Preparation and properties of film materials of poly(aryl ether ketone)-based phthalonitrile resins

Abstract

A series of poly(aryl ether ketone) polymers (m-PAEK-CN) containing phthalonitrile were synthesized by a direct solution polycondensation and characterized by Fouriertransform infrared spectroscopy and hydrogen nuclear magnetic resonance. Thermal crosslinking of m-PAEK-CN, catalyzed by p-BAPS, was then performed via heating their films up to 350 o C. Dynamic rheology results showed that the rate of diamine-catalyzed crosslink reaction could be easily controlled by varying the content of cyano groups in the polymer. The uncured synthesized polymers had good solubility, whereas the cured ones became insoluble in common organic solvents. Spectra measurement demonstrated the trimerization reaction of terminal cyano groups to form triazine rings. The resulting cured samples had higher glass transition temperatures, better thermal, and thermo-oxidative stability with high char yield than the uncured ones. Gel content measurements demonstrated that the cured polymers had high crosslinking density with significantly high gel content over 96.0%. Thermal mechanical analysis indicated that the cured phthalonitrile resins possessed excellent thermal mechanical properties and dimensional stability at increased temperatures. The tensile modulus and strength of the cured m-PAEK-CN increased up to 2101-2104 MPa and 96-100 MPa, respectively, which were about 21-23% and 32-56% higher than the uncured ones'. This kind of phthalonitrile resins may be used as a candidate for high-performance polymeric film materials.

Enhanced properties of phthalonitrile resins reinforced by novel phthalonitrile-terminated polyaryl ether nitrile containing fluorene group

“…In order to solve these problems, two main strategies were reported these years. One was to synthesis novel phthalonitrile-terminated oligomers, [7][8][9][10][11][12][13][14][15] and better processability and toughness could be realized simultaneously. However, the improvement in toughness was typically introduced by flexible chains, and decreased thermal properties and modulus would be compromised.…”

Curing behaviors and properties of epoxy and self-catalyzed phthalonitrile with improved processability

“…[2][3][4] However, the requirement of high curing temperature (>300 C) for a long period of time limits their applications to some extent. [5][6][7] To solve this problem, several works have focused on the design and synthesis of monomers with active groups that could promote the curing of nitrile groups. For example, the amino and phenol groups have been successfully introduced into phthalonitrile.…”

Thermal and oxidative behavior of a tetraphenylsilane-containing phthalonitrile polymer

“…These values are higher than observed for other phthalonitrile systems (40–60 µm/(m °C)). 68,69 This difference may be due to increased free volume from the inclusion of C–Si linkages.…”