messages: Dans le but d'éviter la sursaturation du milieu réactionnel en sel quaternaire (I), on impose pendant l'étape (b) un rapport molaire d'introduction d'eau sur l'agent quaternisant (III) compris entre 2,2 et 3,7.
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  I need a translation of this text from french into english, please.
messages: user
messages: In order to avoid supersaturation of the reaction mixture with quaternary salt (I), a molar ratio of addition of water to the quaternizing agent (III) of between 2.2 and 3.7 is imposed during stage (b).
messages: assistant