Patent · US Expired

Process for the preparation of an aqueous solution of unsaturated quaternary ammonium salts

US4745214A · kind A · utility

8Cited by
1References
40Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 20, 1986
Grant dateMay 17, 1988
Priority date
Expiry dateJun 20, 2006

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC07C213/08
  • WIPO fieldOrganic fine chemistry
  • WIPO sectorChemistry

Abstract

For the preparation of an aqueous solution of unsaturated quaternary ammonium salts of the formula (I): EQU H.sub.2 C.dbd.C--(R.sub.3)C(O)--A--R.sub.4 --N.sup..sym. (R.sub.1)(R.sub.2)(R).X.sup..crclbar., e.g., methacryloyloxyethyltrimethylammonium chloride PA1 the steps of: PA1 (a) reacting a (meth)acrylic monomer, e.g., dimethylaminoethyl methacrylate in a closed reactor, in the presence of a polymerization inhibitor, e.g., 3,5-ditert-butyl-4-hydroxytoluene, with 5 to 20% of the weight quantity of quaternizing agent, e.g., methylchloride, required for the reaction, wherein the latter agent is introduced into the reactor continuously, PA1 (b) adding water and the remainder of the quaternizing agent continuously until the required concentration of quaternary ammonium salt in water is obtained, PA1 (c) maintaining the temperature at a value of between 30.degree. and 60.degree. C. during the stages (a) and (b), and PA1 (d) maintaining a stream of gas containing oxygen in the reaction mixture during the stages (a) and (b) and especially as the end of the reaction approaches, such that the volume ratio of gas at the reactor outlet to the oxygen introduced at the inlet of this same react…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.