Synthesis And Characterization Of Alkyl-end-capped EO/PO Copolyethers

Ethylene oxide(EO) and propylene oxide(PO) copolymers are widely used as nonionic surfactants which have been found to have widespread industrial uses in detergency, dispersion stabilization, foaming, emulsification, lubrication, high-speed spin finish of Nylon, polyester and viscose fiber, etc. But the exiting of the terminal hydroxyl groups makes the polyethers unstable in chemical or at high temperature, and will be high-foaming when used as surfactants. Alkyl-end-capped polyethers are prepared by reaction of the corresponding fatty alcohol polyglycol ethers with alkyl halide containing from 1 to 4 carbon atoms. Because of the reduce of the hydroxyl groups, the polyethers are thermostable, alkali-resistant, low-foaming, foaming reducing, fast-wetting, and readily biodegradable compared to the Poly(oxyethylene-oxypropylene) monol.The end capping reaction is a Williamson's ether synthesis which can only be carried out in the presence of at least stoichiometric quantities of a strong base, for example sodium hydroxide or potassium hydroxide. The alkyl halide is then added to the reaction product to modify the hydroxyl groups. Compared with the advanced technology of the synthesis of Alkyl-end-capped polyethers, domestic one still has some gap. For example, research on Alkyl-end-capped polyethers is relatively little, insufficiency and high price. In China, Much research has been focused on the synthesis and properties of block copolymers of ethylene oxide and propylene oxide using propylene glycol as an initiator, while research on random copolymers of this kind is relatively little except for our laboratory, so as to researth on Alkyl-end-capped EO/PO random polyethers.In this article, the synthesis and characterization of Alkyl-end-capped copolymers of ethylene oxide and propylene oxide was discussed. Through the research of the reaction conditions, the relationship between structure and property of the polymer, a type of polyether that can be used in Nylon 66 high speed spinning finishes was synthesized. New art for the praparation of Alkyl-end-capped polyethers is also be studied. The main conclusions were showed as following:...