Isophthaloyl dichloride

Endpoint summary

Additional information

The test substance (CAS No. 99-63-8) is a solid. The melting point is 45ºC, measured using a capillary apparatus. The boiling point is 272ºC and was measured according to ASTM Method D1120. Bulk density is 0.82 g/mL at 21ºC and was measured according to ASTM method No. E-727. Granulometry measurements have been conducted. Approximately 0.78% of the particles were less than 105 µm by sieving. Particle-size distribution measurements of the particles that passed through the sieve demonstrated approximately 0.2% of the total particles were less than 13.8 µm. The vapour pressure is 0.289 Pa at 20ºC and was measured according to OECD Guideline 107 by the spinning rotor method. The octanol-water partition coefficient experiment was waived since it was technically not feasible. In accordance with Section 2 of REACH Annex XI, with reference to the guidance mentioned in REACH Art 13(3) the test guidance "ECHA guidance on Information requirements and chemical safety assessment Chapter R.7a Endpoint specific guidance" needs to be respected. This guidance indicates that this study does not need to be conducted since the test substance is hydrolytically unstable at pH 4, 7 and 9 (t ½ < 12 hr). Therefore, data has been provided for the primary degradate, isophthalic acid. The water solubility measurement was waived. In accordance with Column 2 adaptation statement of REACH Annex VII, information requirement section 7.7, this study does not need to be conducted as the test substance is hydrolytically unstable at pH 4, 7 and 9 (t ½ < 12 hr). Therefore, the water solubility will be based on the primary degradate, isophthalic acid. The surface tension measurement was waived. In accordance with Column 2 adaptation statement of REACH Annex VII, information requirement section 7.6, this study does not need to be conducted since surface activity is not a desired property of the molecule. No flash point measurement was conducted. In accordance to REACH Annex XI Section 2, with reference to the guidance mentioned in REACH Art 13(3) the test guidance "ECHA guidance on Information requirements and chemical safety assessment Chapter R.7a Endpoint specific guidance" needs to be respected. This guidance indicates that this study does not need to be conducted for substances that are solids or gases at room temperature. No auto-ignition study was conducted. In accordance with Column 2 adaptation statement of REACH Annex VII, information requirement section 7.12, this study does not need to be conducted for solids with melting points less than 160°C. The test substance did not ignite during the full 2 minutes of heating when tested according to EC Method A.10. Therefore, the material is not highly flammable. The test substance is non-explosive. In accordance with Column 2 adaptation statement of REACH Annex VII, information requirement section 7.11, explosivity testing does not need to be conducted based on a structural assessment of the substance. Examination of the structure indicates that there are no groups associated with explosive properties. The test substance is non-oxidising. In accordance with Column 2 adaptation statement of REACH Annex VII, information requirement section 7.13, measurement of oxidising properties does not need to be conducted based on structural assessment of the substance. The substance contains no oxidising groups. Measurement of stability in organic solvents was waived. In accordance with REACH Annex XI Section 2, with reference to the guidance mentioned in REACH Art 13(3) the test guidance "ECHA guidance on Information requirements and chemical safety assessment Chapter R.7a Endpoint specific guidance" needs to be respected. This guidance indicates that this study does not need to be conducted since the stability in organic solvents is not considered critical. This would be assessed in individual studies where organic solvents are used. The dissociation constant measurement was waived. In accordance with Column 2 adaptation of REACH Annex IX, information requirement section 7.16, this study does not need to be conducted as the test substance is hydrolytically unstable at pH 4, 7 and 9 (t ½ < 12 hr). Therefore, the dissociation constant will be based on the primary degradate, isophthalic acid. Measurement of viscosity is not required. In accordance to REACH Annex XI Section 2, with reference to the guidance mentioned in REACH Art 13(3) the test guidance "ECHA guidance on Information requirements and chemical safety assessment Chapter R.7a Endpoint specific guidance" needs to be respected. This guidance indicates that viscosity measurement is only relevant to liquids.

Due to the instability of the test substance in water, selected physical and chemical properties of the main degradation product (CAS No. 121-91-5, Isophthalic acid) are provided. The vapour pressure of the degradation product was calculated as 3.5E-6 Pa at 25ºC (MPBPVPWIN v 1.43). At environmentally relevant pH, the degradation product will exist predominantly in its anionic form. The logD, apparent partition coefficient D for dissociative systems is a more appropriate description of the complex partitioning equilibria. The logD value, as computed by ACD Labs v11.0, provided an estimate of -2.34 at pH 7. This is the preferred logD value for use. The water solubility of the degradation product at 25ºC, representative of anionic form, is reported as 5400 mg/L. The degradation product has 2 pka values, the pKa1 value is 3.70 and a pKa2 value of 4.60 at 20ºC . Therefore, the degradation product will exist as the anionic species in the environment.