No abstract

Sulfonated polyetheretherketone (SPEEK) was synthesized via a mono-substitution reaction of PEEK in concentrated sulphuric\ud acid and was blended with polypropylene (PP) in 2–10%w/w concentration to be used for the production of photoactive thermoplastic\ud products. SPEEK and SPEEK/PP blends were characterized using FTIR, DSC, TGA, NMR, rheology, SEM, and EPR. Under\ud UV-Vis irradiation, stable benzophenone ketyl (BPK) radicals were generated by hydrogen extraction from PP. By increasing the\ud amount of SPEEK in the polymer blend a linear increase in the BPK radicals was achieved according to the EPR data. DSC and TGA\ud tests indicated weaknesses in the thermal stability of SPEEK but according to the rheological tests this should not have a major effect\ud on processabililty. The optimal amount of SPEEK in the blend was obtained at 5%w/w. This concentration provided a good compromise\ud between radical concentration, material processability, and cost

New photocatalytic fibers made of sulfonated polyetheretherketone (SPEEK)/polypropylene (PP) are melt compounded\ud and melt spun, first on laboratory scale and then on a semi-industrial scale. Fiber spinnability is optimized and the fibers are characterized\ud using mechanical testing, electron paramagnetic resonance (EPR) spectroscopy, and scanning electron microscopy (SEM).\ud According to the results, the fiber spinnability remains at a good level up to 10 wt % SPEEK concentration. Optimal processing temperature\ud is 2008C due to the thermal degradation at higher temperatures. EPR measurements show good and long-lasting photoactivity\ud after the initial irradiation but also decay in the radical intensity during several irradiation cycles. Mechanical tenacity of the\ud SPEEK/PP 5 : 95 fiber is approximately 20% lower than for otherwise similar PP fiber. The fiber is a potential alternative to compete\ud against TiO2-based products but more research needs to be done to verify the real-life performance