Patents by Inventor Walter S. Ropp

Walter S. Ropp 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).

  • Method of preparing hydroxyethyl ethers of cellulose
    Patent number: 4298728
    Abstract: In preparation of hydroxyethyl ethers of cellulose, ethylene oxide efficiency of the reaction and solubility characteristics of the product are improved by using alkali cellulose which has been prepared in the presence of boric acid or a boric acid salt.
    Type: Grant
    Filed: June 3, 1980
    Date of Patent: November 3, 1981
    Assignee: Hercules Incorporated
    Inventors: Thomas G. Majewicz, Walter S. Ropp
  • Process for producing spherical particles or crystalline polymers
    Patent number: 4254207
    Abstract: A process for producing uniformly small spherical particles of crystalline, normally solid condensation polymers is described. The process of this invention further provides high yields of hydrophobic, non-agglomerating particles in a useful size range directly, without the need for subsequent processing, and is carried out by forming a dispersion of small liquid particles of the crystalline polymer in certain aprotic liquids containing 0.1 to 20% by weight of the polymer of an acid-modified polymer of propylene in a specified manner, cooling the dispersion with agitation until the liquid particles solidify and recovering the particles.
    Type: Grant
    Filed: December 26, 1979
    Date of Patent: March 3, 1981
    Assignee: Hercules Incorporated
    Inventors: Leo M. Landoll, Walter S. Ropp