''N'',''N''′-Methylenebisacrylamide (MBAm or MBAA, colloquially "''bis''") is the

organic compound Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...

with the formula CH₂ HC(O)CH=CH₂sub>2. A colorless solid, this compound is a crosslinking agent in

polyacrylamide Polyacrylamide (abbreviated as PAM or pAAM) is a polymer with the formula (-CH2CHCONH2-). It has a linear-chain structure. PAM is highly water-absorbent, forming a soft gel when hydrated. In 2008, an estimated 750,000,000 kg were produced, ...

s, e.g., as used for

SDS-PAGE SDS-PAGE (sodium dodecyl sulfate–polyacrylamide gel electrophoresis) is a Discontinuous electrophoresis, discontinuous electrophoretic system developed by Ulrich K. Laemmli which is commonly used as a method to separate proteins with molecular m ...

Synthesis

Acrylamide Acrylamide (or acrylic amide) is an organic compound with the chemical formula CH2=CHC(O)NH2. It is a white odorless solid, soluble in water and several organic solvents. From the chemistry perspective, acrylamide is a vinyl-substituted primary ...

reacts with an aqueous solution of

formaldehyde Formaldehyde ( , ) (systematic name methanal) is an organic compound with the chemical formula and structure , more precisely . The compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde. It is stored as ...

in the presence of

copper(I) chloride Copper(I) chloride, commonly called cuprous chloride, is the lower chloride of copper, with the formula CuCl. The substance is a white solid sparingly soluble in water, but very soluble in concentrated hydrochloric acid. Impure samples appear gr ...

as a

polymerization inhibitor In polymer chemistry, polymerisation inhibitors (US: polymerization inhibitors) are chemical compounds added to monomers to prevent their self-polymerisation. Unsaturated monomers such as acrylates, vinyl chloride, butadiene and styrene require i ...

and

sulfuric acid Sulfuric acid (American spelling and the preferred IUPAC name) or sulphuric acid (English in the Commonwealth of Nations, Commonwealth spelling), known in antiquity as oil of vitriol, is a mineral acid composed of the elements sulfur, oxygen, ...

as catalyst to form ''N'',''N''′-methylenebisacrylamide with yields of 60 to 80%. MBA aus Acrylamid

The reaction proceeds via ''N''-hydroxymethylacrylamide, which can be detected in alkaline solution and decomposes in acid to give ''N'',''N''′-methylenebisacrylamide. Using acrylamide and

paraformaldehyde Paraformaldehyde (PFA) is the smallest polyoxymethylene, the polymerization product of formaldehyde with a typical degree of polymerization of 8–100 units. Paraformaldehyde commonly has a slight odor of formaldehyde due to decomposition. Par ...

in 1,2-dichloroethane gives a clear solution upon heating, from which MBA crystallizes. In aqueous media,

acrylonitrile Acrylonitrile is an organic compound with the formula and the structure . It is a colorless, volatile liquid. It has a pungent odor of garlic or onions. Its molecular structure consists of a vinyl group () linked to a nitrile (). It is an im ...

also reacts with formaldehyde to give crude ''N'',''N''′-methylenebisacrylamide, which can be purified by recrystallization with acetone/water.

Reactions and uses

Under basic conditions, MBA reacts further with formaldehyde at the amide nitrogen to give ''N''-hydroxymethyl,''N'',''N''′-methylenebisacrylamide. Nucleophiles such as

alcohol Alcohol may refer to: Common uses * Alcohol (chemistry), a class of compounds * Ethanol, one of several alcohols, commonly known as alcohol in everyday life ** Alcohol (drug), intoxicant found in alcoholic beverages ** Alcoholic beverage, an alco ...

amine In chemistry, amines (, ) are organic compounds that contain carbon-nitrogen bonds. Amines are formed when one or more hydrogen atoms in ammonia are replaced by alkyl or aryl groups. The nitrogen atom in an amine possesses a lone pair of elec ...

s, or

thiol In organic chemistry, a thiol (; ), or thiol derivative, is any organosulfur compound of the form , where R represents an alkyl or other organic substituent. The functional group itself is referred to as either a thiol group or a sulfhydryl grou ...

s add across the activated vinyl groups, giving mixtures of mono- and disubstituted products. : As a bifunctional electron-poor dienophile, MBA reacts with electron-rich dienes, such as

cyclopentadiene Cyclopentadiene is an organic compound with the chemical formula, formula C5H6. It is often abbreviated CpH because the cyclopentadienyl anion is abbreviated Cp−. This colorless liquid has a strong and unpleasant odor. At room temperature, ...

, in

Diels–Alder reaction In organic chemistry, the Diels–Alder reaction is a chemical reaction between a Conjugated system, conjugated diene and a substituted alkene, commonly termed the Diels–Alder reaction#The dienophile, dienophile, to form a substituted cyclohexe ...

s, giving the corresponding

norbornene Norbornene or norbornylene or norcamphene is a highly strained bridged cyclic hydrocarbon. It is a white solid with a pungent sour odor. The molecule consists of a cyclohexene ring with a methylene bridge between carbons 1 and 4. The molecule carr ...

adducts. : As a symmetric, unconjugated divinyl monomer, MBA can be used with suitable initiators in cyclopolymerizations to create linear, soluble polymers whose backbones are built from five- and seven-membered rings. With acrylic and vinylic monomers such as acrylonitrile, acrylamide, and substituted acrylamides, MBA can undergo radical

copolymerization In polymer chemistry, a copolymer is a polymer derived from more than one species of monomer. The polymerization of monomers into copolymers is called copolymerization. Copolymers obtained from the copolymerization of two monomer species are som ...

to form highly crosslinked gels, using peroxides, UV light, or redox initiators. : The properties of such gels are determined by the crosslink density, and targeted gel formation using MBA crosslinking gives useful technical properties used in various applications, such as in

adhesives Adhesive, also known as glue, cement, mucilage, or paste, is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation. The use of adhesives offers certain advantage ...

, paints, and superabsorbents. In biochemistry, MBA is used for chromatography gels and

polyacrylamide gel electrophoresis Polyacrylamide gel electrophoresis (PAGE) is a technique widely used in biochemistry, forensic chemistry, genetics, molecular biology and biotechnology to separate biological macromolecules, usually proteins or nucleic acids, according to their ...

References

Acrylamides Monomers {{Alkene-stub

Synthesis

Reactions and uses

See also

References