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US 5,053,539 AGranted
Methylene-crosslinked polyarylamine and process for preparing same
AssigneeMitsui Toatsu Chemicals, Inc.
InventorsNaoyuki Yano, Tatsuya Nagayoshi, Takashi Nagou, Zunzi Tashima, Noritoshi Ishida, Hiroyuki Itoh, Katsuyuki Nagamatsu
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Abstract
A methylene-crosslinked polyarylamine is disclosed which contains a less amount of N-methylmethylenedianiline. A process for continuously preparing this kind of methylene-crosslinked polyarylamine is also revealed which comprises reacting aniline with formalin in the presence of hydrochloric acid under specific reaction conditions.
Claims2
A process for preparing a methylene-crosslinked polyarylamine by reacting aniline with formalin in the presence of hydrochloric acid under the following conditions (a), (b), (c) and (d):
- (a) the amount of hydrochloric acid is in the range of from 0.1 to 0.5 mole per mole of aniline;
- (b) the amount of aniline is in the range of from 1.5 to 4.0 moles per mole of formalin;
- (c) the reaction is divided in at least four stages, and
- the reaction in the first stage is carried out at 20 to 50.degree. C. in a water/aniline ratio in the range of from 1.3 to 2.5 moles,
- the reaction in the second stage is done at 40 to 70.degree. C. in a water/aniline ratio in the range of from 1.9 to 5.0 moles,
- the reaction in the third stage is done at 50 to 90.degree. C. in a water/aniline ratio in the range of from 2.4 to 5.7 moles, and
- the reaction in the last stage is done at a temperature of 110.degree. C. or more;
- and
- (d) formalin is divided into 3 or more stages and used in the reactions in the respective stages.
6 more elements
Dependencies are inferred from the claim text.