Mechanically strong, biodegradable and reusable aerogels are disclosed, which can be made with a cross-linked cellulose ester, and which exhibit a low density and high porosity. The aerogels disclosed herein may be used as sorbent materials and can be modified with a hydrophobic and/or oleophilic agent.

A thermally expandable composition, including at least one polymer, cross-linkable by peroxide, at least one peroxide, preferably at least one antioxidant, at least one chemical blowing agent, and at least one activator, wherein the activator includes at least one compound selected from formula (I), ##STR00001##
wherein radicals R.sup.1 and R.sup.4 represent hydrogen atoms or monovalent alkyl radicals with 1 to 10 carbon atoms which optionally include oxygen atoms; R.sup.2 and R.sup.3 represent hydrogen atoms or monovalent alkyl radicals with 1 to 10 carbon atoms which optionally include oxygen atoms, nitrogen atoms, and/or aromatic moieties or R.sup.2 and R.sup.3 together form a divalent alkyl radical with 1 to 10 carbon atoms which optionally includes oxygen atoms, nitrogen atoms or aromatic moieties. The composition shows excellent properties in terms of expansion stability over a wide temperature range, can be expanded at temperatures below 150° C. and is suitable for baffle and/or reinforcement elements.

A thermally expandable composition, including at least one polymer, cross-linkable by peroxide, at least one peroxide, preferably at least one antioxidant, at least one chemical blowing agent, and at least one activator, wherein the activator includes at least one compound selected from formula (I), ##STR00001##
wherein radicals R.sup.1 and R.sup.4 represent hydrogen atoms or monovalent alkyl radicals with 1 to 10 carbon atoms which optionally include oxygen atoms; R.sup.2 and R.sup.3 represent hydrogen atoms or monovalent alkyl radicals with 1 to 10 carbon atoms which optionally include oxygen atoms, nitrogen atoms, and/or aromatic moieties or R.sup.2 and R.sup.3 together form a divalent alkyl radical with 1 to 10 carbon atoms which optionally includes oxygen atoms, nitrogen atoms or aromatic moieties. The composition shows excellent properties in terms of expansion stability over a wide temperature range, can be expanded at temperatures below 150° C. and is suitable for baffle and/or reinforcement elements.

An article contains a polymeric foam board having a primary surface and an intumescent coating on a primary surface of the polymeric foam board, the intumescent coating containing a polymeric binder, expandable graphite particles, a phosphorous material and a boron-containing compound and wherein the article is free of an object that is in contact with the intumescent coating and that sandwiches the intumescent coating between it and the polymeric foam board and wherein the intumescent coating has a tensile elongation of at least 50 percent and less than 100 percent at 23 degrees Celsius as measured according to ISO 37, has a storage modulus of less than 1×10.sup.6 Pascals at 250 degrees Celsius, is halogen-free, free of sodium silicate, free of polyurea elastomer, and free of formals of pentaerythritol and dipentaerythritol.

The invention refers to a method for producing expanded polymer pellets, which comprises the following steps: melting a polymer comprising a polyamide; adding at least one blowing agent; expanding the melt through at least one die for producing an expanded polymer; and pelletizing the expanded polymer. The invention further concerns polymer pellets produced with the method as well as their use, e.g. for the production of cushioning elements for sports apparel, such as for producing soles or parts of soles of sports shoes. A further aspect of the invention concerns a method for the manufacture of molded components, comprising loading pellets of an expanded to polymer material into a mold, and connecting the pellets by providing heat energy, wherein the expanded polymer material of the pellets or beads comprises a chain extender. The molded components may be used in broad ranges of application.

The invention refers to a method for producing expanded polymer pellets, which comprises the following steps: melting a polymer comprising a polyamide; adding at least one blowing agent; expanding the melt through at least one die for producing an expanded polymer; and pelletizing the expanded polymer. The invention further concerns polymer pellets produced with the method as well as their use, e.g. for the production of cushioning elements for sports apparel, such as for producing soles or parts of soles of sports shoes. A further aspect of the invention concerns a method for the manufacture of molded components, comprising loading pellets of an expanded to polymer material into a mold, and connecting the pellets by providing heat energy, wherein the expanded polymer material of the pellets or beads comprises a chain extender. The molded components may be used in broad ranges of application.

A molding based on a monolithic organic aerogel has a density in the range from 60 to 300 kg/m.sup.3 and a thermal conductivity in the range from 12 to 17.8 mW/m*K. The molding based on a monolithic organic aerogel has more than 30 vol.-% of pores with a diameter of less than 150 nm, and more than 20 vol.-% of pores with a diameter of less than 27 nm, based on the total pore volume. A process can be used to prepare the molding by compression.

A molding based on a monolithic organic aerogel has a density in the range from 60 to 300 kg/m.sup.3 and a thermal conductivity in the range from 12 to 17.8 mW/m*K. The molding based on a monolithic organic aerogel has more than 30 vol.-% of pores with a diameter of less than 150 nm, and more than 20 vol.-% of pores with a diameter of less than 27 nm, based on the total pore volume. A process can be used to prepare the molding by compression.

A method for preparing core/shell particles includes forming a suspension of ethylenically unsaturated monomer droplets containing one or more monomers and a porogen in an aqueous medium containing a first stabilizer and a polymerization initiator, wherein at least one of the monomers is a cross-linking monomer, and wherein the first stabilizer is an inorganic colloid. The method further includes polymerizing the one or more monomers to form core/shell particles having a core of a porous polymer and a polymeric shell having a shell thickness of at least 5 nm, wherein any pores in the polymeric shell have a diameter of less than 2 nm.

Disclosed is a low-temperature supercritical foaming process, comprising the following steps: (1) bringing a polyolefin material or a thermoplastic elastomer material into contact with at least one inert gas in a reactor at a pressure higher than atmospheric pressure to drive the gas into the material, the pressure holding temperature of the polyolefin material or thermoplastic elastomer material being lower than the melting temperature of the material by 5-40° C.; (2) reducing the pressure to expand the material so as to produce a primary foamed material, and taking out the primary foamed material; and (3) taking out the primary foamed material and putting same into a tunnel furnace for secondary foaming, the temperature of the tunnel furnace being higher than the melting temperature of the material. Compared with the prior art, the present invention features high production efficiency, energy saving, and improvement of the reactor utilization rate.