Synthesis and characterization of polyimide thin films obtained by thermal evaporation and solid state reaction

Abstract

In this research polyimide films were prepared by physical vapor deposition (PVD), using solid state reaction of pyromellitic dianhydride (PMDA) and p-phenylene diamine (PDA) to form poly(amic acid) (PAA) films. The resultant films were converted to polyimide by thermal treatment, usually below 300 • C. For this study, a FT-IR spectrometer has been used to measure the effect of imidization temperature on the chemical structure of the vapor-deposited thin films of aromatic PI. When temperature increased, an increase in all absorption peaks was observed. This suggests that residual PAA monomers continued to be converted into PI. The surface topology of the PI films obtained at imidization temperatures of 150, 200, 250 • C for 1 hour was further examined by using AFM atomic force microscopy. It can be clearly seen that the surface became rougher with increasing imidization temperature. The thermal stability of polyimide was also studied by using thermogravimetric analysis (TGA).

Thermal and electrical properties of polyimide/PANI nanofiber composites prepared via in situ polymerization

“…3, the major step of weight loss for PI occurs above 550°C. This behavior agrees with the literature [11]. The T 0 occurs at 552°C, T 10 around 581°C, and T max of 615°C has been observed [11,12].…”

“…The increase in electrical conductivity of polyimide/PANI nanofiber composites may result from the increased chain ordering by annealing effect. Similar result has been reported reported by Al-Ajaj et al [11].…”

“…This behavior agrees with the literature [11]. The T 0 occurs at 552°C, T 10 around 581°C, and T max of 615°C has been observed [11,12]. In PI/PANI nanofiber composites, 5 wt.% addition of PANI nanofibers into PI matrix resulted in improved thermal properties (T 0 = 573°C, T 10 = 623°C, and T max = 678°C).…”

Rapid formation of polyimide nanofiber membranes via hot-press treatment and their performance as Li-ion battery separators

“…11,21,38 The PI membrane prepared by the hot-press treatment only showed one sharp weight loss at $575 C, completely overlapping with the third drop of the PAA membrane. 32,39,40 Additionally, the thermal shrinkage of the PI and PE membranes was compared aer the heat treatment in an oven (at three different temperatures) for 1 h (see the digital photos in Fig. 6 and S3 †).…”

Characterization of Multiblock (Segmented) Copolyurethane- Imides and Nanocomposites Based Thereof Using AFM, Nanotribology, and Nanoindentation Methods

“…For the creation of new-generation polymer materials based on multicomponent systems, it is necessary to study the morphology, mechanical behavior, and various properties of these systems in the submicron and nanoscale range. It is known that surface layers of polymer objects exhibit significant differences in properties as compared with bulk material and play a decisive role in various applications especially if they are used as films and coatings [1].…”