2-Acrylamido-2-methylpropane sulfonic acid
Encyclopedia
2-Acrylamido-2-methylpropane sulfonic acid (AMPS) is a reactive, hydrophilic, sulfonic acid acrylic monomer
used to alter the chemical properties of wide variety of anionic polymers. In the 1970s, the earliest patents using this monomer were filed for acrylic fiber manufacturing. Today, there are over several thousands patents and publications involving use of AMPS in many areas including water treatment
, oil field
, construction chemicals, hydrogels for medical applications, personal care products, emulsion
coatings, adhesives, and rheology modifiers.
of acrylonitrile
and isobutylene
in the presence of very strong sulfonic acids and water.
Monomer
A monomer is an atom or a small molecule that may bind chemically to other monomers to form a polymer; the term "monomeric protein" may also be used to describe one of the proteins making up a multiprotein complex...
used to alter the chemical properties of wide variety of anionic polymers. In the 1970s, the earliest patents using this monomer were filed for acrylic fiber manufacturing. Today, there are over several thousands patents and publications involving use of AMPS in many areas including water treatment
Water treatment
Water treatment describes those processes used to make water more acceptable for a desired end-use. These can include use as drinking water, industrial processes, medical and many other uses. The goal of all water treatment process is to remove existing contaminants in the water, or reduce the...
, oil field
Oil field
An oil field is a region with an abundance of oil wells extracting petroleum from below ground. Because the oil reservoirs typically extend over a large area, possibly several hundred kilometres across, full exploitation entails multiple wells scattered across the area...
, construction chemicals, hydrogels for medical applications, personal care products, emulsion
Emulsion
An emulsion is a mixture of two or more liquids that are normally immiscible . Emulsions are part of a more general class of two-phase systems of matter called colloids. Although the terms colloid and emulsion are sometimes used interchangeably, emulsion is used when both the dispersed and the...
coatings, adhesives, and rheology modifiers.
Production
AMPS is made by the Ritter reactionRitter reaction
The Ritter reaction is a chemical reaction that transforms a nitrile into a N-alkyl amide using various alkylating reagents, for example, strong acid and isobutylene....
of acrylonitrile
Acrylonitrile
Acrylonitrile is the chemical compound with the formula C3H3N. This pungent-smelling colorless liquid often appears yellow due to impurities. It is an important monomer for the manufacture of useful plastics. In terms of its molecular structure, it consists of a vinyl group linked to a nitrile...
and isobutylene
Isobutylene
Isobutylene is a hydrocarbon of significant industrial importance. It is a four-carbon branched alkene , one of the four isomers of butylene. At standard temperature and pressure it is a colorless flammable gas.-Uses:...
in the presence of very strong sulfonic acids and water.
Properties
- Hydrolytic and thermal stability: The geminal dimethyl group and the sulfomethyl group combine to sterically hinder the amide functionality and provide both hydrolytic and thermal stabilities to AMPS-containing polymers.
- Polarity and hydrophilicity: The sulfonate group gives the monomer a high degree of hydrophilicity and anionic character at wide range of pH. In addition, AMPS is absorbing water readily and also imparts enhanced water absorption and transport characteristics to polymers.
- Solubility: AMPS is very soluble in water and dimethylformamide (DMF) and also shows limited solubility in most polar organic solvents.
| Solvent | Solubility (gAMPS/100 g solvent) |
|---|---|
| Water | 150 |
| Dimethylformamide Dimethylformamide Dimethylformamide is an organic compound with the formula 2NCH. Commonly abbreviated as DMF , this colourless liquid is miscible with water and the majority of organic liquids. DMF is a common solvent for chemical reactions... |
>100 |
| N-Methyl-2-pyrrolidone | 80 |
| Methanol Methanol Methanol, also known as methyl alcohol, wood alcohol, wood naphtha or wood spirits, is a chemical with the formula CH3OH . It is the simplest alcohol, and is a light, volatile, colorless, flammable liquid with a distinctive odor very similar to, but slightly sweeter than, ethanol... |
8.7 |
- Inhibition of divalent cation precipitation: Sulfonic acid in AMPS is very strong ionic group and ionizes completely in aqueous solutions. In applications where the precipitation of mineral salts is undesirable, the incorporation of a polymer containing even a small quantity of AMPS can significantly inhibit the precipitation of divalent cations. The result is a significant reduction in the precipitation of a wide variety of mineral salts, including calcium, magnesium, iron, aluminum, zinc, barium and chromium.
- Determining viscosity-average molecular weight (Mark-Houwink constants)
Na-AMPS 0.01N 0.05N 0.1N 0.5N 1.0N 5.0N K x 105 0.67 1.47 1.67 1.32 3.34 5.01 ν 1.02 0.91 0.88 0.86 0.77 0.72
- Reactivity ratio: AMPS reacts well with a variety of vinyl monomers. M2= AMPS or † sodium salt of AMPS
M1 r1 r2 Remark Acrylonitrile AcrylonitrileAcrylonitrile is the chemical compound with the formula C3H3N. This pungent-smelling colorless liquid often appears yellow due to impurities. It is an important monomer for the manufacture of useful plastics. In terms of its molecular structure, it consists of a vinyl group linked to a nitrile...1.2 0.7 DMF DimethylformamideDimethylformamide is an organic compound with the formula 2NCH. Commonly abbreviated as DMF , this colourless liquid is miscible with water and the majority of organic liquids. DMF is a common solvent for chemical reactions...Acrylic acid Acrylic acidAcrylic acid is an organic compound with the formula CH2=CHCO2H. It is the simplest unsaturated carboxylic acid, consisting of a vinyl group connected directly to a carboxylic acid terminus. This colorless liquid has a characteristic acrid or tart smell. It is miscible with water, alcohols,...0.74 0.19 Water, pH=7.0 Acrylic acid Acrylic acidAcrylic acid is an organic compound with the formula CH2=CHCO2H. It is the simplest unsaturated carboxylic acid, consisting of a vinyl group connected directly to a carboxylic acid terminus. This colorless liquid has a characteristic acrid or tart smell. It is miscible with water, alcohols,...1.58 0.11 Water, pH=2~4 Itaconic acid Itaconic acidItaconic acid, or methylenesuccinic acid, is an organic compound. Itaconic acid is a white crystalline powder. Itaconic acid is a naturally occurring compound, non-toxic, and readily biodegradable. The name itaconic was devised as an anagram of aconitic.Historically, itaconic acid was obtained by...0.46 0.04 DMF DimethylformamideDimethylformamide is an organic compound with the formula 2NCH. Commonly abbreviated as DMF , this colourless liquid is miscible with water and the majority of organic liquids. DMF is a common solvent for chemical reactions...
, 70°C, Benzoyl PeroxideBenzoyl peroxideBenzoyl peroxide is an organic compound in the peroxide family. It consists of two benzoyl groups bridged by a peroxide link. Its structural formula is [C6H5C]2O2. It is one of the most important organic peroxides in terms of applications and the scale of its production...Acrylamide AcrylamideAcrylamide is a chemical compound with the chemical formula C3H5NO. Its IUPAC name is prop-2-enamide. It is a white odourless crystalline solid, soluble in water, ethanol, ether, and chloroform. Acrylamide is incompatible with acids, bases, oxidizing agents, iron, and iron salts...0.98 0.49 † Water, K2S2O8 Styrene 1.13 0.31 DMF DimethylformamideDimethylformamide is an organic compound with the formula 2NCH. Commonly abbreviated as DMF , this colourless liquid is miscible with water and the majority of organic liquids. DMF is a common solvent for chemical reactions...
, 60°C, AIBNVinyl Acetate Vinyl acetateVinyl acetate is an organic compound with the formula CH3COOCH=CH2. A colorless liquid with a pungent odor, it is the precursor to polyvinyl acetate, an important polymer in industry.-Production:...0.05 11.60 † Methanol MethanolMethanol, also known as methyl alcohol, wood alcohol, wood naphtha or wood spirits, is a chemical with the formula CH3OH . It is the simplest alcohol, and is a light, volatile, colorless, flammable liquid with a distinctive odor very similar to, but slightly sweeter than, ethanol...
, 60°C,N-Vinylpyrrolidone N-VinylpyrrolidoneN-Vinylpyrrolidone is a colorless to yellowish liquid, with a characteristic odor. It is miscible in water and organic solvents. It is the precursor to polyvinylpyrrolidone , an important synthetic material. The NVP monomer is commonly used as a reactive diluent in ultraviolet and electron-beam...0.13 0.66 † 60°C, AIBN 2-Hydroxyethyl methacrylate 0.86 0.90 Water, 60°C, AIBN 2-Hydroxypropyl methacrylate 6.30 0.04 Water, 80°C, (NH4)2S2O8 N,N-Dimethylacrylamide 1.26 0.68 † Water, 30°C, K2S2O8 N-Vinylformamide 0.32 0.39 † VA-044
Applications
- Acrylic fiberAcrylic fiberAcrylic fibers are synthetic fibers made from a polymer with an average molecular weight of ~100,000, about 1900 monomer units. To be called acrylic in the U.S, the polymer must contain at least 85% acrylonitrile monomer. Typical comonomers are vinyl acetate or methyl acrylate...
: A number of enhanced performance characteristics are imparted to acrylic, modified-acrylic, polypropylene and polyvinylidine fluoride fibers: dye receptivity, moisture absorbency, and static resistance.
- Coating and adhesive: Sulfonic acid group gives the monomers ionic character over a wide range of pH. Anionic charges from AMPS fixed on polymer particles enhance the chemical and shear stabilities of polymer emulsion and also reduce the amount of surfactants leaching out of paint film.
- Personal care: Strong polar and hydrophilic properties introduced to a high molecular weight AMPS homopolymer are exploited as a very efficient lubricantLubricantA lubricant is a substance introduced to reduce friction between moving surfaces. It may also have the function of transporting foreign particles and of distributing heat...
characteristic for skin care.
- Medical hydrogel: High water-absorbing and swelling capacity when AMPS is introduced to a hydrogel are keys to medical applications. Hydrogel with AMPS showed uniform conductivity, low electrical impedance, cohesive strength, appropriate skin adhesion, and biocompatible and capable of repeated use and have been used to electrocardiograph (ECG) electrodes, defibrillationDefibrillationDefibrillation is a common treatment for life-threatening cardiac arrhythmias, ventricular fibrillation and pulseless ventricular tachycardia. Defibrillation consists of delivering a therapeutic dose of electrical energy to the affected heart with a device called a defibrillator...
electrode, electrosurgical grounding pads, and iontophoretic drug delivery electrodes. In addition, polymers derived from AMPS are used as the absorbing hydrogel and the tackifierTackifierTackifiers are chemical compounds used in formulating adhesives to increase the tack, the stickiness of the surface of the adhesive. They are usually low-molecular weight compounds with high glass transition temperature...
component of wound dressings.
- Oil field applications: Polymers in oil fieldOil fieldAn oil field is a region with an abundance of oil wells extracting petroleum from below ground. Because the oil reservoirs typically extend over a large area, possibly several hundred kilometres across, full exploitation entails multiple wells scattered across the area...
applications have to stand hostile environments and require thermal and hydrolytic stability and the resistance to hard water containing metal ions. For example, in drilling operations where conditions of high salinity, high temperature and high pressure are present, AMPS copolymers can inhibit fluid loss and be used in oil field environments as scale inhibitors, friction reducers and water-control polymers, and in polymer flooding applications.
- Water treatment applications: The cation stability of the AMPS-containing polymers are very useful for water treatmentWater treatmentWater treatment describes those processes used to make water more acceptable for a desired end-use. These can include use as drinking water, industrial processes, medical and many other uses. The goal of all water treatment process is to remove existing contaminants in the water, or reduce the...
processes. Such polymers with low molecular weights cannot only inhibit calcium, magnesium, and silica scale in cooling towers and boilers, but also help corrosion control by dispersing iron oxide. When high molecular weight polymers are used, they can be used to precipitate solids in the treatment of industrial effluent stream.
- Construction applications: SuperplasticizerSuperplasticizerSuperplasticizers, also known as high range water reducers, are chemicals used as admixtures where well-dispersed particle suspension are required. These polymers are used as dispersants to avoid particle aggregation, and to improve the flow characteristics of suspensions such as in concrete...
s with AMPS are used to reduce water in concreteConcreteConcrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...
formulations. Benefits of these additives include improved strength, improved workability, improved durability of cement mixtures. Redispersible polymer powder, when AMPS is introduced, in cement mixtures control air pore content and prevent agglomerationAgglomerationIn the study of human settlements, an urban agglomeration is an extended city or town area comprising the built-up area of a central place and any suburbs linked by continuous urban area. In France, INSEE the French Statistical Institute, translate it as "Unité urbaine" which means continuous...
of powders during the spray-drying process from the powder manufacturing and storage. Coating formulations with AMPS-containing polymers prevent calcium ions from being formed as limeLime plasterLime plaster is type of plaster composed of hydrated lime, sand and water. Lime plaster is similar to Lime mortar, the main difference is the based on use rather than composition. Traditional lime plaster contains also horse hair to reinforce plaster....
on concrete surface and improve the appearance and durability of coating.