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This article describes the separation of mixtures of fatty acid salts using a new organic solvent nanofiltration membrane based on polydicyclopentadiene (PDCPD). Mixtures of free fatty acids could not be separated by the membranes because they permeated at similar rates. When triisobutylamine was added to the fatty acids, the cis-fatty acid salts (oleic, petroselinic, vaccenic, linoleic, and linolenic acid) had slower permeation though the membranes than saturated (stearic acid) and trans-fatty acid (elaidic acid) salts. The reason for the difference in permeation was due to the formation of stable salt pairs between the amine and fatty acids that increased their cross-sectional areas. The fatty acid salts derived from saturated and trans-fatty acids were smaller than the critical area cutoff for the PDCPD membranes, so they readily permeated. In contrast, the fatty acid salts derived from the cis-fatty acids had critical areas larger than critical area cutoff of the PDPCD membranes and had slowed permeation. The partitioning coefficients of fatty acids and fatty acid salts were investigated to demonstrate that they were not responsible for the difference in permeation. The use of pressure was investigated to greatly accelerate the permeation through the membranes. For a solvent mixture of 35/65 (v/v) toluene/hexanes, the permeation of solvent was approximately 39 L m(-2) h(-1). This value is similar to values reported for permeation through membranes used in industry. The separation of a mixture of fatty acids based on the composition of soybean oil was investigated using pressure. The saturated fatty acid salts were almost completely removed from the cis-fatty acid salts when iBu(3)N was used as the amine to form the salt pairs. The separation of the cis-fatty acids found in soybean oil was investigated with Pr(3)N as the amine. The oleic acid salt (oleic acid has one cis double bond) preferentially permeated the membrane while the linoleic (two cis double bonds) and linolenic (three cis double bonds) salts were partly retained. The separation of fatty acids using membranes may have real applications in industry to purify fatty acids on a large scale.

Thimbles composed of polydicyclopentadiene retained Pd and phosphines used in Buchwald-Hartwig and Sonogashira coupling reactions but allowed the products to permeate. The products were isolated in high yields on the exteriors of the thimbles with no detectable contamination from phosphine and with Pd loadings as low as < 5.5 ppm.

Macroscopic, hollow thimbles were synthesized from dicyclopentadiene with the Grubbs second generation catalyst at a monomer:catalyst loading of 10,000:1. A series of Buchwald-Hartwig and Sonogashira coupling reactions were completed on the interior of the thimbles followed by extraction of the product to the exterior using hexane. In all examples, palladium was retained by the membranes at ≥99.9% levels. Both polar and apolar molecules with molecular weights from 101 to 583 g mol-1 permeated these thimbles with values for flux of 10-5 to 10-6 mol cm-2 h-1 , but selected molecules did not permeate them and had flux values 10 4 to 10 5 times slower. The difference in flux was large between molecules that permeated and those that did not permeate, but no trend was observed that correlated flux with molecular weight or hydrophobicity. Rather, molecules that did not permeate the membranes had large cross-sectional areas that led to low rates of diffusion within the highly cross-linked polydicyclopentadiene membranes. Membranes were fabricated from the ring opening metathesis polymerization of dicyclopentadiene with the Grubbs first generation catalyst at a monomer:catalyst loading of 5,000:1. Mixtures of fatty acid salts were separated using polydicyclopentadiene membranes. Mixtures of fatty acids could not be separated by the membranes, but when triisobutylamine was added to the fatty acids, cis-fatty acid salts had slower permeation though the membranes than saturated and trans-fatty acid salts. Oleic, petroselinic, vaccenic, linoleic, and linolenic acid salts with triisobutylamine had slower permeation relative to the permeation of stearic and elaidic acid salts. Organic catalysts were retained from organic molecules using nanoporous polydicyclopentadiene membranes. Acid or base was added to organic catalysts that increased the critical areas of the organic catalysts to the size range (>0.5 nm 2) where PDCPD membranes could retain them. The catalysts by themselves were too small to be v TABLE OF CONTENTS LIST OF TABLES ……………………………………………………………………….ix LIST OF FIGURES .

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