Abstract: Described is an apparatus for the purpose of drying or solid phase polymerization of Polymer particles by batchwise heating the same in an atmosphere of inert gas or under reduced pressure. More particularly, described is batchwise heating apparatus which is capable of efficient production by preventing an objective product from being contaminated with foreign matters accompanying wear of a sealing packing.

Abstract: In the production method of polyamide of the present invention, the mole balance at a set point during melt polymerization is estimated from a pre-established equation for calculating the mole balance during melt polymerization from a melt viscosity. On the basis of the estimated mole balance, the subsequent conditions of melt polymerization of a batch and the polymerization conditions of the next and subsequent batches are determined. In addition, the mole balance, molecular weight and relative viscosity of melt-polymerized polyamide are estimated from pre-established equations each for respectively calculating the mole balance, molecular weight and relative viscosity at the end point of melt polymerization from the melt viscosity. The conditions for solid phase-polymerizing the melt-polymerized polyamide are determined on the basis of estimated values.

Abstract: A method of stably producing glycidyl 2-hydroxyisobutyrate at high purity and high yield is provided. A reactive diluent is provided for an epoxy resin including the above-mentioned glycidyl 2-hydroxyisobutyrate, and an epoxy resin composition.

Abstract: A method of stably producing glycidyl 2-hydroxyisobutyrate at high purity and high yield is provided. A reactive diluent is provided for an epoxy resin including the above-mentioned glycidyl 2-hydroxyisobutyrate, and an epoxy resin composition.

Abstract: In the production method of polyamide of the present invention, the mole balance at a set point during melt polymerization is estimated from a pre-established equation for calculating the mole balance during melt polymerization from a melt viscosity. On the basis of the estimated mole balance, the subsequent conditions of melt polymerization of a batch and the polymerization conditions of the next and subsequent batches are determined. In addition, the mole balance, molecular weight and relative viscosity of melt-polymerized polyamide are estimated from pre-established equations each for respectively calculating the mole balance, molecular weight and relative viscosity at the end point of melt polymerization from the melt viscosity. The conditions for solid phase-polymerizing the melt-polymerized polyamide are determined on the basis of estimated values.

Abstract: The present invention provides an apparatus for the purpose of drying or solid phase polymerization of Polymer particles by batchwise heating the same in an atmosphere of inert gas or under reduced pressure. More particularly, it pertains to batchwise heating apparatus which is capable of efficient production by preventing an objective product from being contaminated with foreign matters accompanying wear of a sealing packing.

Abstract: The polyamide resin of the present invention is produced by the polycondensation of a dicarboxylic acid component and a diamine component containing xylylenediamine and bisaminomethylcyclohexane in a total amount of 70 mol % or higher. The polyamide resin contains impurities having a boiling point of from 150 to 300° C. at ordinary pressure and a solubility parameter of from 8 to 16 in a total amount of 0.3% by weight or lower based on the weight of the polyamide resin. The polyamide resin is free from various inconveniences due to inclusion of the impurities, and suitably used in applications for molding materials, bottles, sheets, films and fibers.

Abstract: In the process for producing polyamide of the present invention, a diamine and a dicarboxylic acid are melt-polycondensed in a batch-wise fist polymerizer in the absence of a solvent to produce a middle-stage polyamide. The diamine has a boiling point higher than a melting point of the middle-stage polyamide being produced under inner pressures of the first polymerizer. The middle-stage polyamide is fed into a continuous second polymerizer while controlling the change of relative viscosity within ±0.2, and further polycondensed there to produce the objective polyamide. With such a process, the change of polymerization degree of the middle-stage polyamide during the switching of the polymerization step from a batch-wise manner to a continuous manner is avoided, thereby preventing the variation in quality of the final product.

Abstract: In the process of the present invention, a recovered polyamide is used as a part of the raw materials for producing polyamide. By carrying out the polycondensation under a condition such that the recovered polyamide is dissolved in the reaction system during the polycondensation, the properties of the polyamide being produced are not deteriorated as compared with those of polyamide which is produced without using the recovered polyamide. By changing the addition amount of the recovered polyamide, the crystallization speed of the resultant polyamide is controlled or increased as compared when produced without using the recovered polyamide.

Abstract: The polyamide resin of the present invention is produced by the polycondensation of a dicarboxylic acid component and a diamine component containing xylylenediamine and bisaminomethylcyclohexane in a total amount of 70 mol % or higher. The polyamide resin contains impurities having a boiling point of from 150 to 300° C. at ordinary pressure and a solubility parameter of from 8 to 16 in a total amount of 0.3% by weight or lower based on the weight of the polyamide resin. The polyamide resin is free from various inconveniences due to inclusion of the impurities, and suitably used in applications for molding materials, bottles, sheets, films and fibers.

Abstract: In the process for producing polyamide of the present invention, a diamine and a dicarboxylic acid are melt-polycondensed in a batch-wise fist polymerizer in the absence of a solvent to produce a middle-stage polyamide. The diamine has a boiling point higher than a melting point of the middle-stage polyamide being produced under inner pressures of the first polymerizer. The middle-stage polyamide is fed into a continuous second polymerizer while controlling the change of relative viscosity within ±0.2, and further polycondensed there to produce the objective polyamide. With such a process, the change of polymerization degree of the middle-stage polyamide during the switching of the polymerization step from a batch-wise manner to a continuous manner is avoided, thereby preventing the variation in quality of the final product.

Abstract: In the process of the present invention, a recovered polyamide is used as a part of the raw materials for producing polyamide. By carrying out the polycondensation under a condition such that the recovered polyamide is dissolved in the reaction system during the polycondensation, the properties of the polyamide being produced are not deteriorated as compared with those of polyamide which is produced without using the recovered polyamide. By changing the addition amount of the recovered polyamide, the crystallization speed of the resultant polyamide is controlled or increased as compared when produced without using the recovered polyamide.

Abstract: There are provided a heat-aging-resistant polyamide resin composition comprising (C) a polyamide containing 10 to 100% by weight of (A) a polyamide obtained by polymerizing a monomer containing 70 mole % or more of m-xylylenediamine as a diamine component and a monomer containing 70 mole % or more of adipic acid as a dicarboxylic acid component and 90 to 0% by weight of (B) other polyamide, (D) a copper compound in an amount of 0.001 to 0.1 part by weight per 100 parts by weight of the polyamide (C), (E) a halide of a Group 1 or Group 2 metal of the Periodic Table of the Elements, an ammonium halide, or an organohalide in an amount of 0.005 to 1 part by weight per 100 parts by weight of the polyamide (C), at least one selected from among (F) hindered phenols and (G) hindered amines with the amount of each of the hindered phenols (F) and the hindered amines (G) being 0.05 to 3 parts by weight per 100 parts by weight of the polyamide (C), and (H) an organophosphorus compound in an amount of 0.

Abstract: An oriented polyamide fiber which comprises at least 20% by weight of a crystalline polyamide copolymer (A) produced by polymerizing at least one diamine monomer containing at least 70 mol % m-xylylenediamine and at least one dicarboxylic acid monomer containing at least 70 mol % adipic acid. The oriented polyamide fiber having a Young's modulus of at least 400 kgf/mm.sup.2, a loop strength of at least 4.5 gf/D, a knot tensile strength of at least 3.5 gf/D and a roundness of from 97 to 100%. A process for producing the oriented polyamide fiber which comprises melting a polyamide resin comprising the crystalline polyamide copolymer (A); spinning the molten resin through a spinneret; pulling the spun product into a coolant bath disposed beneath the face of the spinneret to produce non-oriented fiber to a draw ratio of 2.5 to 8.0 at a temperature not lower than the Tg of the polyamide and not higher than the melting point of the polyamide, wherein the draft ratio is 1.0 to 3.

Abstract: There are disclosed oriented polyamide fiber which comprises at least 20% by weight of a crystalline polyamide or a copolymerized polyamide each produced by polymerizing a monomer containing m-xylylenediamine as a diamine component and adipic acid as a dicarboxylic acid component each in an amount of at least 70 mol % (A) and which has a Young's modulus of at least 400 kgf/mm.sup.2, a loop strength of at least 4.5 gf/D, a knot tensile strength of at least 3.5 gf/D and a roundness of from 97 to 100%; and a process for producing oriented polyamide fiber which comprises the steps of melting a polyamide resin comprising at least 20% by weight of the above crystalline polyamide or copolymerized polyamide (A); spinning the molten resin through a spinneret; pulling the spun product into a coolant bath placed beneath the face of the spinneret to produce non-oriented yarn; and thereafter orienting the non-oriented yarn to a draw ratio of from 2.5. to 8.