Potato-starch-based polymers

Torres et al. (2006) reported a novel microwave processing technique to produce biodegradable scaffolds for tissue engineering from different types of starch-based polymers. Potato, sweet potato, com starch, and non-isolated amaranth and quinoa starch were used along with water and glycerol as plasticizers to produce porous stmctures. Figure 16.1 shows the manufacturing procedure of microwaved starch scaffolds. 

In nature, the availability of starch is just second to cellulose. The most important industrial sources of starch are corn, wheat, potato, tapioca and rice. In the last decade, there has been a significant reduction in the price of corn and potato starch, both in Europe and the USA. The lower price and greater availability of starch associated with its very favourable environmental profile aroused a renewed interest in development of starch-based polymers as an alternative to polymers based on petrochemicals. 

Starch-based polymers can be based on crops such as com (maize), wheat, or potatoes. Starch content may range from 10% to >90%, but significant material breakdown occurs above 60%. As the starch content increases, the polymer compos-... 

Talja RA, Helen H, Roos YH, Jouppila K (2007) Effect of various polyols and polyol contents on physical and mechanical properties of potato starch-based films. Caibohydr Polym 67 288-297 Tam KH, Djurisic AB, Chan CMN, Xi YY, Tse CW, Leung YH, Chan WK, Leung FCC (2008) Antibacterial activity of ZnO nanorods prepared by a hydrothermal method. Thin Solid Films 516 6167-6174... 

Starch-based polymers can be produced from potato, com, wheat, cassava, or tapioca. In the United States and Europe, com starch is the predominate source for starch-based polymers. Corn starch is mostly used for animal feed. Starch-based polymers can be processed on traditional thermoplastic forming operations of injection molding, extmsion, blow molding, compression molding, rotational molding, etc. Starch can be made from corn or vegetable oils and other renewable sources. The most common plasticizers for starch are water and glycerol. 

Silva et al. (2006) studied starch-based microparticles as a novel strategy for tissue engineering applications. They developed starch-based microparticles, and evaluated them for bioactivity, cytotoxicity, ability to serve as substrates for cell adhesion, as well as their potential to be used as delivery systems either for anti-inflammatory agents or growth factors. Two starch-based materials were used for the development of starch-based particulate systems (1) a blend of starch and polylactic acid (SPLA) (50 50 w/w) and (2) a chemically modifled potato starch, Paselli II (Pa). Both materials enabled the synthesis of particulate systems, both polymer and composite (with BG 45S5). A simple solvent extraction method was employed for the synthesis of SPLA and SPLA/BG microparticles, while for Pa and Pa/BG... 

The characteristics of the developed material demonstrate that pure potato starch can be used for the production of foams without the need of modified starches or blends with other additives or polymers. This will make new applications for thermoplastic starch based foams possible. 

Additive-based biodegradable materials usually incorporate a natural degradable polymer, such as com, rice, or potato starch, with a nonbiodegradable synthetic polymer, such as polyethylene, polypropylene, polystyrene, or polyurethane. It generally requires an accelerator additive to facilitate the breakdown of the polymer chain to the point at which it can be metabolized by microorganisms. 

Similar to the PLA and/or PCL HMA, the natural polymer based HMA can also be applied in packaging. Saara Inkinen et al. [81] discussed the stability of blends of a lactic acid-based hot melt adhesive (LHM), oxidized potato starch (dried or nondried) and polyethylene glycol (PEG). Table 6.4 shows the stress and strain at maximum load values of the samples, and Figs. 6.12, 6.13 and 6.14 are several test results. The test results suggest that the HMA can meet the requirements for packaging. Blumenthal et al. [95] successhilly prepared a... 

Russell PL (1987) Gelatinisation of starches of different amylose/amylopectin content A study by differential scanning calorimetry. J Cereal Sci 6 133-145 Sadegh-Hassani F, Nafchi AM (2014) Preparation and characterization of bionanocomposite films based on potato starch/halloysite nanoclay. Int J Biol Macromol 67 446 58 Salman H, Blazek J, Lopez-Rubio A, Gilbert EP, Hanley T, Copeland L (2009) Stmcture-function relationships in A and B granules from wheat starches of similar amylose content Carbohydr Polym 75 420-427... 

Starch is a unique bio-based polymer which occurs in nature as energy storage granules. Starch is a natural polysaccharide abundantly available in nature from various botanical sources including wheat, rice, com, and potato. Its chemical... 

Cinelli, P., Chiellini, E., Lawton, J. W., and Imam, S. H. 2006. Foamed articles based on potato starch, corn fibers and poly (vinyl alcohol). Polymers Degradation and Stability 91 1147-1155. 

There have been several applications of IGC to the determination of sur ce interactions (15-24). In particular, IGC was applied to several studies of natural polymers. Among them are cellulose (2, wood (26), potato starch as Amylopectin (27) and lignocellosic surfaces (2S). In these studies, die surface diermodynamic characteristic of wood fiber and its relationship to the fiber s water vapor adsorption was determined by IGC (26) Also, the surface ener, surface acid-base flee energy, enthalpy of desorption of acid-base probes, surface acid-base acceptors, and donor parameters were determined by IGC (26). Cellulose was also found by IGC to be sensitive to the presence of adsorbed water which possibly disorders its surface structure. 

Carbohydrate-based replacements rely on a viscosity increase and smooth gel-like textures to simulate the properties of fats and oils. These substitutes include gums, hydrophilic hydrocolloids that increase product viscosity and improve emulsion stability polydextrose, a polymer of dextrose with small amounts of sorbitol and citric acid made by Pfizer Chemical Division, New York and a variety of com, tapioca and potato starch maltodextrins made by various starch processors. Neither the protein- nor the carbohydrate-based replacements can be used as frying or dry coating oils. 

Starch is a polysaccharide found in many plant species. Com and potatoes are two common sources of industrial starch. The composition of starch varies somewhat in terms of the amount of branching of the polymer chains (11). Its principal use as a flocculant is in the Bayer process for extracting aluminum from bauxite ore. The digestion of bauxite in sodium hydroxide solution produces a suspension of finely divided iron minerals and siUcates, called red mud, in a highly alkaline Hquor. Starch is used to settle the red mud so that relatively pure alumina can be produced from the clarified Hquor. It has been largely replaced by acryHc acid and acrylamide-based (11,12) polymers, although a number of plants stiH add some starch in addition to synthetic polymers to reduce the level of residual suspended soHds in the Hquor. Starch [9005-25-8] can be modified with various reagents to produce semisynthetic polymers. The principal one of these is cationic starch, which is used as a retention aid in paper production as a component of a dual system (13,14) or a microparticle system (15). 

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