PROCESS FOR PRODUCING POLYAMIDE,申请号KR20090046471-传众专利搜索

PROCESS FOR PRODUCING POLYAMIDE

申请公布号：KR20090124958(A)

申请号：KR20090046471

申请日期：2009.05.27

申请公布日期：2009.12.03

申请人：

MITSUBISHI GAS CHEMICAL COMPANY, INC.

发明人：KIKUCHI MINORU;SHINOHARA KATSUMI;KUROSE HIDEYUKI;KANDA TOMOMICHI

分类号：C08G69/32;C08G69/00;C08G69/26;C08G69/28

主分类号：C08G69/32

摘要：PURPOSE: A process for producing polyamide is provided to increase the productivity of polyamide per unit volume using direct polycondensation, to shorten reaction time, to control the degree of polymerization, and to obtain homogenized and good polyamide. CONSTITUTION: A process for producing a polyamide through direct polycondensation of a diamine component, which contains at least 70 mol% of a xylylenediamine containing at least 20 mol% of paraxylylenediamine, and a dicarboxylic acid component, substantially in the absence of a solvent and using a batch reactor equipped with a partial condenser; the process comprising the following steps: (i) a step of feeding the dicarboxylic acid component into the reactor, and then pressurizing the reactor to increase the inner pressure to a pressure of at least 0.1 MPaG, (ii) a step of continuously or intermittently adding the diamine component to the dicarboxylic acid component while the pressure inside the reactor is kept at 0.1 MPaG or more and while the reaction system is kept in a uniform flow state as a whole, (iii) after the addition of the diamine component, a step of lowering the pressure inside the reactor to atmospheric pressure or less at a pressure-lowering speed of from 0.1 to 1.0 MPa/hr.