Patents by Inventor Tu N. Pham

Tu N. Pham 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: 11649303
    Abstract: Methods of post-polymerization modification of a polymer are provided herein. The present methods comprise the step of reacting a polymer with at least one nucleophile in a nucleophilic substitution reaction performed without a solvent to produce a functionalized polymer. The nucleophile can be selected from the group consisting of thioacetate, phenoxide, alkoxide, carboxylate, thiolate, thiocarboxylate, dithiocarboxylate, thiourea, thiocarbamate, dithiocarbamate, xanthate, thiocyanate. Nucleophilic substitution reaction can be performed in the presence of a phase transfer catalyst. Nucleophilic substitution reaction can also be performed via a two-step in-situ reactive mixing process with the initial formation of the polymer-amine ionomer (polymer-NR3+Br) which catalyzes the subsequent nucleophilic substitution with a second nucleophile to form a bi-functional polymer.
    Type: Grant
    Filed: March 29, 2019
    Date of Patent: May 16, 2023
    Assignee: ExxonMobil Chemical Patents Inc.
    Inventors: Paul Tu Quang Nguyen, David J. Freas, Tu N. Pham, Yuan-Ju Chen, Edward J. Blok, Anthony J. Dias
  • Publication number: 20210017304
    Abstract: Methods of post-polymerization modification of a polymer are provided herein. The present methods comprise the step of reacting a polymer with at least one nucleophile in a nucleophilic substitution reaction performed without a solvent to produce a functionalized polymer. The nucleophile can be selected from the group consisting of thioacetate, phenoxide, alkoxide, carboxylate, thiolate, thiocarboxylate, dithiocarboxylate, thiourea, thiocarbamate, dithiocarbamate, xanthate, thiocyanate. Nucleophilic substitution reaction can be performed in the presence of a phase transfer catalyst. Nucleophilic substitution reaction can also be performed via a two-step in-situ reactive mixing process with the initial formation of the polymer-amine ionomer (polymer-NR3+Br) which catalyzes the subsequent nucleophilic substitution with a second nucleophile to form a bi-functional polymer.
    Type: Application
    Filed: March 29, 2019
    Publication date: January 21, 2021
    Inventors: Paul Tu Quang Nguyen, David J. Freas, Tu N. Pham, Yuan-Ju Chen, Edward J. Blok, Anthony J. Dias
  • Patent number: 10562829
    Abstract: A process is disclosed for polishing a relatively highly pure stream of aromatic material bound for use as a petrochemical feedstock wherein the stream includes olefins and especially concerning, diolefins. The process comprises hydrotreating the highly pure aromatic stream with an unsulfided cobalt molybdenum catalyst that has low saturating activity for the aromatic but is active for saturating olefins and diolefins.
    Type: Grant
    Filed: December 6, 2018
    Date of Patent: February 18, 2020
    Assignee: Phillips 66 Company
    Inventors: Tushar Choudhary, Tu N. Pham, Sundararajan Uppili