Polymeric surface modifier

Most of the early published work on the separation of carotenoids by HPLC employs C18 stationary phases. It has been shown that polymeric surface modified Cl8 columns are more selective toward isomers compared to monomeiically bound columns (Figure 4.3) (Sander et ah, 1994). In the 1980s and 1990s, a 30 carbon bound stationary phase (C30 column) was developed and coined the carotenoid column, because of... 

Redispersible spherical BT nanoparticles with a narrow size distribution and a lower hydroxyl content were produced by our novel method, which we call the ambient condition sol (ACS) process, to produce pure crystalline nanometer-sized g-p 56-58 controlled particle size with a uniform distribution in the 50 to 100 nm size range from different refluxing media (e.g., water, butanol, toluene) was rapidly produced. During the process, a polymeric surface modifier can be added to protect the surface from agglomeration and to promote redispersibility after drying. The ACS process is similar to hydrothermal synthesis, but without applying pressure. 

Makal U, Wood L, Ohman DE, Wynne KJ. Polyurethane biocidal polymeric surface modifiers. Biomaterials 2006 27 1316-26. http //dx.doi.Org/10.1016/j.biomaterials.2005.08.038. 

Makal U, Wood L, Ohman DE, et al. Polyurethane biocidal polymeric surface modifiers. 

Surface Modification. Plasma surface modification can include surface cleaning, surface activation, heat treatments, and plasma polymerization. Surface cleaning and surface activation are usually performed for enhanced joining of materials (see Metal SURFACE TREATMENTS). Plasma heat treatments are not, however, limited to high temperature equiUbrium plasmas on metals. Heat treatments of organic materials are also possible. Plasma polymerization crosses the boundaries between surface modification and materials production by producing materials often not available by any other method. In many cases these new materials can be appHed directly to a substrate, thus modifying the substrate in a novel way. 

Last years the polymeric surface - active substances began to use as modifiers of organic reagent properties. In our work the behavior of synthetic polymers (polysulphonilpiperidinilmethylenhydroxide (PSPMH), polyvinylpyrrolidone (PVP), polyamines - polyguanidine and metacide) and natural polymers (starch, gelatin) for various molecular masses are investigated. 

Cyanoacrylate adhesives cure by anionic polymerization. This reaction is catalyzed by weak bases (such as water), so the adhesives are generally stabilized by the inclusion of a weak acid in the formulation. While adhesion of cyanoacrylates to bare metals and many polymers is excellent, bonding to polyolefins requires a surface modifying primer. Solutions of chlorinated polyolefin oligomers, fran-sition metal complexes, and organic bases such as tertiary amines can greatly enhance cyanoacrylate adhesion to these surfaces [72]. The solvent is a critical component of these primers, as solvent swelling of the surface facilitates inter-... 

The dendritic growth of lithium was suppressed on a lithium electrode surface modified by an ultrathin solid polymer electrolyte prepared from 1,1—difluoro-ethane by plasma polymerization [114]. 

Core-shell nanocomposite of Mg(OH)2/PMMA with an average particle size of ca. 500nm where Mg(OH)2 is the core and PMMA is the shell was successfidly prepared by the emulsion polymerization of MMA in the presence of surface modified Mj OH)2. The grapelike ( re-shell microspheres with PMMA nodules could he obtained as stable latex. 

To solve this problem, modern pesticide formulations use a variety of additives (adjuvants) to improve the mass efficiency. Surfactants and polymeric rheology modifiers are used to reduce spray drift, surfactants are used to modify surface tension and reduce... 

Membranes UF membranes consist primarily of polymeric structures (polyethersulfone, regenerated cellulose, polysulfone, polyamide, polyacrylonitrile, or various fluoropolymers) formed by immersion casting on a web or as a composite on a MF membrane. Hydrophobic polymers are surface-modified to render them hydrophilic and thereby reduce fouling, reduce product losses, and increase flux [Cabasso in Vltrafiltration Membranes and Applications, Cooper (ed.). Plenum Press, New York, 1980]. Some inorganic UF membranes (alumina, glass, zirconia) are available but only find use in corrosive applications due to their high cost. 

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. 

Surface modified NO sensors incorporate an electrode surface that has been modified or treated in some way so as to increase the selectivity of the sensor for NO and promote catalytic oxidation of NO. An early example of such a sensor was presented by Malinski and Taha in 1992 [27], In this publication an —500nm diameter carbon fiber electrode was coated with tetrakis(3-methoxy-4-hydroxyphenyl)porphyrin, via oxidative polymerization, and Nation. This electrode was shown to have a detection limit of — lOnM for NO and great selectivity against common interferences. However, recently it has been shown that this electrode suffers severe interference from H202 [28],... 

An alternative strategy to obtain silica immobilised catalysts, pioneered by Panster [23], is via the polycondensation or co-condensation of ligand functionalised alkoxysilanes. This co-condensation, later also referred to as the sol-gel process [24], appeared to be a very mild technique to immobilise catalysts and is also used for enzyme immobilisation. Several novel functional polymeric materials have been reported that enable transition metal complexation. 3-Chloropropyltrialkoxysilanes were converted into functionalised propyltrialkoxysilanes such as diphenylphosphine propyltrialkoxysilane. These compounds can be used to prepare surface modified inorganic materials. Two different routes towards these functional polymers can be envisioned (Figure 3.4). One can first prepare the metal complex and then proceed with the co-condensation reaction (route I), or one can prepare the metal complex after the... 

The synthetic route for making the Janus nanoparticles first consists in the emulsion polymerization of styrene in the presence of silica nanoparticles surface-modified by polymerizable groups. Snowman-like hybrid nanostructures are thus obtained with 85% yield in which the... 

Covalent functionalization of fullerenes has also been used to obtain surface-modified fullerenes that are more compatible to polymer matrices in order to fabricate composites. In this context, four basic strategies were developed. The first one allows the fullerenes to react during the monomer polymerization, so that the fullerene can be attached to the polymer chain [111, 112]. Second, an already synthesized polymer is treated using specific conditions that allow the chemical reaction with fullerenes [113,114]. Third, the fullerenes are chemically bonded to a monomer which is polymerized or co-polymerized to obtain the modified monomer [115,116]. Fourth, a dendrimer can be synthesized around a fullerene which then acts as a nucleus [117,118]. 

For the SEC analysis of polyelectrolytes, it is best to use a hydrophilic, polymeric packing or a surface-modified silica packing in which most of the silanols are derivatized. Another approach for the analysis of cationic polyelectrolytes is to use packings derivatized with cationic functional groups ( ). This is the basis of a commercially available SEC packing which is chemically bonded with polyethylenimine (W). 

Recently high purity styrene divinylbenzene polymeric gels have become available for use in lipophilic SPE extraction these types of materials formerly contained monomer materials which could interfere in analyses. These types of gels are much more lipophilic than surface-modified silica gels and also have a higher capacity for sample loading. Their applications are similar to those of the lipophilic silica gels. 

Similarly, gold particles were surface-modified with norborn-5-ene-2-ylmethanthiol and the surface-immobilized norborn-2-ene groups were subsequently used for norborn-2-ene polymerization in a grafting-from approach. The resulting material was used to construct a field effect transistor [32]. 

This leakage can also be reduced by chemical modification of the external surface of the bilayers in order to introduce polymeric components into the interfacial structure (see the section on surface modified liposomes). 

Dash, P.R., Read, M.L., Fisher, K.D., et al. (2000). Decreased binding to proteins and cells of polymeric gene delivery vectors surface modified with a multivalent hydrophilic polymer and retargeting through attachment of transferrin. J. Biol. Chem., 275, 3793-3802. 

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