Design and synthesis of a tribranched phenylethynyl‐terminated aryl ether compound and its use as a reactive diluent for PETI‐5

Abstract

In this study, a tribranched, phenylethynyl‐terminated aryl ether compound (Tri‐PE‐PAEK) was synthesized. This novel star‐shaped compound exhibits a good combination of properties, such as a low melting temperature (252 °C) and good solubility in aprotic solvents, as well as a low melt viscosity (0.1 P at 280 °C). All these advantages make it a good candidate material for modern processing techniques such as resin infusion and resin transfer molding, which are the most favorable methodologies for current economical manufacturing of polymer matrix/carbon fiber composites. Furthermore, after undergoing thermal curing to yield a network at 370 °C for 1 h, a cured sample exhibited an unexpectedly higher glass transition temperature (370 °C), storage modulus retention above the glass transition temperature, and good thermal stability. In addition, this compound can be used as a reactive diluent for phenylethynyl‐terminated imide oligomer, which has the molecular weight of 5000 g/mol (PETI‐5) to reduce its viscosity and lower the minimum temperature of the minimum viscosity. Meanwhile, the toughness of a cured blended resin can be greatly increased with the addition of just 10% Tri‐PE‐PAEK to PETI‐5. Further loading levels of Tri‐PE‐PAEK in the blending would lead to a higher storage modulus and a higher mechanical strength without compromising the thermal stability. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4844–4854, 2007

HighTgand Thermo‐Oxidatively Stable Thermosetting Polyimides Derived from a Carborane‐Containing Diamine

“…In the field of advanced polymers, thermosetting polyimides (PIs) occupy a preponderant position due to their excellent chemical stability, thermal and mechanical properties . Thermosetting PIs are being designed for aerospace applications to meet the expectation of performance and durability in high temperature oxidative environments . It is well known that, the glass transition temperature ( T g ) is a fundamental characteristic of any thermoset, and polymers with higher T g are actively sought for a variety of high‐performance applications .…”

“…[1][2][3][4][5][6] Thermosetting PIs are being designed for aerospace applications to meet the expectation of performance and durability in high temperature oxidative environments. [7][8][9][10][11][12][13] It is well known that, the glass transition temperature (T g ) is a fundamental characteristic of any thermoset, and polymers with higher T g are actively sought for a variety of high-performance applications. [14] However, the conventional PIs, due to the influence of bond energy of C, H, O, and N, are susceptible to decomposition at elevated temperatures in oxidative environments, and have T g which are usually lower than 450 °C.…”

Synthesis and characterization of branched phenylethynyl-terminated polyimides

“…Aromatic polyimides from the phenylethynyl-terminated imide oligomers (PETIs) have demonstrated favorable processability, superior thermal and mechanical properties [19][20][21]. Ever since 1980s, more than 100 kinds of PETIs have been successfully fabricated.…”

Synthesis of transparent and thermally stable polycyanurates and their thermal rearrangement

“…Thus, a postcuring procedure is necessary for the film to prevent each layer from mixing by applying the crosslinking reactions. For example, poly(arylether‐ketone)s with ethynyl as crosslinkable groups were cured at a very high temperature . Poly(arylether‐ketone)s containing carboxylic acids were used to react with poly(vinyl alcohol) or bisphenols to prepare crosslinked polymers .…”