Kaneka Corporation

Snt. Co., Ltd.

Tsuyoshi Mihayashi

Naruhiko Akamatsu

Yutaka Yanagihara

Kazumasa Ohara

Nobuhisa Ota

Takeshi Satoh

Kyoichi Nakamura

Kenji Mogami

Kohei Fukaya

Kenji Noda

Takayuki Goda

Satoshi Inamoto

Fumihiko Nakao

Mitsuharu Korogi

Hideshi Ito

Jin-Ho Kim

Oriha Kuwaki

A medical catheter tube containing a tetrafluoroethylene polymer, which has a wall thickness of 0.1 mm or below and exhibits a tensile strength (S1) at 1.0 mm displacement of 5.0 N/mm or above; and a process for the production of medical catheter tubes, characterized by molding a composition both a tetrafluoroethylene polymer and a lubricant having high affinity for the polymer by paste extrusion. The invention provides thin-wall medical catheter tubes excellent in elongation resistance, kink resistance and internal cavity lubricity.

Medical catheter tubes and process for production thereof

The present invention has its object to provide a resin composition for tubes excellent in balance among wear resistance, flexibility, gas permeation resistance and low resilience (pliability). The object is accomplished by a resin composition for tubes which comprises an isobutylene block copolymer (A) constituted of a polymer block (a) derived from isobutylene as a main constituent and a polymer block (b) derived from a monomer component other than isobutylene as a main constituent, and a thermoplastic polyurethane resin (B).

Resin composition for tubes and tube

The present invention relates to provide a catheter tube having excellent insertability into the body, excellent operability and an excellent anti-thrombogenic property, and also provide a catheter having the tube. For the purpose, a catheter tube of the present invention comprises a mixture of an isobutylene block copolymer and a thermoplastic polyurethane resin, wherein the isobutylene block copolymer is composed of a polymer block mainly comprising isobutylene and a polymer block mainly comprising a monomeric component other than isobutylene; and a catheter using the tube.

Catheter tube and catheter comprising the tube

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

The object of the present invention is to provide an in-mold foaming article of a propylene resin composition having improved productivity and stable quality in internal molding, and simultaneously a compressive strength and a tensile strength thereof at high density range are improved at the same time. The in-mold foaming article is obtained by using a pre-foamed particle having a density of 90 to 300 g/L and an open cell ratio of at most 12%, wherein the pre-foamed particle comprises a resin composition having (A) 100 parts by weight of a polypropylene resin and (B) 0.01 to 20 parts by weight of a hydrophilic polymer as a base material resin, and water as a foaming agent, the pre-foamed particle having at least two endothermic peaks in a DSC curve obtained in differential scanning calorimetry.

In-mold foaming article of polypropylene resin composition

There is provided pre-expanded particles of a propylene resin having a high expansion ratio and excellent molding adhesion without using a volatile blowing agent or increasing an expansion pressure. The pre-expanded particles of a propylene resin are prepared by the process comprising dispersing resin particles comprising a propylene resin composition, which contains 100 parts by weight of (A) a random copolymer of ethylene and propylene having an ethylene content of 1.5 to 4.5% by weight and 0.001 to 10 parts by weight of (B) an alkali metal salt of a copolymer of ethylene and (meth)acrylic acid, into an aqueous dispersion medium in a pressure vessel to obtain a mixture, heating the mixture to an expansion temperature higher than a softening temperature of the resin particles, introducing an inorganic gas, and releasing the mixture into a lower atmosphere than the inner pressure of the pressure vessel; said mixture is expanded after a temperature of said mixture is maintained at a temperature region of not more than the expansion temperature to at least (the expansion temperature &minus;1&deg; C.) for at least 30 minutes.

Pre-expanded particles of propylene resin, process for preparing the same and flow-restricting device

There is provided pre-expanded particles of a propylene resin having a high expansion ratio and excellent molding adhesion without using a volatile blowing agent or increasing an expansion pressure. The pre-expanded particles of a propylene resin are prepared by the process comprising dispersing resin particles comprising a propylene resin composition, which contains 100 parts by weight of (A) a random copolymer of ethylene and propylene having an ethylene content of 1.5 to 4.5% by weight and 0.001 to 10 parts by weight of (B) an alkali metal salt of a copolymer of ethylene and (meth)acrylic acid, into an aqueous dispersion medium in a pressure vessel to obtain a mixture, heating the mixture to an expansion temperature higher than a softening temperature of the resin particles, introducing an inorganic gas, and releasing the mixture into a lower atmosphere than the inner pressure of the pressure vessel; said mixture is expanded after a temperature of said mixture is maintained at a temperature region of not more than the expansion temperature to at least (the expansion temperature -1.degree. C.) for at least 30 minutes.

Pre-expanded particles of propylene resin, process for preparing the

A process for preparing polyolefin resin pre-expanded particles comprising imparting expandability to polyolefin resin expanded particles having a crystal structure which shows two melting points in a DSC curve and heat expanding expanded particles having expandability, in which the relation between heat expansion temperature and the amount of a fusion preventing agent being attached to the surface of the polyolefin resin expanded particles is represented by the inequality: t-T.sub.V .ltoreq.49.1C-27.0 (t is heat expansion temperature, C is the amount of the fusion preventing agent being attached to the surface of the polyolefin resin expanded particles and T.sub.V is saddle temperature between two peaks showing two respective melting points in the DSC curve), and t is within the temperature range represented by the inequality: T.sub.L -30.ltoreq.t.ltoreq.T.sub.V (T.sub.V is the same as defined above and T.sub.L is lower melting point of the two melting points). According to the process, mutual fusion of the expanded particles and increase of open cell ratio of the pre-expanded particles can be prevented at the same time, expansion efficiency can be increased, and polyolefin resin pre-expanded particles having high expansion ratio can be prepared.

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Settsu, Japan

Tsuyoshi Mihayashi