Modified Crystallization in PET/PPS Bicomponent Fibers Revealed by Small-Angle and Wide-Angle X-ray Scattering

Abstract

We present a small-angle X-ray scattering (SAXS) and wide-angle X-ray scattering (WAXS) characterization of the semicrystalline structure of homo- and heterobicomponent core–sheath fibers melt-spun from poly(ethylene terephthalate) (PET) and poly(phenylene sulfide) (PPS). The two-dimensional SAXS/WAXS patterns of the various bicomponent fibers are found to reflect the mutual influence of the components on their thermal profiles along the spinline, leading to modified crystallization of the PET component and a larger strain rate in the PPS component. The predominant scattering features in the SAXS patterns are four-point reflections, an intense equatorial streak, and a central anisotropic diffuse scattering. The four-point reflections are attributed to tilted crystalline lamellar stacks of PET. The lamellar stack dimensions and the orientation of their lamellar surfaces are determined. We find that the heterobicomponent arrangement can promote the formation of equally spaced and uniformly sized crystallites in the PET phase and highly oriented crystallites in the PPS phase.

Hybrid Bulk Heterojunction Solar Cells Based on the Cooperative Interaction of Liquid Crystals within Quantum Dots and Diblock Copolymers

“…As shown in the inset of Figure 5, there were more outer rings appearing and a stronger reflection intensity in P3HT 44 -b-PTcbp 5 and P3HT 44 -b-PTcbp 7 , especially for P3HT 44 -b-PTcbp 5 , compared with pristine P3HT, which might be indicative of the better nanoscale crystallization of the P3HT 44 -b-PTcbp 5 block copolymer. 51 Furthermore, the 1D SAXS results were also included, where the P3HT, P3HT 44 -bPTcbp 5 , and P3HT 44 -b-PTcbp 7 films were measured at q ≈ 3.97, 3.89, and 3.79 nm −1 , and the peak was correlative with intermolecular interactions, which would directly affect the transmission of the electron hole, and related to the optical and charge-transport properties in this electronic device. 52 There existed a slight blue shift in P3HT 44 -b-PTcbp 7 (3.79 nm −1 ) and P3HT 44 -b-PTcbp 5 (3.89 nm −1 ) compared with pristine P3HT (3.97 nm −1 ), demonstrating that cyanobiphenyl side-chain mesogens would affect intermolecular π−π-stacking interactions and increase the distance between molecule chains among the thiophene rings.…”

“…To gain further insight into the differences in the packing arrangements of the polymers, bulk SAXS of P3HT, P3HT 44 - b -PTcbp 5 , and P3HT 44 - b -PTcbp 7 under DCB solvent annealing treatments for 12 h was processed. As shown in the inset of Figure , there were more outer rings appearing and a stronger reflection intensity in P3HT 44 - b -PTcbp 5 and P3HT 44 - b -PTcbp 7 , especially for P3HT 44 - b -PTcbp 5 , compared with pristine P3HT, which might be indicative of the better nanoscale crystallization of the P3HT 44 - b -PTcbp 5 block copolymer . Furthermore, the 1D SAXS results were also included, where the P3HT, P3HT 44 - b -PTcbp 5 , and P3HT 44 - b -PTcbp 7 films were measured at q ≈ 3.97, 3.89, and 3.79 nm –1 , and the peak was correlative with intermolecular interactions, which would directly affect the transmission of the electron hole, and related to the optical and charge-transport properties in this electronic device .…”

Numerical Simulation of the Non-Isothermal Co-Extrusion Fiber Spinning with Flow-Induced Crystallization

“…Many economic and technical advantages have been found in co-extrusion, it has gained wide recognition a polymer processing technique capable of achieving unique product performance, by combining the properties of different materials at lower cost Hufenus et al (2012), Perret et al(2013), Reifler et al (2014). Modeling and simulation of co-extrusion process require simultaneous consideration of constitutive and mass, momentum and energy conservation equations.…”

Melt-spun polymer fibers with liquid core exhibit enhanced mechanical damping

“…Considering the range of possibilities offered by bicomponent fibers -the two components usually being synthetic polymers -their overall mechanical performance is ultimately limited by the polymer properties [7,8]. For instance, in the case of a core-sheath arrangement, the core polymer may provide the desired mechanical characteristics, whereas the sheath polymer adds other specific functionality [9,10].…”