Novel heterocyclic poly(arylene ether ketone)s: Synthesis and polymerization of 4‐(4′‐hydroxyaryl)(2H)phthalazin‐1‐ones with methyl groups

Abstract

Based on green chemistry, a simple and efficient direct synthesis of 4‐(4′‐hydroxyaryl)(2H)phthalazin‐1‐ones (2a–2f) was developed in a two‐step reaction, in which the Friedel–Crafts acylation reaction of six phenols with phthalic anhydride was initially carried out and then followed by cyclization with hydrazine hydrate in good to excellent yields with high regioselectivity. A number of novel heterocyclic poly(arylene ether ketone)s were prepared conveniently from several unsymmetrical, twist, and noncoplanar phthalazinone‐containing monomers (2a–2f) and an activated difluoro monomer via a NC coupling reaction. It was very interesting that the obtained monomers and polymers exhibited diverse properties with the variation of the number and location of the substituted methyl groups. All these polymers had a high molecular weight with Mn and ηinh in the range of 44,960–169,000 Da and 0.38–0.79 dL/g, respectively. Actually, the obtained polymers displayed excellent thermal properties with Tg's ranging from 222 to 248 °C and 5% weight loss temperatures in nitrogen higher than 430 °C. Moreover, these polymers were readily soluble in common organic solvents, such as N‐methyl‐2‐pyrrolidone, chloroform, pyridine, and m‐cresol, and could be cast into flexible and colorless or nearly colorless films by spin‐coating or casting processes. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1525–1535, 2007

Poly(ether ether ketone)s and poly(ether ether ketone ketone)s containing cardo decahydronaphthalene groups: Synthesis and characterization

“…[5][6][7][8][9] In spite of their excellent performance, the processing and even the synthesis of PEEKs and PEEKKs has been limited because of their low solubility in common organic solvents resulting from their aromatic structure and semicrystallinity due to the high packing tendency of ketone and phenyl ether linkages in the main chain of PEEKs and PEEKKs. Many approaches have been tried toward the improvement of solubility and processability of PEEKs and PEEKKs which include the incorporation of noncoplanar structures, [10][11][12] pendent groups, and the alternation of the order and ratio of ether-ketone linkages 13,14 as well as meta and para-phenyl substitution. 15 The incorporation of cardo groups such as 9,9-diarylfluorene, 16 acenaphthenequinone, 17 spirodilactam, 18 phthalein, 19 and xanthene 19 into the backbone of poly(arylene ether ketone)s is an attractive approach toward enhanced solubility and glass transition temperature.…”

Comparative effect of phthalazinone units in sulfonated poly(arylene ether ether ketone ketone) copolymers as proton exchange membrane materials

“…Therefore, the phthalazinone monomer is used for preparing high-performance engineering plastics. [17][18][19] In the present work, a new series of poly(arylene ether ether ketone ketone) copolymers containing the phthalazinone unit (SPAEEKK-D) were prepared from commercially available monomers BFBB, DHNS, and DHPZ. Although there are a number of studies on PEM materials containing the phthalazinone unit, we are not aware of any that have attempted to compare its effect on polymer properties in comparison with other monomer units.…”

Synthesis and characterization of novel soluble poly(ether ketone sulfone)s with pendant polychloro groups

“…the FTIR spectroscopy ( Fig. 1), TCTPC showed strong characteristic carbonyl absorption at 1776 cm 21 . Figure 2 shows the 13 C NMR spectrum of TCTPC, in which all the carbons were assigned as expected.…”

“…The molecular weights of these polymers are sufficiently high to permit casting flexible and tough films. Figure 3 compares the FTIR spectra of all the resulting polymers, which exhibited the characteristic absorption bands around 1660 cm 21 corresponding to aryl carbonyl groups, around 1150 cm 21 corresponding to sulfone groups and around 1220 cm 21 due to aryl ether linkages. Additionally, FTIR spectra of polymers 3b, 3c, and 3d with a weak absorption bands around 2925 cm 21 , and a moderate strong absorptions around 1375 cm 21 are attributed to the stretching vibrations of the methyl groups.…”