Polyethylene oxide , PEG

A large number of polymeric compounds have been investigated, but most modem propellants utilize prepolymers that ate hydroxy-functional polybutadienes (HTPB), carboxy-functional polybutadienes (CTPB), or a family of polyethylene oxides (PEGs) to form urethanes. Typical cure reactions... 

Yang and coworkers did the most efforts on the development of network polyester based on citric acid. " They investigated the reaction of citric acid with a series of aliphatic diols (from 3-16 carbon chains) and polyether diols such as polyethylene oxide (PEG), in which 1,8-octanediol (POC) and 1,10 decanediol (PDC) have been studied the most. 

Ethoxylated methylcarboxylates Propoxyethoxy glyceryl sulfonate Alkylpropoxyethoxy sulfate as surfactant, xanthan, and a copolymer of acrylamide and sodium 2-acrylamido-2-methylpropane sulfonate Carboxymethylated ethoxylated surfactants (CME) Polyethylene oxide (PEG) as a sacrificial adsorbate Polyethylene glycols, propoxylated/ethoxylated alkyl sulfates Mixtures of sulfonates and nonionic alcohols Combination of lignosulfonates and fatty amines Alkyl xylene sulfonates, polyethoxylated alkyl phenols, octaethylene glycol mono n-decyl ether, and tetradecyl trimethyl ammonium chloride Anionic sodium dodecyl sulfate (SDS), cationic tetradecyl trimethyl ammonium chloride (TTAC), nonionic pentadecylethoxylated nonylphenol (NP-15), and nonionic octaethylene glycol N-dodecyl ether Dimethylalkylamine oxides as cosurfactants and viscosifiers (N-Dodecyl)trimethylammonium bromide Petrochemical sulfonate and propane sulfonate of an ethoxylated alcohol or phenol Petrochemical sulfonate and a-olefin sulfonate... 

Abbreviations HPMC, hydroxypropyl methyl cellulos PEO, polyethylene oxide PEG, polyethylene glycol. 

Harada et al. explored the compatibility of CD with various polymeric backbones including polyethylene oxide) (PEG), polypropylene oxide) (PPG), polyisobutylene (PIB), and polyethylene (PE) [77-87]. The corresponding polyrotaxanes (36 to 47) were prepared by Method 2, simply by mixing a solution of CD and the polymer. The cavity size of CD was found to be the main factor in the threading process. While one a-CD (20) was threaded per two repeat units in PEG (m/n=0.50) and every three repeat units for PE (m/n=0.333), it was too small for PIB and PPG. On the other hand, two PPG units complexed per /(-CD (21). Because the upper limit of the min value is controlled by the depth of the CD cavity, the m/n value remained constant for the same type of backbone, irrespective of the end group. However, the nature and concentration, i.e., polymer... 

Tonelli and coworkers [18] prepared two inclusion complexes of the a- and y-cyclodextrin with poly(c-caprolactone) (PCL) and polyethylene oxide (PEG) PCL-PEO-PCL-a-cyclodextrin and PCL-PEO-PCL-y-cyclodextrin. The channel structures of both the triblock inclusion complexes obtained were characterized by several methods (TGA, DSC, X-ray diffraction, FTIR and Solid State NMR spectroscopy). 

Poly(D(-)-3-hydroxybutyrate miscibility has been reported with polyvinylacetate (PVAC) [Greco and Martuscelli, 1989], poly(p-vinyl phenol) [Xing et al., 1997], and polyethylene-oxide (PEG) [Avella and Martuscelli, 1988]. Phase separation of poly(3-hydroxy butyrate-co-... 

Separation of a technical polyethylene oxide (PEG) by liquid chromatography at the critical point of adsorption and analysis of fraction by MALDl-MS. Peak assignment indicates degree of polymerization (n). Column Nucleosil 100 RP-18 (126 x 4 mm I.D.) eluent acetonitrile-water (70 30 v/v). (Reprinted with permission from Ref. 176)... 

Belenkii et al. reported in 1975 (8) the SEC of PVP with unspecified molecular weight using Pharmacia Sephadex G-75 and G-lOO columns and a 0.3% sodium chloride solution as the mobile phase. Deviations from universal calibration behavior were noticed from PVP, dextran, polyethylene oxide (PEG), and polyvinyl alcohol. With the development of the important semirigid polymer gel, Toyo Soda TSK-PW columns for water-soluble polymers, Hashimoto et al. reported in 1978 (9) the SEC of PVP K-30 and K-90 using TSK-PW 3000 and two 5000 columns an 0.08 M Tris-HCl buffer (pH =... 

Poloxamers consist of two polyethylene oxide (PEG) blocks attached on both sides of a polypropylene oxide (PPO) block. The polymers are water-soluble, but increasing the temperature or concentration can lead to gel formation. The gelling properties are a function of the polypropylene content and the block lengths. Figure 11.12 shows the viscosity as a function of temperature for poloxamer 407. For a given concentration of poloxamer, the viscosity increases by several orders of magnitude at a transition temperature. The transition temperature decreases as polymer concentration increases. 

Polyethylene glycol (PEG) is another well-known molecule used to reduce protein adsorption and/or platelet adhesion. Surface enrichment of a triblock oligomeric PEG containing additive from a polyurethane matrix was reported [54,55]. The authors used PEG as the active groups to suppress protein and platelet adhesion. The authors first synthesized a methylene diphenyl diisocyanate (MDI)-poly (tetramethylene oxide) (PTMO) 1000 prepolymer with a MW of approximately 4750 (PU4750), and then this prepolymer was terminally functionalized with mono amino-polyethylene oxide (PEG) with different MW (PEO550, 2000, or 5000, Table 2.3). This triblock copolymer was mixed with a polyurethane (MDI/ PTMO 1000/ethylene diamine (ED)) at different ratios in dimethylformamide (DMF) and cast into polymer films. The surface compositions of these films were evaluated by XPS. 

In total, four different bounding liquids that have a widely different degree of compatibility with PDMS (as expressed by the interfacial tension between the liquid and PDMS, Kpdms-iiquid) were used for experiments PW, EG, aqueous solutions of surfactant L77 (polyalkyleneoxide-modified heptamethyltrisiloxane) and a short Mw = 3 k) water-soluble diblock (80/20) copolymer with a small polyethylene oxide (PEG) block, that is, PDMS-PEO (PP). The concentrations of aqueous solutions were about five times the critical micellar concentration in absolute terms the concentration was 0.00025 v/v for L77 and 0.01 v/v for PP, respectively. 

The vapor pressure data obtained by means of HS-GC measurements for the solutions of PS (below the glass transition temperature of the polymer) in the favorable solvent TL resemble closely the results for the solutions of polyethylene oxide (PEG) in chloroform (below the melting temperature of the polymer), as shown later. The common denominator of these processes lies in the loss of mobility of the macromolecules. The results presented in Fig. 7 can be interpreted in the following manner The composition range of constant vapor pressure ( ... 

PCL shows high-molecular-chain flexibility and outstanding processability. It can be spun into fibers or blown films under 200°C without thermal degradation. The drawback of PCL is its low melting point ( 60°C) and low glass transition temperature (approx. -60°C), which prohibited its applications at elevated temperatures [102]. Therefore, PCL is often blended with other polymers, such as PP, polycarbonate (PC), polyethylene oxide (PEG), and starch, to produce... 

Apart from polyethylene glycols, Sadeghi et al. [185, 235, 236] used polyvinyl pyrrolidone (PVP) with trisodium and tripotassium citrates in establishing the aqueous two-phase systems. The binodal curves and tie-lines in these systems were determined in the 25-55 °C temperature range. Polyethylene oxide (PEG) and polypropylene oxide (PPG) were also utilized to form the aqueous two-phase systems with trisodium citrate. For example, daRocha Patricio etal. [237] investigated PEG 1500 systems at 10, 25 and 40 °C. Two-phase systems consisting water, triblock copolymers formed from ethylene oxide and propylene oxide units and trisodium citrate were smdied at 15, 35 and 45 °C by drtuoso et al. [238]. 

Benzothiozolon-3-yl Acetic Acid-telechelic Polyethylene Oxides (PEG Esters)... 

Polymeric proton electrolytes based on the composite of silicotungstic (12-HSiW) and polyethylene oxide (PEG) form a new compound 12-HSiW-PEG, as the ether oxygens of the PEG get associated with HsG cations originated from 12-HSiW and show a substantial increase in proton conductivity [130]. The decrease in the crystallinity of the films at high relative humidities is conducive to the transfer of the hydroxoniums in the composite polymer films, and hence to the... 

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