Polymer-modified glasses

If the hydrolyses in silane precursor-polymer systems are carried out using relatively large amounts of the silane, then the silica generated can become the continuous phase, with the elastomeric polysiloxane dispersed in it.12 14 136-143 Again, a variety of ceramic components and polymeric components have been studied. The resultant composite is a polymer-modified glass or ceramic, frequently of very good transparency. Although its thermal stability will be inferior to that of the ceramic component itself, there are many applications for ceramic-type materials where this is not a serious problem. 

Source Bijen, J. and Van den Plas, C. (1992) Polymer Modified Glass fibre Reinforced Gypsum, London Chapman and Hall/Spon. 

Bijen, J., Van den Plas, C. (1992) Polymer modified glass fibre reinforced gypsum , in Proc. Int. Workshop on HPFRCC, H. W. Reinhardt and A. E. Naaman eds, RlLEM/ACl, Mainz, 23-26 June 1991, London Chapman and Hall/Spon, pp. 100-15. 

Polymer-Modified Glasses. If the hydrolyses in silane-polymer systems are carried out using relatively large amounts of silane, then the silica generated can become the continuous phase, with the elastomeric polysiloxane dispersed in it... 

A. Sugiura and M. Vtfekasuti, Durability and Fire Resistance of Polymer Modified Glass Fiber Reinforced Cement , in S. Nagataki, T. Nireki, and T. Tomosawa (eds) Durability of Building Materials and Components 6, Proc. Int. Conf. (Japan), E FN Spon, London, 1993, pp. 139-146. 

P. Soroushian, A. TIili, M. Yohena and B.L. Tilsen, Durability characteristics of polymer-modified glass fiber reinforced concrete . Ad materials Journal QQ, 40-49, 1993. 

In 1971, Hiatt et al. found that polyethylene oxide (PEO) of molecular weight about 100000 prevented the adsorption of rabies virus to porous glass with an average pore diameter of 1250 A. The support was modified by passage of one void volume of 0.4% solution of the polymer in water, followed by 5 or more volumes of distilled water or buffered salt solution. The virus was effectively purified from the admixtures of brain tissue fluid by means of size-exclusion chromatography on the modified glass column [28]. 

Chemical and electrochemical techniques have been applied for the dimensionally controlled fabrication of a wide variety of materials, such as metals, semiconductors, and conductive polymers, within glass, oxide, and polymer matrices (e.g., [135-137]). Topologically complex structures like zeolites have been used also as 3D matrices [138, 139]. Quantum dots/wires of metals and semiconductors can be grown electrochemically in matrices bound on an electrode surface or being modified electrodes themselves. In these processes, the chemical stability of the template in the working environment, its electronic properties, the uniformity and minimal diameter of the pores, and the pore density are critical factors. Typical templates used in electrochemical synthesis are as follows ... 

Wasson, E. A. Nicholson, J. W. (1990). A study of the relationship between setting chemistry and properties of modified glass-poly(alkenoate) cements. British Polymer Journal, 23, 179-83. 

In 1996, Gauglitz and coworkers coated surfaces with various amino-and carboxy-substituted polymers [198], The polymers tested were branched poly-(ethyleneimine), a,co-amino-functionalized PEG, chitosan, poly(acrylamide-co-acrylic acid) and an amino-modified dextran. The amino-substituted polymers were immobilized on glass by first immobilizing an aminosilane, followed by succinic anhydride/A-hydroxysuccinimide linker chemistry. Poly(acrylamide-co-acrylic acid) was directly coupled to an aminosilanized surface. When probed with 1 mg mL 1 ovalbumin solution, nonspecific adsorption was lowest for the dextran derivative. Notably, nonspecific adsorption increased in most cases when a hydrophobic hapten (atrazine) was coupled to the polymer-modified surface. 

Thin-film electrode — An electrode covered with a thin film of a given substance. The purpose of placing a thin film on the electrode surface is to obtain desired electrode properties. Many different substances have been used to prepare film electrodes they include among others mercury (see - thin mercury film electrodes) gold, boron-doped diamond (see - boron-doped diamond electrode), conductive polymers (see - polymer-modified electrode), and alkanethiols. The film thickness can vary from several micrometers (mercury) to monomolecular layers (thiols). In some cases (e.g., for - spectroelectrochemistry purposes) very thin layers of either gold or tin oxide are vapor-deposited onto glass plates. Thin film electrodes are often called - surface-modified electrodes. 

Naito and Kanemitsu (1996) investigated the relationship between the prefactor mobilities, zero-field mobilities, and the glass transition temperatures of OX doped polyarylate (PA), PC, poly(methyl methacrylate) (PMMA), PS, poly(vinyl chloride) (PVC), polyethylene terephthalate) (PET), and poly(vinyl butyral) (PVB), DEH doped PC, 5(p-diethylaminophenyl)-l-phenyl-3-(/ -diethylaminostyryl)-2-pyrazoline (DEASP) doped PS, and DEASP doped PC. OX, DEH, and DEASP are highly polar molecules with similar dipole moments. By modifying the polymer, the glass transition temperature can be varied over... 

Besides the classical polymer introduced by Merrifield (1%-crosslinked chloromethylated polystyrene), a broad variety of polymeric supports is available for SPPS and some of the most popular resins are summarized in Table 1. The chemical structures of some selected resins are presented in Figure 1 and electron micrographs of several examples are displayed in Figure 2. In addition to the solid supports listed in Table 1, there are several other carriers used in peptide synthesis such as the gel-type and macroporous poly(meth-acrylates), coated surfaces like polystyrene films on polyethylene (PEt) sheets, polystyrene-coated polyethylene or polytetrafluoroethylene, and modified glass surfaces. (For recent reviews on polymeric carriers see refs . )... 

A further illustration of IGC as a source of data for acid/base characterization of polymers and of solid constituents of complex polymer systems, is given by Osmont and Schreiber (49), who rate the inherent acid/base interaction potentials of glass fiber surfaces and of polymers by a comparative index, based on the Drago acid/base concepts (SO). The interaction index is conveniently measured by IGC and is shown to differentiate clearly among untreated and variously silane-modified glass fiber surfaces. Conventional methods are used to determine adsorption isotherms for fiber-polymer pairs, and the IGC data ate used to demonstrate the relationship between acid/base interactions and the quantity of polymer retained at fiber surfaces. 

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