摘要:
Processes for the production of chlorinated alkanes are provided. The present processes comprise catalyzing the addition of at least two chlorine atoms to an alkane and/or alkene with a catalyst system comprising one or more nonmetallic iodides and/or lower than conventional levels of elemental iodine and at least one Lewis acid. The present processes make use of sulfuryl chloride, or chlorine gas, as a chlorinating agent.
摘要:
An ester of a sugar and a brominated fatty acid is a useful FR additive for combustible polymers. The brominated FR additives unexpectedly are stable at the extrusion temperatures, and provide excellent flame retardancy to the combustible polymers.
摘要:
The present invention provides one-step processes for the production of chlorinated and/or fluorinated propenes. The processes provide good product yield with low, e.g., less than about 20%, or even less than 10%, concentrations of residues/by-products. Advantageously, the processes may be conducted at low temperatures relative to conventional processes, so that energy savings are provided, and/or at higher pressures so that high throughputs may also be realized. The use of catalysts may provide enhancements to conversion rates and selectivity over those seen in conventional processes, as may adjustments to the molar ratio of the reactants.
摘要:
Extruded polymer foams are prepared using brominated fatty acids, an ester, amide or ester-amide of a brominated fatty acid, a glyceride of one or more brominated fatty acids, or a polymerized brominated fatty acid as an FR additive. The brominated FR additives unexpectedly are stable at the extrusion temperatures, and provide excellent flame retardancy to the foams.
摘要:
Group 4 metal complexes of the constrained geometry type, catalysts derived therefrom, and polymerization processes using the same, characterized by an alkaryl-substituted silane bridging group are disclosed.
摘要:
Dense star polymer conjugates which are composed of at least one dendrimer in association with at least one unit of a carried agricultural, pharmaceutical, or other material have been prepared. These conjugates have particularly advantageous properties due to the unique characteristics of the dendrimer.
摘要:
Halogenated, unsaturated alcohols are dehydrated by contacting the alcohol and a carrier gas with a silica alumina catalyst to form dienes of the formula: ##STR1## wherein each X is independently hydrogen, fluorine chlorine, or bromine with the proviso that no more than one of them is hydrogen, and each R is independently hydrogen, alkyl, aralkyl, alkaryl, or aryl.
摘要:
Processes for the production of chlorinated alkanes are provided. The present processes comprise reacting one or more mono- and/or dichloroalkanes to form tri-, tetra- and/or pentachloroalkanes, with high regioselectivity. In those embodiments wherein a dichloroalkane is desirably utilized, it may advantageously be a vicinal dichloroalkane. Further, only one catalyst is utilized. The present processes make use of sulfuryl chloride as a chlorinating agent, rather than a gaseous chlorinating agent such as chlorine gas. Finally, the process uses lower intensity process conditions than at least some conventional processes, and thus, operating costs are saved.
摘要:
Processes for the production of chlorinated and/or fluonnated propenes provide good product yield with advantageous impurity profiles in the crude product. Advantageously, the processes may be conducted at lower temperatures than 600° C., or less than 500° C., so that energy savings are provided, and/or at higher pressures so that high throughputs may also be realized. The use of catalysts or initiators may provide additional enhancements to conversion rates and selectivity, as may adjustments to the molar ratio of the reactants.
摘要:
Processes for the production of chlorinated propenes are provided. The present processes make use of a feedstream comprising 1,2-dichloropropane, a by-product in the production of chlorohydrin, as a low cost starting material, alone or in combination with 1,2,3-trichloropropane. Selectivity of the process is enhanced over conventional processes employing successive chlorinations and/or dehydrochlorinations, by conducting at least one chlorination in the presence of an ionic chlorination catalyst. The present processes may also generate anhydrous HCl as a byproduct that can be removed from the process and used as a feedstock for other processes, providing further time and cost savings.