Reaction products of [3-(2,3-epoxypropoxy)propyl]trimethoxysilane and triacetoxyvinylsilane.

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2016-01-20 to 2016-01-22

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Deviations:

no

GLP compliance:

yes

Type of method:

static method

Key result

Test no.:

#1

Temp.:

20 °C

Vapour pressure:

455 Pa

Key result

Test no.:

#1

Temp.:

25 °C

Vapour pressure:

559 Pa

The results of the static vapour pressure experiment are presented in Table 1 and Table 2 below, the summarised results are in Table 3.

Table 1: Determination of the vapour pressure of the test substance during the static vapour pressure experiment - Replicate 1

Test Temperature (°C)	Test Temperature (K)	Test temperature (1/K)	Vapour pressure (Pa)	ln Vapour pressure (Pa)
-10.2	262.95 262.95 262.95	0.00380 0.00380 0.00380	98.3 99.3 100	4.59 4.60 4.61
		Mean (Standard deviation)	99.2 (0.854)	4.60 (0.00862)
-5.1	268.05 268.05 268.05	0.00373 0.00373 0.00373	145 148 153	4.98 5.00 5.03
		Mean (Standard deviation)	149 (4.04)	5.00 (0.0271)
0.40	273.55 273.55 273.55	0.00366 0.00366 0.00366	190 193 197	5.25 5.26 5.28
		Mean (Standard deviation)	193 (3.51)	5.23 (0.0181)
6.8	279.95 279.95 279.95	0.00357 0.00357 0.00357	235 238 241	5.46 5.47 5.47
		Mean (Standard deviation)	238 (3.00)	5.47 (0.0126)
12.1	285.25 285.25 285.25	0.00351 0.00351 0.00351	313 316 319	5.75 5.76 5.77
		Mean (Standard deviation)	316 (3.00)	5.76 (0.00949)
-9.0	264.15 264.15 264.15	0.00379 0.00379 0.00379	127 128 129	4.84 4.85 4.86
		Mean (Standard deviation)	128 (1.00)	4.85 (0.00781)

Table 2: Determination of the vapour pressure of the test substance during the static vapour pressure experiment - Replicate 2

Test Temperature (°C)	Test Temperature (K)	Test temperature (1/K)	Vapour pressure (Pa)	ln Vapour pressure (Pa)
9.8	282.95 282.95 282.95	0.00353 0.00353 0.00353	279 286 288	5.63 5.66 5.66
		Mean (Standard deviation)	284 (4.73)	5.65 (0.0167)
15.0	288.15 288.15 288.15	0.00347 0.00347 0.00347	362 362 362	5.89 5.89 5.89
		Mean (Standard deviation)	362 (0.00)	5.89 (0.00)
20.0	293.15 293.15 293.15	0.00341 0.00341 0.00341	458 461 461	6.13 6.13 6.13
		Mean (Standard deviation)	460 (1.73)	6.13 (0.00377)
25.3	298.45 298.45 298.45	0.00335 0.00335 0.00335	559 557 559	6.33 6.32 6.33
		Mean (Standard deviation)	558 (1.15)	6.32 (0.00207)
30.1	303.25 303.25 303.25	0.00330 0.00330 0.00330	678 682 683	6.52 6.53 6.53
		Mean (Standard deviation)	681 (2.65)	6.52 (0.00389)
9.8	282.95 282.95 282.95 282.95	0.00353 0.00353 0.00353 0.00353	339 316 317 317	5.83 5.76 5.76 5.76
		Mean (Standard deviation)	322 (11.2)	5.77 (0.0341)

Note: Numbers may vary slightly due to rounding. Table includes all values to show stability over all measurements.

Table 3: Summary of results

Replicate	Test Temperature (°C)	Test Temperature (K)	Test temperature (1/K)	Vapour pressure (Pa)	ln Vapour pressure (Pa)
1	-10.2	262.95	3.80E-03	99.2	4.60E+00
1	-5.1	268.05	3.73E-03	149	5.00E+00
1	0.40	273.55	3.66E-03	193	5.26E+00
1	6.8	279.55	3.57E-03	238	5.47E+00
1	12.1	285.25	3.51E-03	316	5.76E+00
1	-9.0	264.15	3.79E-03	128	4.85E+00
2	9.8	282.95	3.53E-03	284	5.65E+00
2	15.0	288.15	3.47E-03	362	5.89E+00
2	20.0	293.15	3.41E-03	460	6.13E+00
2	25.3	298.45	3.35E-03	558	6.32E+00
2	30.1	303.25	3.30E-03	681	6.52E+00
2	9.8	282.95	3.53E-03	322	5.77E+00

When the data from both experiments are plotted together using the Clausious Clapeyon equation and linear regression is performed; the vapour pressure is extrapolated to be 455 Pa at 20°C and 559 Pa at 25°C. These estimates are confirmed by the observations of vapour pressure values of 460 Pa at 20°C and 558 Pa at 25.3°C during the definitive experiments.

Conclusions:

Vapour pressure values of 455 Pa at 20°C and 559 Pa at 25°C were obtained for the substance using a relevant test method and in compliance with GLP. The result is considered to be reliable.

Description of key information

Vapour Pressure [ Reaction mass of 3-(2,3-epoxypropoxy)propyltrimethoxysilane and triacetoxyvinylsilane]: 455 Pa at 20°C (OECD 104) 

Vapour Pressure [3-(2,3-epoxypropoxy)propyl]silanetriol]: 1.7E-05 Pa at 25°C (QSAR)

Vapour Pressure [Vinylsilanetriol]: 1.7E-02 Pa at 25°C (QSAR)

Vapour Pressure [acetic acid]: 2090 Pa at 25°C

Vapour Pressure [methanol]: 12790 Pa at 20°C

Key value for chemical safety assessment

Vapour pressure:

455 Pa

at the temperature of:

20 °C

Additional information

Vapour pressure values of 455 Pa at 20°C and 559 Pa at 25°C were determined for the substance using a static method in accordance with OECD Test Guideline 104 and in compliance with GLP. The result is considered to be reliable.

In contact with water, the substance hydrolyses rapidly (all constituents have predicted half-lives of <12 hours at 20- 25°C and pH 4, pH 7 and pH 9) to form 3-(2,3-epoxypropoxy)propyl]silanetriol, vinylsilanetriol, acetic acid and methanol. The vapour pressure of the silanol hydrolysis products, 3-(2,3-epoxypropoxy)propyl]silanetriol and vinylsilanetriol have been predicted to be 1.7E-05 Pa and 1.7E-02 at 25°C respectively using a validated QSAR estimation method.

A vapour pressure of 2090 Pa at 25°C was reported for acetic acid (Daubert and Danner 1985).

Methanol has a reported vapour pressure of 12790 Pa at 20°C (OECD 2004).

References:

Daubert and Danner (1985). Data compilation tables of properties of pure compounds. American Institute of Chemical Engineers. pp.450, 1985.

OECD 2004. SIDS Initial Assessment Report for SIAM 19, Berlin, Germany, 18-20 October 2004, Methanol, CAS 67-56-1