THE PREPARATION OF CHEMICALLY ACTIVE POLYACROLEIN

Abstract

White powdery polyacrolein, of which aldehyde groups were hydrated and chemically inactive, was heated under N2 atmosphere, in order to deprive hydrating water and to regenerate free aldehyde groups. But by heating hydrated aldehyde groups condensed with elimination of water molecule to form chemically stable ether linkage.After the condensation was almost completed, the regeneration of free aldehyde groups occured accompanied by the following simultaneous breaking of ether linkages.Thus, it is difficult to obtain chemically active polyacrolein by heating hydrated polyacrolein.Then another proccedure was proposed. CH (OH) SO3H groups, which are chemically as active as free aldehyde groups, were introduced to hydrated polyacrolein, by steeping the white powdery polyacrolein in SO2 aqueous solution at room temperature. Polyacrolein -CH(OH)SO3H was easily obtained after steeping for 24hrs. But it was impossible, by the easy dissociation of introduced CH(OH)SO3H groups and the formation of ether linkage, to isolate chemically active polyacrolein -CH(OH)SO3H from the aqueous solution.