摘要:
The present invention relates to a process for producing porous materials, which comprises providing a mixture comprising a composition (A) comprising components suitable to form an organic gel and a solvent mixture (B), reacting the components in the composition (A) in the presence of the solvent mixture (B) to form a gel and drying of the gel, wherein the solvent mixture (B) is a mixture of at least two solvents and the solvent mixture has a Hansen solubility parameter δH in the range of 3.0 to 5.0 MPa−1, determined using the parameter δH of each solvent of the solvent mixture (B). The invention further relates to the porous materials which can be obtained in this way and the use of the porous materials as thermal insulation material and in vacuum insulation panels.
摘要:
The sol-gel templating with the infusion of gas bubbles provides a process for synthesizing polymeric or gel materials while being templated with slow bubbling of various gases into the reacting media upon the polymerization or gelation stage. The process uses a source of gas, which is delivered at a desired rate and pressure via at least one inert tube directly into the reacting solution while the gel is being formed by sol-gel process. The tube(s) have a diameter selected to produce bubbles that result in the desired pore size and the number and placement of the tubes is selected to produce the desired pore structure and surface area in the gel template. The gel may be any gel capable of being formed by sol-gel process. The gas may be selected from carbon dioxide, methane, nitrogen, helium, argon, oxygen, hydrogen, propane, ethane, propylene, ethylene, air, and n-butane and other inert gases.
摘要:
A non-crosslinked, gelled carbonaceous composition and a pyrolysed composition respectively forming an aqueous polymer gel and the pyrolysate thereof in the form of porous carbon is provided. Also provided is a production method thereof, to a porous carbon electrode formed by the pyrolysed composition, and to a supercapacitor containing the electrodes. The gelled, non-crosslinked composition (G2) is based on a resin created at least partly from polyhydroxybenzene(s) R and formaldehyde(s) F and comprises at least one hydrosoluble cationic polyelectrolyte P. The composition forms a rheofluidifying physical gel. A pyrolysed carbonaceous composition having a carbon monolith, is the product of coating, crosslinking, drying then pyrolysis of the non-crosslinked gelled composition, the carbon monolith being predominantly microporous and able to form a supercapacitor electrode having a thickness of less than 1 mm.
摘要:
Provided is a gelled carbon-based composition forming an organic polymeric monolithic gel capable of forming a porous carbon monolith by pyrolysis, a use thereof and a process for preparing this composition. A composition according to the invention is based on a resin derived at least partly from polyhydroxybenzene(s) R and formaldehyde(s) F, has a thermal conductivity of less than or equal to 40 mW·m−1·K−1, and includes at least one water-soluble cationic polyelectrolyte P. A process for preparing this composition comprises: a) polymerization, in an aqueous solvent, of the polyhydroxybenzene(s) and formaldehyde(s), in the presence of at least one cationic polyelectrolyte dissolved in this solvent and of a catalyst, in order to obtain a solution based on the resin, b) gelling of the solution in order to obtain a gel, and c) drying in order to obtain the organic polymeric monolithic gel.
摘要:
The present invention relates to a process for producing pulverulent organic porous materials, comprising (i) the provision of an organic xerogel or organic aerogel and then (ii) the comminution of the material provided in step (i).The invention further relates to the pulverulent organic porous materials thus obtainable, to thermal insulation materials comprising the pulverulent porous organic materials, to building material and vacuum insulation panels comprising the thermal insulation materials, and to the use of the pulverulent organic porous materials or of the thermal insulation materials for thermal insulation.