Patents by Inventor Ajmir Khan

Ajmir Khan 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).

  • Publication number: 20240182665
    Abstract: The disclosure relates to a method for chemically recycling a condensation polymer, which includes melt-processing a mixture including a condensation polymer and an internal catalyst to increase the amorphous content of the polymer, followed by depolymerizing polymer in a reaction medium with a reactive solvent. Melt-processing and quenching of a condensation polymer generally reduces the crystalline content of the polymer and correspondingly increases the amorphous content of the polymer, which makes the polymer more amenable to subsequent depolymerization. Inclusion of the internal catalyst, for example a volatile organic catalyst, during melt-processing not only improves the relative degree of amorphization during melt-processing, but it also enhances the rate and conversion of the depolymerization stage that would otherwise be rate-limited by mass transport of an external catalyst from the bulk reaction medium to the polymer surface for depolymerization.
    Type: Application
    Filed: April 5, 2022
    Publication date: June 6, 2024
    Inventors: Muhammad Rabnawaz, Ajmir Khan, Zahra Aayanifard, Muhammad Naveed
  • Publication number: 20240084166
    Abstract: The disclosure relates to an omniphobic composition concentrate including 2 wt. % to 60 wt. % of at least one of a polyisocyanate and monomer units thereof in polymerized form, 30 wt. % to 85 wt. % of at least one of a polyol and monomer units thereof in polymerized form, 10 wt. % to 50 wt. % of at least one of a functionalized omniphobic polymer and monomer units thereof in polymerized form, and up to 60 wt. % of at least one diluent. The omniphobic composition further includes a polymer with monomer units of the polyisocyanate, monomer units of the polyol, and monomer units of the functionalized omniphobic polymer. The omniphobic composition is in the form of a gel-free liquid, and it can be cured with a polyol/polyisocyanate polyurethane base formulation to form a thermoset omniphobic composition.
    Type: Application
    Filed: September 12, 2023
    Publication date: March 14, 2024
    Inventors: Muhammad Rabnawaz, Ajmir Khan
  • Patent number: 11529648
    Abstract: The disclosure relates to a self-healing laminate composition. The composition includes a first, self-healing layer with a self-healing polymer and a second, mechanical layer adjacent to the first layer. The second layer includes any desired polymer, for example a crosslinked polymer, a thermoplastic polymer, or a functional thermoset polymer. Self-healing polymers with dynamic covalent bonds are suitable, for example those with dynamic urea bonds and/or dynamic urethane bonds. A self-healing polymer that is damaged can undergo autonomous repair when separated surfaces re-contact each other due to the soft nature of the self-healing polymer, whereupon reversible bonds can reform to rejoin and repair the damaged self-healing polymer. When the self-healing laminate according to the disclosure is damaged, the self-healing mechanism of the first layer can cause the repair of both layers.
    Type: Grant
    Filed: January 29, 2020
    Date of Patent: December 20, 2022
    Assignee: BOARD OF TRUSTEES OF MICHIGAN STATE UNIVERSITY
    Inventors: Muhammad Rabnawaz, Ajmir Khan
  • Patent number: 11396574
    Abstract: The disclosure relates to a self-healing omniphobic composition including a self-healing omniphobic polymer with a crosslinked backbone. The crosslinked backbone includes a reaction product between a polyisocyanate, a functionalized omniphobic polymer reactive therewith, a reversible polyfunctional linker including a hindered secondary amino group and/or an aromatic hydroxy group, and one or more polymeric backbone components. The crosslinked backbone includes reversible urea or reversible urethane bonds between the reversible polyfunctional linker and the polyisocyanate, which in turn provide self-healing properties to the omni-phobic composition. The self-healing omniphobic composition has favorable omniphobic properties, for example as characterized by water and/or oil contact and/or sliding angles. The omniphobic composition can be used as a coating on any of a variety of substrates to provide self-healing omniphobic properties to a surface of the substrate.
    Type: Grant
    Filed: January 2, 2020
    Date of Patent: July 26, 2022
    Assignee: BOARD OF TRUSTEES OF MICHIGAN STATE UNIVERSITY
    Inventors: Muhammad Rabnawaz, Ajmir Khan, Kun Huang
  • Publication number: 20220040730
    Abstract: The disclosure relates to a self-healing laminate composition. The composition includes a first, self-healing layer with a self-healing polymer and a second, mechanical layer adjacent to the first layer. The second layer includes any desired polymer, for example a crosslinked polymer, a thermoplastic polymer, or a functional thermoset polymer. Self-healing polymers with dynamic covalent bonds are suitable, for example those with dynamic urea bonds and/or dynamic urethane bonds. A self-healing polymer that is damaged can undergo autonomous repair when separated surfaces re-contact each other due to the soft nature of the self-healing polymer, whereupon reversible bonds can reform to rejoin and repair the damaged self-healing polymer. When the self-healing laminate according to the disclosure is damaged, the self-healing mechanism of the first layer can cause the repair of both layers.
    Type: Application
    Filed: January 29, 2020
    Publication date: February 10, 2022
    Inventors: Muhammad Rabnawaz, Ajmir Khan
  • Publication number: 20220041787
    Abstract: The disclosure relates to a self-healing omniphobic composition including a self-healing omniphobic polymer with a crosslinked backbone. The crosslinked backbone includes a reaction product between a polyisocyanate, a functionalized omniphobic polymer reactive therewith, a reversible polyfunctional linker including a hindered secondary amino group and/or an aromatic hydroxy group, and one or more polymeric backbone components. The crosslinked backbone includes reversible urea or reversible urethane bonds between the reversible polyfunctional linker and the polyisocyanate, which in turn provide self-healing properties to the omni-phobic composition. The self-healing omniphobic composition has favorable omniphobic properties, for example as characterized by water and/or oil contact and/or sliding angles. The omniphobic composition can be used as a coating on any of a variety of substrates to provide self-healing omniphobic properties to a surface of the substrate.
    Type: Application
    Filed: January 2, 2020
    Publication date: February 10, 2022
    Inventors: Muhammad Rabnawaz, Ajmir Khan, Kun Huang