Crystallinity of poly(arylene ether nitrile) copolymers containing hydroquinone and bisphenol A segments

Abstract

The hydroquinone (HQ) and bisphenol A (BPA) type poly(arylene ether nitrile) (PEN) (HQ/BPA-PEN) were synthesized through nucleophilic aromatic substitution polymerization from HQ, BPA, and 2,6-dichlorobenzonitrile (DCBN). The prepared copolymers were characterized by intrinsic viscosity, Fourier transform infrared (FTIR), and dynamic rheological analysis. The properties of resultant copolymers were studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and mechanical testing. The results showed that the PEN copolymers exhibited crystallization performance with excellent thermal and mechanical properties. HQ/BPA-PEN10 was made into films by solution-casting process and then were treated at different temperatures (200, 260, 280, 300, 310, and 320 8C) for different times (1, 2, 3, 4, and 5 h) to investigate the crystallinity. Results showed that when isothermal treatment temperature is 310 8C and isothermal treating time is 4 h, HQ/BPA-PEN10 showed best properties. At this condition, the melting enthalpy, crystallinity, tensile strength, and elongation at break of the sample is 17.7 J/g, 14.11%, 132.9 MPa, and 6.1%, respectively.

Fabrication of BaTiO3-Loaded Graphene Nanosheets-Based Polyarylene Ether Nitrile Nanocomposites with Enhanced Dielectric and Crystallization Properties

“…Besides, it is clear that the dielectric constant of the BT@ZnPc-GO-2/PEN was slightly lower than that of BT@ZnPc-GO-1/PEN at the same content of the nanofillers, which was due to the increase in At the same time, the dielectric loss of the nanocomposites shows a similar trend to that of the dielectric constant in this work. It can be seen from Figure 7b that the dielectric loss slightly increased from 0.018 to 0.023 at 1 kHz with the BT@ZnPc-GO-1 contents increasing from 1% to 15%, which is mainly caused by the conductance loss [31]. More importantly, the dielectric loss of all nanocomposites was well controlled at a relatively low level (<0.025), which satisfied the practical application requirements of electronic components.…”

“…Moreover, the C1s spectrum of BT@ZnPc-GO can be quantitatively differentiated into four different carbon species located at 284.6, 285.8, 287.3 and 288.9 eV [25], which belong to the chemical bonds of the Furthermore, the the XRD patterns of GO, ZnPc, BT, BT@ZnPc and BT@ZnPc-GO are shown in Figure 5. As can be seen from the spectra of BT, BT@ZnPc and BT@ZnPc-GO that the diffraction patterns at 2θ = 22.2°, 31 Furthermore, the the XRD patterns of GO, ZnPc, BT, BT@ZnPc and BT@ZnPc-GO are shown in Figure 5. As can be seen from the spectra of BT, BT@ZnPc and BT@ZnPc-GO that the diffraction patterns at 2θ = 22.…”

“…In addition, the arrangement of macromolecules in the amorphous phase can also result in thickening of the original crystalline regions. However, as the processing temperature increases, more and more macromolecules in the amorphous phase rearrange to form new crystalline regions, resulting in an increase in new crystalline regions and an increase in Tml [31]. As shown in Figure 9, when the heat treatment temperature is further increased and approaches Tml, the macromolecules in the original crystalline region start to move, resulting in disintegration of the crystalline region.…”

Improving the thermal and mechanical properties of poly(arylene ether nitrile) films through blending high‐ and low‐molecular‐weight polymers

“…On the one hand, at the temperature of 280 °C, the crosslinking reaction hardly occurs; thereby, the LMW PEN‐Ph is acting as plasticizer. On the other hand, the presence of the crystals could make the T g increase . Thus, for the sample 2 # to sample 6 # , the T g will decrease because of the LMW PEN‐Ph plasticization effect, while increase because of the crystal enhancement effect.…”

“…Poly(arylene ether nitrile)‐phenyl (PEN‐Ph) as a kind of high‐performance engineering plastics is usually a linear polymer, and it is widely used in the commercial and academic fields due to its excellent performance such as outstanding chemical properties (radiation resistance, low flammability, and toxic gas emission), high thermal stability, superior mechanical properties as well as good molding workability . The PEN with different dihydric phenol structure (Figure ) possesses different properties.…”