A method for preparing polyacrylate by single electron transfer-living radical polymerization

Abstract

The invention discloses a method for preparing polyacrylate by single electron transfer-living radical polymerization. The method comprises the following steps of adding a dispersant aqueous solution into deionized water, adding a pH conditioning agent, a catalyst, a monomer and an initiator into the dispersant aqueous solution at a temperature of 10 to 60 DEG C for a reaction lasting for 10min-10h, stopping stirring, removing water in the reaction system, putting the product into a vacuum drying oven, and carrying out drying at a temperature of 20 to 60 DEG C to constant weight so that the active polyacrylate product is obtained, wherein a mole ratio of the monomer, the initiator, the pH conditioning agent to the catalyst is (10-4000): 1: (1-40): (1-30); a mass ratio of the dispersant to the monomer is (700-50000ppm): 1; and a volume ratio of the monomer to water is 1: (1-20). The method can realize synthesis of the molecular weight-controllable active polyacrylate at a room temperature or a lower temperature. The polyacrylate product can be used as a macro-molecule initiator, and sequentially initiates polymerization of other monomers so that an ABA segmented copolymer is produced. The method has the advantages of fast polymerization rate, high monomer conversion rate, strong controllability and environmental friendliness.

Description

technical field [0001] The invention relates to a method for preparing polyacrylate by single electron transfer-living free radical polymerization. The method overcomes the shortcomings of traditional living free radical polymerization technology and provides a The agent is a reaction system, and a method for preparing active acrylic polymers at room temperature through a single electron transfer-living radical polymerization (SET-LRP) mechanism. Background technique [0002] Acrylate rubber (ACM) has been widely used in automotive oil seals and other sealing rubber products that require oil resistance and temperature resistance due to the saturation of the main chain structure and the polarity of the side chain ester group. In addition, acrylate rubber is used in PVC impact resistance Modified and PVC thermoplastic elastomers are also widely used. Among synthetic rubbers, ACM is cheaper than silicone rubber and fluororubber, and is more resistant to heat, oil and aging tha...

AI Technical Summary

Problems solved by technology

However, ATRP uses transition metal salts with low oxidation states as catalysts, which have the disadvantages of being easily oxidized, requiring a large amount of catalyst, and troublesome post-treatment, which limits the wide application of ATRP.

The dithioester derivatives in RAFT polymerization are highly toxic, and may also cause the polymer to have a certain color and odor. Their removal or conversion is difficult. In addition, free radicals are easy to cause chain termination and RAFT commercial reagents are difficult to obtain.

For the iniferter method, the cleavage rate of the iniferter reagent at the end of the polymer chain is relatively slow, but due to the continuity of the free radicals, the reaction rate of the growth of the monomer is faster, which will lead to the broadening of the molecular weight distribution of the polymer, making the polymerization possible. bad control

NMP polymerization often requires high temperature. In addition, the disproportionation termination between the growing chain radical and the nitrogen oxide radical during the polymerization process also affects the controllability of the reaction, which limits its industrialization and continued development.

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