N , N '-methylene bisacrylamide

Structural formula
General
Surname	N , N '-methylene bisacrylamide
other names	N , N ′ -Methylene bis (acrylamide) N , N ′ -methylene bis (2-propenamide) N , N ′ -methylene diacrylamide Bis [acryloylamino] methane MBA
Molecular formula	C 7 H 10 N 2 O 2
Brief description	white to almost white crystalline solid
External identifiers / databases
CAS number 110-26-9 EC number 203-750-9 ECHA InfoCard 100.003.411 PubChem 8041 Wikidata Q3869308
properties
Molar mass	154.17 g mol −1
Physical state	firmly
density	1.235 g cm −3 (30 ° C)
Melting point	185 ° C (decomposition) 300 ° C
solubility	soluble in water (30 g / l at 25 ° C) soluble in methanol (82 g / l at 30 ° C) soluble in DMF (12.5 g / 100 ml at 23 ° C), in DMF / 1.0 N NaOH 90/10 (> 100 g / 100 ml at 23 ° C), in NMP / 1.0 N NaOH 90 / 10 (75 g / 100 ml 23 ° C)
safety instructions
GHS labeling of hazardous substances Caution H and P phrases H: 302 P: 301 + 312 + 330
Toxicological data	390 mg kg −1 ( LD 50 ,  rat ,  oral )
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

N , N -methylenebisacrylamide (MBA) is a symmetrical, non-conjugated bifunctional vinyl - monomer , which as a crosslinking agent , in particular for polyacrylamide - gel is used.

Manufacturing

Acrylamide reacts in aqueous solution with formaldehyde solution in the presence of copper (I) chloride as a polymerization inhibitor and dilute sulfuric acid as a catalyst in yields of 60 to 80% to form N , N '-methylene bisacrylamide.

The reaction takes place via the N -hydroxymethylacrylamide, which can be detected in an alkaline medium, by elimination of water in acid to form N , N '-methylene bisacrylamide and, when acrylamide and paraformaldehyde are used in 1,2-dichloroethane, when heated in the presence of concentrated hydrochloric acid, gives a clear solution from which MBA then crystallized out.

In an aqueous acidic medium, acrylonitrile also reacts with formaldehyde solution to form crude N , N ′ -methylene bisacrylamide, from which the pure substance can be obtained by recrystallization from acetone / water.

properties

N , N ′ -Methylene bisacrylamide is a white and odorless crystalline solid that does not dissolve very much in cold water.

Solubilities in water
temperature	in ° C	10	25th	50	90
solubility	in g / 100 ml	2.0	3.0	6.5	42.0

If small amounts of caustic soda are added , however, the substance dissolves very well at room temperature in aprotic dipolar solvents such as dimethylformamide and N-methylpyrrolidone .

Solubilities in organic solvents
solvent	at 30 ° C	acetone	benzene	chloroform	Dioxane	Ethanol	Ethyl acetate	Methanol	n -heptane
solubility	in g / 100 ml	1.0	<1.0	0.3	1.1	5.4	0.4	8.2	<0.02

The decomposition of MBA at high temperatures produces water, carbon dioxide and nitrogen, but not acrylamide.

Applications

Under basic conditions, MBA reacts with formaldehyde on the amide nitrogen to form a mixture of MBA and the N-methylol compound N -hydroxymethyl, N , N '-methylene bisacrylamide.

Nucleophiles such as B. alcohols , amines or thiols are added to the activated vinyl groups of N , N '-Methylene bisacrylamide, mixtures of mono- and disubstitution products being formed.

As an electron-poor dienophile , the bifunctional MBA forms with electron-rich dienes such as B. cyclopentadiene in a Diels-Alder reaction of the corresponding bis norbornene - adduct .

The symmetrical non-conjugated divinyl monomer N , N '-methylene bisacrylamide can be converted with suitable initiators in a cyclopolymerization to linear, soluble polymers, the backbone of which should be composed of five- and seven-membered rings.

With acrylic and vinyl monomers such as acrylonitrile , acrylamide , substituted acrylamides, such as. B. N-isopropylacrylamide , acrylic acid and acrylates, and derivatives of these compounds (z. B. methacrylates ) can N , N '-Methylenbisacrylamid in solution, in emulsion or in suspension radically with peroxides, such as. B. benzoyl peroxide azo compounds e.g. B. AIBN or UV light or by redox initiation, e.g. B. be copolymerized with ammonium peroxodisulfate (APS) / tetramethylethylenediamine (TMEDA) to form highly crosslinked gels .

The properties of the gel crosslinked with MBA are determined by the molar mass of the underlying polymer, the polymer concentration and the MBA concentration, i. H. determined by the crosslink density. The targeted gel formation through crosslinking with N , N '-Methylene bisacrylamide gives (water) soluble polymers extremely useful technical properties that manifest themselves in a variety of applications, such as. B. in adhesives , thickeners, paints and coatings and superabsorbents .

Since methylenebisacrylamide contains two double bonds between carbon atoms, it is used as a crosslinker in the radical polymerization of aqueous acrylamide solutions . In biochemistry it is used for chromatography gels and polyacrylamide gel electrophoresis , e.g. B. in SDS-PAGE , in BAC-PAGE , in CTAB-PAGE and in DNA sequencing gels .

Individual evidence

1. ↑ ^{a b c} data sheet N, N′-methylene-bis-acrylamide from Sigma-Aldrich , accessed on November 30, 2015 ( PDF ).
2. ↑ ^{a b} Entry on N, N′-Methylenebisacrylamide (for Electrophoresis) at TCI Europe, accessed on November 30, 2015.
3. ↑ ^{a b c} Entry on N, N′-methylenebis (acrylamide) in the GESTIS substance database of the IFA , accessed on January 8, 2018(JavaScript required) .
4. ↑ Data sheet N, N′-methylenebisacrylamide for electrophoresis (PDF) from Merck , accessed on November 30, 2015.
5. ↑ ^{a b c d e f g} SNF Floerger : Flocryl® MBA product brochure , accessed on May 1, 2018.
6. ↑ ^{a b c} Patent US5354903 : Polymers prepared from concentrated solutions of N, N'-methylenebisacrylamides. Filed December 24, 1992 , published October 11, 1994 , Applicant: Ionics, Inc., Inventor: RJ MacDonald. ‌
7. ↑ Patent US2475846 : Alkylidene-bis-acrylamides. Filed October 31, 1946 , published July 12, 1949 , applicant: American Cyanamid, Co., inventor: LA Lundberg. ‌
8. ↑ H. Petersen, Amino-Harze in Houben-Weyl Methods of Organic Chemistry, Vol. E20, Thieme Stuttgart New York 1987, ISBN 978-3-13-219004-7 , p. 1855.
9. ↑ H. Feuer, UE Lynch: The synthesis and reactions of unsaturated N-methylolamides . In: J. Am. Chem. Soc. tape 75 , no. 20 , 1953, pp. 5027-5029 , doi : 10.1021 / ja01116a041 .
10. ^ EE Magat, BF Faris, JE Reith, LF Salisbury: Acid-catalyzed reactions of nitriles. I. The reaction of nitriles with formaldehyde . In: J. Am. Chem. Soc. tape 73 , no. 3 , 1951, pp. 1028-1031 , doi : 10.1021 / ja01147a042 .
11. ↑ A. Gopalan, S. Paul Rajan, NR Subbaratnam, K. Venkata Rao: Cyclopolymerization of N, N'-methylene bisacrylamide initiated by S2O82 - Fe2 + redox system . In: J. Polym. Chem. Band 38 , no. 10 , 2005, pp. 4465-4471 , doi : 10.1021 / ma0502497 .
12. ^ K. Behari, U. Agrawal, R. Das: Gel free polymerization of N, N'-methylenebisacrylamide initiated by a peroxodiphosphate-thioacetamide redox system. A kinetic study . In: Polym. J. Band 25 , no. 10 , 1993, p. 1007-1013 , doi : 10.1295 / polymj.25.1007 .
13. ↑ N. Krishnaveni, M. Umayavalli: Cyclopolymerization of N, N'-methylenebisacrylamide with N, N-dimethylaniline-trichloroacetic acid and N, N-dimethylaniline-benzoyl chloride systems in aqueous medium . In: J. Chem. Pharm. Res. Volume 6 , no. 9 , 2014, p. 349-359 ( jocpr.com [PDF]).
14. ↑ HH Prasad, A. Senger, K. Chauhan, KM Popat, PS Anand: Synthesis of crosslinked methacrylic acid-co-N, N'-methylene bis acrylamide sorbents for recovery of heavy metal ions from dilute solutions . In: Indian J. Chem. Technol. tape 8 , 2001, p. 371-377 ( 14.139.47.15 [PDF]).
15. ↑ A. Ekenseair, KWM Boere, SN Tzouanas, TN Vo, FK Kasper, AG Mikos: Synthesis and Characterization of Thermally and Chemically Gelling Injectable hydrogel for tissue engineering . In: Biomolecules . tape 13 , no. 6 , 2012, p. 1908-1915 , doi : 10.1021 / bm300429e .
16. ^ NF Ayub, S. Hashim, J. Jamaluddin, R. Rasit Ali, N. Adrus: UV LED Curing Formulation for Polyacrylamide Hydrogels . In: Adv. Mater. Res. Band 1125 , 2015, p. 84-88 , doi : 10.4028 / www.scientific.net / AMR.1125.84 .
17. ↑ A. Chetty, J. Kovács, Zs. Sulyok, Á. Mészáros, J. Fekete, A. Domján, A. Szilágyi, V. Vargha: A versatile characterization of poly (N-isopropylacrylamideco-N, N′-methylene-bis-acrylamide) hydrogels for composition, mechanical strength, and rheology . In: eXPRESS Polym. Lett. tape 7 , no. 1 , 2013, p. 95-105 , doi : 10.3144 / expresspolymlett.2013.9 .