AMPS (2-Acryloylamino-2-methylpropane-1-sulfonic acid)
CAS Number:15214-89-8 ; 2-Acryloylamino-2-methylpropane-1-sulfonic acid; 2-Acrylamido-2-methylpropane sulfonic acid; 2-Acrylamido-2-methylpropanesulfonic acid; 2-Acrylamido-2-methyl-1-propane sulfonic acid. 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.
2-Acrylamido-2-methylpropane sulfonic acid (AMPS) was a Trademark name by The Lubrizol Corporation. It 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.
Production
AMPS is made by the Ritter reaction of acrylonitrile and isobutylene in the presence of sulfuric acid and water. The recent patent literature describes batch and continuous processes that produce AMPS in high purity (to 99.7%) and improved yield (up to 89%, based on isobutene) with the addition of liquid isobutene to an acrylonitrile / sulfuric acid / phosphoric acid mixture at 40C.
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: >100
N-Methyl-2-pyrrolidone: 80
Methanol: 8.7
Inhibition of divalent cation precipitation: Sulfonic acid in AMPS is a 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.
Applications
Acrylic fiber: A number of enhanced performance characteristics are imparted to acrylic, modified-acrylic, polypropylene and polyvinylidene fluoride fibers: dye receptivity, moisture absorbency, and static resistance.
Coating and adhesive: Its 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.It improves the thermal and mechanical properties of adhesives, and increases the adhesive strength of pressure-sensitive adhesive formulations.
Detergents: Enhances the washing performance of surfactants by binding multivalent cations and reducing dirt attachment.
Personal care: Strong polar and hydrophilic properties introduced to a high molecular weight AMPS homopolymer are exploited as a very efficient lubricant 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, defibrillation electrode, electrosurgical grounding pads, and iontophoretic drug delivery electrodes.In addition, polymers derived from AMPS are used as the absorbing hydrogel and the tackifier component of wound dressings.Is used due to its high water absorption and retention capability as a monomer in superabsorbents e. g. for baby diapers.
Oil field applications: Polymers in oil field 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,[27] 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 treatment 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.
Crop protection: increases in dissolved and nanoparticulatepolymer formulations bioavailability of pesticides in aqueous-organic formulations.
Membranes: It increases water flow, retention and fouling resistance of asymmetric ultrafiltration and microfiltration membrane and is being studied as an anionic component in polymer fuel cell membranes.
Construction applications: Superplasticizers with AMPS are used to reduce water in concrete 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 agglomeration 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 lime on concrete surface and improve the appearance and durability of coating.
Usage:
In the structure of the AMPS there are strong anion and water-soluble sulfur group, shield the amide group and the unsaturated double bond, these make the 2-AMPS-A have the excellent performance. The 2-AMPS-A has the excellent synthesis、adsorptivity、biological activity、surface activity、hydrolytic stability and thermal stability. It can be used in co-polymerization and in addition reaction, it is widely used in water treatment 、oilfield chemicals、chemical fiber、water absorbent material、plastics、paper making、spinning、printing and dyeing、biomedicine、magnetic material and makeup etc.
Water treatment: The 2-AMPS-A monomer homopolymer with the acrylamide 、acrylic acid monomer homopolymer, they could be sludge dehydrating agent in the sewage purification process and preservative of the iron 、zinc、aluminum、cooper、alloy in the closed water circulation system, they also could be used as cleaning and scale inhibitor of heater 、cooling tower、air cleaner、gas-cleaner.
Oilfield chemistry: This product develops rapidly in the application of the oil field chemistry. The scope includs oil well cement admixtures、drilling fluid additive、acidizing fluid、well completion fluid、work over fluid、fracture fluid.
Synthetic fibre: The 2-AMPS-A is the important monomer which could improve the combination property of some synthetic fibre, in particular, the orion and the modacrylic fiber with chloride, the dosage is the 1%-4% of the fiber, it could improve the white content、dyeing property、antistatic、ventilation property and flame resistance.
The application for the textile: The copolymer of the acrylamide-2-methylpropane sulfonic acid 、ethyl acetate and acrylic acid, it is the ideal size of the cotton and the polyester blend fabric, it has the characteristic of easy to use and easy to remove by water.
Paper making: The copolymer of the acrylamide-2-methylpropane sulfonic acid with other water-soluble monomer, this is the indispensable chemical in all kinds of paper making factory, it could be used as the drainage aid and on gel, it could increase the strength of the paper, it also could be used as the pigment dispersing agent of color coating.
AMPS (2-Acrylamido-2-methylpropane sulfonic acid); CAS: 15214-89-8
2-Acrylamide-2-methylpropanesulfonic acid
SynonymsAMPS;TBAS;ampsna;TBAS-Q;AMPS MONOMER;Lubrizol AMPS;P(DMDAAC/AM/AMPS);ACRYLAMIDO BUFFER;2-Acrylamide-2-methy;LABOTEST-BB LT00012662
CBNumber:CB3470952
Molecular Formula:C7H13NO4S
Formula Weight:207.25
2-Acrylamide-2-methylpropanesulfonic acid Properties
Melting point:195-200 C (dec.)(lit.)
Density:1.45
vapor pressure :