Polysiloxanes and Silanes with Various Functional Groups-New Compounds for Flax Fibers' Modification.

There is an increasing desire to use natural products that will be both effective and biodegradable. The aim of this work is to investigate the effect of modifying flax fibers with silicon compounds (silanes and polysiloxanes), as well as examining the effect of the mercerization process on their properties. Two types of polysiloxanes have been synthesized and confirmed by infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (NMR). Scanning electron microscopy (SEM), FTIR, thermogravimetry analysis (TGA) and pyrolysis-combustion flow calorimetry (PCFC) tests of the fibers were performed. On the SEM pictures, flax fibers purified and covered with silanes were visible after treatment. FTIR analysis showed stable bonds between the fibers and the silicon compounds. Promising results of thermal stability were obtained. It was also found that modification had a positive effect on the flammability. The conducted research showed that the use of such modifications, in the context of using flax fibers for composites, can yield very good results.

Multifunctional Cotton Fabrics Obtained by Modification with Silanes Containing Esters of Phosphoric Acid as Substituents.

The development of novel flame retardants for cotton textiles that form a stable layer on textile fiber is of high economical and practical relevance. A novel flame retardant fluorinated phosphoric acid esters modified silicone resins for cotton modification were synthesized. The investigated phosphoric acid esters based compounds were substituted by a fluorinated chain or ring, and alkoxysilyl groups. The presence of alkoxysilyl groups allowed the formation of bonds with cellulose, while derivatives of phosphoric esters reduced the flammability of fabrics. Additionally, the presence of fluoride in their structures affected the hydrophobic properties. Cotton fabrics were modified in a simple one-step process by dip-coating method. The flame retardant properties of modified textiles were examined by performing microcalorimetric analysis, thermogravimetry analysis, and measuring oxygen index. The hydrophobicity was evaluated by measuring the water contact angle. The modified fabrics were characterized by SEM-EDS (Scanning Electron Microscopy with Energy Dispersive Spectroscopy) analysis and surface morphology. As a result of the tests, multifunctional fabrics were obtained.