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Poly oxyethylene ethylene

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]. [Pg.2416]

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. [Pg.22]

Poly(oxyethylene) resins. See Poly(ethylene oxide) polymers. [Pg.791]

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). [Pg.254]

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. [Pg.795]

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]. [Pg.728]

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. ... [Pg.25]

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... 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...
Poly(oxyethylenej/poly(oxypropylene) copolymers The micellization of water-soluble poly(oxyethylene)-poly(oxypropylene)-poly (oxyethylene), also known as poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) triblock copolymers, has been extensively studied due to the industrial applications of these materials arising from... [Pg.139]

From the field desorption mass spectra of standard samples, a table for identification of poly(oxyethylene) alkylphenyl ethers and determination of the degree of polymerisation of ethylene oxide was constructed as shown in Table 6.1 n is the number of alkyl carbon atoms and m is the degree of polymerisation of ethylene oxide. When the field desorption mass spectrum having a peak pattern with the difference of 44m/z was obtained such as the peaks at 484, 528, 572, 616 and 660m/z, Table 6.1 would show that those peaks are due to poly(oxyethylene) nonylphenyl ethers with the degree of polymerisation of 6-10 of ethylene oxide. Table 6.2 also shows the identification of poly(oxyethylene) dialkylphenyl ethers and determination of the degree of polymerisation of ethylene oxide based on calculations of the molecular weight. [Pg.182]

We have developed new reaction systems based on colloidal dispersions [23, 24], namely highly concentrated water-in-oil (gel) emulsions, which could overcome most of the disadvantages of the aqueoussolvent mixtures such as inactivation of the aldolase and incomplete aldehyde solubilization in the medium. These emulsions are characterized by volume fractions of dispersed phase higher than 0.73 [25] therefore, the droplets are deformed and/or polydisperse, separated by a thin film of continuous phase. Water-in-oil gel emulsions of water/Ci4E4/oil 90/4/6 wt%, where C14E4 is a technical grade poly(oxyethylene) tetradecyl ether surfactant, with an average of four moles of ethylene oxide per surfactant molecule and oil can be octane, decane, dodecane, tetradecane, hexadecane, or squalane, were typically chosen as reaction media [23, 26]. [Pg.301]

SYNS ETHYLENE OXIDE and PROPYLENE OXIDE BLOCK POLYMER PROPYLENE OXIDE and ETHYLENE OXIDE BLOCK POLYMER tt-HYDRO-W-H T)ROXY-POLY(OXYRTmT,ENE)-POLY(OXYPROPYL-ENE)(51-57 MOLES)POLY(OXYETHYLENE) BLOCK POLYMER... [Pg.1138]

UCON is a random copolymer of ethylene oxide (EO) and propylene oxide (PO) and can be considered as a synthetic oil. POE is poly(oxyethylene), which is a homopolymer of EO. Random EO-PO copolymers are typical of synthetic oils used as lubricants in textile processing (53, 54). PLURONICS (BASE) are block copolymers of EO and PO. Both of these copolymers can be produced with viscosities ranging from that of a thin oil to that of a thick paste. Oils of appropriate viscosity give hydrodynamic lubrication in the high-speed spinning of synthetic fibers. The hydrophile-lipophile balance (HLB) in these polymers can be varied, by changing the EO-PO composition, to suit the aqueous solubility requirements. [Pg.3342]

Poly(oxyethylene) units can be introduced by using commercially available polyethylene oxide)s and poly (ethylene glycol) s via esterification of the terminal hydroxyl groups with appropriate acyl halides. Various AB- (B-123 and B-124) and ABA-type (B-125 and B-126) block copolymers were thus prepared,171 327 405 408 along with a polypropylene oxide)-based version (B-l27).404 The polymer coupling be-... [Pg.496]

A polymer molecule in its simplest form is a linear chain of covalently bonded identical monomers. A very simple synthetic polymer is polyethylene, which is obtained by linear polymerization of ethylene, CH2CH2, yielding [—CH2—]n, i.e., a very long paraffin chain. Another simple example is poly(oxyethylene), [—O—CH2—CH2—] . n is the degree of polymerization, and it can be very high, up to about a million. The monomers may have one or more reactive side groups. [Pg.156]


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