Starch as filler

The use of native starch as filler in traditional plastics such as polyolefins nowadays is [12-15] less popular than in the past. Nevertheless, in this paragraph a short review of such kinds of products will be disclosed. 

Parallel to the study of Yu et al. (2009), a bionanocomposite based on glycerol plasticized-pea starch containing ZnO-NP stabilized by soluble starch as filler, was developed by Ma et al. (2009). In this work, the authors showed that the incorporation of this nanofiller led to improvements in the pasting viscosity, storage modulus, glass transition temperature and UV absorbance. In the same way of Yu et al. (2009), the authors attributed the results to the interaction between ZnO-NP and starch matrix. Soluble starch played an important role in the stabilization of the filler and in the fabrication of starch/ZnO-NP composites. The strong interaction between the filler and the matrix contributed to the improvement in the bionanocomposite properties. 

PE/starch films were formulated in US by Otey et al. [53]. They developed a process for extrusion, compounding and blowing of starch as a thermoplastic film at 5-10% moisture. The concept of using com starch as filler to accelerate the degradation process was developed by Griffin in the UK in 1973 [54]. Griffin found that the degradation of starch/LDPE... 

Griffin [1, 2] was the first to use starch as filler in synthetic plastics. Polyethylene films containing starch and other items based on this technology are available on the market. In this technology starch addition is restricted to a maximum of 10% by weight. The starch has to be dried to under 1% moisture to avoid steam formation during extrusion processes, and the starch granules are surface-treated (with silanes, for example) to increase the compatibility of the hydrophilic starch with the hydrophobic plastic matrix. 

Starches are added to processed meats—lunch meats, hot dogs, sausages, etc.—as fillers, binders, moisture retainers, and fat substitutes. They are added to soups, sauces, and gravies as thickeners. They are used in extruded cereals and snacks to hold the shape of the material. 

Among the naturally occurring filler materials are cellulosics such as wood flour, a-cellulose, shell flour, and starch, and proteinaceous fillers such as soybean residues. Approximately 40,000 t of cellulosic fillers are used annually by the U.S. polymer industry. Wood flour, which is produced by the attrition grinding of wood wastes, is used as filler for phenolic resins, urea resins, polyolefins, and PVC. Shell flour, which lacks the fibrous structure of wood flour, has been used as a replacement for wood flour for some applications. 

Rubber is vulcanised by treatment with sulphur chloride or by heating with sulphur. In most cases, however, rubber articles are made, not of pure vulcanised rubber, but of the latter mixed with various other substances, organic and inorganic. The organic substances more commonly used are brown and white factis, fatty oils, oxidised oils, waxes, mineral oils, paraffin wax or ceresine, resin or resin oils, bitumens, tar, pitch, starch, and artificial dyes. Very many inorganic compounds may be added either as fillers or to give colour, e.g., talc, kaolin, asbestos, chalk, gypsum, lime. 

Cationic starches are widely used as wet-end additives in the pulp and paper industry to enhance starch and filler retention during papermaking. Use of cationic starches increases paper strength and decreases biological oxygen demand (BOD) of paper mill effluent. Presently only cationic corn and potato starches are used by Canadian paper mills. The degree of substitution (DS) of normal, waxy, high-amylose barley... 

Since starch is biodegradable, it has found use as filler in polymers, such as extruded films applied to paperboard for use in packaging.295,296 The starch is incorporated in granular form,297 as an octenylsuccinate derivative298 and in other forms. Starch-based blown films are prepared from starch-poly(ethylene-co-acrylic acid) formulations.299... 

In the present experiment, we measure the amount of the active ingredient, acetylsalicylic acid (see also Experiment 35), in common aspirin pills. Companies use different fillers and in different amounts, but the active ingredient, acetylsalicylic acid, must be the same in every aspirin tablet. We separate the acetylsalicylic acid from the filler based on their different solubilities. Acetylsalicylic acid is very soluble in ethanol, while neither starch, nor other polysaccharides, or even mono- and disaccharides used as a fillers, are soluble in ethanol. Some companies may use inorganic salts as fillers but these too are not soluble in ethanol. On the other hand, some specially formulated aspirin tablets may contain small amounts of ethanol-soluble substances such as stearic acid or vegetable oil. Thus the ethanol extracts of aspirin tablets may contain small amounts of substances other than acetylsalicylic acid. 

A large number of inorganic and organic substances are used as fillers in polymer composites. Calcium carbonate, barium sulfate, clays, silica, and talc are common examples. Glass beads are often used in traffic paints to increase reflectivity. Metal fibers are sometimes added to impart conductivity or to improve metal plating. A number of organic materials are also used, including wood flout cellulose, and even corncobs. We will encounter starch/ ... 

In nature, starch is based on crystalline beads of about 15-100 microns in diameter. Crystalline starch beads in plastics can be used as fillers or can be transformed into thermoplastic starch, which can either be processed alone or in combination with specific synthetic polymers. To make starch thermoplastic, its crystalline structure has to be destroyed by pressure, heat, mechanical work or use of plasticisers. Three main families of starch polymer can be used pure starch, modified starch and fermented starch polymers. 

Tablet diluent Inert substance used as filler to create desired bulk, flow properties, and compression characteristics in preparation of tablets Dibasic calcium phosphate, kaolin, lactose, mannitol, microcrystalline cellulose, powdered cellulose, precipitated calcim carbonate, sorbitol, starch...

Tablets [16,17]. Tablets are the most popular type of dosage form, since they offer convenience, stability, accuracy and precision, and bioavailability of the active ingredients [17]. Tablets are prepared by combining the active ingredient with a filler, such as sugar or starch, and a binder, such as corn syrup or starch. The filler is added to ensure that...

Lerk, C.F. Arends-Scholte, A.W. Bergsma, J. Eissens, A.C. Ramaker, J. te Wierik, G.H.P. High surface area starch products as filler-binder in direct compression tablets. Pharmazie 1996, 51, 311-315. 

Starch and cellulosic materials are frequently used as fillers in degradable materials. The addition of starch to LDPE in combination with a pro-oxidant increases the photooxidation rate and the formation of hydroperoxides and carbonyl groups. Starch alone does not increase the photooxidation rate. The addition of starch to LDPE increases its stability in 80°C water. Slower degradation in water is due to leaching out of the pro-oxidant. The addition of starch causes biodegradation process under soil burial conditions. Further increase in the degradation rate can be achieved by preheating polyethylene filled with starch. ... 

Starch phosphates have been also proposed as additives for oil-well drilling muds.1636,1637 Starch phosphonate ethers were also suggested as fillers, binders, flocculants and sizes.1585... 

The number of chemicals used to maintain the balance on the paper machine of both process chemicals, e.g. three or four component retention aids, deposit control chemicals as well as defoamers and anionic trash catchers (ATC) and performance chemicals, e.g. cationic starch, size, filler and perhaps wet strength resin and/or dye, has resulted in a wet-end soup . 

Uncooked starch slurries are sometimes added at the wet-end, intending that the starch cooks in the dryer section. This procedure is satisfactory only if the temperature of the web is high enough to gelatinise the starch granules in situ, otherwise no value is derived from the uncooked starch granules they merely act as filler and lower the strength of the paper [3]. 

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