Tokuyama Sekisui Co. | Date: 2012-11-30
Chlorinated vinyl chloride resin may be produced through a heat chlorination reaction of an aqueous suspension of vinyl chloride resin in a hermetically sealable reaction vessel, the method including carrying out a first heat chlorination reaction while raising the temperature of an aqueous suspension of a vinyl chloride resin powder to a predetermined temperature within the range of 85 C. to 95 C., and subsequently carrying out a second heat chlorination reaction at the predetermined temperature.
Sekisui Chemical Co., Sekisui Chemical Hokkaido Co. and Tokuyama Sekisui Co. | Date: 2012-11-29
A thermally expandable multilayer packing for building material, having protruding parts and a body portion in the cross-sectional shape based a plane perpendicular to the longitudinal direction. The thermally expandable multilayer packing includes both a thermally expandable resin composition layer and a thermoplastic resin composition layer, wherein the thermally expandable resin composition forming the thermally expandable resin composition layer contains 100 parts by weight of a resin component containing a chlorinated polyvinyl chloride resin and/or an EPDM, 3 to 300 parts by weight of a thermally expandable graphite, 3 to 200 parts by weight of an inorganic filler and 20 to 200 parts by weight of a plasticizer. The thermally expandable resin composition layer and the thermoplastic resin composition layer are formed by simultaneous co-extrusion using the thermally expandable resin composition and the thermoplastic resin composition.
Sekisui Chemical Co. and Tokuyama Sekisui Co. | Date: 2012-11-29
A chlorinated vinyl chloride resin composition for extrusion molding, characterized by: containing 100 parts by weight of a chlorinated vinyl chloride resin, 3 to 300 parts by weight of a thermally expandable graphite, 3 to 200 parts by weight of an inorganic filler and 20 to 200 parts by weight of a plasticizer; and containing no phosphorus compound (excluding phosphate plasticizer). A chlorinated vinyl chloride resin having a chlorine content of 60 to 72% by weight can be used as the resin component for extrusion molding.
Sekisui Chemical Co. and Tokuyama Sekisui Co. | Date: 2014-09-22
The present invention provides a thermally expandable microcapsule that has a high expansion ratio and durability at high temperatures, and is not likely to cause discoloration and odor when used for foam molding. The thermally expandable microcapsule of the present invention includes: a shell formed from a polymer; and a volatile expansion agent as a core agent encapsulated by the shell, the shell obtained by polymerizing a monomer composition that contains a nitrile monomer and a compound having a glycidyl group in a molecule, the shell exhibiting a value y of 50% or higher and a ratio y/x of 1.1 or higher, in which x represents a gel fraction at ordinary temperature, and y represents a gel fraction upon heating at 180 C. for 30 minutes.
Kawaguchi Y.,High Performance Functional Plastics Company |
Ito D.,High Performance Functional Plastics Company |
Kosaka Y.,High Performance Functional Plastics Company |
Okudo M.,High Performance Functional Plastics Company |
And 5 more authors.
Polymer Engineering and Science | Year: 2010
A new thermally expandable microcapsule was developed for use with foaming polypropylene (PP) by injection molding and extrusion processes at operating temperatures above 200°C. The microcapsule consists of a blowing agent as the core and a shell polymer. The rheological properties of the shell polymer were controlled by a crosslinking agent to design the expandability and shrinkage. The effects of rheological properties on the expandability and the surface appearance of foam products were thoroughly investigated. It was found that storage modulus G' and tan α significantly affected the expandability and shrinkage and were controllable through crosslinking polymerization. Visual observation of batch foaming, rheological measurement, and experiments of foam injection molding and extrusion elucidated the existence of the optimal degree of crosslinking that could realize more than 30% density reduction while maintaining a smooth surface at PP foam injection molding and extrusion. POLYM. ENG. SCI., 50:835-842, 2010. © 2009 Society of Plastics Engineers. Source