Patents by Inventor Gauri Sankar Lal

Gauri Sankar Lal 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: 11891476
    Abstract: The present invention relates to a new structural class of phenalkamine, phenalkamine curing agent compositions, methods of making such phenalkamine, and methods of making such compositions. The phenalkamine curing agent compositions of the present invention can be prepared by reacting cardanol with an aldehyde compound and a mixture of methylene bridged poly(cycloaliphatic-aromatic)amines. These curing-agent compositions may be used to cure, harden, and/or crosslink an epoxy resin.
    Type: Grant
    Filed: October 22, 2020
    Date of Patent: February 6, 2024
    Assignee: Evonik Operations GmbH
    Inventors: Gauri Sankar Lal, Michael Cook
  • Patent number: 11603429
    Abstract: The present invention relates to a new structural class of phenalkamines, curing agent compositions comprising the phenalkamines, their use, as well as and methods of producing such phenalkamines and compositions. The phenalkamines of the present invention can be prepared by reacting cardanol with an aldehyde compound and triaminononane. These curing-agent compositions may be used to cure, harden, and/or crosslink an epoxy resin. The curing-agent compositions of this invention are of low viscosity and can be used neat or dissolved in a minimum amount of an organic solvent or diluent to effect cure of epoxy resins.
    Type: Grant
    Filed: March 29, 2019
    Date of Patent: March 14, 2023
    Assignee: Evonik Operations GmbH
    Inventors: Gauri Sankar Lal, Michael Cook, Gamini Ananda Vedage, Emmanouil Roumpelakis
  • Patent number: 11530293
    Abstract: Polyamide and amidoamine curing agents comprising a selectively modified amine. The selectively modified amine is formed by a substitution reaction between a polyamine and an epoxide, resulting in a multifunctional amine having a hydroxyl substituent. The curing agents are used to form epoxy resins having improved properties when cured.
    Type: Grant
    Filed: December 15, 2017
    Date of Patent: December 20, 2022
    Assignee: Evonik Operations GmbH
    Inventors: Gauri Sankar Lal, Sudhir Ananthachar, Stephen Michael Boyce
  • Patent number: 11365313
    Abstract: The present invention relates to a PVC plastisol composition comprising at least one vinyl chloride polymer selected from polyvinylchlorides and copolymers of vinyl chloride with one or more monomers; at least one plasticizer; at least one epoxy resin; and at least one isocyanate resin blocked with cardanol. The PVC plastisol composition of this invention provides strong adhesion to the surface of various metals or various undercoats of metals by thermal treatment for a short time at 100° C.-200° C. and is excellent in storage stability. In addition, it offers good rheological properties with improved yield value dosing and viscosity stability during applications compared to the nonylphenol blocked isocyanate PVC adhesion promotor.
    Type: Grant
    Filed: March 6, 2019
    Date of Patent: June 21, 2022
    Assignee: Evonik Operations GmbH
    Inventors: Gauri Sankar Lal, Pritesh G. Patel, Stephen Michael Boyce
  • Patent number: 11286336
    Abstract: A curing agent composition comprising anhydride and approximately equimolar amount of tertiary amine or imidazole and carboxylic acid, the amine being 1-piperidinylethanol (N-hydroxyethyl-piperidine, NHEP) represented by the structure below or an imidazole represented by the structure below: where R1=H, a C1-C20 straight chain or branched alkyl, or a monocyclic aryl; R2=a C1-C20 straight chain or branched alkyl, or a monocyclic aryl. The carboxylic acid is represented by RCOOH; R=a C1-C20 straight chain or branched alkyl, or a monocyclic aryl. The composition comprises a lower ratio of epoxy resin to anhydride (1:0.4-0.6) than typically used (1:0.8-1.1). In addition, it uses a higher loading of the hindered latent tertiary amine or the imidazole in combination with the carboxylic acid (wt % ratio of combined amine and carboxylic acid to anhydride ˜10%). With this composition a full cure can be achieved in less than 2 hr at a significantly lower temperature (˜100° C.).
    Type: Grant
    Filed: December 12, 2017
    Date of Patent: March 29, 2022
    Assignee: Evonik Operations GmbH
    Inventors: Pritesh G. Patel, Gauri Sankar Lal, Douglas M. La Comare
  • Publication number: 20210355270
    Abstract: The present invention relates to a new structural class of phenalkamines, curing agent compositions comprising the phenalkamines, their use, as well as and methods of producing such phenalkamines and compositions. The phenalkamines of the present invention can be prepared by reacting cardanol with an aldehyde compound and triaminononane. These curing-agent compositions may be used to cure, harden, and/or crosslink an epoxy resin. The curing-agent compositions of this invention are of low viscosity and can be used neat or dissolved in a minimum amount of an organic solvent or diluent to effect cure of epoxy resins.
    Type: Application
    Filed: March 29, 2019
    Publication date: November 18, 2021
    Inventors: Gauri Sankar Lal, Michael Cook, Gamini Ananda Vedage, Emmanouil Roumpelakis
  • Publication number: 20210188762
    Abstract: The present invention relates to a new method of making phenalkamines, products produced by such method, and use of such products. The method provides for phenalkamines obtained by an amine exchange reaction of a cardanol derived Mannich base with a compound with at least one alkylene or aralkylene group and at least two amino groups. These products may be used to cure, harden, and/or crosslink an epoxy resin. The curing agent compositions of this invention are of low viscosity and can be used neat or dissolved in a minimum amount of an organic solvent or diluent to effect cure of epoxy resins.
    Type: Application
    Filed: April 9, 2019
    Publication date: June 24, 2021
    Inventors: Gauri Sankar Lal, Michael Cook, Emmanouil Roumpelakis, Gamini Ananda Vedage
  • Publication number: 20210147708
    Abstract: The present invention relates to a polyurea coating composition comprising (A) a polyisocyanate; (B) a polyaspartic ester; and (C) an aspartic ester. The polyaspartic ester (B) is represented by the structure below: where Z=a cycloalkyl, alkyl or aryl group, R1, R2=alkyl groups containing 1-10 carbon atoms; and n=2-4. The aspartic ester (C) is derived from a secondary heterocyclic amine in a 3-7 membered ring compound bearing at least one secondary amine functionality. This invention also relates to use of a polyurea coating composition comprising (A)-(C) for the preparation of a polyurea coating. This invention further relates to a process for preparing a polyaspartic/aspartic ester mixture in-situ by initially reacting an ester of fumaric acid or maleic acid with a polyamine and then reacting the unreacted ester of fumaric acid or maleic acid to completion with a secondary heterocyclic amine.
    Type: Application
    Filed: April 24, 2019
    Publication date: May 20, 2021
    Inventors: Gauri Sankar Lal, Shafiq Fazel, Stephen Michael Boyce
  • Publication number: 20210139642
    Abstract: The present invention relates to a new structural class of phenalkamine, phenalkamine curing agent compositions, methods of making such phenalkamine, and methods of making such compositions. The phenalkamine curing agent compositions of the present invention can be prepared by reacting cardanol with an aldehyde compound and a mixture of methylene bridged poly(cycloaliphatic-aromatic)amines. These curing-agent compositions may be used to cure, harden, and/or crosslink an epoxy resin.
    Type: Application
    Filed: October 22, 2020
    Publication date: May 13, 2021
    Inventors: Gauri Sankar Lal, Michael Cook
  • Publication number: 20210047461
    Abstract: The present invention relates to a new structural class of phenalkamines, curing agent compositions comprising the phenalkamines, their use, as well as and methods of producing such phenalkamines and compositions. The phenalkamines of the present invention can be prepared by reacting cardanol with an aldehyde compound and triaminononane. These curing-agent compositions may be used to cure, harden, and/or crosslink an epoxy resin. The curing-agent compositions of this invention are of low viscosity and can be used neat or dissolved in a minimum amount of an organic solvent or diluent to effect cure of epoxy resins.
    Type: Application
    Filed: March 29, 2019
    Publication date: February 18, 2021
    Inventors: Gauri Sankar Lal, Michael Cook, Gamini Ananda Vedage, Emmanouil Roumpelakis
  • Publication number: 20210040301
    Abstract: The present invention relates to a PVC plastisol composition comprising at least one vinyl chloride polymer selected from polyvinylchlorides and copolymers of vinyl chloride with one or more monomers; at least one plasticizer; at least one epoxy resin; and at least one isocyanate resin blocked with cardanol. The PVC plastisol composition of this invention provides strong adhesion to the surface of various metals or various undercoats of metals by thermal treatment for a short time at 100° C-200° C. and is excellent in storage stability. In addition, it offers good rheological properties with improved yield value dosing and viscosity stability during applications compared to the nonylphenol blocked isocyanate PVC adhesion promotor.
    Type: Application
    Filed: March 6, 2019
    Publication date: February 11, 2021
    Inventors: Gauri Sankar Lal, Pritesh G. Patel, Stephen Michael Boyce
  • Publication number: 20200308339
    Abstract: Polyamide and amidoamine curing agents comprising a selectively modified amine. The selectively modified amine is formed by a substitution reaction between a polyamine and an epoxide, resulting in a multifunctional amine having a hydroxyl substituent. The curing agents are used to form epoxy resins having improved properties when cured.
    Type: Application
    Filed: December 15, 2017
    Publication date: October 1, 2020
    Inventors: Gauri Sankar Lal, Sudhir Ananthachar, Stephen Michael Boyce
  • Patent number: 10738147
    Abstract: The present invention relates to an amine-based curing agent comprising at least 1% by weight of at least one tertiary amine and, optionally, primary and/or secondary amines. The tertiary amine is preferably an N-substituted piperidine tertiary amine and, more preferably, N-hydroxyethyl piperidine (NHEP). The present invention also relates to an epoxy resin composition formed using this amine-based curing agent and a method of making the epoxy resin composition. These tertiary amines enhance desirable properties of epoxy resin compositions without the negative impact on mechanical properties in the cured product normally seen with tertiary amine-based curing agents.
    Type: Grant
    Filed: August 7, 2017
    Date of Patent: August 11, 2020
    Assignee: Evonik Operations GmbH
    Inventors: Pritesh G. Patel, Gauri Sankar Lal, Douglas M. La Comare
  • Patent number: 10696777
    Abstract: A polyurethane composition comprising a mixture comprising at least two aldehyde scavengers, a polyurethane product, and a process for making polyurethane foam are disclosed. The mixture of scavenger compounds can reduce, if not eliminate, the emissions of aldehydes from polyurethane foams. The scavenger compounds comprise at least one member selected from the group consisting of: phenol or substituted phenol, a 1,3-dicarbonyl compound, a polyamine bearing a 1,3-propanediamino function, melamine, a 1,2-diaminocycloalkane, an ammonium salt, and aminosiloxane.
    Type: Grant
    Filed: June 15, 2016
    Date of Patent: June 30, 2020
    Assignee: Evonik Operations GmbH
    Inventors: Juan Jesus Burdeniuc, Gauri Sankar Lal, Jennifer Elizabeth Antoline Al-Rashid, Torsten Panitzsch
  • Patent number: 10683385
    Abstract: A polyurethane composition comprising an aldehyde scavenger, a polyurethane product, and a process for making polyurethane foam are disclosed. The scavenger compounds can reduce, if not eliminate, the emissions of aldehydes from polyurethane foams. The scavenger compounds comprise at least one member selected from the group consisting of: phenol or substituted phenol, a 1,3-dicarbonyl compound, a polyamine bearing a 1,3-propanediamino function, melamine, a 1,2-diaminocycloalkane, an ammonium salt; a compound containing the bisulfite anion, titanium dioxide and aminosiloxane.
    Type: Grant
    Filed: June 16, 2015
    Date of Patent: June 16, 2020
    Assignee: Evonik Operations GmbH
    Inventors: Sheng Su, Juan Jesus Burdeniuc, Gauri Sankar Lal, Jennifer Elizabeth Antoline Al-Rashid, Torsten Panitzsch
  • Publication number: 20200123312
    Abstract: Polyamide and amidoamine curing agents comprising a selectively modified amine. The selectively modified amine is formed by a substitution reaction between a polyamine and an epoxide, resulting in a multifunctional amine having a hydroxyl substituent. The curing agents are used to form epoxy resins having improved properties when cured.
    Type: Application
    Filed: December 15, 2017
    Publication date: April 23, 2020
    Applicant: Evonik Operations GmbH
    Inventors: Gauri Sankar LAL, Sudhir ANANTHACHAR, Stephen Michael BOYCE
  • Publication number: 20200087446
    Abstract: A curing agent composition comprising anhydride and approximately equimolar amount of tertiary amine or imidazole and carboxylic acid, the amine being 1-piperidinylethanol (N-hydroxyethyl-piperidine, NHEP) represented by the structure below or an imidazole represented by the structure below: where R1=H, a C1-C20 straight chain or branched alkyl, or a monocyclic aryl; R2=a C1-C20 straight chain or branched alkyl, or a monocyclic aryl. The carboxylic acid is represented by RCOOH; R=a C1-C20 straight chain or branched alkyl, or a monocyclic aryl. The composition comprises a lower ratio of epoxy resin to anhydride (1:0.4-0.6) than typically used (1:0.8-1.1). In addition, it uses a higher loading of the hindered latent tertiary amine or the imidazole in combination with the carboxylic acid (wt % ratio of combined amine and carboxylic acid to anhydride ˜10%). With this composition a full cure can be achieved in less than 2 hr at a significantly lower temperature (˜100° C.).
    Type: Application
    Filed: December 12, 2017
    Publication date: March 19, 2020
    Applicant: Evonik Degussa GmbH
    Inventors: Pritesh G. PATEL, Gauri Sankar LAL, Douglas M. LA COMARE
  • Publication number: 20190292308
    Abstract: A curing agent composition including at least one imidazole salt represented by the structure: where R, R?, is H, or alkyl (1-20 carbon atoms) preferably lower alkyl of 1-7 carbon atoms, haloalkyl (1-20 carbon atoms), aryl, hydroxyl alkyl (1-7 carbon atoms), ester group(s), substituted alkyl and X? is a carboxylate anion of 1-40 carbon atoms; and at least one anhydride curing agent. The disclosed imidazole salts when combined with the anhydride curing agent provide improved latency for epoxy systems while maintaining reactivity at elevated temperature. Epoxy compositions, cured epoxy products and methods for forming cured epoxy products are also disclosed.
    Type: Application
    Filed: August 14, 2017
    Publication date: September 26, 2019
    Inventors: Gauri Sankar LAL, Edze Jan TIJSMA, Marieke Theodora van GORKOM
  • Patent number: 10174154
    Abstract: An epoxy curing agent is disclosed that can be obtained by reacting at least one carboxylic acid with at least one polyamine. The disclosed curing agent can be obtained by preparing an amidoamine with about 0.15 to about 0.30 molar excess of carboxylic acid.
    Type: Grant
    Filed: November 4, 2015
    Date of Patent: January 8, 2019
    Assignee: Evonik Degussa GmbH
    Inventors: Gauri Sankar Lal, Sudhir Ananthachar, Stephen Michael Boyce
  • Patent number: 10081704
    Abstract: The disclosure relates to at least one partially reacted product of an isocyanate and an amine (e.g., a reaction product comprising at least one adducted compound). The reaction product comprises polyurea oligomers. The reaction product can be combined with at least one amine in order to formulate a curing agent for epoxy resins wherein the cured epoxy resin has enhanced fracture toughness. The at least partially reacted product does not increase the viscosity of the curing agent and is at least partially soluble in the amine component of the curing agent.
    Type: Grant
    Filed: March 22, 2016
    Date of Patent: September 25, 2018
    Assignee: Evonik Degussa GmbH
    Inventors: Pritesh G. Patel, Judith Dolores Espinoza Perez, Gauri Sankar Lal, Jared Denis Bender, Edze Jan Tijsma