As viscosity-increasing agent

In 1988, Terry and coworkers attempted to homopolymerize ethylene, 1-octene, and 1-decene in supercritical C02 [87], The purpose of their work was to increase the viscosity of supercritical C02 for enhanced oil recovery applications. They utilized the free radical initiators benzoyl peroxide and fert-butyl-peroctoate and conducted polymerization for 24-48 h at 100-130 bar and 71 °C. In these experiments, the resulting polymers were not well studied, but solubility studies on the products confirmed that they were relatively insoluble in the continuous phase and thus were not effective as viscosity enhancing agents. In addition, a-olefins are known not to yield high polymer using free radical methods due to extensive chain transfer to monomer. 

Carboxymethylcellulose calcium is also used in other applications similarly to carboxymethylcellulose sodium for example, as a suspending or viscosity-increasing agent in oral and topical pharmaceutical formulations. Carboxymethyl-... 

In oral solutions, glycerin is used as a solvent, sweetening agent, antimicrobial preservative, and viscosity-increasing agent. It is also used as a plasticizer and in film coat-ings. Glycerin is additionally used in topical formulations such as creams and emulsions. " ... 

Glyceryl behenate is used in cosmetics, foods, and oral pharmaceutical formulations. In cosmetics, it is mainly used as a viscosity-increasing agent in emulsions see Table I. 

Povidone is additionally used as a suspending, stabilizing, or viscosity-increasing agent in a number of topical and oral suspensions and solutions. The solubility of a number of poorly soluble active drugs may be increased by mixing with povidone. See Table II. 

Another concern is the effect of multiple particle sizes. In general, the presence of fine particles will affect the requirements of suspension of larger particles. The fine particles act largely as a potential viscosity-increasing agent and give a similar result to what would happen if the viscosity of the continuous phase were increased. 

Hyaluronic Acid also acts in the body as a viscosity-increasing agent or lubricating agent in the vitreous humor of the eye and synovial fluid of joints. 

The tendency for alternation of monomers in a styrene-maleic anhydride and styrene-acrylonitrile copolymers at moderate temperatures has been attributed to the formation of a charge transfer complex (CTC) between a donor (D) and an acceptor (A). This CTC is readily detectable by UV or nmR spectroscopy. More important, the equilibrium constant decreases as the temperature is increased and this effect can be followed by instrumental analysis. Thus it is possible to extrapolate to a higher temperature at which the CTC does not exist (16). Thus, by proper temperature control, it is possible to produce SMA alternating copolymers, block copolymers of vinyl monomers with both alternating and random SMA (17) and completely random copolymers of SMA (18). Half esters of SMA have been used as viscosity control agents in petroleum crudes (19). 

Purified c. is approved for ->food applications and used in ice cream formulations as crystallization inhibitor and in pet food. The pharmaceutical industry makes use of the property of c. to be insoluble in acidic media (stomach) and soluble in alkaline environments (intestine). Other uses are for dental impressions and in toothpaste. Cross-linked c. is used as a most powerful water absorbent in hygienic applications such as diapers and tampons. The sodium and calcium salts are used as suspending and viscosity-increasing agents in pharmaceutical applications. They act also as tablet binders as well as tablet disintegrating agents. CMMC is an effective film former in the manufacture of -> tobacco sheets. 

The viscosity of solutions is quite temperature dependent increasing the temperature leads to a reduction in viscosity, which approaches zero at approximately 60°C (322). The viscosity is relatively stable from pH 3—10 and is compatible with a number of inorganic salts other than sodium. The production of succinoglycan and its potential use in foods and industrial processes as a thickening agent has been described (322). 

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