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

e-Polymers ◽  
2008 ◽  
Vol 8 (1) ◽  
Author(s):  
Zhang Ying ◽  
Zhang Yunhe ◽  
Niu Yaming ◽  
Na Ying ◽  
Jiang Zhenhua

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

2018 ◽  
Vol 31 (8) ◽  
pp. 909-918 ◽  
Author(s):  
Xiao-Lan Zhang ◽  
Cheng Song ◽  
Mei-Hong Wei ◽  
Zhen-Zhong Huang ◽  
Shou-Ri Sheng

9,9-Bis(4-aminophenyl)xanthene (BAPX) was prepared simply and effectively via one-pot, two-step procedure using xanthenone and aniline as main substrates. The monomer BAPX was reacted with six aromatic dianhydrides in N, N-dimethylacetamide (DMAc) to yield the corresponding polyimides (PIs) via the poly(amic acid) precursors and subsequent thermal or chemical imidization. The resulting PIs exhibited good thermal stability with glass transition temperatures of 308–348°C, initial decomposition temperatures of 470–510°C, 10% weight loss temperatures of 540–565°C, and char yields of 55–59% at 800°C in nitrogen, respectively. All polymers were amorphous and readily soluble in organic solvents such as N-methyl-2-pyrrolidone and DMAc. The PI films had tensile strengths of 71–92 MPa, tensile moduli of 1.91–2.35 GPa, and elongations at break of 5–13%. Meanwhile, these polymer films also had high optical transparency with a cutoff wavelength in the range of 367–415 nm, lower dielectric constants (3.02–3.34 at 10 MHz), and low water uptake of 0.30–0.52%.


2011 ◽  
Vol 217-218 ◽  
pp. 1606-1610
Author(s):  
Dong Jiang ◽  
Xiao Ran Zhang ◽  
Yan Mei Ma ◽  
Cheng You Ma

A series of random polysulfone/polyethersulfone (PSF/PES) copolymers were synthesized by the polycondensation of 4, 4'-isopropylidendiphenol, 4, 4΄-dihyolroxy diphenyl sulfone and 4, 4'-dichlorodiphenyl sulfone in the presence of K2CO3. We obtained a series of copolymers by changing the molar ratio of 4, 4΄-dihyolroxy diphenyl sulfone and 4, 4'-isopropylidendiphenol (it was marked as the ratio of S:A). The copolymers have the similar solubility with polyethersulfone. They also have high glass transition temperatures (Tg: 199°C~229°C) and 5% weight loss temperatures (4, 4'-isopropylidendiphenol: 4, 4΄-dihyolroxy diphenyl sulfone=1:1, Td5=497°C). At the same time the elongation at break is much higher than that of PES, while the tensile strength is a little lower than that of PES.


1995 ◽  
Vol 7 (4) ◽  
pp. 481-492 ◽  
Author(s):  
Rajendra K Singh ◽  
Rooma Mago Mehta ◽  
R G Bass

A series of eight novel extended poly(phenylquinoxalines) (PPQs) containing carbonyl, ether and sulphide linking groups were prepared by polycondensation of 4,4'-bis(phenylglyoxalyl-4-phenoxy-4'-benzoyl)diphenyl sulphide, I-D, and 4,4'-bis(phenyl glyoxalyl-4-phenylthio-4'-benzoyl)diphenyl sulphide, 2-D, with four aromatic bis(o-diamines) in m-cresol. The primary objective of this study was to correlate the effect of these linkages on the various properties such as solubility, thermal stability and glass transition temperature of the PPQs. Polymerization of 1-D was carried out in an oil bath maintained at 195-200C whereas polymerization of 2-D was performed at ambient temperature. The polymers prepared were soluble in m-cresol. dimethylsulphoxide, N,N-dimethylacetamide, I-methyl-2-pyrrolidinone and chlorinated hydrocarbon solvents, and formed tough transparent, yellow fingernail-creasable films from chloroform solutions. The inherent viscosities ranged between 0.44 and 0.96 dl g' '. The glass transition temperatures were nearly identical for both systems and ranged from 217-231 'C for polymers prepared from l-D and from 215-233"C for polymers prepared from 2-D. The PPQs having carbonyl and stJlphide linking groups had higher thermal stability in comparison to PPQs having carbonyl, ether and sulphide linkages. The temperature of 10% weight loss for I-D ranged from 484-496 'C in air and 485-516"C in helium whereas those for 2-D ranged from 538-579 XC in air and 522-549 in helium.


2003 ◽  
Vol 15 (3) ◽  
pp. 281-290 ◽  
Author(s):  
Yoshio Imai ◽  
Mina Ishida ◽  
Masa-Aki Kakimoto

A new aromatic diamine monomer, N,N′-bis(4-aminophenyl)-N,N′-diphenyl-4,4′-biphenyldiamine, was first synthesized in two steps by the condensation of N,N′-diphenyl-4,4′-biphenyldiamine with 4-fluoronitrobenzene, followed by reduction. New triphenylamine-containing aromatic polyimides having inherent viscosities of 0.67-0.91 dl g−1 were synthesized from the aromatic diamine and various aromatic tetracarboxylic dianhydrides by the conventional two-step procedure that included ring-opening polyaddition giving precursor polyamic acids and subsequent thermal cyclodehydration. Most of the aromatic polyimides were soluble on heating in organic solvents such as dimethylacetamide, m-cresol, pyridine, and chloroform, and gave flexible and tough films with good tensile properties. The glass transition temperatures and 10% weight loss temperatures of the polyimides were in the range of 293-361 and 565-595 °C, respectively, in nitrogen.


1997 ◽  
Vol 75 (10) ◽  
pp. 1346-1353 ◽  
Author(s):  
Zhi Yuan Wang ◽  
Peter W. Broughton

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.


1992 ◽  
Vol 4 (2) ◽  
pp. 73-80 ◽  
Author(s):  
F. W. Mercer

Two oxadiazole containing aromatic diamines were synthesized. The diamines were prepared by reaction of aminophenols with 2,5-bis(4-fluorophenyl)-4l3,4-oxadiazole in a polar aprotic solvent in the presence of potassium carbonate. Reaction of the resulting 2,5-bis(4-(aminophenoxy)phenyl)-1,3,4-oxadiazoles with dianhydrides gave a series of polymeric amic acids. Thermal treatment yielded poly(imide ether oxadazole) films which displayed good thermal stability, flexibility, and glass transition temperatures ranging from 241 to 344C. The dielectric constants of the films were characterized as a function of relative humidity.


e-Polymers ◽  
2009 ◽  
Vol 9 (1) ◽  
Author(s):  
Yunhe Zhang ◽  
Dianfu Ren ◽  
Shaowei Guan ◽  
Ying Na ◽  
Guibin Wang ◽  
...  

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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