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.Math.m.sup.1.Math.K.sup.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.

An organic polymer aerogel that includes an organic polymer gel matrix and microstructures dispersed or embedded within the aerogel is disclosed. The aerogel can have an at least bimodal pore size distribution comprising a first peak of less than or equal to 65 nm and a second peak greater than or equal to 100 nm.

Disclosed are cellulose-based flexible aerogels and xerogels containing bacterial cellulose nanorods, ribbons, fibers, and the like, wherein the gels have tunable optical, heat transfer, and stiffness properties. Further disclosed are highly transparent and flexible cellulose nanofiber-polysiloxane composite aerogels featuring enhanced mechanical robustness, tunable optical anisotropy, and low thermal conductivity.

Disclosed are cellulose-based 5 flexible aerogels and xerogels containing bacterial cellulose nanorods, ribbons, fibers, and the like, wherein the gels have tunable optical, heat transfer, and stiffness properties. Further disclosed are highly transparent and flexible cellulose nanofiber-polysiloxane composite aerogels featuring enhanced mechanical robustness, tunable optical anisotropy, and low thermal conductivity.

The present invention relates to a method for preparing a cellulose sponge, comprising: (A) providing a solution of hydroxypropyl cellulose having a self-crosslinkable substituent; and (B) irradiating the solution of hydroxypropyl cellulose having the self-crosslinkable substituent with -ray for crosslinking, wherein a method for preparing the hydroxypropyl cellulose having the self-crosslinkable substituent comprises: (a) dissolving hydroxypropyl cellulose in dimethylformamide to form a hydroxypropyl cellulose solution; (b) dissolving a compound comprising the self-crosslinkable substituent in dimethylformamide and slowly adding it drop by drop into the hydroxypropyl cellulose solution; (c) adding alcohol for reaction; and (d) reacting and drying at room temperature to form the hydroxypropyl cellulose having the self-crosslinkable substituent. The present invention also relates to a mixed solution, comprising dimethylformamide, hydroxypropyl cellulose, a compound comprising a self-crosslinkable substituent and alcohol.

The present invention relates to a process for preparing a porous material, at least providing a mixture (I) comprising a composition (A) comprising components suitable to form an organic gel and a solvent(B), reacting the components in the composition (A) in the presence of the solvent (B) to form a gel, and drying of the gel obtained in step b), wherein the composition (A) comprises a catalyst (C) selected from the group consisting of alkali metal and earth alkali metal salts of a saturated or unsaturated monocarboxylic acid with 4 to 8 carbon atoms. 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, in particular in interior or exterior thermal insulation systems.

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 ?.sub.H in the range of 3.0 to 5.0 MPa-.sup.1, determined using the parameter ?.sub.H 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.

Aerogel is a dried product of wet gel being a condensate of sol containing at least one selected from the group consisting of a polysiloxane compound having a hydrolyzable functional group or a condensable functional group and having an average molecular weight of 300 to 1500 g/mol, and a hydrolysis product of the polysiloxane compound having a hydrolyzable functional group.

Polyurethane material for indicating pH at a locus, preferably as indication of presence of microbes, comprising a polyurethane network having immobilised therein one or more hydrophilic copolymers, the or each said copolymer comprising: hydrophilic monomer; and indicating monomer, which provides an indication in response to a change in hydrophilic state of said hydrophilic monomer and/or copolymer; characterised in that the or each copolymer further comprises one or a plurality of ionisable groups or moieties or polymerisable monomers having one or more characteristic pKa values in the range 5 to 10 and which are responsive to pH at the locus in the range pH 5 to pH 10 and in that hydrophilic state of hydrophilic copolymer is dependent on ionisation of said ionisable groups, moieties or monomers; kit and device comprising the material and process for preparation thereof; and use in detecting or sensing microbes or pH.

An aerogel that includes an open-cell structured polymer matrix is disclosed. The aerogel includes 5 wt. % to 50 wt. % of a polyamic amide polymer, based on the total weight of the aerogel, pores and at least 90% of the pore volume of the aerogel is made up of macropores, a porosity of at least 50%, as measure according to ASTM D4404-10, a density of 0.01 g/cm.sup.3 to 0.5 g/cm.sup.3, and the aerogel is thermally stable to resist browning at 330? C.