Polymeric surface coatings

The conducting of polymerization reactions in a solvent is an effective way to disperse heat in addition, solutions are much easier to stir than bulk polymerizations. Solvents must be carefully chosen, however, so that they do not imdergo chain-transfer reactions with the polymer. Because it can be difficult to remove solvent from the finished viscous polymer, solution polymerization lends itself best to polymers that are used commercially in solution form, such as certain types of adhesives and surface coatings. Polymerization of gaseous monomers is also conducted with the use of solvents, as in the production of polyethylene. Refer to Bulk Polymerization and Suspension Polymerization. 

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). 

Various types of surface coating materials can be used with sohd fiber paperboard to achieve desired package properties. The coatings and treatments described for cormgated paperboard apply to sohd fiber paperboard as weU. Various solvent and aqueous-based polymeric emulsion coatings are also commonly used (see Emulsions). 

Addition of one mole of P,P -dipheny1methy1enediphosphinic acid to tetraisopropyl titanate gives a chelated product, the solutions of which can be used as a primer coat for metals to enhance the adhesion of topcoats, eg, alkyds, polyalkyl acylates, and other polymeric surface coating products, and improve the corrosion resistance of the metal to salt water (102). 

Chlorinated paraffins are versatile materials and are used in widely differing appHcations. As cost-effective plasticizers, they are employed in plastics particularly PVC, mbbers, surface coatings, adhesives, and sealants. Where required they impart the additional features of fire retardance, and chemical and water resistance. In conjunction with antimony trioxide, they constitute one of the most cost-effective fire-retardant systems for polymeric materials, textiles, surface coatings, and paper products. Chlorinated paraffins are also employed as components in fat Hquors used in the leather industry, as extreme pressure additives in metal-working lubricants, and as solvents in carbonless copying paper. 

In addition to plastics materials, many fibres, surface coatings and rubbers are also basically high polymers, whilst in nature itself there is an abundance of polymeric material. Proteins, cellulose, starch, lignin and natural rubber are high polymers. The detailed structures of these materials are complex and highly sophisticated in comparison the synthetic polymers produced by man are crude in the quality of their molecular architecture. 

Y. Camberlin, J. Grenier, S. Poncet, A. Bonnet, J. P. Pascault, and H. Sautereau. Utilization of polymer compositions for the coating of surfaces, and surface coating containing such compositions (utilisation de compositions de polymeres pour le revetement de surfaces et revete-ment de surfaces comprenant ces compositions). Patent EP 931819, 1999. 

A surface-modified polymeric system can be obtained by spin coating or heating [Ru(L6)3]21 as its / -tosylate salt.16 The resulting film shows seven-color electrochromism whose colors cover the spectral range, which can be scanned in 250 ms. 

Benters et al. (2002) of the University of Bremen in Germany utilized starburst dendrimers to create polymeric surface coatings for glass substrates in an effort to increase sensitivity for DNA microarrays (Figure 3.18). Ami-nosilane or epoxysilane chemistries were applied to glass substrates. The... 

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... 

Formation of peroxides by exposure to air and their involvement in polymerization processes is important for surface coating formulations containing polyunsaturated lipids called drying oils. Also nondrying oils, such as soybean oil, are under development as renewable sources for plastics and resins " . ... 

In the following section, a new technique of surface modification of fillers and curing agents will be discussed plasma polymerization. This technique allows for surface coating of powders, whereby the chemical structure of the coating is determined by the monomer used for the process. The morphology of the substrate is preserved, which is an important precondition for filler treatment. The polarity of the functional groups can be chosen to fit the matrix of the polymer wherein it will be applied. 

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