Dibutyl phthalate
- Phthalate
- DBP
- Butyl phthalate
- Elaol
- Dibutylbenzene -1 ,2- dicarboxylate
P03BX03
Colorless to yellowish liquid
Liquid
1.05 g · ml -1
-35 ° C
340 ° C
- 0.026 μbar (20 ° C)
- 0.07 μbar ( 30 ° C)
- 0.755 μbar ( 50 ° C)
Practically insoluble in water (11 mg · l-1 at 20 ° C)
Risk
7500 mg · kg -1 ( LD50, rat, oral)
Template: Infobox chemical / molecular formula search available
Dibutyl phthalate ( DBP abbreviation ) is a chemical compound, a colorless, oily liquid with a faint aromatic odor. It is an ester of 1-butanol and phthalic acid and belongs beside phthalate, di -iso- nonyl phthalate and diethyl phthalate to the group of phthalates. Industrially used as a plasticizer.
Representation and extraction
The technical production of dibutyl phthalate is carried out in a two-step synthesis of phthalic anhydride, and n-butanol. The first step is a rapid alcoholysis to Phthalsäurehalbester. The second esterification proceeds as an equilibrium reaction and requires the use of slower, and acid catalysts for conversion completion, the distillative removal of the water formed.
Properties
Physical Properties
Dibutyl phthalate is a colorless liquid having a melting point of -35 ° C. The boiling point at atmospheric pressure is 340 ° C. The enthalpy of vaporization is 91.7 kJ · mol here -1. The vapor pressure curve is given by Antoine in the temperature range of 398.8 K to 475.2 K as log10 (p) = A- ( B / ( T C )) ( p in bar, T in K) with A = 4.30568, B = 2083.175 and C = -131.7. The heat capacity at 25 ° C 476 J · mol -1 · K -1 and 1.71 g · J -1 · K -1. The compound is only slightly soluble in water with 11 mg · l -1.
Safety characteristics
Dibutyl formed only at higher temperatures flammable vapor -air mixtures. The compound has a flash point at 157 ° C. The explosion range is between 0.1 vol % for the lower explosive limit ( LEL) and 1.97 vol % for the upper explosive limit ( UEL). Will be assigned in the explosion group IIA. The ignition temperature is 400 ° C. The fabric falls within the temperature class T2. The electrical conductivity is relatively low at 1.8 · 10-7 S · m -1 ( 30 ° C). When burning, irritating, corrosive and toxic fumes are formed.
Use
DBP is mainly used as plasticizers for PVC or as an absorbent ( washing liquid ) for the purification of gas mixtures, and organic compounds. Furthermore, it is used as an additive in drugs cases, so that the ingredients not dissolve in the stomach, but only in the intestine. These were considered, inter alia, medicines for colds, bronchitis, asthma, sleep disorders, high cholesterol and iron deficiency.
Toxicology
Inhalation or ingestion can lead to health and there are temporary problems such as dizziness, nausea, headache etc.. Ingestion can cause respiratory, digestive tract and eye irritation: eg burning, scratching. Dibutyl phthalate acts in animal studies on development, reproduction and embryotoxic. The European Union classifies dibutyl phthalate as " toxic for reproduction " and has for the daily intake of a TDI ( " tolerable daily intake " ) of 10 micrograms per kilogram of body weight set (since July 2005, previously 100 micrograms). The World Health Organization (WHO ) classifies DBP as " fruit and developmental toxicity " one. It is very toxic to aquatic organisms and may cause long-term adverse effects - it is hazardous to water ( WGK 2) and a marine pollutant.
In baby products, cosmetics and toys DBP is banned under the Cosmetics Ordinance and the Commodities Regulation. In the latest draft of the Directive 2002/95/EC RoHS dibutyl phthalate is added to the banned substances.