A porous fluorine resin film in which a fibril structure is stabilized through impregnation coating of a water-repellent and oil-repellent polymer having a high oil repellency grade, and free shrinkage also proceeds before impregnation and application of the water-repellent and oil-repellent polymer, thereby improving dimensional stability, and a method for preparing the porous fluorine resin film.

A method for producing an expanded rigid foam with sealed pores includes at least the following steps: a) a mixture is prepared containing at least: an anionic polymer suited for ionotropic gelation; a foaming agent; a source of multivalent cations, said multivalent cations not being released in the mixture a); and a solvent; b) the mixture is stirred so as to obtain a foam; c) a compound capable of releasing protons in a sufficient amount to release said multivalent cations is added to the foam such that the anionic polymer gels ionotropically; d) the foam is dried. A foam is obtained in this manner and an object (for example a package, a heat-insulating or flame-retardant material) is made from this foam.

A method for producing an expanded rigid foam with sealed pores includes at least the following steps: a) a mixture is prepared containing at least: an anionic polymer suited for ionotropic gelation; a foaming agent; a source of multivalent cations, said multivalent cations not being released in the mixture a); and a solvent; b) the mixture is stirred so as to obtain a foam; c) a compound capable of releasing protons in a sufficient amount to release said multivalent cations is added to the foam such that the anionic polymer gels ionotropically; d) the foam is dried. A foam is obtained in this manner and an object (for example a package, a heat-insulating or flame-retardant material) is made from this foam.

The polyolefin resin foam sheet is a polyolefin resin foam sheet having a plurality of cells in an inside thereof, wherein the 50% compressive strength is 120 kPa or less; the MD elongation percentage is 400% or less; and the TD elongation percentage is 200% or less.

A method of making an oil repellent sheet material according to an embodiment of the present disclosures includes a step of applying to a porous sheet a composition for forming an oil repellent layer, the composition containing a solvent and an amorphous fluorine resin dispersed therein, and a step of swaging the porous sheet after the step of applying, wherein the porous sheet has a fibrous skeleton composed mainly of polytetrafluoroethylene, the method of making an oil repellent sheet material further comprising a heat treatment step of heating the porous sheet to which the composition for forming an oil repellent layer is applied, before or after the step of swaging.

A sound absorber/insulator in a motor vehicle is constructed of outer layer nonwoven scrims, perforated films, and a fill material core, which are typically fibers or foams. Fibers could be of a nonorganic nature such as glass, or an organic one like polyester or cotton. Foams could be of open cell polyurethane chemistry. The materials are enveloped in a thermoforming process wherein all layers are substantially adhered to each other. The fill material is responsible for sound attenuation whereby a higher weight input provides additional attenuation benefit. Specialized technical nonwoven scrims can also be used to enhance the sound attenuation where required. Increasing absorption properties by adding weight or using highly technical nonwovens is costly and results in a weight penalty. Perforated films of certain thicknesses, hole sizes, and hole densities significantly enhance sound attenuation properties of an absorber and do so with no changes to the manufacturing process, a minimal increase in weight, and at a substantially lower cost. The films can be positioned in different locations throughout an insulator, depending on absorption requirements.

A sound absorber/insulator in a motor vehicle is constructed of outer layer nonwoven scrims, perforated films, and a fill material core, which are typically fibers or foams. Fibers could be of a nonorganic nature such as glass, or an organic one like polyester or cotton. Foams could be of open cell polyurethane chemistry. The materials are enveloped in a thermoforming process wherein all layers are substantially adhered to each other. The fill material is responsible for sound attenuation whereby a higher weight input provides additional attenuation benefit. Specialized technical nonwoven scrims can also be used to enhance the sound attenuation where required. Increasing absorption properties by adding weight or using highly technical nonwovens is costly and results in a weight penalty. Perforated films of certain thicknesses, hole sizes, and hole densities significantly enhance sound attenuation properties of an absorber and do so with no changes to the manufacturing process, a minimal increase in weight, and at a substantially lower cost. The films can be positioned in different locations throughout an insulator, depending on absorption requirements.

The invention relates to a method of preparing sub-micron biocarbon materials using biomass that is chemically modified with organic or inorganic agents including but not limited to acrylamide, glycine, urea, glycerol, bio-glycerol, corn syrup, succinic acid, and sodium bicarbonate. The use of foaming and heating methodologies which could be either pre or post carbonization and subsequent particle size reduction methodologies for the creation of cost-competitive sub-micron biocarbon particles and fibers for a variety of applications.

The invention relates to a method of preparing sub-micron biocarbon materials using biomass that is chemically modified with organic or inorganic agents including but not limited to acrylamide, glycine, urea, glycerol, bio-glycerol, corn syrup, succinic acid, and sodium bicarbonate. The use of foaming and heating methodologies which could be either pre or post carbonization and subsequent particle size reduction methodologies for the creation of cost-competitive sub-micron biocarbon particles and fibers for a variety of applications.

A closed cell crosslinked polyolefin foam sheet comprises an opposing first surface region and second surface region, and an intermediate region disposed therebetween, wherein the intermediate region is configured to have a gel content lower than an average gel content of the first surface region and the second surface region to enable a controlled tear propagation within the intermediate region when a splitting force is applied to the closed cell crosslinked polyolefin foam sheet. For example, a ratio of a gel content of the intermediate region versus an average gel content of the first surface region and the second surface region may be about 75% or less, and a ratio of the average cell size of the intermediate region versus an average cell size of the first surface region and the second surface region may be about 125% or higher.