The anionic polymerization of 4-methylstyrene results in a linear poly(4-methylstyrene), whose substoichiometric bromination with Br 2 converts a portion of 5-18% of the -CH 3 units into -CH 2 Br groups, which were then reacted with (1-Ad) 2 PH to synthesize a polymer loaded with sterically demanding and electron-rich -CH 2 P(1-Ad) 2 groups as the respective air-stable phosphonium salt. Palladium complexes with the phosphinated polymer are efficient catalysts for carbon-carbon coupling reactions of the Sonogashira, Suzuki, and Heck type with aryl chlorides and bromides. The molecular weight of the respective phosphines in the range of 5-35 kDa does not have a significant effect on the catalytic performance. Such polymer-enlarged catalysts are suitable for separation over a solventresistant nanofiltration membrane composed of a dense poly(dimethylsiloxane) (PDMS) layer cast on a porous sublayer of poly(acrylonitrile) (PAN). The membrane displays virtually quantitative retention of the polymeric catalyst; furthermore palladium could not be found in the permeate; TXRF and spectrophotometric determinations are indicative of >99.95% retention of the catalyst. The activity of the catalyst retained in the retentate is almost unchanged, as shown by the high (typically >90%) and almost constant yields of the coupling reactions as well as by the constant turnover frequencies of the catalysts following the membrane separation experiments during up to nine cycles of Sonogashira and Suzuki reactions. For the Heck coupling the used polar aprotic solvents best suited for the catalytic reaction lead to rapid deterioration of the membranes tested.

The objective of this study was to characterize variation and interrelatedness among primary functional and compositional parameters of commercially available sweet whey powders. Samples representing different plants/processes and cheese types were assayed for foaming capacity, foam stability, pH, protein content, soluble protein, turbidity, color, particle size distribution, lipid, and moisture. Data were analyzed using principal component analysis. Foaming capacity and stability varied from 10 to 220% and 0.1 to 14 min, respectively. Protein content and solubility ranged from 8.5 to 17.6% and 3.7 to 14.1%, respectively. Lipid content of sweet whey powder varied from 0.03 to 2.00%. The two main functional properties, foaming and protein solubility, did not show significant correlation with each other. Foaming properties showed a positive correlation to particle size and L* or lightness value, and negative correlation to lipid content. Protein solubility showed positive correlation with protein content and negative correlation with turbidity of the sample. Foaming behavior, protein, and particle size attributes were the main variables responsible for grouping of samples. Sweet whey powders from the same dairy plants were grouped together. The direct or indirect significance of these relationships to processing is detailed in this study.