Acrylaldehyde

Endpoint summary

Additional information

Acrolein is a colorless or yellowish liquid at 1013 hPa and 20 °C. It has a melting point of -87 °C and a boiling point of 53 °C at 1013 hPa. The density is 0.84 g/cm³ at 20 °C. According to Regulation (EC) 1907/2006 (REACH) (Annex VII, column 2), the study on granulometry does not need to be performed if the substance is market or used in a non solid or non granular form. Acrolein is a liquid under standard conditions. Acrolein has a vapour pressure of 293 hPa at 20 °C. Calculated n-octanol/water partition coefficients log Kow lie in the range between -0.68 and +1.02 while the measured values ranged from -1.1 to +0.9. The reported water solubilities are in the range between 206 and 270 g/l at 20 °C. Acrolein is miscible with lower alcohols, ketones, benzene, diethyl ether, and other common organic solvents. The experimentally determined surface tension of pure acrolein is 27.6 mN/m at 20 °C. The surface tension of an aqueous acrolein solution (<1 g/l) is not available. According to Regulation (EC) 1907/2006 (REACH) (Annex VII, column 2), a study on surface tension does not need to be conducted, because based on the structure surface active properties are not to be expected or predicted.

The flash point of acrolein was determined to be -26 °C using the closed cup method and -18 °C using the open cup method. In deviation from the cited classification in the international reports, acrolein must be regarded as a highly flammable liquid according to EU Directive 67/548/EEC and as a flammable liquid (category 2) according to GHS, based on the flash point and the cut off values. The autoignition temperature is in the range between 220 and 234 °C. The flammability limits of acrolein vapour are 2.8 to 31% by volume. Data on explosive properties are not available. Based on the structure, there are no chemical groups associated with explosive properties present in the molecule. Experimental determination is not considered necessary (see EU RAR). Therefore further testing is scientifically unjustified and according to Regulation (EC) 1907/2006 (REACH) (Annex VII column 2) a study on explosive properties does not need to be conducted. No data on oxidation potential, on stability in organic solvents and identity of relevant degradation products, and reactivity towards container material are available. In a study conducted according to DIN EN ISO/IEC 17025 the Self Accelerating Decomposition Temperature (SADT) of acrolein was determined to be 90 °C. Despite the decomposition energy of -1800 J/g acrolein has not to be considered for the transport class 4.1 'self reactives' due to the determined SADT.

Sunlight, air, heat, peroxides, radicals, mineral acids, bases catalyse polymerisation of acrolein. Therefore, acrolein is stabilized using hydroquinone to inhibite polymerisation. A 10 % aqueous solution of acrolein has a pH of 6.0 at 25 °C. According to REACH VO (Annex IX, column 2), a study on the dissociation constant does not need to be done; if from scientific point of view testing is not possible. The substance has no functional group able to dissociate or make acid/base reactions in water; therefore a study on dissociation constant does not need to be conducted.

Acrolein has a dynamic viscosity of 0.35 mPa * s at 20 °C. The conversion factors at 1013 hPa and 20 °C are: 1 mg/m³ = 0.43 ppm; 1 ppm = 2.328 mg/m³ and the odor perception and recognition threshold are 0.07 mg/m³ and 0.48 mg/m³, respectively.