Poly current research

Macromolecular Substitution Route. The current surge in poly-phosphazene research Is mainly a result of the development in the mid 1960 s (2-4) of a substitutive route to the synthesis of organo phosphazene high polymers. Before that time, only a sporadic interest in the subject existed because the known polymers, cross linked poly(dihalophosphazenes), (1,5) were insoluble and hydrolytically unstable. 

The development of RuO as a aT-dihydroxylation catalyst is a relatively new and potentially important area. Until recently OsO has been the reagent of choice for this, but use of the cheaper RuO may well become competitive, though stringent reaction conditions need to be used because RuO is so much more powerful an oxidant than OsO. Reactions are much faster than for OsO, but so-called flash dihydroxylations in which low temperatures are used have been developed, and are the subject of much current research. There are several reviews including mechanistic aspects [7-9] and one on the synthesis of poly oxygenated steroids [6]. The scope and limitations of the procedure have been discussed [155, 156]. 

The mechanical stability of polymers was related to the polymer s conformation in some of the earlier drag-reduction studies. Above a critical stress, degradation was faster the more contracted and entangled the polymer s conformation (5-7). In petroleum applications the mechanical instability of synthetic relative to carbohydrate polymers was well-recognized. The relative stability problems (possibly related to DUEVs (8)) encountered in the use of high molecular weight hydrolyzed poly(acrylamide) (HPAM) led to the development of an inverse-emulsion polymerization technique (9). (Current research directions using this technique are discussed in Chapter 9.)... 

The above discussion makes clear that colloidal particles and polyelectrolytes cannot be separated by size during free solution electrophoresis. As a result, many electrophoretic size separations for chemistry and biology are performed in gels. The precision afforded by microfabrication has led to miniaturized version of these classic protocols, as well as a number of novel separation techniques that differ distinctly from the separation principles prevailing in gels [5]. In order to best understand the current research in microfluidic separations of colloids and poly electrolytes, in particular the important apphcations to protein and DNA separations, it is important to first understand the physics of gel electrophoresis. 

Poly (thiophene)s are of particular interest as electfochromic materials owing to their chemical stability, ease of synthesis and processability. For the most part, current research has been focused on composites, blends and copolymer formations of several conjugated polyheterocyclics, polythiophene and its derivatives, especially PEIX)T. In one example, poly(3,4-ethylenedioxythiophene) (PEDOT)/poly(2-acrylamido-2-methyl-l-propanesulfonate) (PAMPS) composite films were prepared by Sonmez et al. for alternative electrochromic applications [50]. Thin composite films comprised of PEDOT/PAMPS were reported to switch rapidly between oxidized and neufial states, in less than 0.4 s, with an initial optical contrast of 76% at A.max. 615 nm. Nanostructured blends of electrochromic polymers such as polypyrrole and poly(3,4-ethylenedioxythiophene) were developed via self-assembly by Inganas etal. for application as an electrochromic window [26]. Uniir etal. developed a graft-type electrochromic copolymer of polythiophene and polytetrahydrofuran for use in elecfiochromic devices [51]. Two EDOT-based copolymers, poly[(3,4-ethylenedioxythiophene)-aZ/-(2,5-dioctyloxyphenylene)] and poly[(3,4-ethylenedioxythiophene)-aft-(9,9 -dioctylfluorene)] were developed by Aubert et al. as other candidates for electrochromic device development [52],... 

Bonartseva, A. P., Myshkinal, V. L., Nikolaeva, D. A., Furinal, E. K., Makhinal, T. A., Livshits, V. A., Boskhomdzhiev, A. P., Ivanov, E. A., lor-danskii, A. L., and Bonartseva, G. A. (2007). Biosynthesis, biodegradation, and application of poly(3- hydroxy butyrate) and its copolymers natural polyesters produced by diazotrophic bacteria. Current Research and Educational Topics and Trends in Applied Microbiology A. Mendez-Vilas (Ed.), p.295. 

Toulouse in 2009 and 2010, respectively, working at the A. N. Nesmeyanov Institute of Organoelement Compounds (Professor Elena S. Shubina) and the Laboratoire de Chimie de Coordination, UPR CNRS 8241 (Professor Rinaldo Poli). He spent two and a half years (2010-2013) as a JSPS postdoctoral fellow in Professor Takao Ikariya s group at the Tokyo Institute of Technology. He is a technical staff member at the Los Alamos National Laboratory, Los Alamos, New Mexico, where he was Director s and then J. Robert Oppenheimer Distinguished Postdoctoral Fellow with Dr. John C. Gordon (2013-2016). His current research interests include organometallic chemistry, computational quantum chemistry, and practical molecular catalysis. 

Summary of current research papers on miscibility studies of polymer blends based on poly(lactide) (PLA). 

Chitin, a poly(saccharide) closely related to cellulose and shown in Figure 4, is being studied by many research groups for a wide variety of biomedical, agricultural and cosmetic applications. Chitin is found mainly in insect and crustacean shells. Most current research centers on the deacetylated chitin, which is called chitosan. Figure 5. Chitosan is now finding some new uses in the textile industry, waste water treatment and medicine.While neither material is likely to be made synthetically on a commercial scale, both polymers are derived from formerly useless... 

Naczk M, Amarowicz R, Sullivan A, Shahidi F. 1998. Current research developments on poly-phenolics of rapeseed/canola A review. Food Chemistry, 62(4) 489-502. 

In 1954 the surface fluorination of polyethylene sheets by using a soHd CO2 cooled heat sink was patented (44). Later patents covered the fluorination of PVC (45) and polyethylene bottles (46). Studies of surface fluorination of polymer films have been reported (47). The fluorination of polyethylene powder was described (48) as a fiery intense reaction, which was finally controlled by dilution with an inert gas at reduced pressures. Direct fluorination of polymers was achieved in 1970 (8,49). More recently, surface fluorinations of poly(vinyl fluoride), polycarbonates, polystyrene, and poly(methyl methacrylate), and the surface fluorination of containers have been described (50,51). Partially fluorinated poly(ethylene terephthalate) and polyamides such as nylon have excellent soil release properties as well as high wettabiUty (52,53). The most advanced direct fluorination technology in the area of single-compound synthesis and synthesis of high performance fluids is currently practiced by 3M Co. of St. Paul, Minnesota, and by Exfluor Research Corp. of Austin, Texas. 

Rather more complex compounds that are currently being researched are the bolaform electrolytes [2-4]. Bolaform electrolytes are organic compounds possessing two cationic or two anionic groups linked by a flexible hydrocarbon chain the terminal groups may be aliphatic or aromatic (e.g. as in 10.1). Their interaction with sulphonated monoazo dyes in the presence of poly(vinylpyrrolidone) as substrate has been studied in detail. However, it remains to be seen what commercial developments take place with these interesting... 

Simon et al. [92] investigated a biocatalytic anode based on lactate oxidation by lactate dehydrogenase (LDH). The anodic current is generated by the oxidation of NADH (produced by NAD+ and substrate) while LDH catalyzes the electro-oxidation of lactate into pyruvate. As previously mentioned, the oxidation of NADH at bare electrodes requires a large overpotential, so these authors used poly(aniline) films doped with polyanions to catalyze NADH oxidation. Subsequent research by this group focused on targeting mutants of LDH that are amenable to immobilization on the polyaniline surface [93],... 

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