Abstract: A water-absorbent resin composition excelling in an absorption capacity under pressure, a first transition of initial absorption, and the small amount of rewet is provided. It comprises a water-absorbent resin obtained by aqueous solution polymerization and by reversed-phase suspension or reversed-phase emulsion polymerization and shows a CSF of not less than 20 g/g or an AAP of not less than 20 g/g or an SFC of not less than 10 (unit: 10?7×cm3×s×g?1). The gaps among resin particles owing to the difference in shape form optimum gap widths for the sake of capillarity. The resin composition consequently formed, therefore, manifests such excellent properties without the influences of a surfactant or an emulsifier.
Abstract: A process for recovering a polyester, preferably polyethylene terephthalate, from contaminated polyester waste containing non-polyester components, such as polyester blended with cotton or other fibers in fabric or fiber forms, polyester magnetic tapes, coated polyester films and engineering resins, by dissolving the polyester in molten dimethylterephthalate, methyl-p-toluate or dimethylisophthalate as solvent and separating the polyester solution from the non-polyester components. The polyester can subsequently be recovered by crystallization or the polyester solution can be used as a feedstock for methanolysis to form dimethylterephthalate (DMT) and alkylene glycol. The DMT can be subsequently hydrolyzed to recover terephthalic acid (TPA).
Type:
Grant
Filed:
April 18, 1997
Date of Patent:
February 2, 1999
Assignee:
E. I. du Pont de Nemours and Company
Inventors:
William Duke Everhart, Kamel Michel Makar, Roger George Rudolph
Abstract: A process for manufacture of articles comprised of polyethylene terephthalate wherein the PET is colored with a composition comprised of a wax dispersant, ethylene copolymer, and a colorant. In a preferred embodiment, the wax dispersant is a maleated polyethylene wax. In an alternative embodiment, the wax dispersant is a low molecular weight polyethylene wax and the composition further includes linear low density polyethylene. A preferred ethylene copolymer is ethylene-(meth)acrylic acid.
Type:
Grant
Filed:
November 13, 1995
Date of Patent:
November 11, 1997
Assignee:
The M.A. Hanna Company
Inventors:
Tracy L. Phillips, Ronald M. Harris, Alan R. Burgess, Judy A. Johnston