Potassium propyl hydroxybenzoate

Synonyms potassium propyl hydroxybenzoate propyl 4-hydroxybenzoate potassium salt. 

Potassium propyl 4-oxidobenzoate. See Potassium propylparaben Potassium propylparaben CAS 84930-16-5 EINECS/ELINCS 284-597-5 Synonyms Potassium propyl 4-oxidobenzoate n-Propyl-4-hydroxybenzoate potassium salt Propylparaben, potassium salt Definition Potassium salt of propylparaben Empirical C10H12O3 K... 

Boil about 01 g with 50 ml of N sodium hydroxide for thirty minutes under reflux. Cool, add 50 ml of 01N bromine and 10 ml of concentrated hydrochloric acid. Allow to stand for half an hour, shaking repeatedly during the first fifteen minutes, add 2 g of potassium iodide and titrate the liberated iodine with O IN sodium thiosulphate. 1 ml of 0 1 N bromine == 0 002536 g methyl hydroxybenzoate, CgHgOa 0 002902 g sodium salt of the methyl ester 0 003003 g propyl hydroxybenzoate, C10H12C3, and 0 003370 g sodium salt of the propyl ester. 

Annex III lays down the conditions of use for permitted preservatives and antioxidants, with lists of foods and maximum levels in each case. Part A lists the sorbates, benzoates and p-hydroxybenzoates, E 200-E 219 part B lists sulphur dioxide and the sulphites, E 220-E 228 part C lists other preservatives with their uses, including nisin, dimethyl dicarbonate and substances allowed for surface treatment of certain fruits, E 249 potassium nitrite, E 250 sodium nitrite, E 251 sodium nitrate and E 252 potassium nitrate, E 280-E 283 propionic acid and the propionates part D lists the antioxidants E 320 butylated hydroxyanisole (BHA), E 321 butylated hydroxytoluene (BHT), E 310 propyl gallate, E 311 octyl gallate, E 312 dodecyl gallate, E 315 eiythorbic acid and E 316 sodium erythorbate. 

See Potassium propylparaben Propyl-4-hydroxybenzoate, sodium salt Propyl-p-hydroxybenzoate, sodium salt. See Sodium propylparaben... 

The Kolbe-Schmitt reaction of potassium phenoxide with CO2 at 200 °C gives an 80% yield of p-hydroxybenzoic acid, which is used in the form of the propyl and butyl esters as a preservative in cosmetics and pharmaceuticals. 

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