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Hydroxyethylcellulose HEC

Peak Notation Assignment of Main Peaks Molecular Weight Retention Index Relative Intensity [Pg.316]

Carboxymethylcellulose, polyethylene glycol Combination of a cellulose ether with clay Amide-modified carboxyl-containing polysaccharide Sodium aluminate and magnesium oxide Thermally stable hydroxyethylcellulose 30% ammonium or sodium thiosulfate and 20% hydroxyethylcellulose (HEC) Acrylic acid copolymer and oxyalkylene with hydrophobic group Copolymers acrylamide-acrylate and vinyl sulfonate-vinylamide Cationic polygalactomannans and anionic xanthan gum Copolymer from vinyl urethanes and acrylic acid or alkyl acrylates 2-Nitroalkyl ether-modified starch Polymer of glucuronic acid... [Pg.12]

Hydroxyethylcellulose HEC Water and GI fluids Properties similar to MC, but gives clear solutions... [Pg.325]

Shellflo-XA, a proprietary grade of xanthan and cellobond X-100 a hydroxyethylcellulose (HEC) were used for comparative purposes. [Pg.163]

Within this group, the linear polymers have been most intensively studied and researched. The main area of interest lies in water-soluble polymers. However, there have also been many studies into organic solutions, although there exist problems with odor and toxicity in the case of analytical studies. Among the water-soluble additives, tests were made especially on polyethyleneoxide (PEO), polyacrylamide and the coacrylates (PAAm, PAAm/AAcNa), polyacrylic add (PAA), guar gum (GG), carboxymethylcellulose (CMC) and sodium salts, as well as hydroxyethylcellulose (HEC). From these tests, PEO proved to be the most effective flow improver, followed closely by PAAm, which is somewhat more stable than PEO in turbulent flow. [Pg.124]

The commercialization of new watei-soluble polymers is most often a slow process. For example, hydroxyethylcellulose (HEC) was envisaged in 1937 by... [Pg.319]

Hydroxypropyl cellulose (HPC) Hydroxyethylcellulose (HEC) Methylcellulose (MC) Polvinyl alcohol (PVA) Polyacrylic acid (PAA) Poly (meth) acrylic acid ester (PMAA) Polyvinyl pyrrolidone (PVP) Polyethylene glycols (PEG) White wax... [Pg.154]

A popular approach to improve ocular drag bioavailability is to incorporate soluble polymers into an aqueous solution to extend the drug residence time in the cul-de-sac. It is reasoned that the solution viscosity would be increased and hence solution drainage would be reduced. The more commonly used viscolyzing agents include PVA and derivatives of cellulose. Cellulosic polymers, such as methylcellulose, hydroxyethylcellulose (HEC), hydroxypropyl-methylcellulose (HPMC) and hydroxypropylcellulose (HPC), are widely used as viscolyzers showing Newtonian properties. They have common properties ... [Pg.308]

Ruhr s group studied the separation of double- and single-stranded DNA restriction fragments in capillary electrophoresis with polymer solutions under alkaline conditions in epoxy-coated capillaries and found that at pH 11 the theoretical plate numbers exceeded several millions [96], At pH 12, single-stranded DNA molecules were still well separated in entangled hydroxyethylcellulose (HEC) solutions, but the resolution decreased significantly in dilute polymer solutions. [Pg.90]

Hydroxyethylcellulose (HEC) and hydroxypropylcellulose (HPC) are prepared by reacting cotton linter or woodpulp with aqueous sodium hydroxide, and the resulting alkali cellulose is reacted with ethylene oxide and propylene oxide, respectively. [Pg.297]

Figure 1.4 Network structure formed by an aqueous surfactant solution mixed with an associative thickening polymer hydroxyethylcellulose (HEC) with cetyl (16-carbon alkyl) side branches. (Reprinted from Clarke 1993, by courtesy of Marcel Dekker, Inc.)... Figure 1.4 Network structure formed by an aqueous surfactant solution mixed with an associative thickening polymer hydroxyethylcellulose (HEC) with cetyl (16-carbon alkyl) side branches. (Reprinted from Clarke 1993, by courtesy of Marcel Dekker, Inc.)...
Other non-ionic cellulose ethers which have been stndied in the formulation of hydrophilic matrices include high viscosity grades of hydroxypropylcellulose (HPC) and hydroxyethylcellulose (HEC) [24]. The ionic cellulose ether, sodium carboxymethylcellulose (Na CMC), with low or medium viscosity grades has... [Pg.222]

Width s, in particular, was varied s/D = 0.02-0.09. Hydroxyethylcellulose HEC was Used as the liquid, whose rheological behavior obeys the power law and which exhibits practically no viscoelasticity. In the range of Re ff = 10" -10 nO values increased slightly with Rees-... [Pg.115]

Cellulose ethers can be prepared by various methods, as by using the common Williamson ether synthesis, with alkyl halides in the presence of a strong base (Fig. 32). This procedure is most often used to introduce carboxyl functions [O-carboxymethylcellulose (CMC)] or hydroxyl groups [3-hydroxypropylcellulose (HPC) and 2-hydroxyethylcellulose (HEC)]. [Pg.72]

See other pages where Hydroxyethylcellulose HEC is mentioned: [Pg.497]    [Pg.121]    [Pg.77]    [Pg.459]    [Pg.489]    [Pg.121]    [Pg.497]    [Pg.235]    [Pg.315]    [Pg.83]    [Pg.31]    [Pg.297]    [Pg.893]    [Pg.102]    [Pg.1521]    [Pg.337]    [Pg.340]    [Pg.546]    [Pg.526]    [Pg.204]    [Pg.96]    [Pg.533]    [Pg.551]    [Pg.179]    [Pg.65]    [Pg.233]    [Pg.479]    [Pg.1279]    [Pg.1449]   


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HEC

Hydroxyethylcellulose

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