Heat-expandable microspheres including a thermoplastic resin shell and a thermally-vaporizable blowing agent encapsulated therein. The thermoplastic resin is a polymer of a polymerizable component containing a cross-linkable monomer (A) which has at least two (meth)acryloyl groups per molecule and a reactive carbon-carbon double bond in addition to the (meth)acryloyl groups and has a molecular weight of at least 500. Also disclosed are hollow resin particles manufactured by expanding the heat-expandable microspheres; fine-particle-coated hollow resin particles including the hollow resin particles; a composition including a base component and the heat-expandable microspheres, or hollow resin particles, or fine-particle coated hollow resin particles; and a formed article manufactured by forming the composition.

Modification of the rheology of a liquid medium, aqueous or nonaqueous, with polymers in the form of specific particles obtained by grinding (micronizing) a porous macrogel, itself prepared by a process comprising a radical polymerization step which comprises reacting in the presence of pore formers monomers containing monomers bearing at least two ethylenic unsaturations, typically in combination with monomers bearing a single ethylenic unsaturation; a polymerization initiator; and optionally a polymerization control agent. These polymer particles keep other particles in suspension within the liquid medium, and also the stabilized suspensions are obtained.

Heat-expandable microspheres having a thermoplastic resin shell and a thermally-vaporizable blowing agent encapsulated therein. The thermoplastic resin is a copolymer produced from a polymerizable component containing 15 to 90 wt % of acrylonitrile, 3 to 50 wt % of an acrylate ester monomer (A) represented by formula (1) shown below, and 3 to 70 wt % of a methacrylate ester monomer (B) represented by formula (2) shown below. The weight ratio of the acrylate ester monomer (A) represented by formula (1) to the methacrylate ester monomer (B) represented by formula (2) in the polymerizable component (A:B) ranges from 10:90 to 90:10:
H.sub.2C═CH—COOR.sup.1  (1)
H.sub.2C═C(CH.sub.3)—COOR.sup.2  (2).
Also disclosed are hollow particles manufactured by expanding the heat-expandable microspheres; a composition containing a base compound and the heat-expandable microspheres or the hollow particles; and a formed product manufactured by molding or applying the composition.

Heat-expandable microspheres having a thermoplastic resin shell and a thermally-vaporizable blowing agent encapsulated therein. The thermoplastic resin is a copolymer produced from a polymerizable component containing 15 to 90 wt % of acrylonitrile, 3 to 50 wt % of an acrylate ester monomer (A) represented by formula (1) shown below, and 3 to 70 wt % of a methacrylate ester monomer (B) represented by formula (2) shown below. The weight ratio of the acrylate ester monomer (A) represented by formula (1) to the methacrylate ester monomer (B) represented by formula (2) in the polymerizable component (A:B) ranges from 10:90 to 90:10:
H.sub.2C═CH—COOR.sup.1  (1)
H.sub.2C═C(CH.sub.3)—COOR.sup.2  (2).
Also disclosed are hollow particles manufactured by expanding the heat-expandable microspheres; a composition containing a base compound and the heat-expandable microspheres or the hollow particles; and a formed product manufactured by molding or applying the composition.

Heat-expandable microspheres including a thermoplastic resin shell and a thermally-vaporizable blowing agent encapsulated therein. The thermoplastic resin is a polymer of a polymerizable component containing a cross-linkable monomer (A) which has at least two (meth)acryloyl groups per molecule and a reactive carbon-carbon double bond in addition to the (meth)acryloyl groups and has a molecular weight of at least 500. Also disclosed are hollow resin particles manufactured by expanding the heat-expandable microspheres; fine-particle-coated hollow resin particles including the hollow resin particles; a composition including a base component and the heat-expandable microspheres, or hollow resin particles, or fine-particle coated hollow resin particles; and a formed article manufactured by forming the composition.

Heat-expandable microspheres including a thermoplastic resin shell and a thermally-vaporizable blowing agent encapsulated therein. The thermoplastic resin is a polymer of a polymerizable component containing a cross-linkable monomer (A) which has at least two (meth)acryloyl groups per molecule and a reactive carbon-carbon double bond in addition to the (meth)acryloyl groups and has a molecular weight of at least 500. Also disclosed are hollow resin particles manufactured by expanding the heat-expandable microspheres; fine-particle-coated hollow resin particles including the hollow resin particles; a composition including a base component and the heat-expandable microspheres, or hollow resin particles, or fine-particle coated hollow resin particles; and a formed article manufactured by forming the composition.

The method produces hollow resin particles. The method comprising steps of: preparing a mixture liquid comprising (A) a monomer comprising at least one monomer selected from the group consisting of a monovinyl monomer and a hydrophilic monomer excluding acrylonitrile and methacrylonitrile, (B) a crosslinkable monomer, (C) an oil-soluble polymerization initiator, (E) a hydrocarbon solvent, (F) a suspension stabilizer and (G) an aqueous medium; carrying out a suspension treatment of the mixture liquid to prepare a suspension; carrying out a polymerization reaction of the suspension to prepare a precursor composition; carrying out a solid-liquid separation of the precursor composition to obtain the precursor particles; and removing the hydrocarbon solvent (E) included in the precursor particles.

The method produces hollow resin particles. The method comprising steps of: preparing a mixture liquid comprising (A) a monomer comprising at least one monomer selected from the group consisting of a monovinyl monomer and a hydrophilic monomer excluding acrylonitrile and methacrylonitrile, (B) a crosslinkable monomer, (C) an oil-soluble polymerization initiator, (E) a hydrocarbon solvent, (F) a suspension stabilizer and (G) an aqueous medium; carrying out a suspension treatment of the mixture liquid to prepare a suspension; carrying out a polymerization reaction of the suspension to prepare a precursor composition; carrying out a solid-liquid separation of the precursor composition to obtain the precursor particles; and removing the hydrocarbon solvent (E) included in the precursor particles.

The invention relates to the co-use of a) a certain type of silica and b) a certain type of graphite, wherein the silica and the graphite are used in a weight ratio in a range of from 1:1 to 1:10, for decreasing the thermal conductivity of vinyl aromatic polymer foam.

The invention relates to the co-use of a) a certain type of silica and b) a certain type of graphite, wherein the silica and the graphite are used in a weight ratio in a range of from 1:1 to 1:10, for decreasing the thermal conductivity of vinyl aromatic polymer foam.