Tga dsc instrument

The synthesized materials were analyzed by X-ray diffraction using a Phillips PW1800 instrument system in θ–2θ geometry working in Bragg–Brentano mode using Cu Kα radiation (λ = 1.541 Å). An AntonPaar1200 cell equipped with a capillary stage was used for the in situ X-ray diffraction (XRD) heating experiments. Scanning electron microscopy (SEM) images were recorded using an XL30-SEM instrument operated at 10 kV. The samples were sprinkled over carbon tape, attached to Al stubs and then coated with a 30 nm layer of carbon to prevent charging. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were performed using a Mettler TGA–DSC instrument with a heating rate of 5°C min⁻¹ and a temperature limit of 550°C. One-dimensional ¹³C-NMR was measured using a Brukner 400 MHz instrument in D₂O, and for the solid-state ¹³C CP-MAS NMR, the spectra were acquired at 9.4 T using a spinning speed of nR = 10.0 kHz and a CP contact time of 5.0 ms. For the ²⁷Al and ²⁹Si MAS NMR spectra, a Bruker Avance II HD 400 MHz spectrometer was used. ²⁷Al MAS NMR spectra were recorded at spinning rate of 20 kHz on a Bruker 3.2 mm probe, using a flip angle of π/12 and a recycle delay of 1 s. ²⁹Si MAS NMR spectra were recorded at a spinning rate of 5 kHz on a Bruker 4 mm probe using a flip angle of 60° and a recycle delay of 60 s.

Differential scanning calorimetry (DSC, NETZSCH STA 449C) measurements were used to characterize the change in the thermal properties of the polymers at a heating rate of 10 °C/min. The thermal stability of the polyimide films was performed by thermal gravimetric analysis (TGA) under N₂ environment on a Mettler-Toledo TGA/DSC instrument at a heating rate of 10 °C/min.