US Patent 7655302 - Power transmission with nanotube fiber

http://www.freepatentsonline.com/7655302.html

In the 1990's a series of basic discoveries regarding carbon nanotubes were made by Richard Smalley's group at William Marsh Rice University. Patents based on this basic research are still being issued to Rice and are being commercialized by Unidym. This latest patent has priority going back to 1997 and is fundamental to power cabling systems based on carbon nanotube fibers. Claim 9 reads:

9. A high voltage power transmission cable

wherein at least one conductor comprises a continuous carbon fiber,

wherein the continuous carbon fiber comprises at least about 106 fullerene nanotubes bundled together in generally parallel orientation.

US Patent 7459137 - Solvent-free CNT functionalization

http://www.freepatentsonline.com/7459137.html

Due to molecular forces carbon nanotubes often bundle together making it necessary to include a solvent when functionalizing the nanoubes for applications such as biosensors. However, the requirement for solvent places a constraint on the type of environments and chemical reactions permitted for the functionalization. This patent from Rice University teaches methods of solvent-free functionalization of carbon nanotubes to expand the range of situations in which functionalization can occur. Claim 1 reads:

1. A method for functionalizing carbon nanotubes comprising:

a) selecting a plurality of carbon nanotubes; and

b) reacting said plurality of carbon nanotubes at the sidewall carbon atoms with an organic functionalizing agent in the absence of a solvent.

US Patents 7419624 + 7419651 - Fullerene nanotubes

http://www.freepatentsonline.com/7419624.html
http://www.freepatentsonline.com/7419651.html

Many of the basic fabrication methods for single walled nanotube production have come from research out of Rice University. While most of Rice's patents have previously focused on the single walled carbon nanotube type, a recent set of issued patents based on continuations (with priority going back to the 1990's) have extended the patent coverage to "fullerene nanotubes" which may include double or multiwall nanotubes types that are being explored as field emitters and transparent electrodes in electronics and display applications.

US Patent 7419624 - Claims 1 and 3

1. A method of producing a composite material comprising fullerene nanotube material, wherein said fullerene nanotube material comprises fibers of fullerene nanotubes, and wherein said method comprises:
(a) preparing an assembly of a fibrous material;
(b) adding said fullerene nanotube material to said fibrous material; and
(c) adding a matrix material to said fullerene nanotube material and said fibrous material.

3. A composite material comprising fullerene nanotubes, a fibrous structural constituent and a matrix material, wherein the matrix material comprises a polymer and the fibrous structural constituent comprises carbon, and wherein the fullerene nanotubes comprise fullerene nanotube fibers.

(US Patent 7419651) Claims 1 and 13

1. A three-dimensional structure that self-assembles from derivatized fullerene nanotubes comprising: a plurality of multifunctional fullerene nanotubes assembled into said three-dimensional structure.

13. A structure formed by the process comprising:
(a) providing fullerene nanotubes derivatized with at least one functionally-specific agent;
(b) exposing the derivatized nanotubes to another moiety for which the functionally-specific agent has an attraction; and
(c) recovering assemblies formed by the derivatized nanotubes.

US Patent 7413907 - Mass spectrometer using CNT mat

http://www.freepatentsonline.com/7413907.html

This patent from Rice University teaches using a functionalized mat of carbon nanotubes (i.e. bucky paper) as a binding matrix for analytes used in mass spectroscopy. Claim 1 reads:

1. A method for analyzing molecules with MALDI-MS comprising the steps of:

a) providing a mat of functionalized carbon nanotubes;

b) making a solution of analyte molecules in a suitable solvent;

c) contacting the analyte molecules with the mat of carbon nanotubes by placing a quantity of the analyte solution on the mat;

d) removing the solvent to form an analyte mat; and

e) performing MALDI-MS on the analyte mat.

US Patent 7407640 - Defunctionalizing CNT composites with radiation

http://www.freepatentsonline.com/7407640.html

Often in order to effectively incorporate carbon nanotubes in a polymer matrix the nanotubes need to be functionalized with another molecule for uniform distribution in the polymer and to avoid clumping of the nanotubes. However, this functionalization can also detract from the optimum properties offered by nanotubes such as high thermal and electrical conductivity. This patent from Rice University teaches defunctionalization of carbon nanotubes after incorporation in the polymer matrix to avoid the loss of the optimum properties of the nanotubes. Claim 1 reads:

1. A method comprising the steps of:

a) dispersing functionalized carbon nanotubes in a solvent to form a dispersion of functionalized carbon nanotubes;

b) incorporating the dispersion of functionalized carbon nanotubes into a polymer host matrix to form a functionalized carbon nanotube-polymer composite; and

c) modifying the functionalized carbon nanotube-polymer composite with radiation, wherein the modifying comprises defunctionalizing of the functionalized carbon nanotubes and wherein the radiation is selected from the group consisting of protons, neutrons, alpha particles, heavy ions, cosmic radiation, solar wind, and combinations thereof.

US Patent 7390477 - High purity nanotube compositions

http://www.freepatentsonline.com/7390477.html

This patent originating from Richard Smalley's group at Rice University is a continuation patent based on earlier patents with priority going back to 1997. These earlier patents were mostly focused on single walled carbon nanotubes, however this patent seems to broaden the scope to include a wider variety of nanotube types (multiwalled carbon nanotubes and perhaps even fullerene-like nanotubes formed from non-carbon materials such as boron nitride). Since multiwalled nanotubes may be easier to produce and useful as field emission material for displays, thermally conductive material for heat sinks, and electrically conductive material for flexible electrodes this patent may be particularly significant. Claim 1 reads:

1. A composition of matter comprising at least about 99% by weight of fullerene nanotubes.

US Patent 7384815 - Attaching molecular wires to carbon nanotubes

http://www.freepatentsonline.com/7384815.html

This patent from Rice University is fairly basic to the use of carbon nanotubes as components of molecular electronics devices. Claim 1 reads:

1. A process comprising: (a) derivatizing a carbon nanotube with a diazonium specie; and (b) covalently attaching a molecular wire to the derivatized carbon nanotube.

US Patent 7371457 - Core/shell optical nanoparticles

http://www.freepatentsonline.com/7371457.html

This patent from Rice University has fairly early priority (3/12/1997) and is basic to core/shell optical nanoparticles. Although not the first to teach such particles (see U.S. 5,023,139) the nanoparticles of the prior art are noted as not taking into account surface scattering and to have broader spectra whereas the claimed nanoparticles have a thin metallic shell layer providing a smaller electron mean free path for applications such as Surface Enhanced Raman Spectroscopy. Claim 1 reads:

1. A nanoparticle comprising:

at least one non-conducting inner layer;

at least one conducting shell layer surrounding the inner layer, the thickness of said shell layer being independent of the radius of said inner layer and less than the bulk electron mean free path of the material comprising the shell layer.

US Patent 7357906 - Single walled CNT separation

http://www.freepatentsonline.com/7357906.html

This patent originating from research by Richard Smalley's group at Rice University has priority going back to Aug. 8, 1996 and seems fairly basic to single walled carbon nanotube separation by type. Claim 1 reads:

1. A method comprising: a) providing a mixture of single-wall carbon nanotubes; b) derivatizing the single-wall carbon nanotubes; c) dispersing the single-wall carbon nanotubes; and d) fractionating the mixture by a characteristic selected from the group consisting of lengths, diameters, helicities and combinations thereof.

US Patent 7338915 - Conductive SWNT rope

http://www.freepatentsonline.com/7338915.html

This is one of a series of basic SWNT patents from Rice (with priority going back to 1995) and focuses on the metallic variety of single walled carbon nanotubes formed in relative abundance using a dual laser pulse method. Claim 1 reads:

1. A rope of single-wall carbon nanotubes having 50 to 5000 single-wall carbon nanotubes of which greater than 10% are (10, 10) single-wall carbon nanotubes.

US Patent 7323136 - Fullerene dispersion using levitation

http://www.freepatentsonline.com/7323136.html

One of the major roadblocks to using carbon nanotubes as strengthening material for metal composites is the agglomeration or clumping resulting in a poor distribution of the nanotubes. This patent from Rice University claims a method for forming a composite with a uniform distribution of carbon nanotubes or other fullerenes by using acoustic or electromagnetic levitation techniques. Claim 1 reads:

1. A method for forming a composite of dispersed fullerenes in a matrix, comprising: incorporating a plurality of fullerenes in a matrix, said incorporation forming a plurality of agglomerates; and uniformly distributing said fullerenes by exposing the agglomerates to heat and levitation; and aligning said fullerenes by shear flow during levitation.

US Patent 7306828 - Ceramic nanocomposite thermal barrier

http://www.freepatentsonline.com/7306828.html

Ceramic have been used in thermal barriers but due to their brittle properties have limited applicability. This patent from Rice University uses fullerene or carbon nanotube materials to enhance the mechanical characteristics of ceramic thermal barriers. Claim 1 reads:

1. A method of protecting a surface of an object with a thermal barrier, the method comprising: providing a mixture comprising (a) a ceramic host material and (b) a nanostructured carbon material selected from the group consisting of single-wall carbon nanotubes, multi-wall carbon nanotubes, vapor grown carbon fibers, fullerene molecules, carbon fibrils, buckyonions, nested fullerenes, endohedral fullerenes, metallofullerenes, and combinations thereof; heating the mixture so as to form a ceramic nanocomposite having a nanoporous structure; and coating the surface of the object with said ceramic nanocomposite.

US Patent 7304103 - Carbon nanotube functionalization using diazonium

http://www.freepatentsonline.com/7304103.html

Diazonium salts are organic molecular structures which have been useful in functionalizing single-walled carbon nanotubes. This patent from James Tour's group at Rice University (with priority going back to 2001) seems to be a basic patent covering such functionalization. Claim 1 reads:

1. A method for making a polymer material comprising: (a) derivatizing carbon nanotubes with functional moieties to form derivatized carbon nanotubes, wherein the functional moieties are derivatized to the carbon nanotubes utilizing a diazonium specie; (b) dispersing the derivatized carbon nanotubes in a polymer.

US Patent 7262266 - SWCNT block co-polymers

http://www.freepatentsonline.com/7262266.html

Block copolymers have an interesting property of self assembly used to form periodic structures on the nanoscale. This patent from Rice University teaches using single walled carbon nanotubes as a functional component of block co-polymers. Claim 1 reads:

1. A block copolymer comprising: a) a first block material comprising short single-wall carbon nanotubes (SWNTs); and b) a second block material comprising a rigid rod aromatic polymer.