Hailong Tang

Flexible magnetic copolymer films with high decomposition temperature and stable dielectric properties

Abstract Two novel kinds of flexible magnetic copolymer films were prepared via copolymerization using magnetic ferrocenyl prepolymer (MFP) and poly(arylene ether nitrile)s with bisphthalonitrile functional group. Two types of poly(arylene ether nitrile)s with bisphthalonitrile functional group were used and two series of flexible magnetic copolymer film with different structure were obtained. The magnetic properties of copolymer films indicated that the films were soft magnetic. Moreover, it was also concluded that the magnetic properties of magnetic films prepared from phthalonitrile terminated poly(arylene ether nitrile)s were higher than that of magnetic films prepared from poly(arylene ether nitrile)s with pendant phthalonitriles at the same content of MFP. The results of thermogravimetry showed that the all of the copolymer films possessed high decomposition temperature. Like the magnetism, the dielectric constant and dielectric loss of films obtained from phthalonitrile terminated poly(arylene ether nitrile)s were also higher than that of films obtained from poly(arylene ether nitrile)s with pendant phthalonitriles.

Effect of polyarylene ether nitrile on the curing behaviors and properties of bisphthalonitrile

Abstract The 2,2-bis[4-(3,4)-dicyanophenoxy phenyl]propane (BAPh)/polyarylene ether nitrile (PEN-OH) prepolymers and polymers were prepared by heat polymerization. Firstly, BAPh/PEN-OH systems were characterized using differential scanning calorimetry, dynamic rheological analysis, and thermal gravimetric analysis. The results revealed that the polymerization reaction can be controlled by various concentrations of PEN-OH and postcuring temperatures, and BAPh/PEN-OH prepolymers had low curing temperatures (229.3–300.4°C), large processing windows (∼106.5°C) with low melt viscosities, and excellent thermal stabilities. Then, the polymerization reaction and surface structures of BAPh/PEN-OH systems were investigated using Fourier transform infrared and scanning electron microscopy, respectively. The interpenetrating polymer networks were found in BAPh/PEN-OH polymers, suggesting that the addition of PEN-OH can not only promote the curing behaviors of BAPh but also increase the toughness of the polymers. The flexure strength and modulus of BAPh/PEN-OH polymers increased with the introduction of PEN-OH. The dielectric properties of BAPh/PEN-OH polymers were investigated, which had little dependence on the frequency. BAPh/PEN-OH systems can be used as a good candidate for high-performance polymeric materials.