Preparation method of gradient copolymer

Abstract

The invention belongs to the technical field of preparation methods of copolymer and particularly relates to a preparation method of gradient copolymer. The preparation method of the gradient copolymer is good in capacity-increasing effect. The preparation method includes the following steps that 1, dispersion is conducted through magnetic stirring, N2 is firstly introduced into a three-opening flask equipped with a condenser pipe and an N2 injection pipe, then water, RAFT-2 and NaOH are sequentially added, stirred, dissolved and mixed to be uniform, styrene is added, rapidly stirred and pre-emulsified, and heating in a water bath is started; 2, when the water bath is heated to certain temperature, initiator is added, and F6BA monomers are added dropwise at certain speed through a trace sample injection pump; 3, after blue light happens to a system, a heat preservation reaction is conducted, and the reaction is finished, a heat source is removed, stirring continues to be conducted, after emulsion is cooled to room temperature, discharged materials are filtered through a screen, and the polymerization conversion rate is tested through a gravimetric method.

Description

technical field [0001] The invention belongs to the technical field of preparation methods of copolymers, in particular to a preparation method of gradient copolymers. Background technique [0002] The compatibility between the components in the polymer blend system is an important factor affecting the morphology, structure and properties of the blended materials. Adding block or graft copolymers is a common method to improve the compatibility of polymer blends, but the CMC value of block or graft copolymers in homopolymer blends is low, making compatibilization limited. Theoretical studies have shown that copolymers with controllable molecular weight and molecular weight distribution also have a good compatibilizing effect on homopolymer blends. If combined with the effect of fine molecular chain structure, such as gradient chain structure, this gradient copolymer and Compared with block copolymers with the same composition, a higher CMC value will be obtained, which will...

AI Technical Summary

Problems solved by technology

Controlled / "living" radical polymerization (CRP) is considered to be an efficient approach for the preparation of gradient copolymers, where atom transfer radical polymerization (ATRP), nitroxide-mediated polymerization (NMP), reversible addition-fragmentation Chain transfer polymerization (RAFT) has been used for the preparation of gradient copolymers, but the preparation of gradient copolymers by RAFT technology in soap-free emulsion systems has not been reported.