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:
Jul. 05, 1988
Filed:
Nov. 10, 1986
Vladimir Kubanek, Prague, CS;
Zdenek Sterbacek, Ceske Budejovice, CS;
Jaroslav Kralicek, Prague, CS;
Ceskoslovenska akademie ved, , CS;
Abstract
The invention pertains to a method for postpolymerization of granules of polyamide based on .epsilon.-caprolactam and formed by the anionic polymerization in melt and solves the problem of decreasing the content of low-molecular-weight substances in granules. At the same time, the invention pertains to an arrangement of equipment for performing the postpolymerization. The objective of the invention is a method for the continuous postpolymerization of polyamide based on .epsilon.-caprolactam and formed by the anionic polymerization in melt, wherein the postpolymerization proceeds in two stages, while the granules are heated in the first stage to the required temperature of postpolymerization 160.degree. to 200.degree. C. for 5 to 30 minutes during their vertical transport and allowed at this temperature for 2 to 6 hours in the second stage without mechanical intervention at their gravitation transport which is assisted by vibrations or a reservoir. An equipment for performing the method according to the invention which is formed by a two-stage unit consisting of a vertical vibration conveyer-heat exchanger and a reservoir, while the heat exchanger is provided with a heating jacket, a hopper in the lower part, and a heated overfall in the upper part, through which it is connected with the reservoir, while the reservoir is furnished outside with a jacket and a vibrator, inside with two plate heat-exchangers with the heating controlled by a temperature sensor, and in the lower part with a turnstile.