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Fluoroalkyl end‐capped trimethoxyvinylsilane oligomers, trimethoxyvinylsilane–N,N‐dimethylacrylamide cooligomers, and trimethoxyvinylsilane–acryloylmorpholine cooligomers were polymerized with hydrolysis and condensation between tetraethoxysilane (TEOS) and trimethoxysilyl segments in oligomers to afford homogeneous fluoroalkyl end‐capped oligomers/silica gel polymer hybrids under mild conditions. Similarly, fluoroalkyl end‐capped N,N‐dimethylacrylamide oligomers and acryloylmorpholine oligomers reacted with TEOS under mild conditions to afford the fluorinated oligomers/silica gel polymer hybrids. The formation of these fluorinated oligomers/silica gel polymer hybrids is due to the homogeneous incorporation of fluoroalkyl end‐capped oligomers into the silica gel networks through the intermolecular hydrogen bonding interaction between the residual silanol groups in silica gels and amido groups of fluorinated oligomers. We have also succeeded in preparing new fluorinated polymer hybrids by the use of fluoroalkyl end‐capped N,N‐dimethylacrylamide co‐oligomer‐containing silsesquioxane segments. Thermal stability of a variety of fluoroalkyl end‐capped oligomers/silica gel polymer hybrids thus obtained was found to increase significantly compared to those of the parent fluoroalkyl end‐capped oligomers. In addition, in these fluorinated oligomers/silica gel polymer hybrids, their sol solutions are applicable to the surface modification of glass to exhibit not only a strong oleophobicity imparted by fluorine but also a good hydrophilicity on the glass surface. Therefore, these fluorinated oligomers/silica gel polymer hybrids are suggested to have high potential for new functional materials through their unique properties imparted by not only fluorine but also by the hybrid counterparts. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 169–177, 2005

The effects of diets containing protein, protein hydrolysate or an amino acid mixture on nitrogen metabolism of normal and severely protein-deficient rats and on rats after gastrectomy and hepatectomy were compared. In experiment 1, rats weighing about 80 g were fed one of three experimental diets containing casein, protein hydrolysate or an amino acid mixture for 28 d. In experiment 2, rats weighing about 270 g were fed a protein-free diet for 40 d, and then one of the above three experimental diets for 14 d. In experiment 3, rats weighing about 220 g were totally gastrectomized and fed one of the three experimental diets for 21 d. In experiment 4, rats weighing about 210 g had about 70% of the liver resected, and then were fed one of the three experimental diets for 15 d. In all four experiments, daily food intake, daily body weight gain, nitrogen balance, urinary nitrogen compounds, body composition and hematologic values were measured. In normal, protein-deficient and hepatectomized rats, most results were similar for the groups fed protein, protein hydrolysate or amino acid diets, except that urinary ammonia was higher in the group fed the amino acid diet than in the other two groups. For about 10 d after total gastrectomy, food intake and growth of the animals fed the protein diet were lower than in the other two groups.