Paper industry, starch dispersion

Nonfood Uses. Native com starch is principally used in nonfood appHcations in mining, adhesives, and paper industries. Pregelatinized starch is chemically unmodified, but it is physically modified. Pregelatinized starches are used to decrease water losses in oil-weU drilling muds, in cold water-dispersable wallpaper pastes, and in papermaking as an internal fiber adhesive. 

Oxidized Starches. Alkaline hypochlorite treatment introduces carboxyl and carbonyl groups, effects some depolymerization, and produces whiter (bleached) products that produce softer, clearer gels. Ammonium persulfate is used in some paper mills with continuous thermal cookers to prepare in situ bigb solids, low viscosity dispersions. Most of the hypochlorite-oxidized starch and all the ammonium persulfate-oxidized starch is used in the paper industry. The low solution viscosity and good binding and adhesive properties of these products make them especially effective in high solids, pigmented... 

Starch for use in papermaking has to meet specific purity requirements in residual oil, protein, bran and ash content. Industrial starches have a protein content (N X 6.25), ranging from about 0.05% for potato starch to 0.3-0.6% for com starch, depending on separation efficiency during production. Excess protein content will induce foaming in dispersions of starch and affect the quality and strength of the coated surface. Starch for use in the paper industry should not contain more than 0.4% protein. Oxidized starches tend to have the lowest protein content. Residual oil will cause retrogradation due to complex formation with amylose. 

Uses Fertilizer animal feed supplement stabilizer for resins, plastics, explosives softener for cellulose in paper industry deodorizer penetrant cure accelerator and activator airport runway deicing agent dispersant (animal glue, proteins) plasticizer for starch adhesives food additive, yeast nutrient, fermentation aid flour treatment agent diuretic, antiseptic in pharmaceuticals antistat, humectant in cosmetics keratin softenerfor dry skin prods. in ammoniated dentifrices in side seam cements for food-contact containers... 

In the paper industry, the use of polymer dispersions is restricted to surface sizing and paper coating. Surface sizing means hydrophobizing the surface of the paper sheet to reduce its absorbency. Thus is achieved using a formulation that includes preferentially starch and the sizing agents that are... 

For example, starch is the principal water-dispersible natural polymer used industrially as an adhesive and in its many forms it is widely employed in the paper and paper products industry. Poly(vinyl acetate) and its copolymers are synthetic materials and are usually used as aqueous latices. They have found widespread used in the paper industry, where their often superior properties offset their higher price, and are used in bookbinding, milk cartons, envelopes, etc. and are also very familiar as the household white glue for woodworking. 

Functions as an emulsifier of oils and fats in the manufacture of fluid or paste emulsions for industrial lubricants, consumer products, and textile lubricants and softeners. This waxy lipophilic surfactant is also used as a thickening agent and stabilizer for starch coatings on paper, and as a water dispersible paper size. EMEREST 2640 is also a good lubricant for channeling wire through conduit. 

EcoSynthetix markets EcoSphere biolatex binder dispersions as a replacement for petroleum-based styrene butadiene latex. EcoSphere biolatex binders are based on starch derived from crops such as com, potatoes, and tapioca. Although the product was originally developed for the paper coating industry, it can also be applied in the textile coating industry. EcoSynthetix also produces EcoMer , a biobased building block to synthesize waterborne sugar-acrylic adhesives and resins. 

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