Patents by Inventor Gideon Levin

Gideon Levin has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5679281
    Abstract: Gelled material compositions for use as adsorbents and ion exchangers. The composition including a specific extractant, an organic solvent and a halopolymer modified by substitution with a radical of a substance compatible with the specific extractant. Optionally the composition may be in form of beads.
    Type: Grant
    Filed: March 21, 1994
    Date of Patent: October 21, 1997
    Assignees: Yeda Research and Development Co. Ltd., The Weizmann Institute of Science
    Inventors: Gideon Levin, Lev Bromberg
  • Patent number: 5209931
    Abstract: Crosslinked plasticized or unplasticized PVC products having gradient crosslinking density, with a high crosslinking density on the outer surface and a low or none crosslinking density at the bulk of the product, are prepared by immersing the PVC product in a hot water solution of a crosslinking material and a phase transfer catalyst. The products obtained provide controlled release of substances occluded within the PVC matrix, thus preventing leakage of plasticizers, stabilizers and other additives, and permitting controlled slow release of substances like pesticides, fertilizers, drugs and the like, into the surrounding environment.
    Type: Grant
    Filed: September 19, 1991
    Date of Patent: May 11, 1993
    Assignee: Yeda Research and Development Co. Ltd.
    Inventor: Gideon Levin
  • Patent number: 4806393
    Abstract: To plasticized polyvinyl chloride (PVC) there is applied a layer of PVC modified by the introduction of functional groups which can be crosslinked, preferably under the influence of heat. Such crosslinking provides a thin coating which prevents leakage of plasticizer and additives from the plasticized PVC substrate when it is contacted with solvents. Preferred modification of the PVC is by means of thiocarbamate moieties replacing some of the chlorine in the PVC from which the surface layer is produced.
    Type: Grant
    Filed: March 25, 1987
    Date of Patent: February 21, 1989
    Assignee: Yeda Research and Development Company Limited
    Inventor: Gideon Levin
  • Patent number: 4735997
    Abstract: There are provided polymers containing amido-thiolate groups. These are produced by a nuceophilic substitution of polymers containing chlorine, and the resulting polymers have a pronounced hydrophylic character. There is also provided a process for the production of these starting with polymers which contain chlorine in the polymeric backbone or in side chains.
    Type: Grant
    Filed: November 7, 1985
    Date of Patent: April 5, 1988
    Assignee: Yeda Research & Development Company Limited
    Inventors: Gideon Levin, Hemi N. Nae
  • Patent number: 4654391
    Abstract: There are provided polymers containing chlorine wherein part of the chlorine atoms are substituted by thio-amide groups and where a further part of the chlorine atoms are substituted by epoxy moieties. Starting materials of choice are chlorinated polyalkylenes, polyvinyl chloride and polyvinylidene chloride. The polymers are produced by first producing a chlorine containing polymer wherein part of the chlorine is substituted by thio-amide groups, and further reacting such product with an epoxy resin so as to introduce epoxy groups.
    Type: Grant
    Filed: November 26, 1985
    Date of Patent: March 31, 1987
    Assignee: Yeda Research and Development Co., Ltd.
    Inventors: Gideon Levin, Hemi N. Nae
  • Patent number: 4298714
    Abstract: The present invention relates to modified polyvinylchloride, wherein part of the chlorine atoms are replaced by groups of the formula --S--CH.sub.2 --CH.sub.2 --R--(CH.sub.2 --CH.sub.2 --R).sub.n --Alk, wherein R is selected from oxygen, sulfur and --NH--, where R may also designate a bond, where Alk designates an alkyl group of up to 14 carbon atoms, and where n is zero or an integer of from 1 to 100, and to a process for the production of such modified polyvinylchloride polymers which comprises reacting an aqueous emulsion or suspension of polyvinylchloride in the presence of a solvent adapted to cause swelling of the PVC particles with a compound of the formula Alk--(CH.sub.2 --CH.sub.2 --R).sub.n --R--CH.sub.2 --CH.sub.2 --SH, wherein Alk, R and n are as defined above.
    Type: Grant
    Filed: December 16, 1980
    Date of Patent: November 3, 1981
    Assignee: Yeda Research & Development Co. Ltd.
    Inventors: Gideon Levin, David Vofsi