Synthesis and thermal behaviour of thiophene-based oxazine-ring substituted benzoxazine monomers & polymers

Abstract

The latest fourth-generation oxazine-ring substituted thiophene-based benzoxazine monomers and polymers with variation in the degree of phenyl substitution (with and without) in oxazine-ring were synthesized and characterized. Thiophene-based di-substituted benzoxazine...

Thiophene-Rich Benzoxazines with an Amide Moiety: Integration of Structural and Hydrogen Bonding Influence on the Polymerization Mechanism by Experimental and Computational Studies

“…25,27 Additionally, the existence of the flexible methylene group between the nitrogen of the oxazine ring and the thiophene ring in monomers can increase the conformational freedom to enhance the participation of thiophene in electrophilic aromatic crosslinking reactions. 30 The polymerization mechanisms of oTA-ta, pTA-ta, oTAc-ta, and pTAc-ta are proposed in Scheme 2.…”

“…3-(Thiophen-2-ylmethyl)-3,4-dihydro-2H-benzo[e] [1,3]oxazine (PH-ta) was prepared according to a reported method. 30 Characterization. FT-IR spectra of newly synthesized phenolic compounds, benzoxazine monomers, and polybenzoxazine samples were recorded on a Nicolet MX-1E FT-IR spectrometer, and the scanning range of each spectrum was 400−4000 cm −1 .…”

Preparation, polymerization and properties of an adamantyl‐based benzoxazine

“…Benzoxazines, a novel class of phenolic resin, are synthesized from primary amine compounds, phenolic compounds and formaldehyde through Mannich condensation [1][2][3][4][5] and can undergo thermal ring-opening polymerization to form polybenzoxazine without the addition of catalysts. 1,[6][7][8] Polybenzoxazines not only possess the advantages of traditional phenolic resins, such as excellent thermal properties and flame retardance, but they also exhibit some unique features, such as near-zero volumetric expansion or shrinkage upon polymerization, non-generation of harmful byproducts during curing, low surface energy, low water absorption and high char yield. 3,6,[9][10][11][12][13] Nevertheless, several drawbacks have been identified when utilizing polybenzoxazine alone, namely fragility, decreased heat resistance and high dielectric constant, which to some extent restrict the application of the benzoxazine resins.…”

Formaldehyde-Free Synthesis of Fully Bio-Based Multifunctional Bisbenzoxazine Resins from Natural Renewable Starting Materials

“… − Holly and Cope prepared the first monofunctional BZ, 3,4-dihydro-2 H -1,3-benzoxazine, through Mannich condensation . Although the chemical structures of PBZs are similar to those of traditional phenolic resins, PBZs are generally prepared by using simple and self-catalyzed polymerization processes and display good heat resistance, high degradation and glass transition ( T g ) temperatures, near-zero volumetric shrinkage during polymerization, excellent flame retardancy, good mechanical properties, low dielectric constants, water absorption properties, and variable surface free energies. ,− In addition, high flexibility in the molecular design of BZ resins allows a variety of physical and mechanical properties to be introduced into the resulting PBZ materials. − Moreover, the properties of PBZs lead to many potential applications in, for example, adsorbents, metal capture, energy storage, gas uptake, shape-memory and self-healing polymers, anticorrosion coatings, adhesives, and electronic materials. − The syntheses and characteristics of mono-, bi-, tri-, and tetrafunctional BZs have been investigated in detail by many research groups. ,,,,,,, In general, monofunctionalized BZs tend to form linear polymers of relatively lower molecular weight, while bifunctional BZs form cross-linked macromolecules featuring more stable networks …”