Poly brushes films

An alternative photo-SIP approach was described by Kang and coworkers, where they used an argon plasma to oxidize alkylthiolate SAMs on planar gold [55]. The plasma treatment oxidized carboxy-terminated SAMs to peroxide moieties. UV irradiation in the presence of acryhc acid and allylpentafluorobenzene yielded ultra-thin graft layers of 6-7nm. The poly(acrylic acid) layers were found to adsorb Fe " ions from solution. This particular photoinitiation method yields low-density polymer brush films. 

Yu WH, Kang ET, Neoh KG. Controlled grafting of comb copolymer brushes on poly-(tetrafluoroethylene) films by surface-initiated living radical polymerizations. Langmuir 2005 21(l) 450-6. 

Surface-grafted, brushlike polymers can dramatically modify the lubricious properties of surfaces. The ability to bind a significant amount of solvent in a surface layer is thought to be one of the key mechanisms for low-friction, polymer-brush films. A brush composed of water-soluble, biocompatible polymers, such as poly(ethylene glycol), in an aqueous environment can provide an oil-free, environmentally friendly, food-compatible lubricious surface. 

Initial adhesion tests were made with 3.5- X 1- X 0.064-inch specimens of aluminum (Aluminum Associates No. 2024) and cold-rolled steel (polished ASTM A-415). Later tests were made with strips of copper, chrome-coated steel (Weirton Steel Co.), and brass with molded nylon 66 bars and with Mylar 300A poly (ethylene terephthalate) film. Before use, the specimens were washed (scrubbed with a soft bristle brush) with a solution of Alconox detergent, rinsed with water, rinsed with acetone, and dried. 

The polymer pair PVPON and PMAA was later used by Sukhishvih and coworkers to prepare hydrogen-bonded multilayer capsules and to discuss the effect of the substrate charge on the first adsorbed layer of the weak poly(carboxyhc acid) and the subsequent film growth [257]. Chen and coworkers used the same concept to prepare composite thin films by a hydrogen bonding assembly of polymer brushes and PVPON [258]. Spherical poly-... 

If consolidation is required only for surface layers of an object, application by brushing may be suflScient. Consolidant may be applied in several coats, but eventually a saturation of surface layers will lead to formation of undesirable glossy films. More resin can be introduced by application of many coats of low-concentration solutions than by use of solutions in high concentration, because the latter lead to early gloss formation (9). Barclay (7), for example, used a 5% solution of poly(vinyl butyral) resin (Butvar B90) in ethanol for brush treatment of parts of an English fire engine. 

A similar approach was adapted to prepare poly(methacrylic acid) (PMAA) brushes on silicon using TEM grids as masks. 2-Bromo-2-dimethyl-A-[3-(trimethoxysilyl)propyl]propanamide was employed as initiator. Patterned PMAA brushes with a resolution in the range of 100 pm were obtained, which were then used for templating the formation of microstructured calcite films (Figure 3.3) [2]. 

Huck et al. prepared Au NPs inside IL-based polyelectrolytes [70], The nanocomposite synthesis relies on loading the macromolecular film with AuCl precursor ions followed by their in situ reduction to Au nanoparticles. It was observed that the nanoparticles are uniform in size and are fully stabilized by the surrounding polyelectrolyte chains. Moreover, XRR analysis revealed that the Au NPs are formed within the polymer-brush layer. Interestingly, AFM experiments confirmed that the swelling behavior of the brush layer is not perturbed by the presence of the loaded NPs (Fig. 4.22]. The Au NP-poly-METAC nanocomposite is remarkably stable to aqueous environments, suggesting the feasibility of using this kind of nanocomposite systems as robust and reliable stimuli-responsive platforms. 

CAS 24936-74-1 26098-55-5 Synonyms Nylon 6/12 PA 612 Polyamide 612 Poly (hexamethylenedodecanediamide) Classification Thermoplastic polyamide Formula [NH(CH2)6NHCO(CH2)ioCO]n Properties Solid dens. 1.07 kg/l m.p. 210 C tens, str. ( yield) 60 MPa Uses Thermoplastic resin for molding, extrusion, films, brush bristles, industrial monofilament, cable/wire jacketing, elec./automotive parts food pkg. 

Free-radically produced poly(styrene) is atactic, having a glass transition temperature of 100°C. It is used mainly for injection-molded articles, e.g., household containers (flow temperature 140-160°C). A small quantity is used for highly oriented monofilaments for brush bristles and highly oriented films for insulation purposes. 

Many workers have examined the effect of surfactants and polymers adsorbed on mica. For example, polymers such as poly(vinyl pyridine) and its copolymers have been adsorbed on mica and their interfacial interactions measured in liquid media. Forces measured between these surfaces are of much longer range and provided some evidence for the brush conformation of polymers. Other workers have used industrially generated polymer films mounted directly to the glass lenses in the SFA and examined their adhesion... 

In this work, we wiU discuss the characteristic size-exclusion effect and excellent protein repeUency of concentrated brushes on the basis of our experimental data previously reported with poly(2-hydroxyethyl methacrylate) (PHEMA) brushes. PHEMA is a hydrophilic, biocompatible polymer, but the biocompatibility of PHEMA cast film is reported to be not as good as e.g., poly(2-methacryloxyethyl-phosphorylcholine) and poly(2-metho-xyethylacrylate) cast films. Hence any favorable results on the PHEMA brushes could be ascribed more to the structural,... 

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