Poly surface coatings

Acrylics. Acetone is converted via the intermediate acetone cyanohydrin to the monomer methyl methacrylate (MMA) [80-62-6]. The MMA is polymerized to poly(methyl methacrylate) (PMMA) to make the familiar clear acryUc sheet. PMMA is also used in mol ding and extmsion powders. Hydrolysis of acetone cyanohydrin gives methacrylic acid (MAA), a monomer which goes direcdy into acryUc latexes, carboxylated styrene—butadiene polymers, or ethylene—MAA ionomers. As part of the methacrylic stmcture, acetone is found in the following major end use products acryUc sheet mol ding resins, impact modifiers and processing aids, acryUc film, ABS and polyester resin modifiers, surface coatings, acryUc lacquers, emulsion polymers, petroleum chemicals, and various copolymers (see METHACRYLIC ACID AND DERIVATIVES METHACRYLIC POLYMERS). 

Alkenylsuccinic anhydrides made from several linear alpha olefins are used in paper sizing, detergents, and other uses. Sulfosuccinic acid esters serve as surface active agents. Alkyd resins (qv) are used as surface coatings. Chlorendric anhydride [115-27-5] is used as a flame resistant component (see Flame retardants). Tetrahydrophthalic acid [88-98-2] and hexahydrophthalic anhydride [85-42-7] have specialty resin appHcations. Gas barrier films made by grafting maleic anhydride to polypropylene [25085-53-4] film are used in food packaging (qv). Poly(maleic anhydride) [24937-72-2] is used as a scale preventer and corrosion inhibitor (see Corrosion and corrosion control). Maleic anhydride forms copolymers with ethylene glycol methyl vinyl ethers which are partially esterified for biomedical and pharmaceutical uses (189) (see Pharmaceuticals). 

Of the higher vinyl ester homopolymers only poly(vinyl propionate) is currently believed to be of commercial value, being marketed as Propiofan (BASF) for surface coating application where greater alkali resistance is possible than with the normal vinyl acetate based copolymers. 

Acryloid and Plexigum. These were soft gummy products of interest as surface coatings rather than as mouldable plastics materials. About 1930 R. Hill in England and W. Bauer in Germany independently prepared poly(methyl methacrylate) and found it to be a rigid, transparent polymer, potentially useful as an aircraft glazing material. ... 

The nuclear substituted methyl styrenes have been the subject of much study and of these poly(vinyl toluene) (i.e. polymers of m- and /7-methylstyrenes) has found use in surface coatings. The Vicat softening point of some nuclear substituted methyl styrenes in given in Table 16.8. 

A number of higher poly(vinyl ether)s, in particular the ethyl and butyl polymers, have found use as adhesives. When antioxidants are incorporated, pressure-sensitive adhesive tapes from poly(vinyl ethyl ether) are said to have twice the shelf life of similar tapes from natural rubber. Copolymers of vinyl isobutyl ether with methyl acrylate and ethyl acrylate (Acronal series) and with vinyl chloride have been commercially marketed. The first two products have been used as adhesives and impregnating agents for textile, paper and leather whilst the latter (Vinoflex MP 400) has found use in surface coatings. 

Phenolic resins are useful surface coating materials. Resols are useful for stoving lacquers for coating chemical plant, textile equipment, razor blades, brassware cuid food cans. Phenolic resins are used with poly(vinyl formal) as a flexible, tough and solvent-resistant wire enamel. Oil-soluble resins based on synthetic phenols form the basis of some gloss paints. 

Polyesters are eneountered in many forms. They are important as laminating resins, moulding compositions, fibres, films, surface coating resins, rubbers and plasticisers. The common factor in these widely different materials is that they all contain a number of ester linkages in the main chain. (There are also a number of polymers such as poly(vinyl acetate) which contain a number of ester groups in side chains but these are not generally considered within the term polyester resins.)... 

SM O Connor, SH Gehrke, S Patuto, GS Retzinger. Fibrinogen-dependent adherence of macrophages to surfaces coated with poly(ethylene oxide)/poly(propylene oxide) triblock copolymers. Ann NY Acad Sci 831 138-144, 1997. 

In thick samples, a boron oxide/boron carbide crust has been detected on the surface of the polymer. This inorganic surface layer has a shielding effect on the inner polymer layers, further enhancing the thermal stability of the material. Poly(m-carborane-siloxane)s have therefore been considered as surface coatings for organic materials, providing protection from erosion effects. 

Results for the challenge of coated glass with S. aureus are shown in Table 1. The time of chlorination was a function of the hydrophilicity of the surface coating the poly(vinyl acetate oxazolidinone) polymers required the least amount of exposure to free chlorine. All of the surface coatings were effective against S. aureus in brief contact times. The grafted poly(acrylonitrile oxazolidinone) sample was not tested until 30 days after chlorination, but it still provided a 6-log inactivation of S. aureus in less than 10 min of contact. 

The immobilisation by electrostatic interactions of longer, 26 bp ssDNA strands on hard, poly(lysine)-coated glass resulted in aggregates of 63 nm (Fig. 26) [163]. Finally, when DNA molecules of the same length (26 bp) were covalently immobilised on the surface of plasma-induced, NHS-... 

Methyl methacrylate is polymerized to poly(methyl methacrylate), which is used in cast and extruded sheet (32%), surface coatings (24%), molding powder and resins (15%), impact modifiers (13%), and emulsion polymers... 

One problem for the coated system is that the film is peeled off after prolonged irradiation. In order to have a more adhesive film, the surface of n-Si was modified with N-(3-trimethoxysilyIpropyl)pyrrole (22). Pyrrole was then electrodeposited on this modified electrode as shown in Eq. (24) 85). The durability of the coated poly(pyrrole) was improved by such a treatment of n-Si surface. The n-Si electrode coated only with poly(pyrrole) gave a declined photocurrent from 6.5 to 1.8 mA cm-2 in less than 18 h, while the poly(pyrrole) coated n-Si treated at first with 22 as Eq. (24) gave a stable photocurrent of 7.6 mA cm-2 for 25 h. When an n-Si electrode was coated with Pt layer before the deposition of poly(pyrrole), the stability of the semiconductor was improved remarkably (ca. 19 days)85b). A power conversion efficiency of 5.5% was obtained with iodide/iodine redox electrolytes. 

Even when plastics are not a preferred material for the structural element of paneling, they are often incorporated as a surface coating or sheet to enhance aesthetics. Some lay-in ceiling panels for commercial and institutional applications consist of gypsum board covered with a poly(vinyl chloride) surface sheet to add a textured appearance. Many more are based on gypsum board or mineral wall with a fiber glass or PVC surface. 

Thus, a poly isobutylene coating on silver halide optical fiber was used for environmental analysis of chlorinated hydrocarbons in water in an instrument designed for operation in seawater 500 m under the surface (Fig. 9.27). The enrichment membrane concept can be used for FTIR-ATR analysis of liquid and gaseous samples alike. 

An inappropriate coating procedure for dsDNA may reduce the specificity of the test. Only ssDNA binds to the hydrophobic surfaces coated with polystyrol, the coating material generally used in ELISAs (E8). Cationic carriers for dsDNA binding, such as poly-L-lysine and protamine sulfate, may result in false-positive antibody reactions (B24). Another binder, an amphipolar ion-pair reagent, has been shown to be fully inert to immunoglobulins. 

Fig. 9. Force normalised by radius as a function of surface separation between mica surfaces coated with polyelectrolytes of various charge densities. The forces were measured across an aqueous 0.1 mM KBr solution. The polyelectrolytes were poly-MAPTAC ( ), AM-MAPTAC-30 ( ), AM-MAPTAC-10 ( ) and AM-MAPTAC-1 (o). Adapted with permission from Ref. [118]. 2002, American Chemical Society.

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