Kureha Corporation

Nissan Chemical Industries Limited

Asahi Glass Company, Limited

Nfe Co., Ltd.

Akihiro Konno

Hiroyuki Sato

Ken-Ichi Takaki

Atsuo Murata

Yasuhiro Suzuki

Hiroshi Sakabe

Shuji Tsuchiya

Yui Yoshida

Haruki Mokudai

Hisao Ikeda

Akira Yanagimoto

Jun Uchida

Syuji Tsuchiya

Fumiyoshi Arima

Kunihiko Takabe

Masaru Iida

Michio Yamada

Takashi Harunari

Toshiyasu Okamura

Juntaro Tanaka

The present invention provides a method for producing granular polyarylene sulfide (PAS) with increased average particle size and enhanced particle strength, a method for increasing the average particle size of granular PAS, a method for enhancing the particle strength of granular PAS, and granular PAS. The method for producing PAS according to the present invention includes: step 1: a preparation step of preparing a mixture containing an organic amide solvent, a sulfur source, water, a dihalo aromatic compound, and an alkali metal hydroxide; step 2: a pre-stage polymerization step of initiating a polymerization reaction by heating the mixture to produce a prepolymer having a dihalo aromatic compound conversion ratio of not less than 50% in the presence of less than an equimolar amount of an alkali metal hydroxide per 1 mol of the sulfur source; step 3: a post-stage polymerization step of continuing the polymerization reaction in the presence of not less than an equimolar amount of an alkali metal hydroxide per 1 mol of the sulfur source to obtain a reaction product mixture; and step 4: a cooling step of cooling the reaction product mixture after the post-stage polymerization step; wherein step 4 is performed in the presence of at least one type of auxiliary agent such as a carboxylate.

Method for producing granular polyarylene sulfide, method for increasing average particle size of granular polyarylene sulfide, method for enhancing particle strength of granular polyarylene sulfide, and granular polyarylene sulfide

The present invention is to provide a method that can produce polyarylene sulfide having a high viscosity at a high yield. The method of producing polyarylene sulfide according to an embodiment of the present invention includes: a preparation step of preparing a mixture containing an organic amide solvent, a sulfur source, a dihalo aromatic compound, and an alkali metal hydroxide; a first-stage polymerization step of initiating a polymerization reaction by heating the mixture and producing a prepolymer until a pH of a reaction system reaches a range of 10 to 11; and a second-stage polymerization step of continuing the polymerization reaction.

Method of producing polyarylene sulfide

A method of producing a polyarylene sulfide (PAS) includes a preparation step of preparing a charged mixture containing an organic amide solvent, a sulfur source, water, and a dihalo aromatic compound; a first-stage polymerization step of performing a polymerization reaction on the charged mixture at a temperature of from 170 to 280&#xb0; C. to produce a prepolymer having a conversion ratio of the dihalo aromatic compound of 50% or greater; and a second-stage polymerization step of continuing the polymerization reaction in a phase-separated state at a temperature of from 245 to 290&#xb0; C. in a reaction system containing the prepolymer, and includes adding a polyfunctional compound to the reaction system in the phase-separated state. A PAS having a melt viscosity (310&#xb0; C., shear rate: 1216 sec) of from 0.1 to 8000 Pa&#xb7;s is produced by the method.

Polyarylene sulfide production method and polyarylene sulfide

Provided is a method of producing polyarylene sulfide at low cost while productivity enhancement and resource saving are attempted by avoiding the use of a complicated step and special apparatus (facility). The method of producing polyarylene sulfide according to an embodiment of the present invention includes: a preparation step of preparing a mixture containing an organic amide solvent, a sulfur source, a dihalo aromatic compound, and an alkali metal hydroxide in an amount less than an equimolar amount relative to an amount of the sulfur source; a first-stage polymerization step of initiating a polymerization reaction by heating the mixture, and producing a prepolymer having a dihalo aromatic compound conversion ratio of 50% or greater; and a second-stage polymerization step of adding an alkali metal hydroxide such that the alkali metal hydroxide is in an amount of 1.00 to 1.10 mol per 1 mol of the sulfur source, and continuing the polymerization reaction in a homogeneous liquid phase condition.

The present invention is to provide a method of producing polyarylene sulfide that can produce polyarylene sulfide having a low halogen content simply and easily and at low cost. The method of producing polyarylene sulfide according to an embodiment of the present invention includes: a preparation step of preparing a mixture containing an organic amide solvent, a sulfur source, a dihalo aromatic compound, and an alkali metal hydroxide; a first-stage polymerization step of producing a prepolymer until a pH of a reaction system reaches a range of lower than 10 but 7 or higher by initiating a polymerization reaction by heating the mixture; and a second-stage polymerization step of continuing the polymerization reaction.

Provided is a method for manufacturing fine polyarylene sulfide (PAS) powder, in which impurities such as alkali metal salts and/or PAS oligomers are reduced while the wettability of the fine PAS powder in a fine PAS powder-containing solid is retained after solid-liquid separation of a separation liquid obtained by subjecting a dispersion liquid containing granular PAS to separation into granular PAS and a separation liquid; and a fine PAS powder. The method for manufacturing a fine PAS powder of the present invention includes: (a) separating granular PAS and a separation liquid from a dispersion liquid containing granular PAS, by solid-liquid separation using at least one screen that has an opening diameter of 75 to 180 &#x3bc;m; (b) performing solid-liquid separation of the separation liquid to obtain a fine PAS powder-containing solid; (c) heating the fine PAS powder-containing solid to reduce an amount of an organic solvent to obtain a wet cake; and (d) washing the wet cake using an aqueous solvent. The water content of the wet cake after heating is at least 30 wt. %.

Method for manufacturing fine polyarylene sulfide powder, and fine polyarylene sulfide powder

A branched polyarylene sulfide resin includes an &#x2014;S&#x2014; substituent group with a cleaved disulfide compound, which has a halogen content of 4,000 ppm or less, a melt viscosity as measured at a temperature of 330&#xb0; C. and a shear rate of 2 secof 1.0&#xd7;10to 50.0&#xd7;10Pa&#xb7;s, and a melt viscoelasticity tan &#x3b4; as measured at a temperature of 310&#xb0; C. and an angular velocity of 1 rad/sec of 0.1 to 0.6.

Branched polyarylene sulfide resin, method for manufacturing same and use as polymer modifier

A method of producing polyarylene sulfide (PAS) by subjecting a sulfur source and a dihalo aromatic compound (DHA) to polymerization reaction in an organic amide solvent under alkaline conditions, the method suppressing side reactions or the like and yielding PAS having a high degree of polymerization at a high yield is provided; and PAS having a high degree of polymerization are provided. A method of producing PAS, including: a preparation step of preparing a preparation mixture containing an organic amide solvent, a sulfur source, an alkali metal hydroxide, water, and DHA, and having a pH of 12.5 or higher; a first-stage polymerization step of heating the preparation mixture to 170&#xb0; C. or higher to initiate a polymerization reaction and continuing the polymerization reaction at 240 to 280&#xb0; C., thereby forming a prepolymer having a DHA conversion rate of 50% or greater (at this time, a temperature increasing rate from 220&#xb0; C. to 240&#xb0; C. is lower than a temperature increasing rate for 240&#xb0; C. or higher); and a second-stage polymerization step of adding, in the reaction system, an alkali metal hydroxide in an amount of 1 to 20 mol % per 1 mol of the sulfur source in the presence of a phase separation agent to continue the polymerization reaction at 245 to 290&#xb0; C. PAS having a melt viscosity (310&#xb0; C.; shear rate: 1216 sec) of 0.1 to 8000 Pa&#xb7;s produced by the method.

A granular polyarylene sulfide; (i) the granular polyarylene sulfide containing an &#x2014;S&#x2014; substituent at the terminal, the substituent being formed by cleavage of a disulfide compound; (ii) the granular polyarylene sulfide being an oversize fraction after sifting with a sieve having a mesh size of at least 38 &#x3bc;m; (iii) the granular polyarylene sulfide having a halogen content of at most 1,500 ppm; and (iv) the granular polyarylene sulfide being a granular polyarylene sulfide having a melt viscosity of 3 to 100 Pa&#xb7;s when measured under conditions at a temperature of 310&#xb0; C. and a shear rate of 1,200 sec. The granular polyarylene sulfide is well balanced in melt viscosity, halogen content, nitrogen content, thermal stability, and yield.

Granular polyarylene sulfide and process for manufacturing the same

The invention provides a production process of a poly(arylene sulfide) which contains a step of polymerizing a sulfur source and a dihalo-aromatic compound in an organic amide solvent, said polymerization step containing a phase-separation polymerization step that the polymerization reaction is continued in the presence of a phase separation agent in a phase-separated state, wherein a monohalo-organic compound is added in a proportion of 0.005 to 20 mol per 100 mol of the charged sulfur source into the polymerization reaction system at the time a conversion of the dihalo-aromatic compound has reached 80 to 99% after initiation of the polymerization reaction and before the liquid phase becomes the phase-separated state to be reacted with a formed polymer, and the liquid phase within the polymerization reaction system is then converted to the phase-separated state to continue the polymerization reaction.

Production process of poly(arylene sulfide) whose content of terminal halogen group has been reduced

The invention provides a production process of a poly(arylene sulfide), comprising a polymerization step of subjecting at least one sulfur source selected from the group consisting of alkali metal sulfides and alkali metal hydrosulfides and a dihalo-aromatic compound to a polymerization reaction in an organic amide solvent; a reaction step of adding a hydroxyl group-containing organic compound containing no bonded halogen atom in a proportion of 0.001 to 20 mol per 100 mol of the charged sulfur source into the polymerization reaction system containing the organic amide solvent and a formed polymer after the polymerization step to cause the formed polymer to react with the hydroxyl group-containing organic compound; and a collecting step of collecting a polymer from the polymerization reaction system after the reaction step, and the poly(arylene sulfide).

Poly(arylene sulfide) and production process thereof

A method for removing a liquid crystal alignment film from a liquid crystal cell substrate having the alignment film formed by coating a solution containing, as the main component, a polyamic acid having, as the main repeating units, a chemical structure of the following formula (1): ##STR1## wherein each of R.sub.1 and R.sub.2 is a hydrogen atom or a methyl group, R.sub.3 is a bivalent organic group constituting a diamine, and n is from 10 to 1,000, followed by baking, which method comprises irradiating said liquid crystal cell substrate with ultraviolet rays having wavelengths within a range of from 230 to 300 nm and then treating it with an aprotic highly polar organic solvent or an alkaline solvent.

Method for removing a liquid crystal alignment film

The present invention provides a method for forming an electrode, which comprises printing and drying on a glass substrate a thick film paste (a) having an inorganic powder containing an inorganic pigment as the main component, dispersed in an organic binder, then printing a thick film paste (b) having an inorganic powder containing a metal power and a glass powder as the main components, dispersed in an organic binder, to cover at least a part of said thick film paste (a), followed by baking at a temperature of from 400.degree. to 800.degree. C., and then removing (a) at the portion which is not covered by (b), to form an electrode which exhibits a desired color as observed from the side opposite to the printed side. According to the present invention, an electrode which exhibits a desired color as observed from the side of the glass substrate on which no electrode is formed, can be formed with excellent productivity.

Method for forming an electrode

An amine oxide is produced by oxidizing a tertiary amine having the formula ##STR1## wherein R.sub.1 and R.sub.2 respectively represent methyl or ethyl group; and R.sub.3 represent a C.sub.8 -C.sub.14 alkyl or alkenyl group in the presence of carbon dioxide and in the presence or absence of an improver selected from the group consisting of ethylenediaminetetraacetic acid, its salts, stanates, polyphosphates, salts of hydroxycaboxylic acid and salts of polycarboxylic acid.

Process for producing amineoxide

3,7-Dimethyl-2,6-octadienylamine derivatives are produced by reacting isoprene with a secondary amine in the presence of a catalyst prepared by reacting a secondary amine, a conjugated diene and/or a polycyclic aromatic compound, a lithium salt and sodium and/or potassium metal.

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Tokyo, Japan

Akihiro Konno