Effects of enchained ester groups on the living carbocationic polymerization of vinyl ethers
Year: 2012
Type: dissertation
Abstract: A series of chloro - substituted 4-(ethenyloxy)butyl benzoate and acetate monomers were polymerized in toluene at -20 and 4o C using an HCl etherate / ethylaluminum dichloride (EtAlCl2) initiator system in the presence and absence of an externally added esters. The systems were evaluated in accordance with established criteria to determine the degree of “livingness” of each system in the presence and absence of the added ester. The effects of the enchainment of the of the ester moiety was studied by comparison with the polymerization characteristics of 4-(ethenyloxy)butane in the presence and absence of the externally added ester corresponding to the enchained ester moiety. The effect of the “intramolecular” ester on the living nature of the system was studied and it was determined that the enchained ester moiety is less effective in inducing a living system than the equivalent ester added externally. Further, it was determined that the degree to which an enchained or externally added ester is able to induce “livingness” in a system is directly proportional to the pKa of the conjugate carboxylic acid of the ester.
Author: Walter Shepherd
Language: English
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W1585490608