogen peroxide. 

PolyI(S-leucinato-, 0) cobalt(III)-u-[3,3 -sulfonebis(2,4-pentanedio-nato-0,0 )]I.—Initially, 0.10 mL hydrogen peroxide was added dropwise to 0.0603 g fractionated sulfoxide polymer in 10 mL acetonitrile with vigorous stirring. The mixture was heated to 40 C and stirred for 24 h. The solvent was removed in vacuo at 40°C, and the sample was then dried in vacuo at lOO C. 

The cobalt sulfone polymer was prepared by hydrogen peroxide oxidation of the corresponding sulfoxide polymer. 

Figure 3. Relative quantum yield of trans-cis photoisomerization of polymer containing azo- benzene residues in its chain backbone and of its low molecular weight analog in mixtures of poly (isophorone diamine isophthalamide) and dimethyl-sulfoxide. Polymer (P-IIi) Copolyamide of iso-phthalic acid with isophorone diamine containing 1.5 mole % 4,4 -azodianiline. Analog (A-II) ...

Dimethylformamide [68-12-2] (DME) and dimethyl sulfoxide [67-68-5] (DMSO) are the most commonly used commercial organic solvents, although polymerizations ia y-butyrolactoae, ethyleae carboaate, and dimethyl acetamide [127-19-5] (DMAC) are reported ia the hterature. Examples of suitable inorganic salts are aqueous solutioas of ziac chloride and aqueous sodium thiocyanate solutions. The homogeneous solution polymerization of acrylonitrile foUows the conventional kinetic scheme developed for vinyl monomers (12) (see Polymers). 

Trilialophenols can be converted to poly(dihaloph.enylene oxide)s by a reaction that resembles radical-initiated displacement polymerization. In one procedure, either a copper or silver complex of the phenol is heated to produce a branched product (50). In another procedure, a catalytic quantity of an oxidizing agent and the dry sodium salt in dimethyl sulfoxide produces linear poly(2,6-dichloro-l,4-polyphenylene oxide) (51). The polymer can also be prepared by direct oxidation with a copper—amine catalyst, although branching in the ortho positions is indicated by chlorine analyses (52). 

The first aromatic sulfone polymer produced commercially was introduced as Bakelite polysulfone but now is sold by Union Carbide under the trade name Udel. It is made by reaction of the disodium salt of bisphenol A (BPA) with 4,4 -dichIorodiphenyl sulfone in a mixed solvent of chlorobenzene and dimethyl sulfoxide (eq. 12). 

I itro-DisplacementPolymerization. The facile nucleophilic displacement of a nitro group on a phthalimide by an oxyanion has been used to prepare polyetherimides by heating bisphenoxides with bisnitrophthalimides (91). For example with 4,4 -dinitro monomers, a polymer with the Ultem backbone is prepared as follows (92). Because of the high reactivity of the nitro phthalimides, the polymerkation can be carried out at temperatures below 75°C. Relative reactivities are nitro compounds over halogens, Ai-aryl imides over A/-alkyl imides, and 3-substituents over 4-substituents. Solvents are usually dipolar aprotic Hquids such as dimethyl sulfoxide, and sometimes an aromatic Hquid is used, in addition. 

Solvent for Displacement Reactions. As the most polar of the common aprotic solvents, DMSO is a favored solvent for displacement reactions because of its high dielectric constant and because anions are less solvated in it (87). Rates for these reactions are sometimes a thousand times faster in DMSO than in alcohols. Suitable nucleophiles include acetyUde ion, alkoxide ion, hydroxide ion, azide ion, carbanions, carboxylate ions, cyanide ion, hahde ions, mercaptide ions, phenoxide ions, nitrite ions, and thiocyanate ions (31). Rates of displacement by amides or amines are also greater in DMSO than in alcohol or aqueous solutions. Dimethyl sulfoxide is used as the reaction solvent in the manufacture of high performance, polyaryl ether polymers by reaction of bis(4,4 -chlorophenyl) sulfone with the disodium salts of dihydroxyphenols, eg, bisphenol A or 4,4 -sulfonylbisphenol (88). These and related reactions are made more economical by efficient recycling of DMSO (89). Nucleophilic displacement of activated aromatic nitro groups with aryloxy anion in DMSO is a versatile and useful reaction for the synthesis of aromatic ethers and polyethers (90). 

Glean-Up Solvent. Dimethyl sulfoxide is used to remove urethane polymers and other difficult-to-solvate materials from processing equipment. 

VV -values for bromoform and pyrrole, acidic liquids, against poly(vinyl chloride), an acidic polymer, and dimethyl sulfoxide, a predominantly basic liquid, against polyfmethyl methacrylate), a basic polymer, but large values for the acidic liquids against PMMA and the basic liquid against PVC. 2-Iodoethanol, a bifunctional liquid, showed appreciable -values with both polymers. Despite these results in line with expectations, other results based on wettability measurements are not so clear-cut. For example, Vrbanac [94] found significant apparent acid-base interactions of various aromatic liquids against poly(ethylene), presumably a neutral substrate. 

Phenol, the simplest and industrially more important phenolic compound, is a multifunctional monomer when considered as a substrate for oxidative polymerizations, and hence conventional polymerization catalysts afford insoluble macromolecular products with non-controlled structure. Phenol was subjected to oxidative polymerization using HRP or soybean peroxidase (SBP) as catalyst in an aqueous-dioxane mixture, yielding a polymer consisting of phenylene and oxyphenylene units (Scheme 19). The polymer showed low solubility it was partly soluble in DMF and dimethyl sulfoxide (DMSO) and insoluble in other common organic solvents. 

The sulfonylated and acylated PPO presents solubility characteristics which are completely different from those of the parent PPO. Table V presents the solubility of some modified structures compared to those of unmodified PPO. It is very important to note that, after sulfonylation, most of the polymers become soluble in dipolar aprotic solvents like dimethyl sulfoxide (DMSO), N,N— dimethylformamide (DMF) and N,N-dimethylacetamide (DMAC). At the same time it is interesting to mention that, while PPO crystallizes from methylene chloride solution, all the sulfonylated polymers do not crystallize and form indefinitely stable solutions in methylene chloride. Only some of the acetylated polymers become soluble in DMF and DMAC, and none are soluble in DMSO. The polymers acetylated with aliphatic acid chlorides such as propionyl chloride are also soluble in acetone. 

Sulfur(II)-containing compounds possess the reducing activity and react with hydroperoxides and peroxyl radicals [1-5]. They are employed as components of antioxidant additives to lubricants and polymers [30-35]. Denison and Condit [36] were the first to show that dialkyl sulfides are oxidized by hydroperoxides to sulfoxides and then to sulfones... 

Fluorene-[2,5-di(aminoethoxy)benzene] copolymers 370a,b have been synthesized by Huang and coworkers [437,438] as precursors to the first water-soluble cationic PFs 371, 372a-c (Scheme 2.58). Whereas the neutral polymers 370a,b readily dissolve in common organic solvents such as THF, chloroform, toluene, and xylene (but not in dimethyl sulfoxide (DMSO), methanol, or water) their quaternization produces material 371, which is insoluble in chloroform or THF but completely soluble in DMSO, methanol, and water. For... 

Sulfoxide donors have been employed in the glycosylation of soluble and insoluble polymer-supported glycosyl acceptors, and the area has been reviewed [86,283]. 

The solubility is generally improved by the introduction of fluorine atoms into aromatic condensation polymers. Poly(carbonate)s containing hexafluoroisopropylidene units are much more soluble than Bisphenol A poly(carbonate) (3). All of the hexafluoroisopropylidene-unit-containing poly(carbonate)s become soluble in acetone, ethyl acetate, chloroform, and dimethyl sulfoxide (DMSO) in addition to the solvents of Bisphenol A poly(carbonate) (3). Colorless, transparent, and flexible films are prepared from hexafluoroisopropylidene-unit-containing poly(carbonate)s by casting or pressing. 

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