AMINATED MATERIALS, GLASS

Vallo and Vazquez (20) used a heat transfer model to analyze the influence of process variables and material parameters (pulling velocity, wall temperature, fiber fraction) on the processing of an epoxy system (DGEBA-I-DGBD) cured by 3DCM amine with glass fiber. 

Other immobilization methods are based on chemical and physical binding to soHd supports, eg, polysaccharides, polymers, glass, and other chemically and physically stable materials, which are usually modified with functional groups such as amine, carboxy, epoxy, phenyl, or alkane to enable covalent coupling to amino acid side chains on the enzyme surface. These supports may be macroporous, with pore diameters in the range 30—300 nm, to facihtate accommodation of enzyme within a support particle. Ionic and nonionic adsorption to macroporous supports is a gentle, simple, and often efficient method. Use of powdered enzyme, or enzyme precipitated on inert supports, may be adequate for use in nonaqueous media. Entrapment in polysaccharide/polymer gels is used for both cells and isolated enzymes. 

Combinatorial approach to unsymmetrically tiered macromolecules [214] is a brand new area of research which would allow dendrimerization of materials (e. g., glass, classical polymers, fibers) and thus enable fine tuning of macromole-cular properties. For example, treatment of an amine terminated dendrimer with a mixture of complementary, isocyanate-based monomers [215, 216] affords a heterogeneous surfaced dendrimer. Selective transformation of the surface nitrile moieties via metal-catalyzed reduction to obtain a new polyamine dendrimer allows further combinatorial-based elaboration as illustrated in Fig. 42. 

The imine from benzaldehyde and benzyl amine (65 g, 0.33 mol) was added to phosphorous acid (27.3 g, 0.33 mol), and the mixture was stirred with heating. As the temperature reached 95 to 100°C, the entire mixture became a homogeneous liquid, which reacted vigorously as the temperature reached 115 to 120°C. After the reaction mixture became very viscous, it was allowed to cool, whereupon it condensed to a glass. The material was dissolved in aqueous sodium carbonate, which upon acidification precipitated pure N-benzyl a-aminobenzylphosphonic acid (90 g, 98%) of mp 233 to 234°C. The material exhibited analyses in accord with the proposed structure. 

De Mello et al. have constructed a so-called pSYNTAS (miniaturized synthesis and total analysis system). The system was used to perform an Ugi-type reaction to form several a-aminoacetamides from amines, isocyanates and formaldehyde in the presence of water (Scheme 25) [56-58]. The reported system consists of a glass/silicon nanoreactor [59] in connection to a TOF-MS for the real-time online analysis of the reaction stream. Reactions were conducted in the 600 nl volume chip under continuous flow of 20-2 pl/min flow rate. Reduced flow rates resulted in increased outputs. The analyzed outlet flow showed high yields of the desired products with small quantities of starting materials and intermediates (no exact yields were reported). 

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