Substrate polymer

Chinn J A, Horbett T A, Ratner B D, Sohway M B, Hague Y and Hausohka S D 1989 Enhanoement of serum fibroneotin adsorption and the olonal plating of swiss mouse-3T3 fibroplast and MM14-mouse myoblast sells on polymer substrates modified by radiofrequenoy plasma deposition J. Colloid Interface Sol. 127 67-87... 

The distance between the disk surface facing the optics and the memory layer naturally has to be much smaller than in common optical disks, where the memory layer is deposited behind a 1.2-mm thick transparent glass or polymer substrate disk. 

Another disadvantage of A1 substrates is their higher weight compared to polymer substrates, and particularly the significantly higher production costs of the disks themselves. 

Reactive (unsaturated) epoxy resins (qv) are reaction products of multiple glycidyl ethers of phenoHc base polymer substrates with methacrylic, acryhc, or fumaric acids. Reactive (unsaturated) polyester resins are reaction products of glycols and diacids (aromatic, aUphatic, unsaturated) esterified with acryhc or methacrylic acids (see POLYESTERS,unsaturated). Reactive polyether resins are typically poly(ethylene glycol (600) dimethacrylate) or poly(ethylene glycol (400) diacrylate) (see PoLYETPiERs). 

Sihcone products dominate the pressure-sensitive adhesive release paper market, but other materials such as Quilon (E.I. du Pont de Nemours Co., Inc.), a Werner-type chromium complex, stearato chromic chloride [12768-56-8] are also used. Various base papers are used, including polyethylene-coated kraft as well as polymer substrates such as polyethylene or polyester film. Sihcone coatings that cross-link to form a film and also bond to the cellulose are used in various forms, such as solvent and solventless dispersions and emulsions. Technical requirements for the coated papers include good release, no contamination of the adhesive being protected, no blocking in roUs, good solvent holdout with respect to adhesives appHed from solvent, and good thermal and dimensional stabiUty (see Silicon COMPOUNDS, silicones). 

Entrapment of biochemically reactive molecules into conductive polymer substrates is being used to develop electrochemical biosensors (212). This has proven especially useful for the incorporation of enzymes that retain their specific chemical reactivity. Electropolymerization of pyrrole in an aqueous solution containing glucose oxidase (GO) leads to a polypyrrole in which the GO enzyme is co-deposited with the polymer. These polymer-entrapped GO electrodes have been used as glucose sensors. A direct relationship is seen between the electrode response and the glucose concentration in the solution which was analyzed with a typical measurement taking between 20 to 40 s. 

Friedrich et al. also used XPS to investigate the mechanisms responsible for adhesion between evaporated metal films and polymer substrates [28]. They suggested that the products formed at the metal/polymer interface were determined by redox reactions occurring between the metal and polymer. In particular, it was shown that carbonyl groups in polymers could react with chromium. Thus, a layer of chromium that was 0.4 nm in thickness decreased the carbonyl content on the surface of polyethylene terephthalate (PET) or polymethylmethacrylate (PMMA) by about 8% but decreased the carbonyl content on the surface of polycarbonate (PC) by 77%. The C(ls) and 0(ls) spectra of PC before and after evaporation of chromium onto the surface are shown in Fig. 22. Before evaporation of chromium, the C(ls) spectra consisted of two components near 284.6 eV that were assigned to carbon atoms in the benzene rings and in the methyl groups. Two additional... 

A unique but not yet widespread technique that may influence the interfacial bond quality relies on the localized variation in the polymer modulus normal to the polymer-substrate junction in the composite assembly, as illustrated schematically in Fig. 15 [41,52]. The transversal modulus variation may be accomplished by interposing a tertiary interphase between the substrate and... 

Electric discharge methods are known [31] to be very effective for nonactive polymer substrates such as polystyrene, polyethylene, polypropylene, etc. They are successfully used for cellulose-fiber modification to decrease the melt viscosity of cellulose-polyethylene composites [32] and to improve the mechanical properties of cellulose-polypropylene composites [28]. 

Kabanov etal.123 hydrolyzed 44 (PNPA) and 56 (NABA) in the presence of QPVP. They found that the hydrolysis rate decreased with increasing degree of quatemization in water. A bell-shaped dependence was observed for 56 (NABA) in alcohol-aqueous media (see Fig. 13). Recently, Cho and Morawetz discussed the hydrolyses of a polymer substrate by a pyridine-containing polymer124. ... 

The multifunctional initiators may be di- and tri-, azo- or peroxy-compounds of defined structure (c.g. 20256) or they may be polymeric azo- or peroxy-compounds where the radical generating functions may be present as side chains 57 or as part of the polymer backbone."58"261 Thus, amphiphilic block copolymers were synthesized using the polymeric initiator 21 formed from the reaction between an a,to-diol and AIBN (Scheme 7.22).26 Some further examples of multifunctional initiators were mentioned in Section 3.3.3.2. It is also possible to produce less well-defined multifunctional initiators containing peroxide functionality from a polymer substrate by autoxidalion or by ozonolysis.-0... 

Won, J., Inaba, T., Masuhara, H., Fujiwara, H., Sasaki, K, Miyawaki, S. and Sato, S. (1999) Photofhermal fixation of laser-trapped polymer microparticles on polymer substrates. Appl. Phys. Lett., 75, 1506-1508. 

In-house materials development is most prevalent in the microelectronics industry, even down to polymer substrates for circuit lithography. Here, companies such as AT T and IBM have established some of the most impressive polymer science laboratories in the world to design and develop polymer systems for their own microelectronic products. They recover their development costs from the margins on final products. 

Intumescent additives. React with the polymer substrate to produce a char layer which forms an effective barrier between heat source and oxygen and... 

Method (1) is a slow process which requires several minutes of UV-irradiation for grafting a surface layer of an acrylic monomer onto the polymer substrate. 

Method (2) is a fast and efficient process which requires only 5 to 10 sec. UV-irradiation for surface grafting of the polymer substrate. About 2/3 of the polymer formed is grafted (about 1/3 is homopolymer). 

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