Clay convertible by thermal treatment into crystalline mullite and silica is formed into green coherent bodies of desired size and shape such as, for example, microspheres, pellets or honeycombs. The bodies are then calcined to convert the clay into a mixture of crystalline mullite and silica, thereby also hardening the bodies. Without destroying the form of the bodies, e.g., without grinding and without causing the bodies to decrepitate, pores in the size range of about 150 to 350 A are formed ...

A process for the preparation of soft porous sheets, comprises forming into a sheet a composition comprising (i) 40 to 80% by weight of an inorganic filler and (ii) 60 to 20% by weight of a polyolefin type thermoplastic elastomer composition comprising at least 50% by weight of a polyolefin type thermoplastic elastomer substantially free of a polar group, in which the tensile stress at a temperature of 25.degree. C. under 100% stretching (100% modulus) is 10 to 100 Kg/cm.sup.2, the elongation at...

This invention provides a highly porous crosslinked functionalized polymer having interconnected cavities of micron dimensions and having a pore volume greater than about 5.6 cc/g and having a capacity to absorb water and also to absorb saline solutions. The polymers are generally based on styrene or various acrylates or mixtures and have a functional group selected from a large range of ionic and polar compositions.

Clay, preferably kaolin, is calcined through its exotherm, but without substantial mullite formation (e.g., 1 hour at 1000.degree. C.). The calcined clay is leached with an alkaline aqueous solution to remove (i.e., leach) silica. The severity of leaching, i.e., amount of silica removed, determines whether the final product will comprise mullite plus excess Al.sub.2 O.sub.3. If the molar Al.sub.2 O.sub.3 /SiO.sub.2 ratio is <3/2 the final product will contain mullite plus excess SiO.sub.2 and...

This invention discloses highly porous crosslinked functionalized polymers having interconnected cavities and a pore volume greater than 5.6 cc/g in the swollen state and having a capacity to absorb aqueous or organic acidic liquids from its dried state of at least 3 g liquid per gram of polymer. The polymers are generally based on styrene and/or methacrylate compositions and contain various ionic or polar functional groups.

This invention provides a highly porous crosslinked functionalised polymer having interconnected cavities of micron dimensions and having a pore volume greater than about 5.6 cc/g and having a capacity to absorb water and also to absorb saline solutions. The polymers are generally based on styrene or various acrylates or mixtures and have a functional group selected from a large range of ionic and polar compositions.

The present invention relates to a process for the manufacture of a porous polymer, wherein a composition comprising a polymerizable component, a porogen having an inverse temperature dependent solubility and a solvent are polymerized at a temperature around the cloud point temperature of the composition. The porous polymers obtainable according to the process of the invention are useful, for example, as materials for the manufacture of biomedical devices and prostheses, including ophthalmic dev...

Porous polyimide dielectric materials having low dielectric constants useful in electronic component manufacture are disclosed along with methods of preparing the porous polyimide dielectric materials. Also disclosed are methods of forming integrated circuits containing such porous polyimide dielectric material.

This invention relates to a novel method for the formation of porous hydrophilic membranes, to the membranes themselves, and to uses for them.

Porous dielectric materials having low dielectric constants useful in electronic component manufacture are disclosed along with methods of preparing the porous dielectric materials. Also disclosed are methods of forming integrated circuits containing such porous dielectric materials.