The present invention relates to a method for producing biodegradable fibers on the basis of a silane compound, said silane compound being crosslinked during production and, at least to some extent, an organic acid being incorporated into the forming crosslinked structure via covalent bonds and/or contributing to the crosslinking. The present invention also relates to the fibers that can be produced by the method according to the invention and to the use thereof.

The current disclosure provides reinforced aerogel compositions that are durable and easy to handle, have favorable performance in aqueous environments, have favorable insulation properties, and have favorable, reaction to fire, combustion and flame-resistance properties. Also provided are methods of preparing or manufacturing such reinforced aerogel compositions. In certain embodiments, the composition has a silica-based aerogel framework, reinforced with an open-cell macroporous framework, and includes one or more fire-class additives, where the silica-based aerogel framework comprises at least one hydrophobic-bound silicon and the composition or each of its components has desired properties.

The current disclosure provides reinforced aerogel compositions that are durable and easy to handle, have favorable performance in aqueous environments, have favorable insulation properties, and have favorable, reaction to fire, combustion and flame-resistance properties. Also provided are methods of preparing or manufacturing such reinforced aerogel compositions. In certain embodiments, the composition has a silica-based aerogel framework, reinforced with an open-cell macroporous framework, and includes one or more fire-class additives, where the silica-based aerogel framework comprises at least one hydrophobic-bound silicon and the composition or each of its components has desired properties.

The present disclosure provides a high temperature, flame resistant and flexible coating composition based on alkali silicate and fluoropolymers. The coating can be used to bond a surface of a non-woven mat and seal the edges. The coating composition can be applied using a coating method on the surface and the edges of, for example, an inorganic fiber based non-woven mat.

Provided is a composite substrate for surface acoustic wave device which does not cause peeling of an entire surface of a piezoelectric single crystal film even when heating the film to 400° C. or higher in a step after bonding. The composite substrate is formed by providing a piezoelectric single crystal substrate and a support substrate, forming a film made of an inorganic material on at least one of the piezoelectric single crystal substrate and the support substrate, and joining the piezoelectric single crystal substrate with the support substrate so as to sandwich the film made of the inorganic material.

An object of the present invention is to provide a silicon oligomer having a novel function that has not been achieved by a conventional condensation product of water and a tetraalkoxysilane. Provided are a silicon oligomer represented by the following formula (I) and a production method therefor:

##STR00001## wherein R.sub.1 to R.sub.10 each independently is an alkyl group or a hydroxyalkyl group, each having 1 to 4 carbon atoms; X.sub.1 to X.sub.3 each independently is a group represented by the following formula (II); n is 0 or 1; and m is an integer of 1 to 3 when n is 0, and m is 1 when n is 1:

##STR00002## wherein A is an alkylene group having 2 to 4 carbon atoms which may be branched, and 1 is an integer of 1 to 3.

An object of the present invention is to provide a silicon oligomer having a novel function that has not been achieved by a conventional condensation product of water and a tetraalkoxysilane. Provided are a silicon oligomer represented by the following formula (I) and a production method therefor:

##STR00001## wherein R.sub.1 to R.sub.10 each independently is an alkyl group or a hydroxyalkyl group, each having 1 to 4 carbon atoms; X.sub.1 to X.sub.3 each independently is a group represented by the following formula (II); n is 0 or 1; and m is an integer of 1 to 3 when n is 0, and m is 1 when n is 1:

##STR00002## wherein A is an alkylene group having 2 to 4 carbon atoms which may be branched, and 1 is an integer of 1 to 3.

A curable organopolysiloxane composition contains: (A) 100 mass parts of a functional organopolysiloxane component having at least one radical curable group selected from an acrylate group and a methacrylate group and optionally one or more alkoxysilyl groups; (B) 0 to 100 mass parts of a condensation curable organo polysiloxane component; (C) one to 10 mass parts of tetraalkoxysilanes or a hydrolyate of the tetraalkoxysilanes; and optionally one or more of (D) a radical initiator, (E) a condensation catalyst, (F) fillers, (G) adhesion promoters, (H) pigments, (I) a non-reactive organopolysiloxane, and (J) inhibitors.

An aqueous dispersion of a silicone pressure sensitive adhesive base can be combined with a curing agent and cured to form a silicone pressure sensitive adhesive.

Disclosed are epoxy resins exhibiting a highly favorable combination of tensile strength and elongation with respect to prior art epoxy systems. The elastomeric epoxy resin systems of the invention are prepared utilizing a curing agent containing at least one monoprimary amine, and are particularly useful in applications such as, for example, castings, potting, composites, crack sealing, coatings, adhesives, roofing materials, flooring or reinforced membranes.