Materials and methods for preparing thick, mesoporous silica monolithic slabs and coatings with high transparency and low thermal conductivity are provided. The transparent silica materials are particularly suited for window or solar applications including insulation barriers for existing or new single, double pane windows or glass panel building components. The template-free, water-based sol-gel methods produce slabs or coatings by gelation of a colloidal suspension of silica or other oxide nanoparticles or by ambigel formation and then ageing and drying the gels under ambient conditions. Solvent exchanges with nonpolar, low-surface-tension solvents help to avoid cracking caused by drying stress. Mesoporous slabs can also be cast in molds on perfluorocarbon liquid substrates to reduce adhesion and enable gels to shrink freely during aging and drying without incurring significant stress that could cause fracture.

The present invention relates to a method for producing a silica aerogel and a silica aerogel produced thereby. More specifically, a first water glass solution is used to form a first silica wet gel, and then a second water glass solution is additionally added to form a second silica wet gel organically bonded to the first silica wet gel which serves as a basic skeleton, so that a silica aerogel with enhanced physical properties is formed to increase the resistance to shrinkage in ambient drying. Thus, a low-density silica aerogel may be formed, and the concentrations of the first and second water glass solutions may be adjusted to control the physical properties of the silica aerogel.

The invention relates to a method for producing aerogels, in particular silica aerogels, by way of a sol-gel process.

A heat-insulation material does not cause deterioration in heat-insulation performance and any loss of components included therein, and possesses an excellent radiation-preventing function. The heat-insulation material includes: a first heat-insulation layer that includes a first silica xerogel and a first radiation-preventing material; and a third heat-insulation layer that includes a third silica xerogel and second fibers, wherein the first heat-insulation layer and the third heat-insulation layer are layered. An electronic device includes the heat-insulation material. Yet further disclosed is a method for producing the heat-insulation material.

The problem addressed by the invention is that of producing aerogels which have as high and permanent a hydrophobicity as possible and which have a reduced combustibility, that is as low a carbon content as possible, and are simultaneously less rigid and brittle than known systems, i.e. which with reduced combustibility have a high flexibility and high stability at the same time, that is high mechanical load-bearing capacity. Said problem is solved in that the invention provides gels chosen from lyogel or aerogel, which are synthesised from oxide units and [R.sub.xSiO.sub.(4-x)/2] units, wherein the primary particles have a change of concentration in [R.sub.xSiO.sub.(4-x)/2] units from the inside to the outside, wherein x can be the same or different and is 1 or 2, and R can be the same or different and is hydrogen or an organic substituted or unsubstituted radical, and wherein the oxide units contain [SiO.sub.4/2] units, and a method for producing same. The gels provided can be used in cosmetic, medical or for chromatographic applications, and as a catalyst or catalyst support. If the gels are aerogels, same are preferably used for thermal and/or acoustic insulation.

It is an object of the invention to provide an economically viable process for the production of hydrophobized aerogels which works both inexpensively and in a resource-conserving manner. 2.2. This object is achieved by the provision of a process for producing organically modified aerogels by producing a sol containing [SiO.sub.4/2] units and [R.sub.xSiO.sub.(4X)/2] a units, where x may be the same or different and is 1, 2 or 3, and R may be the same or different and is hydrogen or an organic substituted or unsubstituted radical, using the sol to form a gel, surface-modifying the gel obtained in the presence of more than 0.1% by weight of a phase modifier in a mixture comprising organosiloxane and initiator, wherein the mixture contains at least 20% by weight of organosiloxane and wherein the initiator consists of acid or organosiloxane or mixtures thereof and the gels obtained are dried. 2.3. The aerogels provided can be used as insulating materials, especially in thermal insulation.

It is an object of the invention to provide an economically viable process for the production of hydrophobized aerogels which works both inexpensively and in a resource-conserving manner. 2.2. This object is achieved by the provision of a process for producing organically modified aerogels by producing a sol containing [SiO.sub.4/2] units and [R.sub.xSiO.sub.(4X)/2] a units, where x may be the same or different and is 1, 2 or 3, and R may be the same or different and is hydrogen or an organic substituted or unsubstituted radical, using the sol to form a gel, surface-modifying the gel obtained in the presence of more than 0.1% by weight of a phase modifier in a mixture comprising organosiloxane and initiator, wherein the mixture contains at least 20% by weight of organosiloxane and wherein the initiator consists of acid or organosiloxane or mixtures thereof and the gels obtained are dried. 2.3. The aerogels provided can be used as insulating materials, especially in thermal insulation.

The present invention relates to a method for producing an aerogel blanket exhibiting excellent hydrophobicity at high temperatures and an aerogel blanket produced thereby. The present invention uses a mixture of silica sol and a hydrophobic aerogel powder as an aerogel precursor and thus can achieve hydrophobicity in the internal structure as well as on the surface of the aerogel included in the aerogel blanket. Accordingly, the aerogel blanket can attain high hydrophobicity and thus can exhibit excellent hydrophobicity retention ability even in high-temperature applications.

The present invention relates to aerogels, and more particularly to ambient pressure methods for the synthesis of silica aerogels. In embodiments, the invention relates to methods for preparing controlled-shape fibre reinforced silica aerogel composites.

A method for forming a ceramic aerogel includes contacting a ceramic precursor, an additive, an anionic surfactant, a cationic surfactant, and a catalyst to form a mixture. The catalyst may include an acid or a base. The method further includes heating the mixture to form a precursor gel, mixing fibers with the precursor gel, and drying the resultant fiber containing precursor gel.