摘要:
Provided is a method for producing a molded product comprising a step for preparing a polymerizable composition for optical materials and a step for curing the polymerizable composition for optical materials to produce the molded product. The step for preparing the polymerizable composition for optical materials comprises a step for preparing a defined polythiol compound and a step for preparing the polymerizable composition for optical materials from the polythiol compound. The step for preparing the defined polythiol compound comprises reacting 2-mercaptoethanol with a defined epihalohydrin compound at a temperature of 10° C. to 50° C. to obtain a defined polyalcohol compound, reacting the polyalcohol compound with thiourea in the presence of hydrogen chloride to obtain an isothiuronium salt, hydrolyzing the isothiuronium salt to obtain the polythiol compound, adding hydrochloric acid at a defined concentration to a solution of the polythiol compound, and washing the solution to purify the polythiol compound.
摘要:
The present invention relates to novel methods for preparing a polythiol compound for use in an optical material and polymerizable compositions including a polythiol compound prepared by the methods. According to the methods, a polythiol compound with uniform color, high purity and high quality can be prepared at reduced cost. The polymerizable compositions can be used to manufacture clear, transparent optical lenses with good heat resistance and excellent optical properties.
摘要:
The invention relates to a halide-containing alkali tungstate catalyst for the synthesis of alkylmercaptans from alkanols and hydrogen sulfide, and to a process for the preparation of this catalyst.
摘要:
The present invention relates to a process for continuously preparing methyl mercaptan from hydrogen sulphide and methanol in a direct connection with the preparation of hydrogen sulphide.
摘要:
The invention relates to a catalyst containing alkali tungstate for the synthesis of alkylmercaptanes from alkanols and hydrogen sulphide, in addition to a method for the production of said catalyst, wherein the molar ratio of alkali to tungstan is
摘要:
The invention relates to a catalyst containing alkali tungstate for the synthesis of alkylmercaptanes from alkanols and hydrogen sulphide, in addition to a method for the production of said catalyst, wherein the molar ratio of alkali to tungstan is
摘要:
The invention relates to an oxidic catalyst containing cesium and tungsten for the synthesis of alkyl mercaptans from alkanols and hydrogen sulfide, and to a process for the production of this catalyst, wherein the molar ratio of cesium to tungsten is
摘要:
The invention relates to a device for carrying out exothermal chemical reactions wherein a gas phase is guided across a fixed bed and allowed to react. Said device comprises a housing and an exchangeable unit wherein the reaction takes place.
摘要:
A process for continuously preparing methyl mercaptan by reacting a reactant mixture which contains a dialkyl sulphide and a dialkyl polysulphide with hydrogen sulphide to give methyl mercaptan.