Natural gum

Like other polysaccharides, guar gum is used in cosmetics, as well as a stabilizing element in tablets and emulsions. [Pg.155]

Carob bean gum, or locust bean gum, is another type of mainly neutral galactomannan, and is found in the seeds of the leguminous Ceratonia siliqua Linn. Interestingly, carob [Pg.155]

Carob bean gum, alone or in combination with crosslinking compounds and other natmal polysaccharides, showed promising results in applications aimed at controlled drug releases [296,297], including TIMERx as a commercialized system [298]. [Pg.156]

Typical fields of application are shared with the gums already discussed matrix stabilizer, excipient, and ingredient for controlled drug release [299,303], but also in the field of dental adhesives [304]. [Pg.156]

Natural gas pipeline Natural gas wells Natural graphite Natural Graphite Natural gums... [Pg.662]

Emulsion Adhesives. The most widely used emulsion-based adhesive is that based upon poly(vinyl acetate)—poly(vinyl alcohol) copolymers formed by free-radical polymerization in an emulsion system. Poly(vinyl alcohol) is typically formed by hydrolysis of the poly(vinyl acetate). The properties of the emulsion are derived from the polymer employed in the polymerization as weU as from the system used to emulsify the polymer in water. The emulsion is stabilized by a combination of a surfactant plus a coUoid protection system. The protective coUoids are similar to those used paint (qv) to stabilize latex. For poly(vinyl acetate), the protective coUoids are isolated from natural gums and ceUulosic resins (carboxymethylceUulose or hydroxyethjdceUulose). The hydroHzed polymer may also be used. The physical properties of the poly(vinyl acetate) polymer can be modified by changing the co-monomer used in the polymerization. Any material which is free-radically active and participates in an emulsion polymerization can be employed. Plasticizers (qv), tackifiers, viscosity modifiers, solvents (added to coalesce the emulsion particles), fillers, humectants, and other materials are often added to the adhesive to meet specifications for the intended appHcation. Because the presence of foam in the bond line could decrease performance of the adhesion joint, agents that control the amount of air entrapped in an adhesive bond must be added. Biocides are also necessary many of the materials that are used to stabilize poly(vinyl acetate) emulsions are natural products. Poly(vinyl acetate) adhesives known as "white glue" or "carpenter s glue" are available under a number of different trade names. AppHcations are found mosdy in the area of adhesion to paper and wood (see Vinyl polymers). [Pg.235]

Natural gums are exuded in a variety of shapes characteristic of the species of origin. These shapes include the globular shape of gum arable and the flakes or thread-like ribbons of gum tragacanth (36). [Pg.434]

Larch gum is readily soluble in water. The viscosity of these solutions is lower than that of most other natural gums and solutions of over 40% soHds are easily prepared. These highly concentrated solutions are also unusual because of their Newtonian flow properties. Larch gum reduces the surface tension of water solutions and the interfacial tension existing in water and oil mixtures, and thus is an effective emulsifying agent. As a result of these properties, larch gum has been used in foods and can serve as a gum arabic substitute. [Pg.436]

Other thickeners used include derivatives of ceUulose such as methylceUulose, hydroxypropylmethylceUulose, and ceUulose gum natural gums such as tragacanth and xanthan (see Cellulose ethers Gums) the carboxyvinyl polymers and the poly(vinyl alcohol)s. The magnesium aluminum siHcates, glycol stearates, and fatty alcohols in shampoos also can affect viscosity. [Pg.450]

Natural Gums. These were used in early styling products, formerly called wave sets. Natural gums generally make hazy solutions and the dried film tends to flake. For these reasons they are rarely used. Some of these gums, eg, tragacanth and alginates, can create humidity-resistant films and have limited use for specific product concepts. [Pg.453]

Like the natural gums, starches need to be cooked in water to form dispersions for addition to the papermaking system. Various techniques have been developed for cooking starches rapidly (see Starch). In general, anionic starches are used with alum, which aids in starch retention. The cationic and usually the amphoteric starches are self-retaining. [Pg.19]

Benzoic acid in the free state, or in the form of simple derivatives such as salts, esters, and amides, is widely distributed in nature. Gum benzoin (from styrax ben in) may contain as much as 20% benzoic acid in the free state or in combinations easily broken up by heating. Acaroid resin (from anthorrhoca haslilis) contains from 4.5 to 7%. Smaller amounts of the free acid are found in natural products including the scent glands of the beaver, the bark of the black cherry tree, cranberries, pmnes, ripe cloves, and oil of anise seed. Pern and Tolu balsams contain benzyl benzoate the latter contains free benzoic acid as well. The urine of herbivorous animals contains a small proportion of the glycine derivative of benzoic acid, hippuric acid [495-69-2] (CgH CONHCH2COOH). So-called natural benzoic acid is not known to be available as an item of commerce. [Pg.52]

HEC is generally compatible with other ceUulosic water-soluble polymers to give clear, homogeneous solutions. When mixed with an anionic polymer such as CMC, however, interactions between the two polymers may result in synergistic behavior, ie, viscosities higher than predicted and calculated. HEC has excellent compatibiUty with natural gums. [Pg.274]

Pentachloroethane is a good solvent for cellulose acetate, certain cellulose ethers, and for natural gums and resins, but its high toxicity has discouraged these uses. Pentachloroethane is still used as an intermediate in some tetrachloroethylene processes. [Pg.15]

To prepare stable emulsions ia this way gelation of the continuous medium is necessary. The appearance of a Hquid emulsion may be retained by choosing a polymer for the continuous phase, giving a thixotropic solution with short breakdown and buildup times. The polymers used for this purpose are natural gums (qv) or synthetic polymers. Clay particles also act as viscosity enhancers. The members of the bentonite family derived from... [Pg.198]

Naturgummi, n. natural gum natural rubber, naturbatt, a, naturally hard (of steel) selfhardening. [Pg.314]

Mocak, J. Jurasek, P. Phillips, G.O, Vargas, S. Casadei, E. Ghikamai, B.N. (1998). The classification of natural gums. X. Chemometric characterization of exudate gums that conform to the revised specification of the gum arabic for food use, and the identification of adulterants. Food Hydrocolloids, Vol. 12, No. 2, (April 1998), pp 141-150, ISSN 0268-005X. [Pg.23]

Guhathakurta et al. reported the use of waste natural gum (Bahera) as a MFA in NR and brominated isobutylene-co-paramethyl styrene (BIMS) [38]. The authors found that this renewable material not only acted as an accelerator activator but also as an antioxidant. [Pg.1034]

S. Guhathakurta, S. Anandhan, N.K. Singha, R.N. Chattopadhyay, and A.K. Bhowmick, Waste natural gum as a multifunctional additive in mbber. Journal of Applied Polymer Science, 102, 4S97-4907, 2006. Downloaded from http /www.azom.com/details.asp newsID = 1133. Site accessed on December 6, 2006. Downloaded from bttp //www.toyobo.co.jp/e/seibin/car/torikumi/torikumi.btml. Site accessed on Febmary 26, 2006. [Pg.1040]

The viscosity of natural gums, such as cellulose gums, mannogalactans, seaweed, pectin, locust bean gum, guar gum, and tragacanth has important industrial applications in the food, pharmaceutical, cosmetic, textile, adhesives, and paint fields. The characteristics of viscosity are related to specific uses and to the economics of the process. [Pg.5]

As distinct from the gelling properties of certain natural gums, usually exhibited by structural rigidity, viscosity is a thickening of the aqueous portion of a system by means of particle water absorption, and swelling of the colloid. From a practical angle, it manifests itself by the phenomena of thickening and reduced flow characteristics. [Pg.5]

Some of the principal applications of this increased viscosity of the aqueous medium, due to the swelling of the natural gums, can be broadly classified as follows ... [Pg.5]

Enhancement of the setting characteristics of other natural gums... [Pg.5]

The viscosity function of the natural gums is utilized in both oil in water and water in oil emulsions. Often the gums are referred to as emulsifying agents. They are considered not so much as emulsifiers, but rather as emulsion protectors or stabilizers. To a large extent, the function is to increase the viscosity of the aqueous phase so that it approaches, or slightly exceeds, that of the oil hence, there is less tendency for the two phases, once emulsified, to separate by mechanical slippage. [Pg.8]

Wright, M. and B. Wheals (1987), Pyrolysis-mass spectrometry of natural gums, resins and waxes and its use for detecting such materials in ancient Egyptian cases, /. Appl. Pyrol. 11,195-211. [Pg.626]

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