Synthesis and crosslinking reaction of a novel polymer containing benzoxazine and phenyleneethynylene moieties in the main chain

Abstract

A novel polymer, poly(1) containing benzoxazine and phenyleneethynylene moieties in the main chain with number‐average molecular weights ranging from 1400 to 9800 was obtained quantitatively by the Sonogashira–Hagihara coupling polymerization of the corresponding iodophenyl‐ and ethynylphenyl‐substituted monomer 1. Poly(1) was heated at 200 °C under N2 for 2 h to obtain the cured polymer, poly(1)′ via the ring‐opening polymerization of the benzoxazine moieties. The structures of the polymer before and after curing were confirmed by 1H‐NMR, IR, and UV–vis absorption and reflectance spectroscopies. Poly(1)′ was thermally more stable than monomer 1 and poly(1). A specimen was prepared from a mixture of poly(1) and phenol‐diaminodiphenylmethane type benzoxazine 2 by heating at 200 °C for 2 h under N2. The poly(1)/2 resin was thermally stable than bisphenol‐A type benzoxazine resin 3. Poly(1) exhibited XRD peaks corresponding to the d‐spacings of 1.26–0.98 and 0.40 nm, assignable to the repeating monomer unit and alignment of polymer molecules, respectively. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2581–2589

Ethynylene-linked multifunctional benzoxazines: the effect of the ethynylene group and packing on thermal behavior

“…We have reported the synthesis and curing behavior of various ethynylene-linked benzoxazines, including anthracenylethynylene 23 and phenyleneethynylene, 24 and also polyacetylenes bearing benzoxazine moieties. 25 We have determined that incorporation of ethynylene and π-conjugated moieties can enhance the thermal stability of benzoxazines by formation of network structures during the ring-opening polymerization of benzoxazine moieties or by incorporation of ethynylene moieties.…”

“…For ESI and crystallographic data in CIF or other electronic format see DOI: https://doi.org/10.1039/d2py00840h a Department of Chemistry and Materials Engineering, Faculty of Chemistry, Materials and Bioengineering, Kansai University, 3-3-35 Yamate-cho, Suita, Osaka 564-8680, Japan. E-mail: sanda@kansai-u.ac.jp lethynylene 23 and phenyleneethynylene, 24 and also polyacetylenes bearing benzoxazine moieties. 25 We have determined that incorporation of ethynylene and π-conjugated moieties can enhance the thermal stability of benzoxazines by formation of network structures during the ring-opening polymerization of benzoxazine moieties or by incorporation of ethynylene moieties.…”

Synthesis and Cross-Linking of a Benzoxazine-Containing Anthracene Moiety: Thermally Stable Photoluminescent Benzoxazine Resin

“…We consider that the rigid polyacetylene backbone disturbs the molecular motion of the ring-opened benzoxazine moieties, leading to the suppression of hydrogen bonding between the amino and hydroxy groups formed by the ring-opening of the benzoxazine moieties. We have also synthesized a poly­(phenylene–ethynylene)-based benzoxazine resin that exhibits a high thermal diffusivity originating from the rigid phenylene–ethynylene backbone …”

“…We have also synthesized a poly(phenylene−ethynylene)-based benzoxazine resin that exhibits a high thermal diffusivity originating from the rigid phenylene−ethynylene backbone. 34 In this paper, we report a novel benzoxazine tethered to anthracene through ethynylene groups to develop thermally stable benzoxazine resins exhibiting the synergistic effect of the rigid anthracene backbone and benzoxazine moieties. The anthracene-tethered benzoxazines are also expected to show variable photoluminescence according to the conversion of ring-opening polymerization of the benzoxazine moieties.…”