1,1-Difluoroethylene

Highly flammable, colorless gas with a faint ethereal odor

Gaseous

  • 2.89 kg · m-3 at 0 ° C and 1013 mbar
  • 1.12 g · cm -3 (liquid at boiling point )

-144 ° C

-84 ° C

3.612 MPa (20 ° C)

Moderately in water ( 254 g · l-1 at 25 ° C)

Risk

-335.0 KJ / mol

Template: Infobox chemical / molecular formula search available

1,1- difluoroethene is a chemical compound selected from the group consisting of aliphatic unsaturated fluorocarbons.

Production and representation

There are various production processes for 1,1- difluoroethene, such as dechlorination of 1,2- dichloro-1 ,1-difluoroethane or 1,1,1 - trifluoroethane Dehydrofluorination. The worldwide production volume in 1999 was about 33,000 tons.

Properties

1.1 difluoroethene is highly flammable, colorless gas with a faint ethereal odor. It is readily polymerizable and comes in compressed gas cylinders in liquid form in the trade. At higher temperature, it is chemically unstable. The critical temperature is 30.1 ° C, the critical pressure at 44.33 bar, the critical density of 6.51 mol.l -1 and the triple point temperature at -144 ° C ( melting temperature).

Use

1,1- difluoroethene is used to produce polyvinylidene fluoride ( CAS: 24937-79-9 ) and copolymer of chlorotrifluoroethylene and hexafluoropropylene ( TFB ) was used.

Safety

1.1 difluoroethene forms an explosive mixture with air. The explosion range is between 4.7 vol% (125 g/m3) as the lower explosive limit ( LEL) and 25.1 % by volume (664 g/m3 ) and upper explosive limit (UEL ). The ignition temperature is 390 ° C. The fabric falls within the temperature class T2. During thermal decomposition of hydrogen fluoride forms.

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