Colorless to yellowish liquid
1.04 g · cm -3 ( 20 ° C)
13 ° C
148 ° C ( 133 hPa)
13 hPa ( 91 ° C)
Miscible with water
1.512 at 20 ° C.
1022 mg · kg -1 ( LD50, rat, oral)
Template: Infobox chemical / molecular formula search available
N- vinyl-2 -pyrrolidone ( NVP) is a colorless liquid with a faint but characteristic odor. Is a heterocyclic organic compound is not one of the aromatics. In the chemical industry, it is used for the preparation of polymers, UV-curable coatings and inks.
Production and representation
In the first step of the synthesis γ -butyrolactone is reacted with ammonia. 2- pyrrolidone - - The product is in a vinylated Reppe synthesis with acetylene.
With rapid cooling to below a temperature of 13 ° C vinylpyrrolidone may have the behavior of a super-cooled liquid, which is rather uncommon for organic substances. In the presence of a seed crystal, it then comes to a rapid exothermic crystallization, which can be confused with a spontaneous polymerization.
- Flash point: 95 ° C
- Heat of fusion: 153 kJ / kg
- Viscosity: 2.4 MPa (20 ° C)
- Thermal conductivity: 0.157 W / m · K (20 ° C)
Vinyl pyrrolidone is soluble in many organic solvents, such as acetone, diethyl ether, ethanol, toluene and benzene. It is very reactive and tends to spontaneous polymerization. It must therefore be stabilized for longer- term storage. Usually this is done with potassium hydroxide or sodium hydroxide or an organic stabilizer, such as N, N' -di- sec-butyl -p-phenylenediamine. The polymerization is initiated by UV radiation. The heat of polymerization is -64.3 ± 1.9 kJ / mol.
Due to its UV - sensitivity is used for the production of UV-curing inks, paints and coatings, as well as a photoinitiator for other polymers. Furthermore, a variety of polymers prepared from vinyl pyrrolidone. The product range includes this linear polyvinylpyrrolidone ( PVP), crosslinked polyvinylpolypyrrolidone ( PVPP), as well as numerous copolymers.
Vinylpyrrolidone is classified as carcinogenic category 3, ie a carcinogenic effect in humans is suspected because an increased incidence of liver and laryngeal tumors was observed in animal studies in rats.
No special method is known, in order to detect NVP, usually, therefore, the gas chromatography is used.