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Ethylene oxide containing copolymers

Ethylene Oxide Containing Copolymers. The following copolymers were placed in a microwave oven for 5 minutes. [Pg.48]

Copolymer IV and ethylene oxide containing copolymers were kindly provided by Mr. G. A. Vincent and Mr. W. D. Frank of Dow Corning Corporation respectively. [Pg.49]

Ethylene Oxide Containing Copolymers 7.8.1 Polyacetal - Ethylene Oxide... [Pg.266]

Fig. 6. Snapshot from a dynamic density functional simulation of the self-organisation of the block copolymer PL64 (containing 30 propylene oxide rmd 26 ethylene oxide units (EO)i3(PO)3o(EO)i3) in 70% aqueous solution. The simulation was carried out during 6250 time steps on a 64 x 64 x 64 grid (courtesy of B.A.C. van Vlimmeren and J.G.E.M. Praaije, Groningen). Fig. 6. Snapshot from a dynamic density functional simulation of the self-organisation of the block copolymer PL64 (containing 30 propylene oxide rmd 26 ethylene oxide units (EO)i3(PO)3o(EO)i3) in 70% aqueous solution. The simulation was carried out during 6250 time steps on a 64 x 64 x 64 grid (courtesy of B.A.C. van Vlimmeren and J.G.E.M. Praaije, Groningen).
The method has severe limitations for systems where gradients on near-atomic scale are important (as in the protein folding process or in bilayer membranes that contain only two molecules in a separated phase), but is extremely powerful for (co)polymer mixtures and solutions [147, 148, 149]. As an example Fig. 6 gives a snapshot in the process of self-organisation of a polypropylene oxide-ethylene oxide copolymer PL64 in aqueous solution on its way from a completely homogeneous initial distribution to a hexagonal structure. [Pg.27]

Chemical Structure and Properties. Homopolymer consists exclusively of repeating oxymethylene units. The copolymer contains alkyhdene units (eg, ethyUdene —CH2—CH2—) randomly distributed along the chain. A variety of end groups may be present in the polymers. Both homopolymer and copolymer may have alkoxy, especially methoxy (CH3 O—), or formate (HCOO—) end groups. Copolymer made with ethylene oxide has 2-hydroxyethoxy end groups. Homopolymer generally has acetate end groups. [Pg.57]

Two of the perfluoropolyether fluid stmctures yet to be commercialized are interesting. The first stmcture is a strictly alternating copolymer of ethylene oxide and methylene oxide, which has the longest Hquid range of any molecule containing carbon (40). The second stmcture is the perfluoromethylene oxide polyether which has low temperature Hquid properties down to —120° C ... [Pg.279]

Several cleaning formulations for specific uses contain unreacted polyamines. Examples include mixtures of ammonium alkylbenzenesulfonate, solvents, and PIP which give good cleaning and shine performance on mirrors and other hard surfaces without rinsing (305), and a hard-surface cleaner composed of a water-soluble vinyl acetate—vinyl alcohol copolymer, EDA, cyclohexanone [108-94-1] dimethyl sulfoxide [67-68-5] a surfactant, and water (306). TEPA, to which an average of 17 moles of ethylene oxide are added, improves the clay sod removal and sod antiredeposition properties of certain hquid laundry detergents (307). [Pg.48]

Although being qualitatively in agreement with experimental results, disagreements between experiment and theory remain. Besides the composition, /a, and the total degree of polymerization, N, all theoretical works refer to the segmental interaction parameter x This parameter can be estimated from a relationship to the solubility parameters. The ODT as a thermodynamic measure of the incompatibility was used to compare a set of symmetrically composed diblock copolymers from different hydrocarbons, polydimethyl-siloxane and poly(ethylene oxide) (PEO) [33]. While the behaviour of hydrocarbon diblock copolymers was successfully described by a consistent set of solubility parameters, this procedure failed for systems containing PEO. The... [Pg.146]

Unsaturations of hydroxy-containing compounds are reduced on reaction with nitrile oxides such as tetramethyl terephthalonitrile N,N -dioxide (506) or 1,3,5-triethylbenzene-2,6-dicarbonitrile oxide (507). The reaction of a nitrile oxide with terminal unsaturation, associated with the preparation of a poly-ol from propylene oxide, reduces the mono-ol content of the poly-ol composition. Thus, stirring a solution of an ethylene oxide-propylene oxide copolymer with an OH content of 2.39% and vinyl unsaturation of 3.58% in THF with l,3,5-triethylbenzene-2,6-dicarbonitrile oxide for 1 min results in an effective removal of the terminal unsaturation. [Pg.103]

We have shown that polymeric micelles constmcted of block copolymers of poly(ethylene oxide) (PEG) and poly(L-asparate) containing the anticancer dmg (adriamycin, ADR) selectively accumulate at solid tumor sites by a passive targeting mechanism. This is likely due to the hydrophilicity of the outer PEG chains and micellar size (<100 nm) that allow selective tissue interactions [17,18]. Polymeric micelle size ranges are tailored during polymer synthesis steps. Carefully selection of block polymer chemistry and block lengths can produce micelles that inhibit nonselective scavenging by the reticuloendothelial system (RES) and can be utilized as targetable dmg... [Pg.28]

Telechelic polymers, containing one or more end groups with the capacity to react with other molecules, are useful for synthesizing block and other copolymers [Fontanille, 1989 Hsieh and Quirk, 1996 Nuyken and Pask, 1989 Pantazis et al., 2003 Patil et al., 1998 Quirk et al., 1989, 1996 Rempp et al., 1988]. Living anionic polymers can be terminated with a variety of electrophilic reagents to yield telechelic polymers. For example, reaction with carbon dioxide, ethylene oxide, and allyl bromide yield polymers terminated with carboxyl, hydroxyl, and allyl groups, respectively. Functionalization with hydroxyl or carboxyl groups can also be achieved by reaction with a lactone or anhydride, respectively. Polymers with amine end... [Pg.439]

Asatekin A, Kang S, Elimelech M et al (2007) Anti-fouling ultrafiltration membranes containing polyacrylonitrile-graft-poly(ethylene oxide) comb copolymer additives. J Membr Sci 298 136-146... [Pg.124]

New polymeric solid supports have been devised, which include macroporous styrene-divinylbenzene containing large fixed pores, porous glass beads, insoluble carbohydrate polymers, poly(ethylene oxide), cross-linked derivatives of polyacrylamide resins, and graft copolymers of polystyrene and poly(ethylene oxide). The last two have been the most effective and widely used and have competed well with the original copoly(styrene-divi-nylbenzene) beads. [Pg.22]

Polypropylene oxide is less hydrophilic than PEO. Block copolymers of propylene oxide and ethylene oxide (Pluronics) contain lyophilic and hydro phiiic domains and are used as urface active agents. [Pg.166]


See other pages where Ethylene oxide containing copolymers is mentioned: [Pg.308]    [Pg.500]    [Pg.146]    [Pg.312]    [Pg.251]    [Pg.350]    [Pg.27]    [Pg.8]    [Pg.753]    [Pg.27]    [Pg.26]    [Pg.49]    [Pg.452]    [Pg.153]    [Pg.120]    [Pg.127]    [Pg.25]    [Pg.105]    [Pg.313]    [Pg.221]    [Pg.74]    [Pg.107]    [Pg.178]    [Pg.157]    [Pg.228]    [Pg.269]    [Pg.3]    [Pg.318]    [Pg.605]    [Pg.762]    [Pg.37]    [Pg.8]   
See also in sourсe #XX -- [ Pg.48 ]




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Containers ethylene

Containers ethylene oxide

Copolymer containing

Copolymers ethylene

Copolymers oxide)

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