Poly oxyethylene

Several studies have demonstrated the successful incoriDoration of [60]fullerene into polymeric stmctures by following two general concepts (i) in-chain addition, so called pearl necklace type polymers or (ii) on-chain addition pendant polymers. Pendant copolymers emerge predominantly from the controlled mono- and multiple functionalization of the fullerene core with different amine-, azide-, ethylene propylene terjDolymer, polystyrene, poly(oxyethylene) and poly(oxypropylene) precursors [63,64,65,66,62 and 66]. On the other hand, (-CggPd-) polymers of the pearl necklace type were fonned via the periodic linkage of [60]fullerene and Pd monomer units after their initial reaction with thep-xy y ene diradical [69,70 and 71]. 

Alexandridis P, Olsson U and Lindman B 1997 Structural polymorphism of amphiphilic copolymers Six lyotropic liquid crystalline and two solution phases in a poly(oxybutylene)-poly(oxyethylene)-water-xylene system Langmuir 23-34... 

Wanka G, Floffman FI and Ulbrict W 1990 The aggregation behavior of poly-(oxyethylene)-poly(oxypropylene)-poly-(oxyethylene)-block copolymers in aqueous solutions Colloid Polym. Sc/. 268 101-17... 

Those polymers which are the condensation product of two different monomers are named by applying the preceding rules to the repeat unit. For example, the polyester formed by the condensation of ethylene glycol and terephthalic acid is called poly(oxyethylene oxyterphthaloyl) according to the lUPAC system, as well as poly (ethylene terephthalate) or polyethylene terephthalate. 

Poly(oxyethylene) resins. See Poly(ethylene oxide) polymers. 

HydrophobicaHy Modified, Ethoxylated Urethane. HEUR associative thickeners are in effect poly(oxyethylene) polymers that contain terminal hydrophobe units (66). They can be synthesized via esterification with monoacids, tosylation reactions, or direct reaction with monoisocyanates. There are problems associated with aH of the methods of synthesis. The general commercial procedure for their synthesis is by a step-growth addition of... 

The detergent range alcohols and their derivatives have a wide variety of uses ia consumer and iadustrial products either because of surface-active properties, or as a means of iatroduciag a long chain moiety iato a chemical compound. The major use is as surfactants (qv) ia detergents and cleaning products. Only a small amount of the alcohol is used as-is rather most is used as derivatives such as the poly(oxyethylene) ethers and the sulfated ethers, the alkyl sulfates, and the esters of other acids, eg, phosphoric acid and monocarboxyhc and dicarboxyhc acids. Major use areas are given ia Table 11. 

Fully modified yams had smooth, all-skin cross sections, a stmcture made up of numerous small crystaUites of cellulose, and filament strengths around 0.4 N/tex (4.5 gf/den). They were generally known as the Super tire yams. Improved Super yams (0.44—0.53 N/tex (5—6 gf/den)) were made by mixing modifiers, and one of the best combiaations was found to be dimethylamine with poly-(oxyethylene) glycol of about 1500 mol wt (25). Ethoxjlated fatty acid amines have now largely replaced dimethylamine because they are easier to handle and cost less. 

A major pharmaceutical use of poly(oxyethylene) sorbitan fatty acid esters is in the solubilization of the oil-soluble vitamins A and D. In this way, multivitamin preparations can be made which combine both water- and oil-soluble vitamins in a palatable form. 

Sorbitan sesquioleate emulsions of petrolatum and wax are used as ointment vehicles in skin treatment. In topical appHcations, the inclusion of both sorbitan fatty esters and their poly(oxyethylene) derivatives modifies the rate of release and promotes the absorption of antibiotics, antiseptics, local anesthetics, vasoconstrictors, and other medications from suppositories, ointments, and lotions. Poly(oxyethylene(20)) sorbitan monooleate, also known as Polysorbate 80 (USP 23), has been used to promote absorption of ingested fats from the intestine (245). 

Emulsions of fatty- and petroleum-based substances, both oils and waxes, of the o/w type are made by using blends of sorbitan fatty esters and their poly(oxyethylene) derivatives. Mixtures of poly(oxyethylene(20)) sorbitan monostearate (Polysorbate 60) and sorbitan monostearate are typical examples of blends used for lotions and creams. Both sorbitan fatty acid esters and their poly(oxyethylene) derivatives are particularly advantageous in cosmetic uses because of their very low skin irritant properties. Sorbitan fatty ester emulsifiers for w/o emulsions of mineral oil are used in hair preparations of both the lotion and cream type. Poly(oxyethylene(20)) sorbitan monolaurate is useflil in shampoo formulations (see Hairpreparations). Poly(oxyethylene) sorbitan surfactants are also used for solubilization of essential oils in the preparation of colognes and after-shave lotions. 

Polyall lene Oxide Block Copolymers. The higher alkylene oxides derived from propjiene, butylene, styrene (qv), and cyclohexene react with active oxygens in a manner analogous to the reaction of ethylene oxide. Because the hydrophilic oxygen constitutes a smaller proportion of these molecules, the net effect is that the oxides, unlike ethylene oxide, are hydrophobic. The higher oxides are not used commercially as surfactant raw materials except for minor quantities that are employed as chain terminators in polyoxyethylene surfactants to lower the foaming tendency. The hydrophobic nature of propylene oxide units, —CH(CH2)CH20—, has been utilized in several ways in the manufacture of surfactants. Manufacture, properties, and uses of poly(oxyethylene- (9-oxypropylene) have been reviewed (98). 

Poly(Oxyethylene-coOxypropylene) Nonionic Surfactants. A great variety of these surfactants is marketed by BASE Corporation under the Pluronic polyol trademark. The synthesis foUows ... 

Pluronic L62 is a poly(oxyethylene)—poly(oxypropylene)—poly(oxyethylene) copolymer marketed by BASF AG. 

Block copolymers of ethylene oxide and propylene oxide, less hydrophilic than poly(oxyethylene) glycol and more reactive than the propylene oxide polymers, were introduced by Wyandotte Chemical (USA) under the trade name Pluronic. 

Beaded methacrylate polymers, poly(hydroxyethylmethacrylate), Spheron, Separon (29), and poly(glycidylmethacrylate), Eupergin (30,31), are studied extensively at the Czechoslovak Academy of Macromolecular Sciences. An addition to this type of support is poly(oxyethylene-dimethacrylate) (32). Heitz et al. (33) described the preparation of beaded poly(methylacrylates) cross-linked with ethanedimethacrylates. 

Chemical Name Poly (oxyethylene)-poly(oxypropylene)-poly (oxyethylene) Common Name Poloxalene... 

Nitriles react with alcohols in the presence of hydrochloric acid to form iminoester hydrochlorides, which are hydrolyzed to the esters (Pinner synthesis). Heitz and coworkers [21-23] published several fine papers on the polyazoester synthesis from the reaction of a series of poly(oxyethylene) glycol or poly(oxypropylene) glycol and AIBN in the presence of dry hydrochloric acid at 0-5°C according to Pinner synthesis. Condensation reactions of ACPC and dihydroxy terminated poly(oxy-ethylene) glycol yield polyazoesters [24,25]. 

At constant PBT/PTMO composition, when the molar mass of PTMO block is >2000, partial crystallization of the polyether phase leads to copolymer stiffening. The properties of polyesterether TPEs are not dramatically different when PTMO is replaced by polyethers such as poly(oxyethylene) (PEO) or poly(oxypropylene). PEO-based TPEs present higher hydrophilicity, which may be of interest for some applications such as waterproof breathable membranes but which also results in much lower hydrolysis resistance. Changing PBT into a more rigid polymer by using 2,6-naphthalene dicarboxylic acid instead of terephthalic acid results in compounds that exhibit excellent general properties but poorer low-temperature stiffening characteristics. 

M. J. Schwuger, in Interfacial and Performance Properties of Sulfated Poly-oxyethylenated Alcohols (M. J. Rosen, ed.), ACS Symposium Series 253. Structure/ Performance Relationships in Surfactants, American Chemical Society, Washington, D.C., 1984. 

Anionic polymerization of ethylene oxide by living carbanions of polystyrene was first carried out by Szwarc295. A limited number of methods have been reported in the preparation of A-B and A-B-A copolymers in which B was polystyrene and A was poly(oxyethylene)296-298. The actual procedure was to allow ethylene oxide to polymerize in a vacuum system at 70 °C with the polystyrene anion initiated with cumyl potassium in THF299. The yields of pure block copolymers are usually limited to about 80% because homopolymers are formed300. ... 

The mechanism of the polymerization of NCA with tertiary amine is still controversial. Mori and Iwatsuki claim that the true initiator is the primary amino group formed by hydrolysis of the NCA with contaminated water and that tertiary amine forms a complex with the NCA and accelerates the addition reaction37 . Harwood et al. confirmed the propagating carbamate by NMR in polymerization initiated with a strong base37 . The successive addition of NCA to the polymer end catalyzed with a strong base affords an alternative procedure for the synthesis of block copolypeptides. Block copolypeptides of poly(oxyethylene) were prepared by triethyl amine catalyzed polymerization of NCA in the presence of poly(oxyethylene)bis-eMoroformate38 . 

Wanka, G Hoffman, H Ulbricht, W, Phase Diagrams and Aggregation Behavior of Poly (oxyethylene)-Poly(oxypropylene)-Poly(exyethylene) Triblock copolymers in Aqueous Solutions, Macromolecules 27, 4145, 1994. 

Since poly(oxyethylene)-type nonionic surfactants have a capability of facilitating the transfer of cations [51,52], the above interphase complexation may be seen as an example of precomplex formation before the bulk transfer of ions, which is seen when Aq (p is sufficiently positive. The presence of such precomplex formation at the interface, which is detectable voltammetrically [53], may have significance in the rate of complex formation and the selectivity in the bulk facilitated transfer. 

Another example of chemical-potential-driven percolation is in the recent report on the use of simple poly(oxyethylene)alkyl ethers, C, ), as cosurfactants in reverse water, alkane, and AOT microemulsions [27]. While studying temperature-driven percolation, Nazario et al. also examined the effects of added C, ) as cosurfactants, and found that these cosurfactants decreased the temperature threshold for percolation. Based on these collective observations one can conclude that linear alcohols as cosurfactants tend to stiffen the surfactant interface, and that amides and poly(oxyethylene) alkyl ethers as cosurfactants tend to make this interface more flexible and enhance clustering, leading to more facile percolation. 

Synthesis and Characterization of Poly (oxyethylene)-6-poly(pivalolactone)Telechelomer... 

Figure I indicates the approach used to synthesize poly(oxyethylene)-b-poly(pivalolactone) telechelomers. An acetal capped anionic initiator, X (13) polymerizes ethylene oxide (EO) to give 2> a potassium alkoxide of a masked polyether, and this "new" initiator is to be used to polymerize pivalolactone (PVL). Since potassium alkoxides are strong nucleophiles, they can randomly attack at both the carbonyl carbon and the 3-methylene carbon in lactones, (Figure 2) such a random attack would result in a pivalolactone segment containing irregularities. Lenz (15), and Hall (16), and Beaman (17) have investigated PVL polymerization and have shown that the less nucleophilic carboxylate anion is preferable in polymerizing PVL smoothly. The weaker carboxylate anion will attack only at the methylene...

A variety of reagents could be used to carry out such a conversion (18,19). We chose to react the alkoxide ion with succinic anhydride (SA), because the alkoxide ion could be converted quantitatively to the carboxylate ion when excess of SA is used, and also because no side reactions are reported (19). The carboxylate anion, 3, thus formed was used to polymerize PVL giving the masked poly(oxyethylene)-b-po y(pivalolactone) co-polymeric salt, 4. The salt, 4, was converted to the teiechelomer, 5, by acid hydrolysis.. ... 

Figure 3. Apparatus for the synthesis of poly(oxyethylene)-b-poly(pivalolactone) salt, k.

Figure 6. 50 MHz NMR spectrum of the masked poly(oxyethylene)-t -polyfpivalolactone) copoiymeric salt, 4, using attached proton test sequence (CH, CH3, Pos. CH2, C, neg.) in CDCI3 at 25°C.

Okada, T. (1990). Chromatographic oligomer separation of poly(oxyethylenes) on potassium ion-form cation-exchange resin. Anal. Chem. 62(4), 327-331. 

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