Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

OXYPROPYLENE COPOLYMER

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]

Several recent reviews have included a discussion of the ordered micellar phase phase behaviour of poly(oxyethylene)/poly(oxypropylene) copolymers (Alexandridis and Hatton 1995 Chu and Zhou 1996) and poly(oxyethylene)/ poly(oxybutylene) copolymers (Booth et al, 1997),... [Pg.222]

Attwood, D. Collett, J.H. Tait, J.C. The micellar properties of the poly(oxyethylene)-poly(oxypropylene) copolymer Pluronic FI27 in water and electrolyte solution. International Journal of Pharmaceutics 1985, 26, 25-33. [Pg.1069]

Stead, J. B., Hindley, A. H. 1969. Analysis of oxyethylene/oxypropylene copolymers by chemical fission and gas chromatography. J. Ghromatogr. 42 470-475. [Pg.270]

Details are given of the equilibrium thermorheological properties of oxyethylene-oxypropylene copolymers. The effect of molecular weight, solute and solvent composition on the structural properties was investigated. The efficacy of these copolymers in drug delivery systems is discussed. 32 refs. [Pg.70]

Po]y(oxyethylene)/Poly(oxypropylene) copolymer star structure ... [Pg.1665]

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]

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... [Pg.2606]

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]

Pluronic L62 is a poly(oxyethylene)—poly(oxypropylene)—poly(oxyethylene) copolymer marketed by BASF AG. [Pg.465]

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. [Pg.55]

Porous membranes have been prepared by leaching an additive from films and tubes of PCL (64,72). The procedure involves extrusion or casting blends of PCL and Pluronic F68, the latter being an FDA-approved oxyethylene-co-oxypropylene triblock copolymer. Treatment of the phase-separated blend with aqueous acetone or aqueous alcohols causes both swelling of the polymer and extraction of the Pluronic F68. The induced pore size and void volume may be controlled by the time, temperature, and solvent composition. [Pg.88]

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. [Pg.623]

Polyglycols, especially poly(propylene-l,2- or -1,3-glycol). Poly(oxyethylene) and poly(oxypropylene) block copolymers have relatively poor foam control [536]. [Pg.284]

An early review of micellization in block copolymers was presented by Tuzar and Kratochvfl (1976), and these authors have recently provided an excellent review of the literature up to 1992 (Tuzar and Kratochvfl 1993). Micellar properties of block copolymers were also reviewed by Price (1982). A discussion of micellization was included in the general reviews on block copolymers by Riess et al. (1985) and Brown et al. (1989). Excellent reviews focussed on the solution properties of a particular class of copolymer, i.e. copolymers of polyoxyethylene) with poly(oxypropylene) have been presented by Alexandridis and Hatton (1995) and by Chu (1995) and Chu and Zhou (1996). Micellization and micellar association in related poly(oxyethylene)/poly(oxybutylene) copolymers have been summarized by Booth et al (1997). [Pg.132]

Ordered phases in poly(oxyethylene)/poly(oxypropylene) block copolymer solutions... [Pg.227]

P. Chekhonin, I. R. Nazarova, and V. A. Kabanov. 1992. A new class of drug carriers micelles of poly(oxyethylene)-poly(oxypropylene) block copolymers as microcontainers for drug targeting from blood in brain.J. Control. Rel22 141-158. [Pg.367]

Zhou, Z. and B. Chu. 1994. Phase behavior and association properties of poly(oxypropylene)-poly(oxyethylene)-poly(oxypropylene) triblock copolymer in aqueous soluftdacromolecule 7 2025-2033. [Pg.374]

Wanka, G., H. Hoffmann, and W. Ulbricht. 1994. Phase diagrams and aggregation behaviour of poly(oxythylene)-poly(oxypropylene)-poly(oxyethylene) triblock copolymers in aqueous solutions. Macromolecules 27 4145. [Pg.520]

Foly(oxyethylene)-Foly(oxypropylene) Block Copolymer in Aqueous Solution After Exposure to High-Energy Irradiation... [Pg.128]

Materials. Pluronic FI27 was a gift from Pechiney Ugine Kuhlmann and was used as received. Pluronic F127 is an ABA poly(oxyethylene)-poly(oxypropylene)-poly(oxyethylene) block copolymer containing approximately 70% oxyethylene with a nominal molecular weight of 1.15 x 10. ... [Pg.129]

See other pages where OXYPROPYLENE COPOLYMER is mentioned: [Pg.799]    [Pg.761]    [Pg.741]    [Pg.1044]    [Pg.498]    [Pg.828]    [Pg.669]    [Pg.972]    [Pg.2520]    [Pg.3065]    [Pg.799]    [Pg.761]    [Pg.741]    [Pg.1044]    [Pg.498]    [Pg.828]    [Pg.669]    [Pg.972]    [Pg.2520]    [Pg.3065]    [Pg.334]    [Pg.24]    [Pg.285]    [Pg.113]    [Pg.117]    [Pg.121]    [Pg.124]    [Pg.282]    [Pg.140]    [Pg.141]    [Pg.223]    [Pg.227]    [Pg.295]    [Pg.128]    [Pg.128]    [Pg.334]    [Pg.335]   
See also in sourсe #XX -- [ Pg.93 ]



SEARCH



OXYPROPYLENE

© 2024 chempedia.info