Corn wax oxidates and esterification products
The invention relates to bright corn wax oxidates, to a process for their production and to their use for agricultural or forestry purposes, as an additive in plastic processing, in care products, in printing inks and/or in paints, and to saponified or estered corn wax oxidates produced by saponifying or estering the described corn wax oxidates.
1 . A corn wax oxidate (O) having an acid value measured according to ISO 2114 (2002) of from about 10 mg KOH/g to about 170 mg KOH/g and comprising genuine esters having 46 carbon atoms and genuine esters having 52 carbon atoms, wherein a ratio of the weight percent of genuine esters having 46 carbon atoms to the weight percent of genuine esters having 52 carbon atoms is greater than 1.
2 . The corn wax oxidate (O) according to claim 1 , comprising no more than 5% by weight, based on the total weight of the corn wax oxidate (O), of lignoceric acid.
3 . The corn wax oxidate (O) according to claim 1 , comprising less than 5% by weight, based on the total weight of the corn wax oxidate (O), of polyesters formed from polyhydric alcohols and aliphatic carboxylic acids having 8 to 20 carbon atoms.
4 . The corn wax oxidate (O) according to claim 1 , comprising
a) from 3% to 40% by weight, based on the total weight of the corn wax oxidate (O), of free aliphatic carboxylic acids having 8 to 36 carbon atoms;
b) from 0% to 10% by weight, based on the total weight of the corn wax oxidate (O), of free aliphatic alcohols having 24 to 36 carbon atoms;
c) from 0% to 5% by weight, based on the total weight of the corn wax oxidate (O), of free aliphatic dicarboxylic acids having 10 to 30 carbon atoms;
d) from 30% to 97% by weight, based on the total weight of the corn wax oxidate (O), of genuine esters having 40 to 66 carbon atoms; and
e) from 0% to 30% by weight, based on the total weight of the corn wax oxidate (O) of further natural constituents present in corn wax,
where the sum total of a), b), c), d), and e) is 100% by weight, based on the total weight of the corn wax oxidate (O).
5 . The corn wax oxidate (O) according to claim 1 , obtainable by a process comprising the steps of:
i) providing a corn wax (CW);
ii) providing a mixture (M) of chromium trioxide and sulfuric acid;
iii) performing the oxidation of the corn wax (CW) by reacting the corn wax (CW) with the mixture (M) to obtain a corn wax oxidate (O) reaction mixture comprising an organic phase and an aqueous phase;
iv) ending the reaction and allowing the reaction mixture obtained in step iii) to stand until the organic phase has separated from the aqueous phase;
v) separating off the organic phase;
vi) optionally removing residues containing chromium compounds from the organic phase to obtain the corn wax oxidate (O) in purified form; and
vii) optionally repeating the sequence of steps ii) to vi) using the corn wax oxidate (O), optionally in purified form, in place of the corn wax (CW).
6 . The corn wax oxidate (O) according to claim 5 , wherein a weight ratio of total chromium trioxide used to corn wax (CW) used is from 1:6 to 3:1.
7 . The corn wax oxidate (O) according to claim 5 , wherein
the mixture (M) comprises concentrated sulfuric acid with a sulfuric acid content of at least 90% by weight; and
the concentration of chromium trioxide in the mixture (M) is from 50 g/L to 200 g/L.
8 . The corn wax oxidate (O) according to claim 5 , wherein the corn wax (CW) comprises up to 25% by weight of polyesters formed from polyhydric alcohols and aliphatic carboxylic acids having 8 to 20 carbon atoms.
9 . The corn wax oxidate (O) according to claim 5 , wherein the reaction in step iii) is carried out while stirring at a temperature of 70° C. to 200° C. for a period of at least 30 minutes to 5 hours, at a stirrer speed of from 100 to 500 rpm, and in the absence of oxidation promoters.