Dichloroethylene, physical properties

Dichloroethylene consists of a mixture of the cis and trans isomers, as manufactured. The physical properties of both isomeric forms are Hsted ia Table 1. Biaary and ternary a2eotrope data for the cis and trans isomers are given ia Table 2. 

Table 1. Physical Properties of the Isomeric Forms of 1,2-Dichloroethylene...

The CPVC obtained by the various processes (9, 10, 20, 22) differs in many chemical physical properties. According to the most recent studies carried out with infrared (5, 8, 22) and NMR techniques (13,18, 19), these differences are not justified by the determination of the structure, in terms of the ratio between 1.2 and 1.1 dichloroethylene units. 

Property data from the literature (1-55,88,89,100,105,107,111,113,114,117,125,139,261-263) are given in Table 18-1. The critical constants are from the DIPPR project (5) except for cis- and trans-dichloroethylene (44,47). Additional property data such as acentric factor, enthalpy of formation, lower explosion limit in air and solubility in water are also available. The DIPPR (Design Institute for Physical Property Research) project (5) and recent data compilations by Yaws and co-workers (44-55) were consulted extensively in preparing the tabulation. 

PHYSICAL PROPERTIES colorless to yellow liquid or pale yellow crystals viscous liquid sweet burning taste miscible with ether, acetone, glacial acetic acid, ethyl acetate, pyridine, chloroform, ethylene bromide, benzene, nitrobenzene, and dichloroethylene sparingly soluble in petroleum ether, glycerol and liquid petrolatum practically insoluble in water MP... 

Because a double bond between two carbons prevents the carbons from rotating, isomers involving the atoms bonded to the carbons are possible, as shown above with dichloroethylene. Such isomers are called geometrical isomers, in contrast to the structural isomers discussed previously. When the substiuent groups are on the same side of the molecule, the compound is designated the cis- isomer. When the substituent groups are on the opposite side, the compound is the trans- isomer. Like all isomers, cis- and trans-isomers have the same molecular formula, but differ in certain physical and chemical properties. For example, cw-l,2-dichloroethylene boils at 60°C whereas 1,2-dichloroethylene boils at 48°C. 

Vinylidene Chloride, Inhibited — (i) Chemical Designations — Synonyms 1,1-Dichloroethylene, unsym-Dichloroethylene Chemical Formula CH2=CClj (ii) Observable Characteristics — Physical State (as normally. shipped) Liquid Color Colorless Odor Sweet, like carbon tetrachloride or chloroform (iii) Physical and Chemical Properties — Physical State at 15 °C and I atm. Liquid Molecular Weight 96.95 Boiling Point at I atm. 88.9, 31.6, 304.8 Freezing Point -... 

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