Alkenes, C15-18-branched and linear, maleated, hydrolyzed

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2010

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Principles of method if other than guideline:

The sample was prepared in triplicate in solid saturator columns between glass wool plugs. The columns were placed into the custom built thermostated incubator (set at 25°C) and attached to the Nitrogen gas line. One end of each of the columns ¿poked¿ out of the side of the incubator, where an adequately sized vessel was securely attached to act as a trap for the analyte. The analyte was trapped in 2-Propanol. The gas flow rate was directly measured (in triplicate) periodically throughout the analysis.

After a finite length of time, all the traps were quantitatively transferred to individual 100ml volumetric flasks. All solutions were filled to the mark with 2-Propanol when equilibrated to RT. All solutions (the solutions were called VP 1, VP 2 and VP 3 respectively) were analysed by GC-FID to quantitate any analyte present

GLP compliance:

yes

Type of method:

gas saturation method

Key result

Temp.:

20 °C

Vapour pressure:

< 0.002 Pa

The above data doesn't prove, definitively, that gas saturation had occurred (as no analyte was detected and as a consequence all subsequent calculations were carried out using a ¿less than figure¿ than the LOQ) and therefore it has been assumed. For gas saturation to be achieved, the extreme gas flow rates (VP 1 versus VP 3) have to be >30% different (which they were for this analysis, 96.7% difference in extreme gas flow rate) and the calculated vapour pressure be <30% different.

 

As a result, the worst case scenario has been quoted as the result (VP1 data), purely as it gave the largest, calculated vapour pressure data (due to it having the slowest gas flow rate).

 

In conclusion, on the assumption that these gas flow rates would have achieved gas saturation of the analyte and that the analyte was stable in solution for the duration of the analysis, ASG:10423936 vapour pressure at 24.4°C for the customer specified analyte = <2.5x10^-3Pa (and inferred at 20°C = <2.5x10^-3Pa ).

Conclusions:

Vapour pressure at 24.4°C for the specified analyte = <2.5x10-3Pa (and inferred at 20°C = <2.5x10-3Pa ).

Executive summary:

The above data doesn't prove, definitively, that gas saturation had occurred (as no analyte was detected and as a consequence all subsequent calculations were carried out using a ¿less than figure¿ than the LOQ) and therefore it has been assumed. For gas saturation to be achieved, the extreme gas flow rates (VP 1 versus VP 3) have to be >30% different (which they were for this analysis, 96.7% difference in extreme gas flow rate) and the calculated vapour pressure be <30% different.

 

As a result, the worst case scenario has been quoted as the result (VP1 data), purely as it gave the largest, calculated vapour pressure data (due to it having the slowest gas flow rate).

 

In conclusion, on the assumption that these gas flow rates would have achieved gas saturation of the analyte and that the analyte was stable in solution for the duration of the analysis, ASG:10423936 vapour pressure at 24.4°C for the specified analyte = <2.5x10^-3Pa (and inferred at 20°C = <2.5x10^-3Pa ).

Description of key information

The vapour pressure of the test material was determined according to test guideline EU A4

Key value for chemical safety assessment

Vapour pressure:

0.003 Pa

at the temperature of:

20 °C