Enhanced polymerization

NMP of S in heterogeneous media is discussed in reviews by Qiu et at.,205 Cunningham,206 207 and Schork et a/.208 There have been several theoretical studies dealing with NMP and other living radical procedures in emulsion and miniemulsion."09 213 Butte et nr/.210 214 concluded that NMP (and ATRP) should be subject to marked retardation as a consequence of the persistent radical effect. Charlcux209 predicted enhanced polymerization rates for minicmulsion with small... 

Taxol i is a naturally occurring substance isolated from the Pacific yew tree Taxus brevifolia), which has been approved for clinical treatment of cancer patients. Taxol enhances polymerization of tubuhn and the consequent formation of stable microtubules, inhibiting cellular mitosis. 

LMC is used in underwater concrete for both new construction and repair. The important requirements to obtain antiwashout capability, such as segregation resistance, flowability, self-leveling characteristics and lower bleeding are provided by the addition of viscosity-enhancing polymeric admixtures at polymer-cement ratios of 0.2-2.0%. These admixtures are water-soluble polymers, and classified under two groups, viz., cellulose types such as methyl cellulose and hydroxy ethyl cellulose and polyacrylamide types such as polyacrylamide and polyacrylamide-sodium acrylate [101]. 

S. Vilasagar, V. Lowry, D.M. Ferraris, K. Feng, R.E. Colbom, M.H. Littlejohn, and D.F. Townsend, Enhanced polymerization process, US Patent 6 784 253, assigned to General Electric Company (Pittsfield, MA), August 31, 2004. 

Increased production of free radicals making possible the induction of enhanced polymerization reactions and treatments... 

The intercalation of organic polymers into the interlayer space has also been widely studied since hybridization may not only produce unique materials with high dispersive ability, but may also enhance polymeric properties by nsing nanoscale reinforcements compared to the conventional particnlate-lilled... 

Boekelheide K. 1987. 2,5-Hexanedione alters microtubule assembly. II. Enhanced polymerization of crosslinked tubulin. Toxicol. Appl. Pharmacol. 88 383-96... 

MAPs generally inhibit depolymerization, and some enhance polymerization. Several MAPs can be phosphorylated on their projection domains by mitogen-activated protein kinase, or MAP kinase, which prevents them from binding microtubules. There is some evidence that MAPs can also be phosphorylated by Ca-CaMKII and that they may be directly influenced by Ca-CaM. Thus, MAPs may be modulated by signal pathways using Ca " " or MAP kinase, although specific roles for such control have not been clearly demonstrated. 

The odor is pungent, irritating (lachrymatory), acrid, resembling an extinguished stearin candle. Daylight enhances polymerization and formation of a plastic solid (Arctander, 1967). 

Microwave-assisted living cationic ring-opening showed an enhanced polymerization rate in comparison to the reaction in common organic solvents the ionic liquid was eSiciently recovered and reused in new reaction cycles, completely avoiding the use of volatile organic compounds [20]. 

The dose dependence of the light product yields in the PetroBeam process is similar to that observed for RTC. The maximal yield of stable light products is limited by the critical dose of electron irradiation when the rates of the competing reactions of radiation cracking and radiation-enhanced polymerization of hydrocarbons become comparable. The limiting dose becomes lower as the dose rate increases. However, increase in the dose rate allows greater production of light fractions at lower doses. 

Bo ngpoint. C 170 MettingpoInt. C -77 Fiash point, 50 Auto-lgnitiontemperature, C 490 Relative density (water 1) 0.9 Relativevepordensity(air 1) 4.1 Relative density at 20 C of saturated mixture vapor/air(air 1) 1.0 Vapor pressure, mm Hg at 20 C ca. 1.5 Solubility In water poor Explosive limits, vol% In air 0.8-11 Relative molecular mass 118.2 Grossformula COLORLESS LIQUID WITH CHARACTERISTIC ODOR Vapor mixes readily with air. Able to form peroxides and thus to polymerize. The presence of metallic salts enhances polymerization. Shong reducing agent which reacts violently with oxidants. ... 

T4.3 Enhanced Polymerization in High-Pressure Carbon Dioxide J07... 

The value of the monomer partition coefBcient between the CO2 and the water phase indirectly determines the ratio between the effect of enhanced polymerization and the effect of extraction on the reduction of residual monomer. Depending on the process conditions, i.e. temperature, pressure, and the phase behavior of the system involved, this ratio between enhanced polymerization and extraction may vary for different latex systems. With respect to the PMMA latex, the high partition coefBcient m2 as shown in Section 14.4, causes extraction to be the predominant effect as compared to conversion of the monomer. Therefore, a preliminary process design has been developed based on C02-extraction. For this purpose, a mass transfer model has been set up to determine the rate-limiting step in the extraction process. In addition, a process flow diagram, including equipment sizing has been developed. Finally, an economic evaluation has been performed to study the viability of this technique for the removal of residual monomer from latex-products. 

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