Anion polymer-based

In a different perspective, chitosan-anionic polymers-based extended-release tablets were developed and the feasibility of using this system for the sustained release of highly water-soluble drugs with high drug loading was tested. Here, sodium valproate and valproic acid combined were chosen as the model drugs. Anionic polymers such as... 

Y. Shao, L. li, X. Gu, L. Wang, and S. Mao, Evaluation of chitosan-anionic polymers based tablets for extended-release of highly water soluble drugs, Asian J. Pharm. Sci., 10,24-30,2015. 

In the area of municipal and iadustrial wastewater treatment, the principal environmental issue is the toxicity of residual flocculating agents ia the effluent. Laboratory studies have shown that cationic polymers are toxic to fish because of the iateraction of these polymers with giU. membranes. Nonionic and anionic polymers show no toxicity (82,83). Other studies have shown that ia natural systems the suspended inorganic matter and humic substances substantially reduce the toxicity of added cationic polymer, and the polymers have been used successfully ia fish hatcheries (84—86). Based on these results, the EPA has added a protocol for testing these polymers for toxicity toward fish ia the presence of humic acids (87). The addition of anionic polymers to effluent streams containing cationic polymers to reduce their toxicity has been mentioned ia the patent Hterature (83). 

The most effective and widely used dispersants are low molecular weight anionic polymers. Dispersion technology has advanced to the point at which polymers are designed for specific classes of foulants or for a broad spectmm of materials. Acrylate-based polymers are widely used as dispersants. They have advanced from simple homopolymers of acryflc acid to more advanced copolymers and terpolymers. The performance characteristics of the acrylate polymers are a function of their molecular weight and stmcture, along with the types of monomeric units incorporated into the polymer backbone. 

Caldero, G., Pi Subirana, R., Llosas Bigorra, J. and Torres Fernandez, M. (2001) Use of alkyl(ether) phosphates (I). European Patent EP 1264633. Sonneville-Aubrun, O. and Simonnet, J.-Th. (2001) Nanoemulsion based on anionic polymers, and uses thereof especially in the cosmetic, dermatological, pharmaceutical and/or ophthalmic fields. European Patent EP 1160005. 

The synthesis and characterization of a series of dendrigraft polymers based on polybutadiene segments was reported by Hempenius et al. [15], The synthesis begins with a linear-poly(butadiene) (PB) core obtained by the sec-butyllithium-initiated anionic polymerization of 1,3-butadiene in n-hexane, to give a microstructure containing approximately 6% 1,2-units (Scheme 3). The pendant vinyl moities are converted into electrophilic grafting sites by hydrosilylation with... 

The dodecahalogeno-closo-dodecaborates Bi2Xi22 can be oxidatively transformed into polyboranes BnXn. However, the anions proved not to be suitable for developing a chemistry of their own, e.g., polymers based on Bi2 units or dendrimers. Therefore, functional hydro-closo-dodecaborates carrying reactive substituents are needed. 

Below the outer membrane is a filter, usually composed of an anionic polymer, e.g. based on salicylate. Its precise composition and dimensions (thickness, pore size, amount and type of plasticizer, fillers, etc.) are optimized in order to tailor the diffusion rates of material crossing the filter from the analyte solution toward the working electrode of the sensor. Ideally, some uncharged molecules, such as H2O2, will traverse the filter so fast that, in effect, the filter is invisible to... 

Efforts were made to reduce the reactivity of Im toward Al. Other salts that could passivate A1 were used as additives with Lilm, and the results were encouraging.Also, structural modification of the imide anion was made by extending the perfluori-nated alkyl chain and was found to be effective, although at the price of lower ion conductivity. Although Lilm has never been used in any commercial lithium ion devices, it remains an interesting salt to be investigated, especially for the polymer-based electrolytes. ... 

Silicon is the most abundant metal-like element in the earth s crust. It is seldom present in pure elemental form, but is rather found in a large number of polymers based largely on the polycondensation of the orthosilicate anion, SiO as illustrated in the following equations ... 

Several different analytical and ultra-micropreparative CEC approaches have been described for such peptide separations. For example, open tubular (OT-CEC) methods have been used 290-294 with etched fused silicas to increase the surface area with diols or octadecyl chains then bonded to the surface.1 With such OT-CEC systems, the peptide-ligand interactions of, for example, angiotensin I-III increased with increasing hydrophobicity of the bonded phase on the capillary wall. Porous layer open tubular (PLOT) capillaries coated with anionic polymers 295 or poly(aspartic acid) 296 have also been employed 297 to separate basic peptides on the inner wall of fused silica capillaries of 20 pm i.d. When the same eluent conditions were employed, superior performance was observed for these PLOT capillaries compared to the corresponding capillary zone electrophoresis (HP-CZE) separation. Peptide mixtures can be analyzed 298-300 with OT-CEC systems based on octyl-bonded fused silica capillaries that have been coated with (3-aminopropyl)trimethoxysilane (APS), as well as with pressurized CEC (pCEC) packed with particles of similar surface chemistry, to decrease the electrostatic interactions between the solute and the surface, coupled to a mass spectrometer (MS). In the pressurized flow version of electrochromatography, a pLC pump is also employed (Figure 26) to facilitate liquid flow, reduce bubble formation, and to fine-tune the selectivity of the separation of the peptide mixture. 

Original Anionic Pathway to New PA(PO)a Star-Shaped Block Polymers Based on Polyvinyl or Polydiene Hydrocarbons and Polyoxirane... 

In the last few years the use of more rational synthetic methods based on living anionic polymers has become quite common. These polymers, usually of styrene or a-methylstyrene but sometimes of butadiene or styrene-butadiene mixtures, are initiated by metal alkyls and possess one reactive anionic end-... 

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