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Polyethylene oxidized

Nonionic Polyethylene oxide Polyethylene glycol Polysaccharides Pullulans Dextrans Cellulosics Polyvinyl alcohol Polyacrylamide 0.1 M NaNOj... [Pg.344]

Nonionic, hydrophilic Polyethylene oxide, polyethylene glycol Polyviny alcohol, hydroxyethyl cellulose, polyacrylamide Pure water 0.1-0.2 M salt/buffer, pH 7... [Pg.364]

In some cases it is possible to differentiate between the various alkyl substituents. Primary, secondary and tertiary nitrates and nitrites all show clearly different infrared absorptions. The spectra of acid fluorides can be used to differentiate chain-end groups from pendant acid groups. Furthermore, the loss of all -OH species upon sulfur tetrafluoride exposure allows the reliable estimation of ketones, esters and lactones without the complication of hydrogen-bonding induced shifts in the spectra. Preliminary results from the use of these reactions to characterize y-ray oxidized polyethylene and polypropylene are used to illustrate the scope of the methods. [Pg.376]

Polyacetal Polyacrylamide Polyacrylonitrile Polycarbonate Polyethylene Polyethylene oxide Polyethylene terephthalate Poly isobutyl methacrylate Poly methacrylic acid Polymethyl methacrylate Polymonochlorotrifluoro ethylene Polypropylene Polystyrene... [Pg.141]

PA Ivanchenko. Mechanism of C—C Bond Scission in Oxidized Polyethylene. PhD Thesis Dissertation, Institute Chemical Physics, Chernogolovka, 1979, [in Russian]. [Pg.486]

Preservative 914 Oxidized polyethylene wax Acc 26th Series Not evaluated... [Pg.273]

In an extension of this work, the reuse of the polymeric catalyst was addressed and several new PE-poly(alkene) glycol copolymers were prepared [68]. Commercially available oxidized polyethylene (CO2H terminated, both high and low molecular weight) was converted to the acid chloride and reacted with Jeffamine D or Jeffamine EDR, and subsequently converted to the tributylammonium bromide salt with butyl bromide. These new quaternary salts were shown to catalyze the nucleophihc substitution of 1,6-dibromohexane with sodium cyanide or sodium iodide. While none of the polymeric quaternary salts catalyzed the reaction as well as tetrabutylammonium bromide, the temperature-dependent solubility of the polymers allowed removal of the polymer by simple filtration. [Pg.252]

Fig. 7 Fluorescence spectra of a 5-PAA/PE graft (a) after treatment with 10 (filled squares), (b) after washing with THF in a Soxhlet apparatus for 24 h (open squares)-, (c) after treatment with NaOH (open circles). For comparison purposes, a fluorescence spectrum for an oxidized polyethylene Aim without any hyperbranched graft (but with - CO2H groups) that was also treated with 10 is also shown (filled circles)... Fig. 7 Fluorescence spectra of a 5-PAA/PE graft (a) after treatment with 10 (filled squares), (b) after washing with THF in a Soxhlet apparatus for 24 h (open squares)-, (c) after treatment with NaOH (open circles). For comparison purposes, a fluorescence spectrum for an oxidized polyethylene Aim without any hyperbranched graft (but with - CO2H groups) that was also treated with 10 is also shown (filled circles)...
Based on the results obtained to date, which have been summarized above for several different semicrystalline polymers— linear and low density (branched) polyethylene, polytrimethylene oxide, polyethylene oxide and cis polyisoprene—it is concluded that the relatively fast segmental motions, as manifested in Tq, are independent of all aspects of the crystallinity and are the same as the completely amorphous polymer at the same temperature. Furthermore, it has previously been shown that for polyethylene, the motions in the non-crystalline regions are essentially the same as those in the melts of low molecular weight ii-alkanes. (17)... [Pg.197]

Fig. 22 Images and data representing development and application of DLS on a chip a one iteration in the design of a microfluidic DLS fabricated from aluminum with the surface anodized black to reduce surface reflections b image of a microfluidic chip that integrates polymer synthesis with DLS. The machined channels have been covered by a Kapton sheet fixed with adhesive c data for temperature depended micelle formation of polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer (Pluronic P85) at 2% by volume in water. (Derived from [106] with permission)... Fig. 22 Images and data representing development and application of DLS on a chip a one iteration in the design of a microfluidic DLS fabricated from aluminum with the surface anodized black to reduce surface reflections b image of a microfluidic chip that integrates polymer synthesis with DLS. The machined channels have been covered by a Kapton sheet fixed with adhesive c data for temperature depended micelle formation of polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer (Pluronic P85) at 2% by volume in water. (Derived from [106] with permission)...
Entry Catalyst Productivity Propylene Oxide/ Polyethylene Glycol Selectivity (%) Propylene Selectivity (%)... [Pg.286]

The nonionic triblock copolymer polyethylene oxide-polypropylene oxide polyethylene oxide (PEO-PPO-PEO) has been widely used in medicine and has shown low toxicity. Wanka et al. [91] studied aggregation behavior of PEO-PPO-PEO polymeric micelles. In this study, the hydrophobic core of this micellar system consisted of dehydrated poly(oxy-propylene) groups which were surrounded by an outer shell of hydrated poly(oxyethylene) groups. The feasibility of using PEO-PPO PEO micelles as a topical ocular carrier for gene delivery was addressed in an in vivo study on nude mice and albino rabbits [92], Each animal eye was treated with a topical application (10 pL for mouse and 50 pL for rabbit) of 0.08 mg/mL of plasmid and 0.3% (w/v) PEO-PPO-PEO polymeric micelles. After 2 days of three times per day topical delivery, the reporter expression was detected in the treated eyes... [Pg.506]

Formaldehyde, along with other short-chain aldehydes such as acetaldehyde, is a low molecular weight, volatile, reactive contaminant that can be present at low levels from a variety of sources (e.g., excipients such as polyethylene oxide, polyethylene glycol (64,65), or from carbohydrate degradation (66), solvent contamination (51), packaging materials (52), etc.). Formaldehyde is known to react with amines (Fig. 33) to form a reactive N-hydroxymethyl compound (a hemiaminal) that can further react with other nucleophiles. Reaction of formaldehyde with amino acids (67) can cause... [Pg.72]

Platform chemicals are compounds that serve as building blocks for numerous chemical intermediates and end products. An example is ethylene, which serves as the feedstock for derivatives such as acetaldehyde, ethylene dichloride, ethylene oxide, polyethylene, vinyl acetate, and ethyl acetate. Biobased chemicals such as succinic acid, 3-hydroxypropionic acid (3-HP), and butanol also have the potential to be converted into multiple derivatives, some of which are commodity chemicals and others that are higher-value chemicals. [Pg.878]

Ethylene oxide Polyethylene glycol 400 Potassium hydroxide... [Pg.2802]

Other important examples of ring-opening polymerizations are the synthesis of polyethylene oxide and the block copolymer of ethylene oxide and propylene oxide. Polyethylene oxide, also known as polyethylene glycol (PEG), is commonly produced by anionic polymerization and has a low molecular weight of less than 20,000. [Pg.483]

The use of SSL or lignosulphonates in other polymeric adhesive systems has also been examined [e.g., with polyacrylamide, proteins/aldehydes, polyethylene oxide, polyethylene imine, epoxides, melamine, styrene oxide, polyisocyanates (55)]. So far, these procedures, for different reasons, have not led to any major practical application (36). It would, however, be interesting to reexamine some of these processes using not crude spent sulphite liquors, but instead those purified by membrane filtration. [Pg.23]

MTX MCC mPEG MA NFX PEO PCS PECs PLA PBLA PLG PPO PEG PCL PBLG PBS PGA Methotrexate Crystalline cellulose Monomethoxypoly(ethylene glycol) Maleic acid Norfloxacin Polyethylene oxide) Photon correlation spectroscopy Poly(electrolyte complexes) Poly(L-lactic acid) Poly( 3-benzyl-L-aspartate) Poly (lactide- co -glycolide) Polypropylene oxide) Polyethylene glycol) Poly(e-caprolactone) Poly(y-benzyl-L-glutamate) Phosphate buffered saline Poly(glycolic acid)... [Pg.48]

Polyethylene Oxide Polyethylene oxide is a nonionic homopolymer of ethylene oxide synthesized by polymerization of ethylene oxide. It is available as a free-... [Pg.299]

It seems that oxidized polyethylene w/7/ biodegrade the first oxidation stage is the limiting step. Hence, time is the limiting factor. This can be addressed. [Pg.40]

Poly(ethylene glycol) is used in a number of copolymers, such as poly(propylene oxide-co-ethylene oxide), polyethylene-ft/oc/c-poly(ethylene glycol), poly [2,2-propanebis(4-phenyl)carbonate-b/oc/c-poly(ethyIene oxide], as well as in various polymer blends. Several pyrolysis studies were done on these copolymers [9-11]. [Pg.493]

Fig. 2 GC-MS chromatograms showing the products extracted from photo-oxidized polyethylene by traditional HS extraction (above) and by HS-SPME with polar car-bowax/divinylbenzene fiber (below). A few short-chain carboxylic acids were detected in the chromatogram after HS extraction, while carboxylic acids, ketones and furanones were detected after HS-SPME... Fig. 2 GC-MS chromatograms showing the products extracted from photo-oxidized polyethylene by traditional HS extraction (above) and by HS-SPME with polar car-bowax/divinylbenzene fiber (below). A few short-chain carboxylic acids were detected in the chromatogram after HS extraction, while carboxylic acids, ketones and furanones were detected after HS-SPME...
Keywords Catalysis intercalation polymerization kinetics layered clay nanocomposite oxidation polyethylene thermal degradation... [Pg.2]

Alexandridis P, Hatton TA. Polyethylene oxide)-poly(propylene oxide)- polyethylene oxide) block copolymer surfactants in aqueous solutions and at interfaces thermodynamics, structure, dynamics, and modeling (review). Colloid Surf A Physicochem Eng Aspects 1995 96 1-46. [Pg.290]


See other pages where Polyethylene oxidized is mentioned: [Pg.210]    [Pg.482]    [Pg.418]    [Pg.418]    [Pg.603]    [Pg.54]    [Pg.93]    [Pg.262]    [Pg.403]    [Pg.327]    [Pg.246]    [Pg.14]    [Pg.58]    [Pg.33]    [Pg.635]    [Pg.210]    [Pg.482]    [Pg.657]    [Pg.114]    [Pg.29]    [Pg.518]    [Pg.3588]    [Pg.422]    [Pg.28]    [Pg.546]   
See also in sourсe #XX -- [ Pg.605 ]

See also in sourсe #XX -- [ Pg.62 ]

See also in sourсe #XX -- [ Pg.456 , Pg.460 ]




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Polyethylene oxide

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