| abstract |
a) Acrylic acids are in the range of 0.1 and 2.0 moles, based on the total molar amount of aldehyde, maleic acid and maleic anhydride, at least one amine of group S selected from the group consisting of i) alkylene polyamine of the formula II ## STR3 ## (II), v n m R.sup.3 is water to or c. is alkylene amine, ii) o- and m-toluidine, and iii) an alkenolamine of the general formula V, HO-R, 7, 7-NH2. (V), in n m R.sup.7.n. (b) the crude acrylic acid so treated is maintained at 25 and 100 degC for 15 seconds and 150 hours; to column distillation, d) simultaneously to column distillation n of 0.01 and 1.0 mole of at least one amine of group P selected from the group consisting of o-, m- and p-phenylenediamine, 4 -nitrophenylhydrazine, 2,4-dinitrophenylhydrazine, phenylhydrazine, hydrazine and aniline and e) crude acrylic acid treated with amine of group S and P is distilled by distillation of \ t |