Functional 1,3‐benzoxazine bearing 4‐pyridyl group: Synthesis and thermally induced polymerization behavior

Abstract

1,3‐benzoxazine 1, bearing 4‐pyridyl moiety on the nitrogen atom, was synthesized from p‐cresol, 4‐aminopyridine, and paraformaldehyde. The efficient synthesis was achieved by adding acetic acid to suppress the strong basicity caused by the presence of 4‐aminopyridine derivatives. Upon heating 1 at 180 °C, it underwent the thermally induced ring‐opening polymerization. The resulting polymer was composed of two types of repeating unit, i.e., (1) Mannich‐type one (‐phenol‐CH2‐NR‐CH2‐) that can be expected from the general ring‐opening polymerization of conventional benzoxazines and (2) a typical phenolic resin‐type one (‐phenol‐CH2‐phenol‐) induced by release of 4‐aminopyridine and paraformaldehyde (unit B). Another structural feature of the polymer was that it possessed a benzoxazine moiety at the chain end. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 410–416

Azopyridine-functionalized benzoxazine with Zn(ClO4)2form high-performance polybenzoxazine stabilized through metal–ligand coordination

“…The introduction of the 4-aminopyridyl moiety resulted in a polymer exhibiting high affinity toward metal ions [e.g., copper(II), cobalt(II)], leading to the production of polymer-metal complexes in the form of insoluble colored precipitates. 41,51 Furthermore, among known photoresponsive molecules, azobenzene derivatives are the most popular for photo switching applications 52,53 because they can photoisomerize reversibly between their planar trans form and nonplanar cis form upon irradiation with light. Azobenzene derivatives have two major advantages over other molecules when used as photoswitches: their chemical synthesis is relatively simple (indeed, some are commercially available) and they exhibit chemical stability, allowing repeated trans-to-cis photoisomerizations without decomposition-even under aqueous conditions.…”

Synthesis of novel furan-containing tetrafunctional fluorene-based benzoxazine monomer and its high performance thermoset

“…Studies have reported that the strong basicity of the amine could lower the stability of the oxazine ring in alkaline environment. 25,26 Thus, the basic furfurylamine leads to the ring-opening of oxazine ring in the presence of these basic deprotecting agents.…”

Low-Dissipation Thermosets Derived from Oligo(2,6-Dimethyl Phenylene Oxide)-Containing Benzoxazines

“…Polybenzoxazines feature for special characteristics such as a moderate-to-high thermal property [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ], moderate electrical property [ 19 ], low water absorption [ 20 ], and low surface energy [ 21 ]. Low-dielectric benzoxazines have been reported (1) by Chang et al through Mannich condensation of bisphenol F/4-(trifluoromethyl)aniline/formaldehyde [ 22 ]; (2) by Liu et al through incorporation of methyl methacrylate-POSS (MMA-POSS) into the network of bis(3-furfuryl-3,4-dihydro-2 H -1,3-benzoxazinyl)isopropane (BPA-FBz), which has furfuryl moiety that can react with methyl methacrylate through the Diels-Alder reaction [ 23 ]; (3) by Liu et al through the incorporation of a benzobisoxazole structure [ 24 , 25 ]; (4) by Alagar et al through the incorporation of silica (SBA-15) [ 26 ]; (5) by Ishida et al from a highly fluorinated diamine and bisphenol F [ 27 ]; and (6) by Lin et al from fluorinated aromatic diamine [ 28 ].…”