Page 603 - Carrahers_Polymer_Chemistry,_Eighth_Edition

566 Carraher’s Polymer Chemistry

Vinyl acetate was produced by the catalytic acetylation of acetylene, but this monomer is now
produced by the catalytic oxidative condensation of acetic acid and ethylene (Equation 17.32). Other
vinyl esters can be produced by the transesterifi cation of vinyl acetate with higher boiling carbox-
ylic acids.

O
H C CH
H C CH 2 + H C 2 3
3
2
O (17.32)
OH
O
Ethylene Acetic acid Vinyl acetate

Acrylonitrile (vinyl cyanide) is produced by the Sohio process involving the ammoxidation of
propylene. Again, since this monomer is carcinogenic, care must be taken to minimize exposure
to it.

N
CH 3
HC + NH 3 + O 2 CH 2 + HO (17.33)
2
2
Propylene Ammonia Acrylonitrile

Tetrafluoroethylene is produced from the thermal dehydrochlorination of chlorodifl uoromethane

(Equation 17.35), which, in turn, is produced from chloroform and hydrogen fl ouride (HF)
(Equation 17.34).

Hydrogen Chloroform Hydrogen Chlorodifluoro-
fluoride chloride methane
H H
(17.34)
H F + H Cl +
Cl F
Cl Cl
Cl F
H F F

H Cl +
F F F (17.35)
Cl
F
Tetrafluoroethylene

Trifluoromonochloroethylene is obtained from the zinc metal dechlorination of trichlorotrifl uo-
roethane. The latter is produced by the fluorination of hexachloroethane.

Cl Cl Cl F
F F
Cl Cl F Cl
+ ZnCl 2
F Cl (17.36)
Cl Cl F Cl
Hexachloroethane Trichlorotrifluoro- Trifluoromonochloro
ethane ethylene

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