This project is a part of European commission collaborative Safeprotex project of Seventh Framework Programme to manufacture high protective clothing for complex emergency operations. The goal of this thesis is to manufacture polyetheretherketone, PEEK, fibers by melt spinning and modify them to provide antimicrobial, self-cleaning and antipollution properties.PEEK has excellent thermal and mechanical properties and good chemical resistance. The literature review clearly shows that PEEK should be easily spinnable. Melt spinning is a process where polymer is melted, normally by extruder or piston system. The system of TUT is based on Göttfert capillary rheometer which is a piston system. Melt material is pushed through a small hole after which it faces cold air and starts to cool down. Solidified fiber is drawn to a roll.PEEK modification is done by sulfonate groups that change the chemical structure so that functional properties are possible. Without modification the reaction does not happen. Reaction is based on benzophenone compounds that are excited by UV-light.During the experimental part DSC, TGA and rheological tests were made to characterize PEEK. The results of these tests confirm that PEEK has excellent thermal properties and it should be easily spinnable. Fiber spinning of virgin PEEK turned out to be easy and the best achieved fibers were less than 20 μm in diameter. Operating temperature and hole diameter turned out to be the most important parameters in our spinning system. TUT piston system, Göttfert capillary rheometer is not designed for fiber spinning which lead to a few problems most importantly variations in fiber thickness.PEEK modification was done by our Italian partner company Next Technology Tecnotessile. Modification provided wanted functional properties but it also made spinning more difficult, worsened thermal stability and made the fibers more brittle. Modified PEEK was mixed with virgin PEEK to avoid these problems. At best, 1.5 % of modified PEEK could be added to virgin PEEK and still be able to make fibers of it. /Kir11
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