Browsing by Author "Boul, Peter"

Now showing 1 - 13 of 13
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    Additive manufacture-assisted method for making structural elements having controlled failure characteristics
    (2023-08-15) Sajadi, Seyed Mohammad; Meiyazhagan, Ashokkumar; Boul, Peter; Rahman, Muhammad; Thaemlitz, Carl; Ajayan, Pulickel; Rice University; Saudi Arabian Oil Company; William Marsh Rice University; United States Patent and Trademark Office
    A process for making a layered multi-material structural element having controlled mechanical failure characteristics. The process includes the steps of: supplying a cementitious layer and forming a polymer layer on the cementitious layer by additive manufacture such that the polymer layer has a first thickness and the cementitious layer has a second thickness, wherein the polymer layer comprises a polymer and the cementitious layer comprises a cementitious material; and allowing the polymer from the polymer layer to suffuse into the cementitious layer for a period of time to obtain a suffused zone in the cementitious layer such that the suffused zone has a third thickness that is less than half the second thickness.
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    Additive manufacture-assisted method for making structural elements having controlled failure characteristics
    (2024-06-18) Sajadi, Seyed Mohammad; Meiyazhagan, Ashok Kumar; Boul, Peter; Rahman, Muhammad; Thaemlitz, Carl; Ajayan, Pulickel; Rice University; Saudi Arabian Oil Company; United States Patent and Trademark Office
    A process for making a layered multi-material structural element having controlled mechanical failure characteristics. The process includes the steps of: supplying a cementitious layer and forming a polymer layer on the cementitious layer by additive manufacture such that the polymer layer has a first thickness and the cementitious layer has a second thickness, wherein the polymer layer comprises a polymer and the cementitious layer comprises a cementitious material; and allowing the polymer from the polymer layer to suffuse into the cementitious layer for a period of time to obtain a suffused zone in the cementitious layer such that the suffused zone has a third thickness that is less than half the second thickness.
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    Additive manufacture-assisted method for making structural elements having controlled failure characteristics
    (2024-05-28) Sajadi, Seyed Mohammad; Meiyazhagan, Ashok Kumar; Boul, Peter; Rahman, Muhammad; Thaemlitz, Carl; Ajayan, Pulickel; Rice University; Saudi Arabian Oil Company; United States Patent and Trademark Office
    A process for making a layered multi-material structural element having controlled mechanical failure characteristics. The process includes the steps of: supplying a cementitious layer and forming a polymer layer on the cementitious layer by additive manufacture such that the polymer layer has a first thickness and the cementitious layer has a second thickness, wherein the polymer layer comprises a polymer and the cementitious layer comprises a cementitious material; and allowing the polymer from the polymer layer to suffuse into the cementitious layer for a period of time to obtain a suffused zone in the cementitious layer such that the suffused zone has a third thickness that is less than half the second thickness.
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    Additive manufacture-assisted method for making structural elements having controlled failure characteristics
    (2024-05-28) Sajadi, Seyed Mohammad; Meiyazhagan, Ashok Kumar; Boul, Peter; Rahman, Muhammad; Thaemlitz, Carl; Ajayan, Pulickel; Rice University; Saudi Arabian Oil Company; United States Patent and Trademark Office
    A process for making a layered multi-material structural element having controlled mechanical failure characteristics. The process includes the steps of: supplying a cementitious layer and forming a polymer layer on the cementitious layer by additive manufacture such that the polymer layer has a first thickness and the cementitious layer has a second thickness, wherein the polymer layer comprises a polymer and the cementitious layer comprises a cementitious material; and allowing the polymer from the polymer layer to suffuse into the cementitious layer for a period of time to obtain a suffused zone in the cementitious layer such that the suffused zone has a third thickness that is less than half the second thickness.
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    Chemical derivatization of single-wall carbon nanotubes to facilitate solvation thereof- and use of derivatized nanotubes
    (2004-12-28) Margrave, John L.; Mickelson, Edward T.; Hauge, Robert H.; Boul, Peter; Huffman, Chad; Liu, Jie; Smalley, Richard E.; Smith, Kenneth A.; Colbert, Daniel T.; Rice University; United States Patent and Trademark Office
    This invention is directed to making chemical derivatives of carbon nanotubes and to uses for the derivatized nanotubes, including making arrays as a basis for synthesis of carbon fibers. In one embodiment, this invention also provides a method for preparing single wall carbon nanotubes having substituents attached to the side wall of the nanotube by reacting single wall carbon nanotubes with fluorine gas and recovering fluorine derivatized carbon nanotubes, then reacting fluorine derivatized carbon nanotubes with a nucleophile. Some of the fluorine substituents are replaced by nucleophilic substitution. If desired, the remaining fluorine can be completely or partially eliminated to produce single wall carbon nanotubes having substituents attached to the side wall of the nanotube. The substituents will, of course, be dependent on the nucleophile, and preferred nucleophiles include alkyl lithium species such as methyl lithium. Alternatively, fluorine may be fully or partially removed from fluorine derivatized carbon nanotubes by reacting the fluorine derivatized carbon nanotubes with various amounts of hydrazine, substituted hydrazine or alkyl amine. The present invention also provides seed materials for growth of single wall carbon nanotubes comprising a plurality of single wall carbon nanotubes or short tubular molecules having a catalyst precursor moiety covalently bound or physisorbed on the outer surface of the sidewall to provide the optimum metal cluster size under conditions that result in migration of the metal moiety to the tube end.
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    Chemical derivatization of single-wall carbon nanotubes to facilitate solvation thereof; and use of derivatized nanotubes to form catalyst-containing seed materials for use in making carbon fibers
    (2003-11-11) Margrave, John L.; Mickelson, Edward T.; Hauge, Robert H.; Boul, Peter; Huffman, Chad; Liu, Jie; Smalley, Richard E.; Smith, Kenneth A.; Colbert, Daniel T.; Rice University; United States Patent and Trademark Office
    This invention is directed to making chemical derivatives of carbon nanotubes and to uses for the derivatized nanotubes, including making arrays as a basis for synthesis of carbon fibers. In one embodiment, this invention also provides a method for preparing single wall carbon nanotubes having substituents attached to the side wall of the nanotube by reacting single wall carbon nanotubes with fluorine gas and recovering fluorine derivatized carbon nanotubes, then reacting fluorine derivatized carbon nanotubes with a nucleophile. Some of the fluorine substituents are replaced by nucleophilic substitution. If desired, the remaining fluorine can be completely or partially eliminated to produce single wall carbon nanotubes having substituents attached to the side wall of the nanotube. The substituents will, of course, be dependent on the nucleophile, and preferred nucleophiles include alkyl lithium species such as methyl lithium. Alternatively, fluorine may be fully or partially removed from fluorine derivatized carbon nanotubes by reacting the fluorine derivatized carbon nanotubes with various amounts of hydrazine, substituted hydrazine or alkyl amine. The present invention also provides seed materials for growth of single wall carbon nanotubes comprising a plurality of single wall carbon nanotubes or short tubular molecules having a catalyst precursor moiety covalently bound or physisorbed on the outer surface of the sidewall to provide the optimum metal cluster size under conditions that result in migration of the metal moiety to the tube end.
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    Chemically modifying single wall carbon nanotubes to facilitate dispersal in solvents
    (2005-04-05) Margrave, John L.; Mickelson, Edward T.; Hauge, Robert H.; Boul, Peter; Huffman, Chad; Liu, Jie; Smalley, Richard E.; Smith, Kenneth A.; Colbert, Daniel T.; Rice University; United States Patent and Trademark Office
    This invention is directed to making chemical derivatives of carbon nanotubes and to uses for the derivatized nanotubes, including making arrays as a basis for synthesis of carbon fibers. In one embodiment, this invention also provides a method for preparing single wall carbon nanotubes having substituents attached to the side wall of the nanotube by reacting single wall carbon nanotubes with fluorine gas and recovering fluorine derivatized carbon nanotubes, then reacting fluorine derivatized carbon nanotubes with a nucleophile. Some of the fluorine substituents are replaced by nucleophilic substitution. If desired, the remaining fluorine can be completely or partially eliminated to produce single wall carbon nanotubes having substituents attached to the side wall of the nanotube. The substituents will, of course, be dependent on the nucleophile, and preferred nucleophiles include alkyl lithium species such as methyl lithium. Alternatively, fluorine may be fully or partially removed from fluorine derivatized carbon nanotubes by reacting the fluorine derivatized carbon nanotubes with various amounts of hydrazine, substituted hydrazine or alkyl amine. The present invention also provides seed materials for growth of single wall carbon nanotubes comprising a plurality of single wall carbon nanotubes or short tubular molecules having a catalyst precursor moiety covalently bound or physisorbed on the outer surface of the sidewall to provide the optimum metal cluster size under conditions that result in migration of the metal moiety to the tube end.
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    Damage-tolerant 3D-printed ceramics via conformal coating
    (AAAS, 2021) Sajadi, Seyed Mohammad; Vásárhelyi, Lívia; Mousavi, Reza; Rahmati, Amir Hossein; Kónya, Zoltán; Kukovecz, Ákos; Arif, Taib; Filleter, Tobin; Vajtai, Robert; Boul, Peter; Pang, Zhenqian; Li, Teng; Tiwary, Chandra Sekhar; Rahman, Muhammad M.; Ajayan, Pulickel M.
    Ceramic materials, despite their high strength and modulus, are limited in many structural applications due to inherent brittleness and low toughness. Nevertheless, ceramic-based structures, in nature, overcome this limitation using bottom-up complex hierarchical assembly of hard ceramic and soft polymer, where ceramics are packaged with tiny fraction of polymers in an internalized fashion. Here, we propose a far simpler approach of entirely externalizing the soft phase via conformal polymer coating over architected ceramic structures, leading to damage tolerance. Architected structures are printed using silica-filled preceramic polymer, pyrolyzed to stabilize the ceramic scaffolds, and then dip-coated conformally with a thin, flexible epoxy polymer. The polymer-coated architected structures show multifold improvement in compressive strength and toughness while resisting catastrophic failure through a considerable delay of the damage propagation. This surface modification approach allows a simple strategy to build complex ceramic parts that are far more damage-tolerant than their traditional counterparts. Conformal polymer coating leads to damage-tolerant architected ceramic structures with high strength and toughness. Conformal polymer coating leads to damage-tolerant architected ceramic structures with high strength and toughness.
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    Direct ink printing of multi-material composite structures
    (2024-01-02) Sajadi, Seyed Mohammad; Boul, Peter; Tiwary, Chandra Sekhar; Rahman, Muhammad M.; Ajayan, Pulickel M.; Thaemltiz, Carl; William Marsh Rice University; Saudi Arabian Oil Company; United States Patent and Trademark Office
    Methods for fabricating a multi-material composite structure are described. Methods for fabricating a multi-material composite structure include forming a first colloidal ink solution with a first material matrix, water, and a rheology modifying agent; forming a second colloidal ink solution with a second material matrix, water, and a rheology modifying agent; printing a first layer on a substrate using a first printing nozzle carrying the first colloidal ink solution; printing a second layer on top of the first layer using a second printing nozzle carrying the second colloidal ink solution; forming a 3D structure by printing a plurality of layers including the first layer and the second layer printed in an alternating pattern; and sintering the 3D structure to form the multi-material composite structure.
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    Dispersions and solutions of fluorinated single-wall carbon nanotubes
    (2004-12-07) Margrave, John L.; Mickelson, Edward T.; Hauge, Robert H.; Boul, Peter; Huffman, Chad; Liu, Jie; Smalley, Richard E.; Smith, Kenneth A.; Colbert, Daniel T.; Rice University; United States Patent and Trademark Office
    This invention is directed to making chemical derivatives of carbon nanotubes and to uses for the derivatized nanotubes, including making arrays as a basis for synthesis of carbon fibers. In one embodiment, this invention also provides a method for preparing single wall carbon nanotubes having substituents attached to the side wall of the nanotube by reacting single wall carbon nanotubes with fluorine gas and recovering fluorine derivatized carbon nanotubes, then reacting fluorine derivatized carbon nanotubes with a nucleophile. Some of the fluorine substituents are replaced by nucleophilic substitution. If desired, the remaining fluorine can be completely or partially eliminated to produce single wall carbon nanotubes having substituents attached to the side wall of the nanotube. The substituents will, of course, be dependent on the nucleophile, and preferred nucleophiles include alkyl lithium species such as methyl lithium. Alternatively, fluorine may be fully or partially removed from fluorine derivatized carbon nanotubes by reacting the fluorine derivatized carbon nanotubes with various amounts of hydrazine, substituted hydrazine or alkyl amine. The present invention also provides seed materials for growth of single wall carbon nanotubes comprising a plurality of single wall carbon nanotubes or short tubular molecules having a catalyst precursor moiety covalently bound or physisorbed on the outer surface of the sidewall to provide the optimum metal cluster size under conditions that result in migration of the metal moiety to the tube end.
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    Functionalized single-wall carbon nanotubes
    (2009-05-05) Margrave, John L.; Mickelson, Edward T.; Hauge, Robert H.; Boul, Peter; Huffman, Chad; Liu, Jie; Smalley, Richard E.; Smith, Kenneth A.; Colbert, Daniel T.; Rice University; United States Patent and Trademark Office
    This invention is directed to making chemical derivatives of carbon nanotubes and to uses for the derivatized nanotubes, including making arrays as a basis for synthesis of carbon fibers. In one embodiment, this invention also provides a method for preparing single wall carbon nanotubes having substituents attached to the side wall of the nanotube by reacting single wall carbon nanotubes with fluorine gas and recovering fluorine derivatized carbon nanotubes, then reacting fluorine derivatized carbon nanotubes with a nucleophile. Some of the fluorine substituents are replaced by nucleophilic substitution. If desired, the remaining fluorine can be completely or partially eliminated to produce single wall carbon nanotubes having substituents attached to the side wall of the nanotube. The substituents will, of course, be dependent on the nucleophile, and preferred nucleophiles include alkyl lithium species such as methyl lithium. Alternatively, fluorine may be fully or partially removed from fluorine derivatized carbon nanotubes by reacting the fluorine derivatized carbon nanotubes with various amounts of hydrazine, substituted hydrazine or alkyl amine. The present invention also provides seed materials for growth of single wall carbon nanotubes comprising a plurality of single wall carbon nanotubes or short tubular molecules having a catalyst precursor moiety covalently bound or physisorbed on the outer surface of the sidewall to provide the optimum metal cluster size under conditions that result in migration of the metal moiety to the tube end.
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    Methods of chemically derivatizing single-wall carbon nanotubes
    (2005-01-11) Margrave, John L.; Mickelson, Edward T.; Hauge, Robert H.; Boul, Peter; Huffman, Chad; Liu, Jie; Smalley, Richard E.; Smith, Kenneth A.; Colbert, Daniel T.; Rice University; United States Patent and Trademark Office
    This invention is directed to making chemical derivatives of carbon nanotubes and to uses for the derivatized nanotubes, including making arrays as a basis for synthesis of carbon fibers. In one embodiment, this invention also provides a method for preparing single wall carbon nanotubes having substituents attached to the side wall of the nanotube by reacting single wall carbon nanotubes with fluorine gas and recovering fluorine derivatized carbon nanotubes, then reacting fluorine derivatized carbon nanotubes with a nucleophile. Some of the fluorine substituents are replaced by nucleophilic substitution. If desired, the remaining fluorine can be completely or partially eliminated to produce single wall carbon nanotubes having substituents attached to the side wall of the nanotube. The substituents will, of course, be dependent on the nucleophile, and preferred nucleophiles include alkyl lithium species such as methyl lithium. Alternatively, fluorine may be fully or partially removed from fluorine derivatized carbon nanotubes by reacting the fluorine derivatized carbon nanotubes with various amounts of hydrazine, substituted hydrazine or alkyl amine. The present invention also provides seed materials for growth of single wall carbon nanotubes comprising a plurality of single wall carbon nanotubes or short tubular molecules having a catalyst precursor moiety covalently bound or physisorbed on the outer surface of the sidewall to provide the optimum metal cluster size under conditions that result in migration of the metal moiety to the tube end.
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    Sidewall derivatized carbon nanotubes
    (2010-08-24) Margrave, John L.; Mickelson, Edward T.; Hauge, Robert H.; Boul, Peter; Huffman, Chad; Liu, Jie; Smalley, Richard E.; Smith, Kenneth A.; Colbert, Daniel T.; Rice University; United States Patent and Trademark Office
    This invention is directed to chemical derivatives of carbon nanotubes wherein the carbon nanotubes have a diameter up to 3 nm. In one embodiment, this invention also provides a method for preparing carbon nanotubes having substituents attached to the side wall of the nanotube by reacting single-wall carbon nanotubes with fluorine gas and recovering fluorine derivatized carbon nanotubes, then reacting fluorine derivatized carbon nanotubes with a nucleophile. Some of the fluorine substituents are replaced by nucleophilic substitution. If desired, the remaining fluorine can be completely or partially eliminated to produce carbon nanotubes having substituents attached to the side wall of the nanotube. The substituents are dependent on the nucleophile, and preferred nucleophiles include alkyl lithium species such as methyl lithium.