Paper adhesive starch

Amylopectin is the polymeric component of starch and consists mainly of glucose units joined at the 1,4-positions. Relative molar mass tends to be very high, e.g. between 7 and 70 million. A variety of modified starches are used commercially which are produced by derivatisation to give materials such as ethanoates (acetates), phosphates, and hydroxyalkyl ethers. Modified and unmodified starches are used in approximately equal tonnages, mainly in papermaking, paper coatings, paper adhesives, textile sizes, and food thickeners. 

In the manufacture of paper, starch-based adhesives are used either to strengthen the paper base or for coating the surface of the paper. Raw starch is unsuitable for either purpose. To achieve sufficient adhesive power with raw starch would require the application of a solution that was far too thick for practical use. Instead, chemically modified starch, with a much lower viscosity in solution, is used. As an economical alternative to modifying the starch with aggressive oxidizing agents, the starch can be treated with enzymes ( df-amylases) to obtain the same thinning effect... 

Reaction of starch with polyphosphates or phosphorus containing reagents, which is utilized in paper, adhesives, and textiles. 

Dispersions of starch in dimethyl sulfoxide become stiff within 20 min when brought into contact with water.2684 Sulfonium salts can be produced by the reaction of reagents already bearing the sulfonium moiety, as when starch is treated with 2-chloroethylmethylethyl sulfonium iodide in the presence of calcium hydroxide.2685 The resulting formulations can be applied as paper coatings, paper adhesives, sizes, and thickeners.2685,2686... 

Two types of traditional sizes, namely starch and glue (protein), can be tested for, and the tests are also used for identification of adhesives on paper artefacts. Starch can be detected by placing a drop of iodine solution onto the area to be tested, and a blue-black colouration reveals the presence of starch. There are many tests for protein, but in the ninhydrin test a solution of ninhydrin in methyl Cellosolve with a trace of surfactant is added to the paper that is then heated in an oven at 100°C. A purplish stain indicates the presence of protein. 

CAS 533-74-4 EINECS/ELINCS 208-576-7 Uses Preservative for coatings, slurries, adhesives, starch- and casein-based systems recirculating water systems food pkg. adhesives slimicide in food-contact paper Features Esp. effective at pH > 7 Regulatory EDA 21 CER 175.105,176.230,176.300 Properties Powd. 

Starches are modified chemically in various ways. Some acetate and phosphate esters are produced commercially, as well as hydroxyalkyl and tertiary aminoalkyl ethers. Both unmodified and modified starches are used principally in paper making, paper coating, paper adhesives, textile sizes, and as food thickeners. There are many reports in the literature on graft copolymers of starch. The work is often conducted is search of biodegradable materials for packaging and agricultural mulches. Most chemical modifications of starch parallel those of cellulose. 

Unmodified starch and modified starches find approximately equal tonnage usage. These materials are used principally in paper-making, paper coatings, paper adhesives, textile sizes and food thickeners. 

The main prodnct ftom these crops is indnstrial starch used in many different ways. These inclnde packaging, coatings for textiles and paper, adhesives, explosives, cosmetics, plastics and, of conrse, bioethanol which has already been covered elsewhere in this chapter. 

In making paper sacks, starch-based adhesives normally are used for the longitudinal seam and also for the bottom and bottom patching. For paper sacks with PE free film or inliner, emulsion-based synthetic resin adhesives are used. For the longitudinal seam of the inliner, hot-melt adhesives are used. 

Paper Adhesives, Liquid. Liquid paper adhesives are used in the household for gluing paper and cardboard. These mostly solvent-free adhesives are partly based on natural raw materials such as dextrin, starch, and cellulose derivatives (pastes). They are sold in bottles and tubes but also as pens. 

Wheat starch Australia, EU/Europe, Japan sweeteners, bakery products, food industry, paper, adhesives. 

Starch is insoluble in cold water, but in hot water the granules gelatinize to form an opalescent dispersion. It is made from corn, wheat, potatoes, rice and other cereals by various physical processes such as steeping, milling and sedimentation. It is used as an adhesive, for sizing paper and cloth, as an inert diluent in foods and drugs, and for many other purposes. 

Synthetic emulsion polymers account for approximately 70% of the U.S. consumption of acrylate monomers. Major end uses for these latex polymers are coatings (32%), textiles (17%), adhesives (7%), paper (5%), and floor poHshes (3%). The U.S. producers of acryflc copolymer emulsions include Rohm and Haas, Reichhold, National Starch, Union Carbide, Air Products, Unocal, B. F. Goodrich, and H. B. Fuller. 

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