Polysilocarb formulations, cured and pyrolized materials, was well as articles and use for this material. In particular pyrolized polysilocarb ceramic materials and articles contain these materials where, the ceramic has from about 30 weight % to about 60 weight % silicon, from about 5 weight % to about 40 weight % oxygen, and from about 3 weight % to about 35 weight % carbon, and wherein 20 weight % to 80 weight % of the carbon is silicon-bound-carbon and 80 weight % to about 20 weight % of the carbon is free carbon.

Polysilocarb formulations, cured and pyrolized materials, was well as articles and use for this material. In particular pyrolized polysilocarb ceramic materials and articles contain these materials where, the ceramic has from about 30 weight % to about 60 weight % silicon, from about 5 weight % to about 40 weight % oxygen, and from about 3 weight % to about 35 weight % carbon, and wherein 20 weight % to 80 weight % of the carbon is silicon-bound-carbon and 80 weight % to about 20 weight % of the carbon is free carbon.

Polysilocarb formulations, cured and pyrolized materials, was well as articles and use for this material. In particular pyrolized polysilocarb ceramic materials and articles contain these materials where, the ceramic has from about 30 weight % to about 60 weight % silicon, from about 5 weight % to about 40 weight % oxygen, and from about 3 weight % to about 35 weight % carbon, and wherein 20 weight % to 80 weight % of the carbon is silicon-bound-carbon and 80 weight % to about 20 weight % of the carbon is free carbon.

Nanocomposite silicon and carbon compositions. These compositions can be made from polymer derived ceramics, and in particular, polysilocarb precursors. The nanocomposite can have non-voids or be nano-void free and can form larger macro-structures and macro-composite structures. The nanocomposite can contain free carbon domains in an amorphous SiOC matrix.

Nanocomposite silicon and carbon compositions. These compositions can be made from polymer derived ceramics, and in particular, polysilocarb precursors. The nanocomposite can have non-voids or be nano-void free and can form larger macro-structures and macro-composite structures. The nanocomposite can contain free carbon domains in an amorphous SiOC matrix.

The present invention is related to a curable composition for dental impression comprising: a curable base composition and a surfactant system comprising a first surfactant, which is at least one compound having the formula (I) and a second surfactant, which works synergistically with the second surfactant so as to permit the composition to surprisingly have a lower contact angle; these results are reached with relatively low concentrations of biodegradable surfactants.

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The present invention is related to a curable composition for dental impression comprising: a curable base composition and a surfactant system comprising a first surfactant, which is at least one compound having the formula (I) and a second surfactant, which works synergistically with the second surfactant so as to permit the composition to surprisingly have a lower contact angle; these results are reached with relatively low concentrations of biodegradable surfactants.

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An extrudable ceramic precursor mixture and method of use includes: an inorganic ceramic-forming component, a first siloxane prepolymer, a second siloxane prepolymer with a different composition than the first siloxane prepolymer, a catalyst adapted to catalyze polymerization of the first siloxane prepolymer with the second siloxane prepolymer into a siloxane-based polymer, and a thermally curable siloxane-based cross-linking agent adapted to crosslink the siloxane-based polymer. Comprised is a polydimethylsiloxane having a vinyl functional group and a polydimethylsiloxane having a silicon hydride functional group.

An extrudable ceramic precursor mixture and method of use includes: an inorganic ceramic-forming component, a first siloxane prepolymer, a second siloxane prepolymer with a different composition than the first siloxane prepolymer, a catalyst adapted to catalyze polymerization of the first siloxane prepolymer with the second siloxane prepolymer into a siloxane-based polymer, and a thermally curable siloxane-based cross-linking agent adapted to crosslink the siloxane-based polymer. Comprised is a polydimethylsiloxane having a vinyl functional group and a polydimethylsiloxane having a silicon hydride functional group.

An object is to provide a heat conductive sheet having good handleability when mounting between the heating element and the heat dissipator, and softness that enables the distortion of the heating element, the heat dissipator, and the like to be suppressed in use. The heat conductive sheet contains: a matrix comprising a cured product of organopolysiloxane; and heat conductive fillers comprising anisotropic fillers with their major axes oriented in the thickness direction, and has a load property P represented b formula (1) below of 0.1 to 0.7: Load property P=(F.sub.30−F.sub.20)/F.sub.10 (1) wherein F.sub.10 is a load of the heat conductive sheet at 10% compression, F.sub.20 is a load of the heat conductive sheet at 20% compression, and F.sub.30 is a load of the heat conductive sheet at 30% compression.