Registration Dossier

Physical & Chemical properties

Endpoint summary

Administrative data

Description of key information

Appearance/physical state/colour:

On the basis of physical observation the substance 4-(phenylazo)benzene-1,3-diamine was found to be an orange coloured organic powder.

 

Melting point/freezing point:

The melting point determination of 4-(phenylazo)benzene-1,3-diamine (CAS No. 495-54-5) was done following OECD Guideline 102 and according to the metal block capillary method. The test was conducted in replicates and mean melting temperature range was found to be 231.5 °C-235.6°C at 968.9hPa.

 

Boiling point:
The boiling point determination of 4-(phenylazo)benzene-1,3-diamine (CAS No. 495-54-5) was done following OECD Guideline 103 and according to the method of Siwoloboff. The test item does not show string of bubbles upto 305 °C, inferring boiling point to be greater than 300°C.at 970.2 hPa.

 

Density:
The density of test item 4-(phenylazo)benzene-1,3-diamine (CAS No. 495-54-5) was determined following OECD Guideline 109 and according to the The International Pharmacopoeia, Fourth Edition, 2014 using bulk density apparatus. The mean pour density and tapped density of test item was found to be 0.4211 g/cm³ and 0.5410 g/cm³at 29.1°C and 968.6 hPa.

 

Partition coefficient:
The particle size distribution of test item 4-(phenylazo)benzene-1,3-diamine (CAS No. 495-54-5 ) was determined by granulometric analysis with rotap sieve shaker. The particle size distribution was found to be in the range of 150 micron to 10 micron.

 

Vapour pressure:

Vapour pressure of substance 4-(Phenylazo)benzene-1,3-diamine is found to be 0.00020265  Pa at 25°C

Partition coefficient:

The partition coefficient (n-octanol/water) of test substance 4-(phenylazo)benzene-1,3-diamine (CAS No. 495-54-5)was determined as per the HPLC method (OECD Guideline-117). The Log Pow value was found to be 2.7148 ± 0.003 at 25°C

 

Water solubility:
The water solubility determination of test item 4-(phenylazo)benzene-1,3-diamine;CAS No.495-54-5 was done by spectrophotometric method. The water solubility was found to be 348.393 mg/L at 30°C.

 

Surface tension:
In accordance with column 2 of Annex VII of the REACH regulation, the study need only be conducted if surface activity is a desired property of the chemical. The chemical 4-(phenylazo)benzene-1,3-diamine is used for dyeing leather, wool, paper and as a biological stain. For these uses, surface activity is not a desired property. Hence this study was considered for waiver.

 

Flash point:
The flash point determination of 4-(phenylazo)benzene-1,3-diamine (CAS No. 495-54-5)was done following closed cup method using Pensky-Martens flash point apparatus. The test was conducted in replicates and mean flash point was found to be 213.3°C at 968.9hPa.

 

Auto flammability:
4-(phenylazo)benzene-1,3-diamine did not catch fire on being exposed to air at room temperature of 27°Cpressure of 966 hPa. This indicates that 4-(phenylazo)benzene-1,3-diamine is not auto-flammable.

 

Flammability:

The chemical 4-(phenylazo)benzene-1,3-diamine has NFPA Flammability rating reported as 0. This suggests low likelihood of the chemical being flammable. Hence this end point was considered for waiver & the chemical is classified as "Non Flammable" for chemical safety assessment.

 

Explosiveness:
In accordance with column 2 of Annex VII of the REACH regulation, the study does not need to be conducted since there are no chemical groups associated with explosive properties present in the molecule of 4-(phenylazo)benzene-1,3-diamine, except only the azo group. Thus, this end point was considered for waiver and the chemical is considered to be "Non explosive".

 

Oxidising properties:

The study does not need to be conducted because there are no chemical groups present in the molecule which are associated with oxidising properties and hence, the classification procedure does not need to be applied.

 

pH:

The pH determination of test item 4-(phenylazo)benzene-1,3-diamine (CAS No 495-54-5) was done following OECD guideline 122. pH of 1% w/v solution was measured with the help of pH meter and it was observed to be 6.19 at 30 °C.

Additional information

Appearance/physical state/colour:

On the basis of physical observation the substance 4-(phenylazo)benzene-1,3-diamine was found to be an orange coloured organic powder.

 

Other supporting data from from authorative handbook source (Richard J. Lewis, Sr.; SAX Handbook) and authoritative database (Gestis) indicates the substance the substance 4-(Phenylazo) benzene-1, 3-diamine as an organic solid present as white or pale yellow crystals from water.

 

Melting point/freezing point:

The melting point determination of 4-(phenylazo)benzene-1,3-diamine (CAS No. 495-54-5) was done following OECD Guideline 102 and according to the metal block capillary method. The test was conducted in replicates and mean melting temperature range was found to be 231.5 °C-235.6°C at 968.9hPa.

 

Supporting data from authorative handbook and database (Sax handbook and HSDB substance database)indicate that the melting point of 4-(Phenylazo)benzene-1,3-diamine in the range of 118-118.5°C.

 

As the data from lab has K1 reliability and the test was performed using OECD guidelines which has the value of melting point as 231.5 °C-235.6°C, thus considered as key study for the chemical safety assessment.

 

Boiling point:
The boiling point determination of Test item 4-(phenylazo)benzene-1,3-diamine (CAS No. 495-54-5 ) was done as per the test guideline OECD 103. The method followed was

according to Siwoloboff. the test item does not show string of bubbles upto 305 °C, inferring boiling point to be greater than 300°C at 970.2 hPa.

 

Other supporting data from reliable handbook source (SAX handbook) the boiling point of 4-(Phenylazo)benzene-1,3-diamine is determined to be 286°C.

 

As the data from lab has K1 reliability and the test was performed using OECD guidelines which has the value of boiling point as >300°C, thus 300°C is considered as key study for the chemical safety assessment.

 

Density:
The density of Test item 4-(phenylazo)benzene-1,3-diamine (CAS No. 495-54-5 ) was determined following OECD guideline 109 and according to the method recommended in the International Pharmacopoeia, fourth Edition, 2014.The mean pour density and tapped density of the test item was found to be 0.4211 g/cm³ and 0.5410 g/cm³at 29.1°C and 968.6 hPa.

 

Supporting data from reliable handbook source (SAX handbook) the density of 4-(Phenylazo)benzene-1,3-diamine is determined as 1.139.

 

As the data from lab has K1 reliability and the test was performed using OECD guidelines, thus pour density value is considered as key value for the chemical safety assessment.

 

Partition coefficient:

The particle size distribution of test item 4-(phenylazo)benzene-1,3-diamine (CAS No. 495-54-5 ) was determined by granulometric analysis with rotap sieve shaker. The particle size distribution was found to be in the range of 150 micron to 10 micron.

 

Vapour pressure:

From reliable handbook and authorative database the vapour pressure of substance 4-(Phenylazo)benzene-1,3-diamine is found to be 0.00020265 Pa at 25°C.( Handbook of Physical Properties of Organic Chemicals and SRC PhysProp Database)

 

Other supporting study from reliable handbook (SAX) indicate that the Vapour pressure of substance 4-(Phenylazo) benzene-1,3-diamine is 133.32 Pa at 99.8°C.

 

Partition coefficient:

The partition Coefficient n-octanol/water of 4-(phenylazo)benzene-1,3-diamine(CAS No.495-54-5) was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 117 for testing of Chemicals.The reference substances were chosen according to functional similarity with the test substance and calibration graph was prepared. The reference substances were Benzene, Biphenyl, 4 -Acetylpyridine, Toluene, Ethylbenzene, n-Butylbenzene, Naphthalene having Pow value ranging from 0.5 to 4.6 The Log Pow value was found to be 2.7148 ± 0.003 at 25°C.

 

Supporting data from reliable handbook source and database the octanol-water partition coefficient (Log Kow) of 4-(Phenylazo)benzene-1,3-diamine is determined to be 2.13 indicating that the substance is hydrophillic in nature.( Handbook of Physical Properties of Organic Chemicals and SRC phys prop database).

 

Both these values indicates that the substance 4-(phenylazo)benzene-1,3-diamine is hydrophillic in nature which in turn is supported by its water solubility.

 

Water solubility:
The water solubility determination of test item 4-(phenylazo)benzene-1,3-diamine (CAS No. 495-54-5) was done as per the OECD guideline 105 byspectrophotometric analytical method as per OECD 101. The solubility of (4-(phenylazo)benzene-1,3 - diamine of 495-54-5 )in water was found to be 348.393 mg/L at 30°C. This value indicates that the substance is moderately soluble in water.

 

Other supporting data from authorative database/ handbook (HSDB and SRC phys-prop database) also indicates that the test substance 4-(Phenylazo)benzene-1,3-diamine is moderately soluble or soluble in water.

 

Surface tension:
In accordance with column 2 of Annex VII of the REACH regulation, the study need only be conducted if surface activity is a desired property of the chemical. The chemical 4-(phenylazo)benzene-1,3-diamine is used for dyeing leather, wool, paper and as a biological stain. For these uses, surface activity is not a desired property. Hence this study was considered for waiver.

 

Flash point:

The flash point determination of 4-(phenylazo)benzene-1,3-diamine (CAS No. 495-54-5)was done following closed cup method using Pensky-Martens flash point apparatus. The test was conducted in replicates and mean flash point was found to be 213.3°C at 968.9hPa.

 

Other supporting data from secondary source also indicates the flash point of the test substance 4-(Phenylazo)benzene-1,3-diamine as 214.8°C, which supports the selected key value. Both these value indicates that the test substance is not flammable.

 

Auto flammability:
4-(phenylazo)benzene-1,3-diamine did not catch fire on being exposed to air at room temperature of 27°Cpressure of 966 hPa. This indicates that 4-(phenylazo)benzene-1,3-diamine is not auto-flammable.

 

Flammability:

The chemical 4-(phenylazo)benzene-1,3-diamine has NFPA Flammability rating reported as 0. This suggests low likelihood of the chemical being flammable. Hence this end point was considered for waiver & the chemical is classified as "Non Flammable" for chemical safety assessment.

 

Explosiveness:
In accordance with column 2 of Annex VII of the REACH regulation, the study does not need to be conducted since there are no chemical groups associated with explosive properties present in the molecule of 4-(phenylazo)benzene-1,3-diamine, except only the azo group. Thus, this end point was considered for waiver and the chemical is considered to be "Non explosive".

 

Oxidising properties:

The study does not need to be conducted because there are no chemical groups present in the molecule which are associated with oxidising properties and hence, the classification procedure does not need to be applied.

 

pH:

The pH determination of test item 4-(phenylazo)benzene-1,3-diamine (CAS No. 495-54-5 ) was done as per the test guideline OECD 122. The mean pH of the test solution was determined with the help of digital pH meter. The mean pH was found to be 6.19 at 30 °C.