摘要:
The present disclosure relates to a process for preparing coated cellulose nanocrystals (CNCs) and relates as well to coated cellulose nanocrystals (CNCs) obtainable by the process described herein. These new CNC hybrid nanomaterials are expected to be useful, for example, for the conjugation and electrostatic complexation with various functional moieties such as free metal ions, carboxylic acids, and epoxy and aldehyde derivatives. The disclosure further relates to a method to fabricate N-doped carbon nanomaterial from the coated CNCs.
摘要:
Novel polyarylamide derived activated carbon materials are provided by a process comprising the carbonization of polyarylamide fibre at a temperature in excess or 400.degree. C. followed by activation at elevated temperature. The novel materials have the ability to adsorb relatively large quantities or carbon dioxide compared to other activated carbonized polymer materials, Preferably the carbonization and activation steps are carried out by raising the temperature of the materials to between 840.degree. C. and 880.degree. C. in carbonizing/activating atmospheres respectively.
摘要:
A hollow filament comprising a filamentary polymer composed predominantly of a flame-resistant and anti-fusing cured novolak resin, characterized in that the hollow structure continuously extends in the axial direction of the filament, the degree of hollowness thereof being in the range of 10 - 80%, and a process for producing the same which comprises treating a filament consisting of a fiber-forming polymer of predominantly an uncured novolak resin composition, with a curing reagent in the presence of a curing catalyst to effect the cure of said filament extending from the peripheral portion to the axial portion thereof to a depth of 20-90% of the cross-sectional area of the filament, and thereafter removing the uncured core portion of said filament by extraction with a solvent.
摘要:
The internal structure of carbon fibers (as defined) is modified to yield a fibrous product having a bound oxygen content of about 3 to 30 percent by weight which exhibits substantially different bulk properties than that of the starting material. The carbon fiber precursor is contacted with a strong acid medium comprising nitric acid and optionally sulfuric acid and water (as defined) under conditions found capable of producing the desired internal chemical modification. In a preferred embodiment of the process the strong acid medium is formed by a combination (as defined) of fuming nitric acid and fuming sulfuric acid. The fibrous product exhibits, inter alia, reduced electrical and thermal conductivities, and particularly is suited for use as an ablative reinforcing medium.
摘要:
Nonflammable fibers are produced by subjecting a composite fiber comprising a pitch and a synthetic organic polymer bonded uniformly along the longitudinal direction of the fiber to an oxidation treatment to render it infusible and then to a set treatment in air or gaseous nitrogen at a temperature of 200* to 500* C. for at least 2 hours. The nonflammable fiber is converted to carbon fiber by heating to a temperature higher than 800* C. in gaseous nitrogen. Suitable pitches include petroleum asphalt, coal tar pitch, and pitch obtained by baking polyvinyl chloride. Suitable synthetic organic polymers include polyamides, polyesters, polyolefins, polyvinyl chloride, polyvinylidene chloride, polyurethane, epoxy resins, and phenol resins.
摘要:
Hybrid carbon nanofiber (Cnf) products (e.g., mats, yarns, webs, etc.) and methods of fabricating the same are provided. The hybrid Cnf products are flexible and lightweight and have high thermal conductivity. An electrospinning process can be used to fabricate the hybrid Cnf products and can include preparation of an electrospinning solution, electrospinning, and carbonization (e.g., under a vacuum condition).
摘要:
The present invention provides a carbonaceous material suitable for an electrode of a secondary cell. The carbonaceous material has a specific surface area by BET method of at least 10 m.sup.2 /g and a nitrogen/carbon atom weight ratio of 0.15 to 0.01, and is obtained by heat-treating a polyimide polymer having repeating units represented by: ##STR1## wherein R represents a 4 valent aromatic residue having at least one aromatic ring, of which each 2 valences are bonded with an adjacent carbon atom in the aromatic ring, R' represents a divalent aromatic residue having 1 to 4 aromatic rings and n is an integer of at least 2. The present invention also provides a secondary cell using the above mentioned carbonaceous material as electrode.
摘要:
MANUFACTURE OF CARBON SHAPED ARTICLE HAVING GAS IMPERMEABILITY, HIGH HARDNESS, AND HIGH MECHANICAL STRENGTH BY MIXING ORGANIC FIBER HAVING PARTICULAR PHYSICAL PROPERTIES WITH ORGANIC BINDER, OR A MIXTURE OF THE ORGANIC BINDER AND AN AGGREGATE, AND HEAT-TREATING THE MIXED MATERIAL.