Effect of quaternary ammonium compound preparations on poly(ethylene terephthalate) fibre

Preparations based on quaternary ammonium salts (QAC) can have a plasticizing effect on PET and can also play the role of a catalyst of hydrolysis of cyclic oligomers - both complete and partial. The intensive migration of oligomers to the surface of the polymer material is due to their plasticizing effect, and the oligomer content in the internal regions of the fibre decreases, but the content on the surface increases as a result. Fulfilling the function of a catalyst of hydrolysis of cyclic oligomers, the QAC preparations cause these oligomers to be removed from the surface of the fibre materials by enhancing formation of soluble oligomers in linear form and TPA. As a function of the type of preparation, both the first and the second functions can be executed or they can be combined. By correctly selecting the QAC preparations, it is thus possible to regulate the oligomer content in the inner regions and on the surface of a fibre material.