Registration Dossier

Administrative data

vapour pressure
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Reliability rating was 1 because study followed EU Method A.4 and was carried out under GLP. The study was well-documented.

Data source

Reference Type:
study report
Report date:

Materials and methods

Test guideline
according to guideline
EU Method A.4 (Vapour Pressure)
GLP compliance:
Type of method:
effusion method: vapour pressure balance

Test material

Constituent 1
Reference substance name:
MCP 968
MCP 968
Constituent 2
Chemical structure
Reference substance name:
A mixture of isomers of: mono-(2-tetradecyl)naphthalenes; di-(2-tetradecyl)naphthalenes; tri-(2-tetradecyl)naphthalenes
EC Number:
EC Name:
A mixture of isomers of: mono-(2-tetradecyl)naphthalenes; di-(2-tetradecyl)naphthalenes; tri-(2-tetradecyl)naphthalenes
Cas Number:
Molecular formula:
Can vary from C24H36 (mono rxn product) to C52H92 (tri rxn product)
2,3,6-tritetradecylnaphthalene; 2,3-ditetradecylnaphthalene; 2-tetradecylnaphthalene

Results and discussion

Vapour pressure
25 °C
Vapour pressure:
< 0 Pa
Remarks on result:
other: The test substance was determined to have a vapour pressure of 0.00034 Pa at 25 C

Any other information on results incl. tables

Vapor pressure (Vp) is related to temperature through the equation:

log10 Vp (in Pascal) = [ Slope /temp (in degree Kelvin)] + intercept.

A plot of log 10 Vp (in Pascal) versus reciprocal temperature in Kelvin gives a straight line graph.


The vapor pressure of the test material was measured over a range of temperatures to enable extrapolation of the vapor pressure at 25C or 298 K. Using this relationship and the vapor pressure - temp graphs, back extrapolation to 298 K provided a vapor pressure determination of less than 3.4 x10-4 Pascal at 25 C for the test material.

Vapour pressure was determined using a vapor pressure balance (CI Electronics microbalance) with a sensitivity of approximately 0.1 microgram. The temp of the sample was controlled electronically. The mass and temp readings were recorded directly onto a 2 channel chart recorder. On opening the slide across the orifice in the temp-controlled evaporation furnance, the escaping vapor jet was directed at the scale pan. The vapour pressure was determined directly from the pressure on the pan by measuring the difference of mass readings when the slide across the orifice was open and closed and also when sufficient condensation occurs from the rate of the latter onto the pan. The vapour pressure of the sample was measured at several temperatures to yield vapor pressure curves for subsequent extrapolation to give a Vp value at 298 K

Applicant's summary and conclusion

The EU Method A4 of the Directive 92/69/EEC was used to determine vapor pressure. The test substance was found to have a vapor pressure of less than 0.00034 Pa at 25 degrees Centigrade.
Executive summary:

The test substance was found to have a vapor pressure of < 0.00034 Pa at 25 C