In-situ X-ray analysis for process development of cellulose textile fibers from sustainable raw materials

Purpose and goal:

The increasing demand for textiles is a growing environmental problem and there is a great need to replace cotton and synthetic fibers with more sustainable alternatives. Tree to Textile has developed a new cellulose-based textile fiber, produced via a sustainable process. TTT is also looking at alternative cellulosic raw materials from agricultural waste and recycled material.

The raw material has a large influence on the initial dissolution and understanding the process is crucial. With synchrotron-based SAXS/WAXS, we were able to follow the dissolution in real time. Expected results and effects:

After compiling all the data, it was found that with SAXS it was possible to follow in real time the initial swelling, subsequent dissolution and the final state of the various masses. With WAXS, we could simultaneously observe the decomposition of crystalline cellulose. The combination of these techniques has not been presented before and contributes to new knowledge of how cellulose dissolution proceeds.

The results will be published and also applied in TTT´s ongoing scale-up. The knowledge is of great value to meet needs regarding process development. Approach and implementation:

A three-day beam time was granted on P62 at PETRA III (DESY, Hamburg) and the experiments were successfully carried out. Cellulose from different sources was mixed with different types of solvents in capillaries and mounted in a temperature-controlled sample holder. The samples were cooled in a temperature cycle of +25 °C to -30 °C and up to +25 °C again at a rate of 2 °C/min.

To minimize radiation damage, an absorbent was placed between the X-ray beam and the sample. The generated data of the resolution was analyzed and modeled afterwards.