Tygogal EPA has classified acrylamide as a probable human carcinogen. Formation of 3-chloropropane-1, 2-diol in systems simulating processed foods. Tumors of the brain and spinal cord were also seen in studies, but they did not show clear dose responses and did not attain statistical significance. The researchers have also produced a new variety of potato through genetic modification that contains lower sugar levels than conventional potatoes and are targeting plant genes responsible for controlling asparagine levels in an effort to reduce acrylamide levels in food crops. So although there is no conclusive evidence that acrylamide is carcinogenic in humans, it is sensible to be aware of levels, limit where possible, and ensure other dietary and lifestyle guidelines are followed to remain healthy.
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Physicochemical properties[ edit ] Linear polyacrylamide is a water-soluble polymer. It is typically non-ionic polymer but due to hydrolysis of some amide groups they could convert into carboxylic groups giving polyacrylamide some weak an ionic properties. Uses of polyacrylamide[ edit ] One of the largest uses for polyacrylamide is to flocculate solids in a liquid. This process applies to water treatment , and processes like paper making and screen printing. Polyacrylamide can be supplied in a powder or liquid form, with the liquid form being subcategorized as solution and emulsion polymer.
Another common use of polyacrylamide and its derivatives is in subsurface applications such as Enhanced Oil Recovery. High viscosity aqueous solutions can be generated with low concentrations of polyacrylamide polymers, and these can be injected to improve the economics of conventional waterflooding.
The linear soil conditioning form was developed in the s by Monsanto Company and was marketed under the trade name Krilium. The soil conditioning technology was presented at a symposium on "Improvement of Soil Structure" held in Philadelphia, Pennsylvania on December 29, The technology was strongly documented and was published in the June issue of the journal Soil Science, volume 73, June that was dedicated to polymeric soil conditioners.
The original formulation of Krilium was difficult to use because it contained calcium which cross-linked the linear polymer under field conditions. Even with a strong marketing campaign, Krilium was abandoned by Monsanto. After 34 years, the journal Soil Science wanted to update the soil conditioning technology and published another dedicated issue on polymeric soil conditioner and especially linear, water-soluble, anionic polyacrylamide in the May issue, volume , issue number 5.
Nelson from BYU stated in part: The new water-soluble soil conditioners may, if used according to established procedures increase pore space in soils containing clay increase water infiltration into soils containing clay prevent soil crusting stop erosion and water runoff make friable soil that is easy to cultivate make soil dry quicker after rain or irrigation, so that the soil can be worked sooner Consequently, these translate into stronger, larger plants with more extensive root system earlier seed emergence and crop maturity more efficient water utilization more response to fertilizers and to new crop varieties less plant diseases related to poor soil aeration decreased energy requirement for tillage The cross-linked form which retains water is often used for horticultural and agricultural under trade names such as Broadleaf P4, Swell-Gel, and so on.
The anionic form of linear, water-soluble polyacrylamide is frequently used as a soil conditioner on farm land and construction sites for erosion control , in order to protect the water quality of nearby rivers and streams.
Similarly, the absorbent properties of one of its copolymers can be utilized as an additive in body-powder. The ionic form of polyacrylamide has found an important role in the potable water treatment industry. Trivalent metal salts, like ferric chloride and aluminum chloride , are bridged by the long polymer chains of polyacrylamide. This results in significant enhancement of the flocculation rate. This allows water treatment plants to greatly improve the removal of total organic content TOC from raw water.
Polyacrylamide is also often used in molecular biology applications as a medium for electrophoresis of proteins and nucleic acids in a technique known as PAGE. It was also used in the synthesis of the first Boger fluid. Molecular biology laboratories[ edit ] Polyacrylamide was first used in a laboratory setting in the early s. In , the groups of Davis and Ornstein  and of Raymond and Weintraub  independently published on the use of polyacrylamide gel electrophoresis to separate charged molecules.
Acrylamide has many other uses in molecular biology laboratories, including the use of linear polyacrylamide LPA as a carrier , which aids in the precipitation of small amounts of DNA. Many laboratory supply companies sell LPA for this use.
As an nonionic monomer it can be co-polymerize with anionic for example Acrylic acid and cationic monomer such as diallyldimethyl ammonium chloride DADMAC and resulted co-polymer that can have different compatibility in different applications. Soil conditioner[ edit ] The primary functions of polyacrylamide soil conditioners are to increase soil tilth, aeration, and porosity and reduce compaction, dustiness and water run-off.
Secondary functions are to increase plant vigor, color, appearance, rooting depth and emergence of seeds while decreasing water requirements, diseases, erosion and maintenance expenses. FC is used for this purpose. Stability[ edit ] In dilute aqueous solution, such as is commonly used for Enhanced Oil Recovery applications, polyacrylamide polymers are susceptible to chemical, thermal, and mechanical degradation.
Chemical degradation occurs when the labile amide moiety hydrolyzes at elevated temperature or pH, resulting in the evolution of ammonia and a remaining carboxyl group. Thus, the degree of anionicity of the molecule increases. Thermal degradation of the vinyl backbone can occur through several possible radical mechanisms, including the autooxidation of small amounts of iron and reactions between oxygen and residual impurities from polymerization at elevated temperature.
Mechanical degradation can also be an issue at the high shear rates experienced in the near-wellbore region. Environmental effects[ edit ] Concerns have been raised that polyacrylamide used in agriculture may contaminate food with acrylamide , a known neurotoxin and carcinogen. In a study conducted in at the Central Science Laboratory in Sand Hutton , England , polyacrylamide was treated similarly as food during cooking. It was shown that these conditions do not cause polyacrylamide to de-polymerise significantly.
Consumers are encouraged to monitor their intake of acrylamide. It also forms the basis for the generation of polyacrylamide, which has a variety of applications, including wastewater treatment and gel electrophoresis for laboratory research. Current concern regarding acrylamide in food has resulted from an increased awareness of its presence in food and from current research identifying how it is formed in food and how its formation can be reduced. Fill out the form below to receive a free trial or learn more about access: It is also used in the synthesis of dyes, as a cross-linking agent, in soil conditioning agents, in flocculants, in sewage and waste treatment, in ore processing, in adhesives, in paper and textile coatings, and in permanent press fabrics. Please akri,amid your Internet connection and reload this page.
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