N,N-dimethylaniline

Endpoint summary

Additional information

Appearance/physical state/color:

On basis of visual observation/ Olfactory property, the substance N,N-dimethylaniline was found to be a colourless organic liquid with an unpleasant odour at 35°C and 960 hPa

Melting point/freezing point:

N,N-dimethylaniline is a liquid and therefore the freezing point measurement is applicable for the same. Freezing point of N,N-dimethylaniline is found to be in the range of 1.5-2.5°C.

Boiling point:

The experimental value of the boiling point of N,N-dimethylaniline by the distillation method was estimated to be 185°C at 960 hPa. The chemical did not decompose at the experimental boiling point.

Density:

The experimental value of density of N,N-dimethylaniline calculated by the mass by volume method was estimated to be 0.926 g/cm³ at room temperature of 35°C. For the purpose of chemical safety assessment, the experimental value of 0.926 considered.

The supporting studies also show the density of N,N-dimethylaniline to be in the range of 0.955 g/cm³ to 0.96 g/cm³ at 20°C.

Particle size distribution (Granulometry):

Granulometry (particle size distribution is a property that is relevant only to solids. Since N,N-dimethylaniline is a liquid substance this testing was not scientifically possible and hence this end point was considered to be waived.

Vapour pressure:

The vapor pressure is the pressure at which a liquid is in equilibrium with its vapour. Vapour Pressure of N,N-dimethylaniline is estimated to be 60.7 Pa at 25°C using the Modified Grain method

Partition coefficient:

The experimental value of octanol water partition co-efficient (log Pow) of N,N-dimethylaniline is found to be 1.171 at 35°C and pH 6.58 by shake flask method. This value indicates that N,N-dimethylaniline is relatively hydrophillic in nature.

Water solubility:

The water solubility of N,N-dimethylaniline is found to be 1450 mg/L at 20°C. This value indicates that the substance is soluble in water.

Solubility in Organic solvents:

Gravimetric method was used to determine the solubility of the substance in organic solvent. The experimental value of solublility of N,N-dimethylaniline in methanol is found to be 1000000 mg/L at 35°C.

Using the Soxhlet/Solvent extraction method, solublility of N,N-dimethylaniline in petroleum ether is found to be 1000000 mg/L at 35°C.

Surface tension:

Surface tension is a property of the surface of a liquid that allows it to resist an external force. The surface tension of N,N-dimethylaniline was found to be 35.52 mN/m at 25°C.

Flash point:

The experimental value of flash point of N,N-dimethylaniline by the closed cup method was found to be 61°C at 960 hPa. This value indicates that N,N-dimethylaniline is non flammable by CLP criteria

Auto flammability:

The autoignition temperature or kindling point of a substance is the lowest temperature at which it will spontaneously ignite in a normal atmosphere without an external source of ignition, such as a flame or spark. The auto ignition temperature of N,N-dimethylaniline was determined in the laboratory but it was found that this chemical do not catch fire at room temperature of 35°C and atmospheric pressure of 960 hPa. Thus it can be concluded that that N,N-dimethylaniline is not auto flammable.

Flammability:

N, N-dimethylaniline ignited only when the flame of bunsen burner having temperature of 950°C is brought in contact with it. Thus it can be concluded that N, N-dimethylaniline is flammable only at high temperature of about 950°C. However since such high temperatures are not found under normal circumstances of transportation and use, N, N-dimethylaniline is considered as non-flammable for chemical safety assessment

Explosiveness:

In accordance with column 2 of Annex VII, this testing was considered for waiver since there are no chemical groups associated with explosive properties in N,N-dimethylaniline.

Oxidising properties:

N, N-dimethylaniline is experimentally found to exhibit oxidizing property since an end point of 71.3 ml of KMnO4 was obtained per 100 g of analyte N, N-dimethylaniline. However, it is not a strong oxidising agent and was therefore not considered as an oxidant for classification.

Stability in organic solvents and identity of relevant degradation products:

N,N-dimethylaniline was found to be stable in organic solvent dichloro methane and no degradation products were formed after 24 hours as evident from the comparitive GC-MS chromatogram obtained at 0 hours and that obtained after 24 hours.

pH:

1% by volume solution of N,N-dimethylaniline was found to exhibit a pH of 6.46 at 29°C. Thus 1% by volume solution of N,N-dimethylaniline is weakly acidic in nature.

Dissociation constant:

The average experimental pKa value for N,N-dimethylaniline is found to be 0.00000000000142 at 30 °C indicating that it has very low dissociating properties. This value when converted at 20°C pKa found to be pKa = 0.0000000000009466667.

The other authoritative supporting source indicates the pka valuedifferent from the key study which could be due to the difference in the estimation conditions. However for the chemical safety report, the key studyshall be considered.

Viscosity:

The dynamic viscosity of N,N-dimethylaniline was found to be 11.00088 mPa.s at 35°C. This is equivalent to 19.2515 mPa.s at 20°C.

The kinematic (static) viscosity of N,N-dimethylaniline was found to be 11.88 centistokes (mm²/s (static) at 35°C