Registration Dossier

Physical & Chemical properties

Endpoint summary

Administrative data

Description of key information

Physico-chemical properties were available from literature, or determined from experimental testing. Some endpoints were waived, based on chemical structure.

The substance is a dense solid at ambient temperature, with low volatility. It turns to a wet paste when exposed to air, due to degradation.

In water, it is very soluble, with no surface-active properties. It will ionise in basic media, therefore solubility and partitioning are anticipated to undergo pH-dependency.

It has low potential for bioaccumulation and aquatic chronic toxicity.

It decomposes upon heating, but is NOT classified as dangerous with regard to physical hazards, based on CLP criteria. However, dust explosion potential should be considered, due to small particle size.

Additional information

Summary of relevant physico-chemical properties:

Endpoint

Data

Appearance

(visual)

White to pale yellow powder.

Melting point

(literature)

ca 79°C

Boiling point

(OECD 103/EU A2, dynamic)

decomposes from ca 200°C before boiling at ca 230°C

Relative density

(OECD 109/EU A3, pycnometer with replacement liquid)

1.3217

Vapour pressure

(OECD 104/EU A4/effusion Knudsen)

0.81 Pa at 25°C (close extrapolation)

Partition coefficient

(literature, flask-like method)

Log Kow = 0.95 (at pH 2.5, non-ionised form)

LogD = - 0.133 in pure water (pH not specified)

Water solubility

(OECD 105/EU A6, flask method)

176 g/L (20°C, pH ca 2)

Surface tension

(OECD 115/EU A5/plate)

71.78 mN/m, at 1 g/L

Flammability

(UN N1, preliminary test)

No ignition in contact with a flame. (melts only)

Self-Ignition Temperature, Self-heating properties

(data waiving)

No relative self-ignition, or self-heating, anticipated, as a low melting solid.

Flammability if contact with air or water

(data waiving)

No pyrophoric properties expected, or release of flammable gas, based on chemical structure and experience.

 Explosive properties 

 (UN MTC App.6/DSC screening test and Test series 1)

 No structural alert, but maximum decomposition energy = -950 J/g in the temperature range of 220-400°C.

Koenen tube, time/pressure and Trauzl tests negative.

 Oxidising properties 

 (data waiving)

 No oxidising properties anticipated, based on chemical structure.

 Self-reactive properties 

 (data waiving)

 No potential, based on chemical structure.

 Organic peroxide 

 (data waiving)

 Not a peroxide, based on chemical structure.

 Corrosivity to metals 

 (data waiving)

 Test method not applicable to solids.

 Particle size distribution 

 (OCDE110/ISO13320/laser diffraction in air)

 Median diameter (D50) = 184 μm 

 Thoracic fraction (<10 μm) = 5.8 % 

 Dust particles (<500 μm) = 88.2 %

 Dissociation constant

(literature, titration-like method)

 pKa = 8.56