Isostearic acid, esters with methyl α-D-glucoside

Endpoint summary

Additional information

The test substance Isostearic acid, esters with methyl α-D-glucoside is an organic compound, which is characterized as a viscous, slightly yellow liquid. The melting point of the test substance was not observed in the temperature range from -90 °C to 360 °C when tested according to OECD Guideline 102 (Melting point / ) and EU Method A.1 (Melting / Freezing Temperature). According to OECD Guideline 103 (Boiling point/boiling range) and EU Method A.2 (Boiling Temperature) a boiling point was also not observed below 360°C (633.15 K). Based on observations during the test it is supposed that in the temperature region between 75 and 175°C a small fraction of the test substance evaporated. After the experiment, a black coloured liquified residue remained in the sample container, which indicated that the test substance had reacted or decomposed. The density and relative density were determined to be 1 g/cm³ and 1 at 20 °C, respectively. According to REACH Regulation (Annex VII, 7.14, column II), the study on granulometry needs not to be done if the substance is marketed or used in a non solid or non granular form. Based on extrapolation at 20 °C the vapour pressure was calculated to be 1.47 x 10E-3. The vapour pressure was determined by comparison of its weight loss with the weight loss of a reference substance (hexachlorobenzene) at 100°C, 120°C, 130°C and 140°C. Since the weight loss of the test substance was lower then the weight loss of hexachlorobenzene at the same temperatures, it was concluded, that the test substance has a lower vapour pressure then hexachlorobenzene.

The n-octanol/water partition coefficients of the components of Isostearic acid, esters with methyl α-D-glucoside were investigated in a study conducted according to OECD Guideline 117 and EU Method A.8 (HPLC-Method). Since it was not possible to elute the test substance under isocratic conditions with a mobile phase of 75/25 (v/v) methanol/water, a gradient was applied directly after the isocratic run in order to rinse the test substance off the column. Due to the limited solubility of the test substance in aqueous mixtures the test solution (stock solution: 1456 mg/L) was used undiluted. The log Pow values were determined to be 0.3 for most likely methyl glucoside and > 6.5 for all other components.

The water solubility was determined according to OECD Guideline 105 (Water Solubility, 1995) and EU Method A.6 (Water Solubility, 2008). In general, two methods are available for the determination of the water solubility (flask method and column elution method). In a preliminary test, the water solubility of the test substance was 10E-2 g/L. Since it proved not possible to develop a sensitive analytical method for the determination of the low substance concentrations in samples from this test, performing a test based on the flask method in combination with visual interpretation was the only possible alternative. To support the visual results TOC analysis was performed after centrifugation for 5 min at 3500 g and 20°C. Visual interpretation of the test results was conducted by comparison: Test substance was stirred with distilled water at nominal concentrations of 0.5, 1.0 and 10 mg/l at 19.7 +/- 0.5°C for 72 hours. Since after this period all three test solutions revealed undissolved, the solubility of the test substance was determined to be 0.5 mg/l. The pH of the aqueous samples was 7.4 - 8.3. As the results of the TOC analysis were not unambiguous, indicating, that an excess of test substancewas not completely removed from the test solutions only the results from the visual interpretation were reported.

According to REACH Regulation (Annex VII, 7.6, column II), the study on surface tension needs not to be performed if the water solubility is <1 mg/L at 20°C. It was concluded that Isostearic acid, esters with methyl α-D-glucoside has no flash point. A test was investigated according to EU Method A.9 (Flash-Point, 2008), ISO 2719:2002 (Determination of flash point - Pensky-Martens closed cup method, 2002), and ASTM D93 (Standard test methods for flash point by Pensky-Matens Closed CUP Tester, 2002). No flash-point was observed up to a temperature of 286°C (atmospheric pressure 101.3 - 102.1 kPa, attempt was made to ignite the vapour of the test substance every 2°C, starting at 24°C). At the temperature of 286°C the experiment was stopped due to severe smoke generation. Smoke was observed from 176°C onwards. The smoke was not ignitable.
The auto-ignition temperature of Isostearic acid, esters with methyl α-D-glucoside was determined to be 415 °C at 1008.2-1032.5 hPa. According to REACH Regulation (Annex XI, 1.), the study on flammability needs not to be done if the available data are sufficient for assessment. For liquids the relevant endpoint is the flash point. According to REACH Regulation (Annex VII, 7.11, column II), the study on explosiveness needs not to be done if the test substance does not contain chemical groups indicating explosive properties. According to REACH Regulation (Annex VII, 7.13, column II), testing of oxidising properties needs not to be conducted as the test substance does not contain any structural groups known to be correlated with a tendency to react exothermically with combustible material. The test substance dissolved in methanol was stable for at least 1 day at room temperature. A pH of 7.4 was found at a test substance concentration of 0.5 mg/L and a pH of 8.3 at a test substance concentration of 10 mg/L at 19.7°C each. The pKa values of the test substance components were estimated using the Perrin calculation method (pKaLc 5.0, module in Pallas 3.0, CompuDrug International). The calculation yielded pKa values ranging from 13.1 to 17.9 for methyl glucoside and pKa values ranging from 12.9 to 16.5 for the monoester.