ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Polymer-supported phase transfer catalysts, which were prepared by immobilizing tributylamine on chloromethylpolystyrene, were characterized by optical microscope, SEM, EPMA, and ESCA. Both optical photograph and electron micrograph showed that the exterior surface of polymer support became wrinkly after immobilization in dry condition. The surface of the triphase catalyst may become smooth after being swelled by solvent. From the ESCA analysis in a depth of about 100 Å, it was found that 46.5% of covalent chloride in chloromethylpolystyrene had reacted with tributylamine and converted to quaternary ammonium chloride. However, the EPMA, which analyzed in a depth of about 1 μm, gave a value of only 31% and the titration method which was for the whole bead gave 14.3%. These results reveal that the catalyst has a higher content of quarternary ammonium chloride in the outer shell. It is concluded that the high activity of this catalyst is due to the fact that it contains both hydrophobic and hydrophilic groups on the exterior surface, and more active species in the outer shell.
Additional Material:
8 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1990.070390805
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