Abstract:
An elastic fiber is provided that includes polyurethane and/or polyurethaneurea and an additive such as polystyrene, an acrylic polymer, polyvinylpyrrolidone, copolymers thereof, derivatives thereof, and combinations thereof. The elastic fiber is useful in laminate structures, such as disposable hygiene articles as wells as in knit, woven and nonwoven fabric constructions.
Abstract:
The invention relates to recycling steam at elevated temperature and/or pressure generated within a thermosiphon esterifier design comprising a riser baffle in the vapor separator. Advantageously, the thermosiphon esterifier design can provide steam that can be employed in various additional processes and can thus provide an overall energy savings in operating the thermosiphon esterifier. Methods of using the steam are also described.
Abstract:
Included is a stretchable fabric composite laminate, which includes two outer layers of fabric with a bonded inner layer of elastomeric fibers. The stretchable fabric composite laminate is attached to the garment fabric as an edgeband or strap or within an edgeband or strap to provide a more comfortable garment or greater fit range.
Abstract:
The invention provides an oxygen Andrussow process for production of hydrogen cyanide from a methane-containing feedstock such as natural gas in the presence of oxygen and ammonia over a platinum catalyst, wherein the production of byproduct organonitrile impurities, such as acrylonitrile, is reduced. Limiting the content of C 2 + hydrocarbons in the methane feedstock in the oxygen Andrussow process, in contrast to the air Andrussow process, has been found to reduce formation of organonitriles, such as acrylonitrile. The organonitrile impurities can require additional processing for removal, cause fouling of equipment, and can also contribute to hydrogen cyanide polymerization. Reduction of C 2 + hydrocarbon levels to less than 2 wt%, or 1 wt%, or less than 0.1 wt%, in the methane can provide an improved yield of higher purity HCN. Reduction of C 2 + hydrocarbon levels also solves the problem of polymer buildup in process equipment, reducing downtime required for cleaning when higher C 2 + hydrocarbon levels are present in the reaction feed.
Abstract:
A static mixer is disclosed for a hydrogen cyanide reaction process that thoroughly mixes the reactant gases to form a ternary gas mixture that has a coefficient of variation of less than 0.1 across the diameter of the catalyst bed. The static mixer comprises tabs that are inserted through non-continuous slots in the conduit and the tabs are secured to the external wall of the conduit.
Abstract:
Disclosed is a process for the separation of water from a liquid phase medium containing an aliphatic carboxylic acid using azeotropic distillation in the presence of an entrainer. The entrainer, water, and organics are subsequently separated, wherein the entrainer is recycled back to the azeotropic distillation column and organics recycled back to the oxidation reactor.
Abstract:
The present invention provides an improved process for preparing a narrow molecular weight distributed polytetramethylene ether glycol (PTMEG). The product polytetramethylene ether glycol has an increased number average molecular weight, a lowered polydispersity and a reduced molecular weight ratio when compared to the polytetramethylene ether glycol in the corresponding feedstock.