The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 14, 2017
Filed:
May. 05, 2011
Pim Gerard Anton Janssen, Echt, NL;
Ronald Ligthart, Echt, NL;
Pim Gerard Anton Janssen, Echt, NL;
Ronald Ligthart, Echt, NL;
DSM IP ASSETS B.V., Heerlen, NL;
Abstract
A process for preparation of a polyamide PA-4X containing monomer units of 1,4-diaminobutane and an aliphatic linear dicarboxylic acid X with at least 8 carbon atoms, which contains the following steps: 1) making a solution comprising a salt of 1,4-diaminobutane and the aliphatic linear dicarboxylic acid and water, at a temperature at which the salt dissolves; 2) concentrating the solution of the salt at a temperature above the crystallization temperature of the salt, at a pressure of at most 7 barA to a water content of between 0 and 30 wt % based on the total amount of solution, 3) producing a polymer from the solution obtained by step 2, while keeping the polymer in a melt and at a pressure of less than 18 barA, 4) depressurizing the polymer obtained at step 3 while keeping the polymer in the melt to further polymerize the polymer. In an preferred embodiment the aliphatic linear dicarboxylic acid is 1,10-decanedioic acid. Also claimed is a polyamide 410 having a viscosity number (VN) of at least 100 ml/gram.