Sdt q600

Measurement of the tensile property was carried out on a universal testing machine (CMT6000, SANS, Shenzhen, China) following the standard ASTMD 638. The testing speed was kept at 5 mm min⁻¹. The morphology of the fracture surfaces of specimens subjected to tensile measurement were gold-coated and analyzed with a field emission scanning electron microscopy (FE-SEM) (Hitachi SU8010, Japan) connected to an energy dispersive X-ray spectrometry (EDS) analyzer (Apollo 40 SDD). The morphology of a single nanofiber was analyzed with transmission electron microscopy (TEM) (Hitachi, HT7800, Japan). Thermogravimetric analysis (TGA) was performed from 100 to 800 °C at a heating rate of 20 °C min ⁻¹ under a nitrogen flow (with a Waters SDT Q600, USA). Dynamic mechanical analysis (DMA) for the films was carried out from 30 to 450 °C at a heating rate of 5 °C min⁻¹ under a nitrogen flow with a dynamic mechanical analyzer (TA Q-800, USA). The film was tested under the tensile mode at a frequency of 1 Hz. The thermal expansion along the plane (X–Y) direction of the film (15 mm long, 5 mm wide, and about 50 μm thickness) were measured at a heating rate of 5 °C min⁻¹ with a thermomechanical analyzer (TA, TMA-400Q) in a dry nitrogen atmosphere. The CTE values of the films were obtained over the temperature range of 50–250 °C by averaging three test results.