Process for making high-strength polylactic acid filament
US11111607B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 21, 2017 |
| Grant date | Sep 7, 2021 |
| Priority date | — |
| Expiry date | Jul 21, 2037 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD10B2401/063
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
The present invention relates to a process for making high-strength polylactic acid elongated object comprising the steps of making a solution of polylactic acid in a solvent at a concentration of 5 to 50 mass %; spinning the solution through a spinplate comprising at least 1 spinhole to form a fluid elongated object; cooling the fluid elongated object with a cooling medium to form a solvent-containing gel elongated object; removing at least partly the solvent from the gel elongated object to form a solid elongated object; and drawing the elongated object while applying a draw ratio of at least 2, to form a high strength PLA elongated object, characterized in that the cooling medium has a temperature Tq of less than 0° C. The present invention also relates to gel-spun elongated objects comprising PLA with an IV in the range of 4-40 dl/g, and having a tenacity in N/tex such that Ten≥0.146*IV, as well as gel-spun elongated object having a tenacity and a filament titer in tex (t) such that Ten≥1.40*t −0.3. The invention also relates to articles containing said gel-spun elongated objects.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.