Il-Wun Shim

Reaction chemistry of palladium acetate complexes in polycarbonate: a comparative study

Abstract Palladium acetate complexes have been incorporated into polycarbonate (PC) films as a dispersion medium using tetrahydrofuran (THF). The resulting light brown-coloured homogeneous films of 10–30 wt.% Pd metal complex concentration are found to be thermally stable up to 150°C, and the relatively electron rich oxygen atoms of ketone groups in polycarbonate molecules are assumed to interact with Pd complexes on the basis of their infrared spectroscopic and thermal analyses. The reaction chemistry of Pd in PC has been investigated by reacting Pd sites with small gaseous molecules such as CO, H 2 , O 2 , NO, and olefins in the temperature range of 25 to 150°C, and various Pd-carbonyls, -hydride, -nitrosyl, and -ethylene species formed in PC are characterized. The treatment of Pd-containing PC film with H 2 gas at 120°C produces small Pd metal particles of ca. 40–330 A in diameter in PC, which show various catalytic reactivities in CO oxidation, NO reduction, dimethyl carbonate formation and hydrogenation of styrene-monomer.

Preparation of Rh-containing polycarbonate films and the study of their chemical properties in the polymer

Abstract RhCl[P(C 6 H 5 ) 3 ] 3 complexes have been incorporated in polycarbonate (PC) as a dispersion medium using cosolvent (THF). The interactions between Rh(I) complexes and polycarbonate polymer molecules are studied by infrared spectroscopy and thermal analysis. The reaction chemistry of Rh in PC films has been investigated by reacting Rh sites in PC with small gaseous molecules like CO, H 2 , D 2 , O 2 , NO, C 2 H 2 , and C 2 H 4 in the temperature range 25∼150°C. Various Rh–carbonyls, –hydride, –nitrosyl, and –superoxo dioxygen species formed in PC films are characterized by infrared spectroscopy. The Rh complexes in PC are easily reduced by reacting them with H 2 gas and such reduction results in the formation of small Rh metal particles of 20∼30 A in diameter in PC. The Rh complexes in PC show interesting catalytic reactivities such as hydrogenation of olefin and acetylene, oxidation of CO, reduction of NO, methanol synthesis from CO or CO 2, and oxidation of alcohol under relatively mild conditions.

Unusual effect of Ru complexes on the permeation of carbon monoxide and oxygen gas mixture through polycarbonate membrane

Abstract 20 wt% RuCl 3 ·3H 2 O-containing polycarbonate membranes are prepared by using co-solvent and using these metal-containing membranes, over 99% of pure oxygen (O 2 ) gas was recovered from a 1 : 1 mixture of O 2 and CO gas mixture at room temperature. Under the described conditions, the Ru complexes are inert to oxygen, but quite reactive to carbon monoxide gas molecules. Very stable Ru-carbonyl species are found to be formed during the gas permeation in the membrane, indicating that there are relatively strong interaction between CO gas molecules and the Ru complexes incorporated into the polycarbonate membrane. Such preferential interactions are believed to give rise to a drastic change in permeation selectivity of a organic polymer membrane.