Kureha Kagaku Kogyo K.k.

Kureha Corporation

Nobuo Sato

Zenya Shiiki

Yukichika Kawakami

Toshitaka Kouyama

Mitsuru Hoshino

Hiroyuki Sato

Hirohito Kawama

Koichi Suzuki

A process for producing a poly(arylene sulfide) including a charging step 1 of preparing a charging mixture containing an organic amide solvent, a sulfur source, an alkali metal hydroxide, water and a dihalo-aromatic compound and having a pH of at least 12.5; a first-stage polymerization step 2 of heating the mixture to initiate a polymerization reaction, thereby forming a prepolymer that a conversion of the dihalo-aromatic compound is at least 50%; and a second-stage polymerization step 3 of adding a phase separation agent into the reaction system and adding an alkali metal hydroxide in an amount corresponding to 1 to 10 mol % per mol of the charged sulfur source at a time or in portions, thereby continuing the polymerization reaction.

Production process of poly(arylene sulfide)

Gas-barrier, multi-layer hollow container

A composite gas barrier film having a layer structure comprises a thermoplastic resin film laminated on at least one side of a film formed from polyglycolic acid containing at least 60 wt. % of a repeating unit represented by the following formula (1):

Gas-barrier composite film

The invention provides an injection-molded product of polyglycolic acid obtainable by molding a thermoplastic resin material at an injection temperature ranging from the melting point, Tm of the polymer to 255&deg; C., wherein the thermoplastic resin material comprises polyglycolic acid having a repeating unit represented by the following formula (1):

Production process for injection-molded product of polyglycolic acid

The invention provides a stretch blow molded container formed from a thermoplastic resin material which comprises polyglycolic acid having (a) a repeating unit represented by the following formula (1): ##STR1## (b) a melt viscosity, .eta.* [as measured at a temperature of (the melting point, Tm of the polymer+20.degree. C.) and a shear rate of 100/sec] of 500-100,000 Pa.s; (c) a melting point, Tm of at least 180.degree. C.; (d) a melt enthalpy, .DELTA.Hm of at least 20 J/g; and (e) a density of at least 1.50 g/cm.sup.3 as measured in an unoriented, crystallized form, wherein the stretch blow molded container has tensile strength (in a circumferential direction) of at least 100 MPa and a carbon dioxide permeability (as measured at a temperature of 23.degree. C. and 80% relative humidity; in terms of the thickness of 50 .mu.m) of 300 cc/m.sup.2.day.atm or smaller at the body sidewall thereof, and a production process thereof.

Stretch blow molded container and production process thereof

An injection-molded product is obtained by injection molding a thermoplastic resin material. The thermoplastic resin material comprises a polyglycolic acid homopolymer or copolymer having a repeating unit represented by the following formula (1): ##STR1## in a proportion not lower than 70 wt. % and a repeating unit derived from at least one cyclic comonomer selected from the group consisting of ethylene oxalate and lactide in a proportion not higher than 30 wt. %, and having the following physical properties: (a) a melt viscosity, n*, measured at a temperature of the melting point, Tm, of the polyglycolic acid homopolymer or copolymer +20.degree. C. and a shear rate of 1,000/sec, of 30-10,000 Pa.multidot.s; (b) a melting point, Tm, of at least 150.degree. C.; (c) a melt enthalpy, .DELTA.Hm, of at least 20 J/g; and (d) a density of at least 1.50 g/cm.sup.3 as measured in an unoriented, crystallized form. The injection-molded product has Izod impact strength, unnotched, 25.degree. C., of at least 20 kJ/m.sup.2, tensile strength of a least 60 MPa, tensile elongation of at least 5%, flexural strength of at least 100 MPa, and flexural modulus of at least 5 GPa, and is obtained by injection molding at an injection temperature ranging from the melting point, Tm, of the homopolymer or copolymer to 255.degree. C.

Injection-molded product of polyglycolic acid and production process

The invention provides a stretch blow molded container formed from a thermoplastic resin material which comprises polyglycolic acid having

The invention provides a polyglycolic acid sheet obtainable by melt-extruding a thermoplastic resin material into a sheet in a temperature range of from the melting point, Tm of the polymer to 255.degree. C., wherein the thermoplastic resin material comprises polyglycolic acid having a repeating unit represented by the following formula (1): ##STR1## and the following physical properties: (a) the melt viscosity, .eta.* �as measured at a temperature of (the melting point, Tm of the polymer+20.degree. C.) and a shear rate of 100/sec! being 500-100,000 Pa.s;

Polyglycolic acid sheet and production process thereof

The invention provides an oriented polyglycolic acid film formed from a thermoplastic resin material which comprises polyglycolic acid having a repeating unit represented by the following formula (1): ##STR1## and the following physical properties: (a) the melt viscosity, .rho.* �as measured at a temperature of (the melting point, Tm of the polymer+20.degree. C.) and a shear rate of 100/sec! being 500-100,000 Pa.s;

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Fukushima, Japan

Nobuo Sato