Synthesis and properties of phenylethynyl-terminated, star-branched, phenylquinoxaline oligomers

Ooi, Ing Hong; Hergenrother, P. M.; Harris, Frank W.

doi:10.1016/s0032-3861(99)00572-8

Cited by 16 publications

(13 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1). 11, 12, 14, 16–20 1 readily undergoes polycondensation into a high‐molecular‐weight polymer only when the reaction conditions are very carefully controlled. To continue our research, for the first design of a new monomer mixture, 3‐(4‐fluorophenyl)‐2‐phenyl‐6‐hydroxyquinoxaline and 2‐ (4‐fluorophenyl)‐3‐phenyl‐6‐hydroxyquinoxaline ( 2 ), we switched the positions of the functional groups, that is, the hydroxyl group and the fluorine atom (Fig.…”

Section: Resultsmentioning

confidence: 99%

“…A recent, less expensive approach to PPQs involves nucleophilic substitution reactions of bisphenoxide salts with activated aromatic dihalides4–10 in polar aprotic solvents. A self‐polymerizable PPQ monomer that contains both a phenate nucleophile and a fluorine atom activated by a pyrazine ring for nucleophilic substitution has been prepared in this laboratory 11–20. AB monomer 1 , which exists as two isomers, 3‐(4‐hydroxyphenyl)‐2‐phenyl‐6‐fluoroquinoxaline and 2‐(4‐hydroxyphenyl)‐3‐phenyl‐6‐fluoroquinoxaline (Fig.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Synthesis and polymerization of new self‐polymerizable quinoxaline monomers

Baek

Harris

2004

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

Extended self‐polymerizable poly(phenylquinoxaline) monomer mixtures {i.e.,2‐[4‐(4‐hydroxyphenoxy)phenyl]‐3‐phenyl‐6‐chloroquinoxaline and 3‐[4‐(4‐hydroxy phenoxy)phenyl]‐2‐phenyl‐6‐chloroquinoxaline, 2‐[4‐(4‐hydroxyphenoxy)phenyl]‐3‐phenyl‐6‐fluoroquinoxaline and 3‐[4‐(4‐hydroxyphenoxy)phenyl]‐2‐phenyl‐6‐fluoroquinoxaline, and 2‐(4‐fluorophenyl)‐3‐phenyl‐6‐(4‐hydroxyphenoxy)quinoxaline and 3‐(4‐fluorophenyl)‐2‐phenyl‐6‐(4‐hydroxyphenoxy)quinoxaline} more flexible and nucleophilic than a previously reported monomer mixture [i.e., 3‐(4‐hydroxyphenyl)‐2‐phenyl‐6‐fluoroquinoxaline and 2‐(4‐hydroxyphenyl)‐3‐phenyl‐6‐fluoroquinoxaline] were synthesized. The monomer mixtures were then polymerized into high‐molecular‐weight polymers. A sample was obtained, through a chlorine displacement reaction, that was a semicrystalline polymer with an intrinsic viscosity of 1.11 dL/g in m‐cresol at 30 ± 0.1 °C and two melting temperatures at 339 and 377 °C in the first differential scanning calorimetry scan. There was a melting temperature at 328 °C without a detectable glass‐transition temperature (Tg) when the sample was subjected to a second differential scanning calorimetry scan. The samples from fluorine displacement reactions were completely amorphous polymers. They had intrinsic viscosities of 0.53–0.90 dL/g in m‐cresol at 30 ± 0.1 °C and Tg's of 220–224 °C. The polymer samples from fluorine displacement reactions were evaluated with gel permeation chromatography and matrix‐assisted laser desorption/ionization time‐of‐flight analyses, which monitored the existence of certain amounts of cyclic oligomers. The thin films of the polymers had room‐temperature tensile strengths of 97–113 MPa, room‐temperature Young's moduli of 2.30–2.35 GPa, and room‐temperature elongations at break of 40–150%. The melt viscosity decreased from 107 to less than 104 Pa s at 310 °C as the frequency was increased from 10−2 to 102 rad/s. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 78–91, 2005

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Synthesis and polymerization of new self‐polymerizable quinoxaline monomers

Baek

Harris

2004

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

show abstract

“…This reached a maximum when BPP was cured at 400 °C in nitrogen for 16 h, where the T g was found to be close to 450 °C (Fig. 2), considerably higher than the T g values exhibited by phenylethynyl terminated imide (PETI) systems 19, 20…”

Section: Resultsmentioning

confidence: 89%

N‐(2‐biphenylenyl)‐4‐[2′‐phenylethynyl] phthalimide: 2. Detailed study of the monomer cure and properties of the resulting polymer

Georgiades

Hamerton

Hay

et al. 2004

Polymer International

View full text Add to dashboard Cite

A detailed study is presented of the high‐temperature cure of the difunctional monomer N‐(2‐biphenylenyl)‐4‐[2′‐phenylethynyl]phthalimide (BPP) and the thermal properties of the resulting homopolymer. Although the phenylethynyl groups are consumed within 1 h at 370 °C, other reactions continue well after this, leading to a cured polymer whose glass transition temperature (Tg) is highly dependent on cure time and temperature. A Tg of 450 °C is achieved after a 16 h cure at 400 °C. Use of chemometrics to analyse the infrared spectra of curing BPP provides evidence for changes in the aromatic moieties during cure, perhaps indicative of co‐reaction between the biphenylene and phenylethynyl groups; however, other processes also contribute to the overall complex cure mechanism. Despite the high Tg values, BPP homopolymer exhibits unacceptably poor thermo‐oxidative stability at 370 °C, showing a weight loss of about 50 % after 100 h ageing. This is perhaps a result of formation of degradatively unstable crosslink structures during elevated‐temperature cure. Copyright © 2004 Society of Chemical Industry

show abstract

“…[1][2][3] Strategies to prepare processable examples have focused on incorporation of flexible groups to prepare either soluble precursors, [1][2][3]8,14] or branched, hyperbranched, and dendritic polymers. [19][20][21][22][23] Branching of a growing polymer while maintaining controlled functional group conversion and subsequent reactivity prior to vitrification is effective yet often limited because of arduous synthetic requirements. We have previously reported the synthesis and preliminary polymerization studies of easily prepared tetraynes, or bis-ortho-diynylarene (BODA) monomers, as a route to high performance aromatic polymers via readily processable intermediates.…”

Section: Introductionmentioning

confidence: 99%

Polyarylene Networks via Bergman Cyclopolymerization of Bis‐ortho‐diynyl Arenes

Smith¹,

Shah²,

Perera³

et al. 2007

Adv Funct Materials

View full text Add to dashboard Cite

Bis‐ortho‐diynylarene (BODA) monomers, prepared from common bisphenols in three high yielding steps, undergo free‐radical‐mediated thermal polymerization via an initial Bergman cyclo‐rearrangement. Polymerization is carried out at 210 °C in solution or neat with large pre‐vitrification melt windows (4–5 h) to form branched oligomers containing reactive pendant and terminal aryldiynes. Melt‐ and solution‐processable oligomers with weight‐average molecular weight Mw = 3000–24 000 g mol–1 can be coated as a thin film or molded using soft lithography techniques. Subsequent curing to 450 °C affords network polymers with no detectable glass transition temperatures below 400 °C and thermal stability ranging from 0.5–1.5 % h–1 isothermal weight loss measured at 450 °C under nitrogen. Heating to 900–1000 °C gives semiconductive glassy carbon in high yield. BODA monomer synthesis, network characterization and kinetics, processability, thin‐film photoluminescence, and thermal properties are described.

show abstract

Synthesis and properties of phenylethynyl-terminated, star-branched, phenylquinoxaline oligomers

Cited by 16 publications

References 13 publications

Synthesis and polymerization of new self‐polymerizable quinoxaline monomers

Synthesis and polymerization of new self‐polymerizable quinoxaline monomers

N‐(2‐biphenylenyl)‐4‐[2′‐phenylethynyl] phthalimide: 2. Detailed study of the monomer cure and properties of the resulting polymer

Polyarylene Networks via Bergman Cyclopolymerization of Bis‐ortho‐diynyl Arenes

Contact Info

Product

Resources

About