Di(ar)alkyl derivs of cresol as polymerstabilisers

摘要

derivs. of p-cresol of formula: (where R is 4-12 C alkyl or -CH(C6H5)CH3) are obtained by alkylation of phenol with a 4-12 C alkene or styrene at 50-150 degrees C (and pref. at 2-50, esp. 3-15 atmos. pressure) using 0.1-5 wt.% Al as catalyst, followed by reaction at 20-100, pref. 50-80 degrees C, with formaldehyde and dimethylamine (or its reaction product, (CH3)2N-CH2-N(CH3)2), and finally hydrogenating the formed N,N-dimethyl-(3,5-di(ar)alkyl-4-oxybenzyl)-amine at 80-200, pref. 120-140 degrees C and a flow rate of 0.1-21. H2 per hr., using 1-5 moles H2 per mole oxybenzylamine and a Ni-contg. catalyst. Process is economical and selective, and products are thermal and oxidation stabilisers for polymers.