Kanegafuchi Kagaku Kogyo Kabushiki Kaisha

Kaneka Corporation

Kenji Mogami

Tadashi Koyama

Shunitsu Miyashita

Naruhiko Akamatsu

Akiyoshi Somemiya

Masaaki Nakamura

Tomomi Nakashima

Kenichi Senda

Kyoichi Nakamura

Kazuaki Matsumoto

Masahiro Asada

Kazushi Hirobe

Tsuyoshi Mihayashi

Yutaka Yanagihara

Ryoji Nakayama

Masahiko Mihoichi

Yasumitsu Munakata

Youichi Ohara

A polypropylene-based resin composition for injection foam molding, containing (A) 50 to 95 parts by weight of a linear polypropylene-based resin having a melt flow rate of from 10 g/10 min. to 100 g/10 min. and a melt tension of 2 cN or less and (B) 5 to 50 parts by weight of a modified polypropylene having a melt flow rate of from 0.1 g/10 min. to less than 10 g/10 min. and a melt tension of 5 cN or more and exhibiting a strain hardening property (provided that a total of the resin (A) and the resin (B) is 100 parts by weight) and a foaming agent are supplied to an injection molding machine to be injected into a die, thereby achieving a foam molding. It is thus possible to obtain a injection foamed molded article which has a satisfactory injection foam moldability, a skin layer having little silver streaks or the like on its surface, and an internal core layer having a foam of high expansion ratio and uniformly fine and a excellent appearance glossiness, lightweightness, and rigidity at a low cost.

Polypropylene based resin composition, expanded moldings comprising the same and method for production thereof

A water-containing polyolefin resin composition containing a polyolefin resin and a hydrophilic polymer and having a water content of 1 to 50% by weight which is suitable for use in preparation of polyolefin resin pre-expanded particles, and pre-expanded particles of a polyolefin resin prepared by pre-expanding the water-containing polyolefin resin composition the particles having a an apparent expansion ratio of 5 to 60, a closed cell ratio of 80 to 100% and an average cell diameter of 50 to 500 &mgr;m. The pre-expanded particles can be prepared without using a volatile blowing agent by dispersing resin particles made of a polyolefin resin composition containing a polyolefin resin and a hydrophilic polymer into an aqueous dispersion medium in a closed vessel to form a dispersion, heating to a temperature not lower than the softening point of the polyolefin resin to produce water-containing resin particles having a water content of 1 to 50% by weight, and releasing the aqueous dispersion from the closed vessel into a lower pressure than the inner pressure of the closed vessel, thereby expanding the water-containing resin particles. When the releasing of the dispersion from the vessel is conducted after raising the inner pressure to 25 to 75 kg/cm G by introducing nitrogen gas, air or an inorganic gas including them as a main component into the vessel, pre-expanded particles providing foams having good physical properties and a high expansion ratio are obtained.

Hydrous polyolefin resin composition, preexpanded particles produced therefrom, process for producing the same, and expanded molding

A process for preparing pre-expanded particles of a thermoplastic resin without washing the prepared pre-expanded particles to remove a dispersing agent remaining thereon and without discharging waste water, which comprises charging particles of a thermoplastic resin and an aqueous dispersion medium containing a dispersing agent into a closed pressure vessel, heating the resulting aqueous dispersion to a temperature of not less than the softening point of the thermoplastic resin, thereby impregnating the particles with water to have a water content of 1 to 50% by weight, releasing the dispersion into a lower pressure atmosphere, thereby expanding the particles, recovering the dispersion medium containing the dispersing agent, and recycling it as a dispersion medium to the pressure vessel.

Process for preparing pre-expanded particles of thermoplastic resin

There is provided a pre-expanded particle having a high expansion ratio and excellent flexibility and cushioning property. The in-mold articles made thereof do not lose mechanical strength, heat resistance, and water resistance, without conventional volatile organic foaming agents or carbon dioxide gas. A pre-expanded particle of a polypropylene resin is prepared by pre-expanding a water-containing propylene resin composition comprising (A) 100 parts by weight of a polypropylene resin having melt flow rate (230&deg; C., 2.16 kg load) of 10 to 70 g/10 min and tensile elongation at break of at least 300%, (B) 0.05 to 10 parts by weight of a hydrophilic polymer and (C) 0 to 3 parts by weight of a filler and having a water content of 1 to 20% by weight under a water vapor pressure at the melting point of the polypropylene resin, said particle having an apparent expansion ratio of 25 to 70 times, a closed cell content of at least 85% and an average cell diameter of 50 to 500 &mgr;m.

Water-containing polypropylene resin composition and pre-expanded particles made thereof

Polyethylene terephthalate resin composition

Flame-retardant resin composition

An additive having an improved dispersibility or adhesion property to thermoplastic resins and useful for imparting an excellent flame resistance and other properties thereto without deteriorating properties that the thermoplastic resins originally possess, such as mechanical, electrical and thermal properties and molding processability, which comprises a nitrogen-containing heterocyclic compound or its salt surface-treated with 0.1 to 50% by weight of a compound having at least two functional groups such as epoxy resin, acid anhydride or the like; and a flame retardant polyester resin composition comprising (A) a thermoplastic polyester, (B) a nitrogen-containing heterocyclic compound or its salt, (C) a compound having at least two functional groups and optionally (D) a phosphorus based flame retarder, which may be prepared by adding the component (B) previously surface-treated with the component (C) or separately adding the components (B) and (C) to the polyester (A).

Additive for thermpolastic resins and flame retardant resin composition

There are disclosed a resin composition capable of exhibiting a high melt viscoelasticity comprising 100 parts by weight of an aromatic copolyester resin which contains a branching component unit having at least three ester-forming groups in the ratio of 0.01 to 5 moles per 100 moles in total of aromatic dicarboxylic acid units and which has a limiting viscosity of 0.4 to 1.0 dl/g, and 0.05 to 5 parts by weight of a compound having at least two acid anhydride groups in its molecule, and an aromatic polyester resin foamed body produced therefrom and a process for producing the foamed body.

Resin composition capable of exhibiting high melt viscoelasticity,

A flame-retardant resin composition includes a thermoplastic polyester, a flame retardant containing an organic halide compound in an amount required for providing flame-retardancy, an antimony compound, and an alkoxidesilane compound in an amount required for providing thermostability. The flame-retardant resin composition has a high strength and excellent thermal stability.

A polyester resin composition having an improved molding processability and capable of providing molded articles having an improved impact resistance and other excellent properties such as mechanical strength and heat resistance, which comprises (a) a thermoplastic polyester, e.g. polyethylene terephthalate or a modified polyethylene terephthalate, (b) a polymer containing at least one epoxy group per molecule and having a modulus of elasticity of at most 10.sup.4 kg/cm.sup.2, e.g. an .alpha.-olefin/glycidyl ester or ether copolymer, and (c) a copolymer of an .alpha.-olefin and an .alpha.,.beta.-unsaturated carboxylic acid wherein at least 5% by mole of the carboxyl groups are neutralized with an alkali metal.

Polyester resin composition

A melt-blended resin composition useful as a modifier for improving the impact resistance of thermoplastic resins which comprises (a) a polymer containing at least one epoxy group per molecule and having a modulus of elasticity in bending of at most 10.sup.4 kg/cm.sup.2, e.g. an .alpha.-olefin/glycidyl ester or ether copolymer, and (b) a copolymer of an .alpha.-olefin and an .alpha.,.beta.-unsaturated carboxylic acid wherein at least 5% by mole of the carboxyl groups are neutralized with an alkali metal.

Resin composition

The present invention provides flame retardant resin compositions containing thermoplastic polyesters, organic halides and sodium antimonate, characterized in that the sodium antimonate has a ratio of the peak intensity of X-ray diffraction from face distances d of 5.25.about.5.35 (.ANG.) to that of 2.64.about.2.66 (.ANG.) being 1.5 or higher and mean particle diameter of 0.5.about.50 .mu.m, and is 1.about.15 parts by weight in proportion to 100 parts by weight of the aformentioned thermoplastic polyester. This invention provides thermoplastic resin compositions excellent in mechanical properties, hygroscopicity and thermal stability.

Growing community of inventors

Settsu, Japan

Kenji Mogami