Bio-based poly(trimethylene terephthalate)/polyamide 56 blend fibers via melt spinning: Preparation, structure, and properties

Melt-spun poly(trimethylene terephthalate) (PTT) and polyamide 56 (PA56) fibers are generally prepared individually. Herein, inspired by the complementary properties of these two materials, PTT/PA56 blend fibers were prepared by two-step melt spinning and drawing processes. The regularity of crystalline regions, overall orientation in crystalline and amorphous regions, and dimensional stability under hot and humid conditions can be improved by increasing drawing temperature. The most suitable drawing temperature is 90 degrees C, at which 4-fold drawn PTT and PA56 fibers show tenacity of 2.94 and 3.54 cN/dtex, respectively. An increase in draw ratio leads to increase in the order of crystal regions and overall orientation in crystalline and amorphous phases. Interestingly, increasing dispersed phase content from 0 to 10 wt% is conducive to the increase in tenacity of samples. The PTT/PA56 (10/90) blend fiber suggests the maximum tenacity value, and tenacity of 4-fold drawn fiber is 4.02 cN/dtex. As PA56 content increases, dimensional stability of samples under dry conditions increases. Comprehensive analysis demonstrates that the PTT/PA56 (10/90) blend fiber achieves the best combination of tensile properties and dimensional stability. The prepared PTT/PA56 blend fibers are potentially competitive in the fields of fibers, garment, and decoration due to their satisfactory comprehensive performances. 90 degrees C is considered as the most suitable drawing temperature for PTT and PA56 fibers. At this drawing temperature, the tenacity of PTT or PA56 matrix fibers can be improved by adding low content of another polymer. Among these blend fibers, PTT/PA56 (10/90) blend fiber achieves the best combination of tensile properties and dimensional stability. image