Reaction mass of α-3,3-trimethyl-(αS,1R)-cyclohexanemethanol and α-3,3-trimethyl-(αR,1S)-cyclohexanemethanol

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

29 September 2017 - 05 October 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Study conducted according to OECD 104 and EU A.4 guidelines, under GLP without deviation and with certificate of analysis included.

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

2017-01-10

Type of method:

dynamic method

Test no.:

#1

Temp.:

293.15 K

Vapour pressure:

ca. 8.4 Pa

Remarks on result:

other: First trial

Test no.:

#1

Temp.:

298.15 K

Vapour pressure:

ca. 15.3 Pa

Remarks on result:

other: First trial

Test no.:

#2

Temp.:

293.15 K

Vapour pressure:

ca. 8.5 Pa

Remarks on result:

other: Second trial

Test no.:

#2

Temp.:

298.15 K

Vapour pressure:

ca. 16.3 Pa

Remarks on result:

other: Second trial

Key result

Temp.:

293.15 K

Vapour pressure:

ca. 8.5 Pa

Remarks on result:

other: Mean

Key result

Temp.:

298.15 K

Vapour pressure:

ca. 15.8 Pa

Remarks on result:

other: Mean

First trial:

Mass loss (mg)	Mass loss duration (s)	Vapour pressure (Pa)	Temperature (K)	1/T (K^-1)	Log10(p)
0.988	600	11.9090	296.05	3.371E-03	1.0759
1.392	600	16.8662	299.15	3.347E-03	1.2270
3.272	600	40.1130	306.25	3.323E-03	1.6033
7.522	600	93.3530	313.85	3.299E-03	1.9701
16.03	600	201.3999	321.65	3.273858E-03	2.3041

A plot of Log₁₀(p) versus reciprocal temperature (1/T) (with p in Pa and T in K) gives the following statistical data using an unweighted least square treatment.

Slope              -4608.8 

Intercept          16.643 

R²                   0.9996

 

The results obtained indicate the following vapour pressure relationship: 

Log₁₀(p (Pa)) = -4608.8 / T (K) + 16.643

 

The above equation yields a vapour pressure of 8.4 Pa at 293.15 K and 15.3 Pa at 298.15 K.

Second trial:

Mass loss (mg)	Mass loss duration (s)	Vapour pressure (Pa)	Temperature (K)	1/T (K^-1)	Log10(p)
1.017	600	12.2626	296.25	3.376E-03	1.0886
1.451	600	17.5723	298.85	3.346E-03	1.2448
3.481	600	42.6125	305.35	3.275E-03	1.6295
8.035	600	99.4970	312.45	3.201E-03	1.9978
16.935	600	212.2736	320.15	3.124E-03	2.3269

A plot of Log₁₀(p) versus reciprocal temperature (1/T) (with p in Pa and T in K) gives the following statistical data using an unweighted least square treatment.

Slope              -4952.3

Intercept          17.823 

R²                   0.9978

 

The results obtained indicate the following vapour pressure relationship:

Log₁₀(p (Pa)) = -4952.3/ T (K) + 17.823

 

The above equation yields a vapour pressure of 8.5 Pa at 293.15 K and 16.3 Pa at 298.15 K.

Conclusions:

The vapour pressure of α-3,3-TRIMETHYLCYCLOHEXANEMETHANOL MULTICONSTITUEN is 8.5 Pa at 20°C and 15.8 Pa at 25°C.

Executive summary:

A study was performed to determine the vapour pressure of the test item α-3,3-TRIMETHYLCYCLOHEXANEMETHANOL MULTICONSTITUENT. The method followed was designed to be compliant with the OECD Guideline for Testing of Chemicals No. 104, ''Vapour Pressure'', adopted in March 2006 and Regulation (EC) No 761/2009, EC A4, 23 July 2009.

In this dynamic method, the mass of the test substance flowing out per unit of time of a Knudsen cell in form of vapour, through a micro-orifice under ultra-vacuum conditions was determined at various specified temperatures (from 22.9 to 48.5 °C). The Hertz-Knudsen equation was used to calculate the vapour pressure corresponding to the mass loss rate.

The log₁₀ (Vapour Pressure (Pa)) was plotted against 1/T (K) and a linear function was obtained. With this equation, the vapour pressure has been calculated for temperatures at 20°C and 25°C.

Two trials were conducted and five points were recorded foreach trial. Log₁₀ (Vapour Pressure (Pa)) was plotted against reciprocal temperature and values of vapour pressure were calculated at 20°C and 25°C with the linear function parameters (slope and intercept):

Trial  Vapour pressure at 293.15 K  Vapour pressure at 298.15 K  1  8.4 Pa  15.3 Pa  2  8.5 Pa  16.3 Pa  Mean  8.5 Pa 15.8 Pa

Calculated values respect validity criteria (less than 20% of difference) and the linear functions obtained own a correlation coefficient R² over 0.95.

Moreover the calculated values showed good correspondence with the experimentally determined ones.

In conclusion, the vapour pressure of α-3,3-TRIMETHYLCYCLOHEXANEMETHANOL MULTICONSTITUENT is 8.5 Pa at 20°C and 15.8 Pa at 25°C.

Description of key information

Vapour pressure of α-3,3-TRIMETHYLCYCLOHEXANEMETHANOL MULTICONSTITUENT:
8.5 Pa at 20°C

15.8 Pa at 25°C

Key value for chemical safety assessment

Vapour pressure:

8.5 Pa

at the temperature of:

20 °C

Additional information

A study was conducted according to OECD 104 and EU A.4 guidelines to measure vapour pressure of α-3,3-TRIMETHYLCYCLOHEXANEMETHANOL MULTICONSTITUENT. As the results were obtained under GLP without deviation, they were considered as valid and reliable without restriction and used to propose a key value.