Hexahydro-1,3,5-trimethyl-1,3,5-triazine

Water solubility

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

Not reported

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

significant methodological deficiencies

Principles of method if other than guideline:

The hexahydro-1,3,5-trimethyl-s-triazine condensate reacts with HCl in the presence of water to form 3 moles of monomethylamine hydrochloride salt and 3 moles of formaldehyde. The hydrochloride salt of the amine may then be titrated with aqueous base and the hexahydro-1,3,5-trimethyl-s-triazine content calculated. In addition, the quantity of residual monomethylamine in the product is determined by a separate method (N2208) and the results for hexahydro-1,3,5-trimethyl-s-triazine corrected accordingly.

GLP compliance:

no

Type of method:

other: Method description provided below.

Key result

Water solubility:

> 340 g/L

pH:

>= 9.63 - <= 10.1

Remarks on result:

other: No temperature was defined in this assessment.

Measurements from 5 different batches are given.

Batch number	Methylamine % in R-3853	Hexahydro-1,3,5-trimethyl-s-triazine % in R-3853	pH (not a product specification)
FA8K0076	0.124	34.26	9.84
FA8K0093	0.145	33.81	10.1
FA8M0071	0.239	34.03	9.63
FA9A0165	0.246	33.2	9.84
FA9B0070	0.245	33.89	9.65

Conclusions:

Interpretation of results: very soluble (> 10000 mg/L) Minimum solubility based on presented data

Executive summary:

Hexahydro-1,3,5 -trimethyl-1,3,5 -triazine is typically produced by the reaction of a formaldehyde aqueous solution and anhydrous monomethylamine. Analytical data are available to demonstrate that this production process generates a solution with a measured aqueous concentration of 332 to 343 g/L at a pH of ca 10.

Reference 2

Endpoint:

water solubility

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Remarks:

The fragments of this chemical substance were within the domain of applicability for use with the EpiSuite WSKow module. Similar molecules were used in the training set and the validation set. The accuracy of the WSKow model was increase by the use of a laboratoey derivced octanol:water partition coefficient and pH (log Pow = 0.76; pH = 8).

Guideline:

other:

Version / remarks:

ECHA Guidance on Information Requirements and Chemical Safety Assessment, Chapter R.6: QSARs and Grouping of Chemicals. May 2008.

Principles of method if other than guideline:

(Q)SAR WSKOWWIN

Specific details on test material used for the study:

Smiles: C1N(C)CN(C)CN1C

Key result

Water solubility:

320 g/L

Temp.:

25 °C

Remarks on result:

other: QSAR predicted value

Key structural input parameters with water solubility output of the substance:

CAS number: 108-74-7

EC number: 203-612-8

Chemical name: CAS - 1,3,5-triazine, hexahydro-1,3,5-trimethyl; IUPAC - 1,3,5-trimethyl-1,3,5-triazinane

Structural formula: C6H15N3

Structure codes:

a. SMILES: C1N(C)CN(C)CN1C

b. InChI: Not applicable

c. Other structural representation: Not applicable

d. Stereochemical features: Not applicable

Predicted value (model result): 320 g/L

Predicted value (comments): 25 °C

Conclusions:

The water solubility of the substance was determined using the (Q)SAR WSKOWWIN to be 320 g/L (25 °C).

Reference 3

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

Not reported

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

This study was not intended to quantify the aqueous solubility of hexahydro-1,3,5-trimethyl-1,3,5-triazine, but determine the miscibility of the substance based on observation. The study was not conducted in accordance with any international guidelines.

Principles of method if other than guideline:

1,3,5 -trimethylhexahydro-1,3,5 -triazine 97 % (Sample reference: JM08 -10/07/09) was added to de-ionised water at ambient temperature (20 degrees celsius) in the weight ratios 1:99, 1:1 and 99:1 respectively. Miscibility was assessed by visual observation.

GLP compliance:

no

Type of method:

other: Visual miscibility assessment

Remarks on result:

other: Miscibility assessment in support of solubility endpoint, no "aqueous solubility" data generated in this assessment.

Results

Sample Identification	Weight Ratio of 1,3,5-Trimethylhexahydro-1,3,5-triazine : De-ionised Water	Weight / g		Result
		Trimethylhexahydro-1,3,5-triazine 97%	De-ionised Water
JM17/07/09_1	1:99	3.04	300.96	Stable homogenous solution.
JM17/07/09_2	1:1	37.86	37.86
JM17/07/09_3	99:1	130.68	1.32

 

Conclusions:

Interpretation of results: miscible1,3,5-trimethylhexahydro-1,3,5-triazine 97 % is completely miscible with water at all concentrations at ambient temperature.

Description of key information

Water Solubility = >340 g/L (pH 9.63 - 10.1) (Anon. 2010)

Water Solubility = 320 g/L (25 °C, pH = 8) (Hargreaves, 2010)

Water Solubility = Miscible (Mountford, 2010)

Key value for chemical safety assessment

Water solubility:

350 g/L

at the temperature of:

25 °C

Additional information

In practical terms, hexahydro-1,3,5-trimethyl-1,3,5-triazine can be described as being freely miscible with water. The minimum solubility is estimated to be 320 - 350 g/L at a pH of 10 and a temperature of 25 °C . At pH 10, ca 75 % will be non-ionised (refer to dissociation constant), as pH drops the ionisation will increase, which is associated with increased solubility (i.e. solubility will increase with decreasing pH).