The percentage of rigid chain length, (PRCL), a new concept for predicting glass transition temperatures and melting points of poly(aryl ether ketones) and poly(aryl ether sulfones)

Two new monomers were prepared by the reaction of 2-allylphenol and 4,4′-biphenyldicarbonyl chloride under different reaction conditions. The monomers were characterized by Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The curing processes of N, N-4,4′-bismaleimidodiphenylmethyene with 4,4′-bis(2-allylphenyl) biphenyldicarbonylate (BABC) and 4,4′-bis(2-propenylphenyl benzoate) ether (BPBE) were studied by rheological analysis and differential scanning calorimetry. Melting points of two monomers, BABC and BPBE, are 64°C and 121°C, respectively. The ABMI [4,4′-bis(2-allylphenyl)biphenyl bismaleimide] and PBMI [4,4′-bis(2-propenylphenyl)biphenyl bismaleimide] resins showed exothermic peaks at 233°C and 204°C, respectively. The measured melting points are significantly lower than that of the traditional bismaleimide resin which is modified by allyl bisphenol A. Dynamic mechanical analysis of the materials showed glass transition temperatures of ABMI and PBMI to be in the range of 213–258°C and 302–339°C, respectively. Thermogravimetric analysis of the cured resins showed 5% weight loss for ABMI and PMBI at 437°C and 428°C, along with char residues of 35.6–39.5%, respectively, at 800°C under nitrogen atmosphere. Furthermore, dielectric constants of propenyl-modified resins were lower (2.46–3.10) with dissipation factors of 0.0034–0.0036, compared with those of allyl bisphenol A resins.

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Synthesis, characterization and thermal crosslinking behavior of new poly(aryl ether sulfone)s based on naphthalene isomers

e-Polymers ◽

10.1515/epoly.2008.8.1.946 ◽

2008 ◽

Vol 8 (1) ◽

Author(s):

Zhang Ying ◽

Zhang Yunhe ◽

Niu Yaming ◽

Na Ying ◽

Jiang Zhenhua

Keyword(s):

Thermal Stability ◽

Weight Loss ◽

Glass Transition ◽

Free Radicals ◽

Crosslinking Reaction ◽

Transition Temperatures ◽

Aryl Ether ◽

Glass Transition Temperatures ◽

Good Thermal Stability ◽

Thermal Crosslinking

AbstractFour new poly(aryl ether sulfone)s containing naphthalene rings were synthesized from 1,5- and 2,7-bis-(4-fluorosulfonyl)naphthalene isomers with different diphenols. These polymers exhibited high glass transition temperatures and good thermal stability. The glass transition temperatures ranged from 220 to 236°C and the 5% weight-loss temperatures were above 423°C. As the four polymers were treated at 300°C, the glass transition temperatures of polymer series a obviously increased and the polymers became insoluble in common organic solvents including NMP, DMAc, and chloroform, etc., but the series b did not, which indicate that a thermal crosslinking reaction via free radicals happened leading to crosslinked polymers

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Naphthalene-based poly(aryl ether)s. II. Synthesis and characterization of poly(ether ketone)s containing two 1,4-naphthylene moieties in the repeat unit

Canadian Journal of Chemistry ◽

10.1139/v97-162 ◽

1997 ◽

Vol 75 (10) ◽

pp. 1346-1353 ◽

Cited By ~ 1

Author(s):

Zhi Yuan Wang ◽

Peter W. Broughton

Keyword(s):

Glass Transition ◽

Transition Temperature ◽

Repeat Unit ◽

Synthesis And Characterization ◽

Transition Temperatures ◽

Aryl Ether ◽

Glass Transition Temperatures ◽

Phenyl Sulfone ◽

Ether Ketone

Two new monomers, 4-chloro-1-(4′-fluoro-1-naphthoyl)naphthalene and 1,4-bis(4′-fluoro-1′-naphthoyl)benzene, have been synthesized and polymerized with four different bisphenols to give two series of the naphthalene-based poly(ether ketone)s that are analogous to commercial PEEK and PEEKK. The effect of the introduction of one or two 1,4-naphthylene moieties, in the backbone of the repeat unit, on the glass transition temperatures has been studied. The glass transition temperatures usually increased by 20–45 °C upon replacing one 1,4-phenylene with one 1,4-naphthylene moiety. All new poly (ether ketone)s prepared in tetramethylene sulfone were amorphous, with the glass transition temperatures in a range of 212–273 °C. The polymer produced from 1,4-bis(4′-fluoro-1′-naphthoyl)benzene and 1,4-hydroquinone in phenyl sulfone as a solvent at 300 °C showed semicrystalline properties with a melting temperature of 310 °C. Keywords: naphthalene, poly(ether ketone)s, synthesis, characterization, glass transition temperature.

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Synthesis and characterization of novel cyanofunctionalized poly(aryl ether ketone)s

e-Polymers ◽

10.1515/epoly.2009.9.1.997 ◽

2009 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

Yunhe Zhang ◽

Dianfu Ren ◽

Shaowei Guan ◽

Ying Na ◽

Guibin Wang ◽

...

Keyword(s):

Glass Transition ◽

Transition Temperatures ◽

Aryl Ether ◽

Excellent Thermal Stability ◽

Glass Transition Temperatures ◽

Young’S Moduli ◽

Flexible Films ◽

Aryl Ether Ketone ◽

Ether Ketone

AbstractA series of cyanophenyl-substituted poly(aryl ether ketone)s (PAEKs) have been successfully synthesized from two new bisphenol monomers, (3,4- dicyano) phenylhydroquinone and (4-cyano) phenylhydroquinone respectively, and the thermal behaviour and the solubility have been characterized. These polymers exhibited high glass transition temperatures and excellent thermal stability. The glass transition temperatures ranged from 173 to 217 oC, and 5% weight-loss temperatures were above 470 oC. The solubilities of these polymers have been remarkably improved in common organic solvents over PEEK and PEN. Some polymers formed transparent, strong, and flexible films, with tensile strength of 106.5-125.2 MPa, Young’s moduli of 2.68-3.20 GPa, and elongations at break of 9- 16 %.

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