Date of Award

Summer 1980

Document Type

Thesis - Restricted

Degree Name

Master of Science (MS)

Department

Chemistry

First Advisor

Regen, Steven

Second Advisor

Steinmetz, Mark

Third Advisor

Feng, Paul Y.

Abstract

Microporous polymeric catalysts were made by copolymerization of different mole ratios of styrene, divinylbenzene and vinylbenzylchloride ( 60: 40 mixture of meta: para ) and functionalization of the resultant chloromethylated polymers by quaternization with tri-n-butylphosphine. Five series of 20%, 10%, 5%, 2% and 1% crosslinked resins with varying degrees of ring substitution were thus obtained. A pure-para substituted microporous resin with 1 % crosslinking was synthesized in similar manner. Macroreticular analogues based on commercial XAD-2 and XAD-4 resins were made by chloromethylation of the polystyrene beads and subsequent quaternization with tri-n-butylphosphine. Efficiency of these triphase catalysts was determined by carrying out kinetic experiments on simple nucleophilic displacement of chloride ion on n-decylmethanesulfonate at 900C under both vigorously stirred and unstirred conditions. Evaluation of the efficiency data indicate that (1) efficient catalysts possess a low degree of crosslinking, (2) higher efficiency may be achieved by reducing the percent of ring substitution, (J) highly crosslinked macroreticular-basedtriphase catalysts are not catalytically more active than the lower crosslinked microporous counterparts, (4) no apparent advantage is given by a microporous resin made with pure-para vinylbenzylchloride which is expected to be more efficient than the corresponding resin made from a mixture of meta-para (60:40 ) vinylbenzylchloride. Although many of the microporous resins showed increased activity upon stirring, some did not indicate any dependency on stirring. Further investigation is required to clarify the influence of stirring on the catalytic activity of the microporous-based triphase catalysts.

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