Vinyl palmitate

Fig. 18 77 -< A > Isotherms for PVP/PVAc binary monolayers on water at 25 °C. Surface pressure 77 for a variety of poly(vinyl palmitate)/poly(vinyl acetate) mixtures as defined in the plot are shown as a function of area per monomer. Surface concentration was controlled by step-wise compression. The incorporation of PVP, which does not form stable monolayers alone, condenses the film and also increases the instability of the film. < A > = average area per monomer...

Veratraldehyde, 31, 58 33, 65 Veratraldehyde, 6-nitro-, 33, 65 Veratrole, 36, 47 Veratrole, 4-iodo-, 36, 46 Vinyl acetate, 30, 106 Vinyl bromide, 39, 10 Vinyl capra te, 30,108 Vinyl caproate, 30,108 Vinyl caprylate, 30,108 Vinyl 10-hendecenoate, 30,108 Vinyl laurate, 30,106 Vinylmagnesium bromide, 39, 10 Vinyl myristate, 30,108 Vinyl oleate, 30,108 Vinyl palmitate, 30,108 Vinyl pelargonate, 30,108 Vinyl stearate, 30,108 2-Vinylthiophene, 38, 86 Vinyl undecylenate, 30,108... 

Vinyl myristate, 30,108 Vinyl oleate, 30,108 Vinyl palmitate, 30, 108 Vinyl pelargonate, 30,108 Vinyl stearate, 30, 108 2-Vinylthiophene, 38, 86 Vinyl undecylenate, 30,108... 

Similar to Figure 1, the palmitoyl (C-16) group has also been enzymatically grafted onto HEC. The reaction entails the incubation of HEC, vinyl palmitate, and a suitable enzyme in N,N-dimethylacetamide (DMAc) at 50°C. Several enzymes were attempted satisfactory results were obtained with Pseudomonas fluorescens lipase (Amano P-30), Pseudomonas capecia lipase (Lipase PS), or Alcalase immobilized alkaline protease from Novozymes A/S as a catalyst. Note that in this case a polar aprotic solvent (DMAc) is used, and one of the reactants, vinyl palmitate, has a fricile leaving group (vinyl alcohol which leaves as acetaldehyde). 

Fatty acid ester of hydroxyethylcellulose (HEC). A slurry containing 40% HEC, 40% vinyl palmitate, and 10% Pseudomonas fluorescens lipase (P-30, Amano) in N,N-dimethylacetamide was incubated at S0°C for 1-2 days. The resulting material was treated widi acetone followed by washing with isopropanol. The modified HEC was obtained as a white solid. The grafting of palmitoyl group was confirmed by IR analysis (1750 cm ). 

HEC ester HEC + vinyl palmitate CH3CH0 Lipase DMAc None High... 

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