Hydroxy ethyl starch

Fig. 1.56.1. Course of main drying observed by a cryomicroscope, in which the freeze drying is carried out. The hydroxy ethyl starch solution is optimally frozen (see Fig. 1.37). The dark lines show the form of the sublimated ice crystals (Fig. 9 from [1.106]).

Luo Q, Wang P, Miao Y, He H, Tang X. A novel 5-fluorouracil prodrug using hydroxy-ethyl starch as a macromolecular carrier for sustained release. Carbohydr Polym... 

Penford Gum [Penford]. TM for hydroxy-ethyl ether derivatized com starches. 

Hydroxy ethylated, acid-treated, oxidized starch Bondagel E-1000 + E-125 or SynChropak lOOOA-(-2 X 500A DMSO and H O mixture with or without buffer MW, operatii study... 

In drilling fluid applications, several types of viscosity modifiers can be used to enhance foam stablity. These include partially hydrolyzed polyacrylamide (PHPA) clays, such as bentonite xanthan gum guar gums starches cellulosic polymers, such as hydroxy ethyl cellulose (HEG) and sodium carboxy methyl cellulose (SCMC). In Table 8, base fluid viscosities and drainage times for one-half and four-fifths of the base fluids are recorded in a foam system consisting of an anionic foamer, sodium lauryl sulfate (SLS) and a nonionic foamer, TXlOO - ethoxylated octyl phenol. It can be seen that in these systems base fluid viscosity alone... 

Numerous ethers of cellulose, starch, and bacterial dextran are of established or potential industrial importance. (See also Chapter XII.) Treatment of the polysaccharides with alkali and methyl chloride, ethyl chloride, benzyl chloride, ethylene oxide (or ethylene chlorohydrin), sodium chloro-acetate, and allyl bromide gives, respectively, the methyl, ethyl, benzyl, hydroxy ethyl, carboxy methyl, and allyl ethers. The cellulose derivatives... 

Condensation reactions between hydroxyethyl cellulose or carboxy methyl hydroxy-ethyl cellulose provides potentially useful textile sizing resins.Starch materials have been treated with MA to obtain starch with maleate half-ester residues, with a substitution degree of 0.01-3.00. Styrene monomer is grafted onto the maleate/fumarate residues, with high efficiency, using standard free-radical initiators. 

Another advantage is that natural polymers can be modified using suitable reagents to obtain semisynthetic polymers. Modified starch/dextran, cyclodextrins, cellulose, alginate, scleroglucan and chitosan derivatives are the most important semisynthetic polymers for the drug industry [17-19]. In this respect, starting from the natural cellulose, at least 10 semisynthetic derivatives are widely used for the optimization of pharmaceutical formulations cellulose acetate (CA), cellulose acetate butyrate (CAB), cellulose acetate phthalate (CAP), methylcellulose (MC), ethylcellulose (EC), hydroxy-ethyl cellulose (HEC), hydroxypropyl cellulose (HPC), hydroxypropyl methylcellulose (HPMC), carboxymethylcellulose (CMC), nitrocellulose [16,20,21]. 

Starch is added at the calender stack for curl control, surface strength, laying of surface fuzz, clay coating holdout, printing characteristics, and grease or oil resistance. Solids vary from 2 to 24%, depending on the starch type used and on the paper requirements. Low viscosity starches, hydroxy ethylated converted starches, and oxidized starches are used in this application. 

Thickeners added to an adhesive will raise viscosity and permit dilution with water. This reduces the total solids of the adhesive and thus lowers its (wet) cost. Thickeners release water slowly, and when combined with lower solids, they also slow the setting (prolong open time) of the adhesive. Thickeners such as polyvinyl alcohol, starch, and hydroxy ethyl cellulose will improve adhesion to porous substrates by reducing penetration of an emulsion into the substrate and decreasing the likelihood of a starved joint. ... 

HYDROXY-2-ETHYL-4-PYRONE see ENL 600 HYDROXYETHYL STARCH see HLB400... 

Quinones Barrier [6] has separated some benzoquinones on silica-starch layers, using hexane-ethyl acetate (85 + 15). Pettersson [169] later made a detailed comparison of the chromatographic behaviour of benzoquinones, of which 31 contained hydroxyl group(s) and 21 were without. Neutral solvents, especially mixtures of benzene-chloroform and xylene, were suitable for the last named. The basic solvent VIII (Table 166) was better for the more polar hydroxy-quinones they migrate as enolates in this system. The hi /-values on silica gel layers of some recently discovered [170] fungus colouring materials are given below they were obtained with solvent VIII (values without brackets) and chloroform (values in brackets) ... 

---