Photo-induced reversibility as a tool for self-healing: a reversible photo-induced dendritic macromonomer was synthesized and proven to form networks with different features depending on the crosslinking conditions. While networks formed from aqueous systems exhibited a reversible change in their crosslinking degree, networks generated in bulk underwent fully reversibility. The latter was then exploited for generating self-healing materials by means of a photo-induced treatment.

A novel difunctional benzoxazine with o-trifluoroacetamide functionality has been synthesized via Mannich condensation. The chemical structure of synthesized monomer has also been confirmed by 1H, 13C, and 19F nuclear magnetic resonance (NMR) spectroscopy and Fourier transform infrared (FT-IR) spectroscopy. The ring-opening polymerization of the resin and the subsequent conversion of the freshly generated polybenzoxazine into polybenzoxazole are studied by FT-IR and differential scanning calorimetry (DSC). In addition to the advantage of low polymerization temperature as other reported o-amide benzoxazines, the o-trifluoroacetamide benzoxazine also exhibits an unexpected lower benzoxazole formation temperature. Furthermore, the resulting fluorinated polybenzoxazole derived from the benzoxazine monomer possesses the combined excellent properties of facile synthesis, easy processability, low dielectric constant, high thermal stability, and long shelf life, evidencing its potential applications in microelectronic industries, aerospace, and other high-performance areas.

What inspired you for the cover image? Perhapst he analogy with as pace travel across the universe where no matter the direction there are always new amazing 'things' to be discovered, letting us know and appreciate deeper what we have in hand. Af ew years ago, only very few examples of naturally based benzoxazines were known.T hat was the early stages of aj our-ney that today may be seen as the development of an ovel full topic, biomass-based benzoxazinesa nd polybenzoxazines. Nowadays, new materials based on natural renewable raw materials are investigated, studied, formulated, and applied. Those early 'launches' helpedt o'launch' this novel yet established field within the benzoxazines'a rena, represented in the cover as the 'Green Galaxyo fBenzoxazines'. What is in your opinion an upcoming research theme likely to becomeo ne of the 'hot topics' in the near future? It is hard to make futurology in this sense because there are so many different and equally relevant fields, each of them with their respective subdisciplines. Nevertheless, what we can envisage is that regardless what the upcomingh ot topic or topics might be, they will certainly have to involve the right tools to efficientlyd esign and develop novel materials exploiting good chemistry based on renewable natural resources and sustainability.T his last concept applies not only to the materials themselves but also to their raw materials and methodolo-gies used. Invited for this month'sc over are the groups at the

The future evolution of benzoxazines and polybenzoxazines as advanced molecular, structural, functional, engineering, and newly commercial materials depends to a great extent on a deeper and more fundamental understanding at the molecular level. In this contribution, the field of benzoxazines is briefly introduced along with a more detailed review of ortho-amide-functional benzoxazines, which are the main subjects of this article. Provided in this article are the detailed and solid scientific evidences of intramolecular five-membered-ring hydrogen bonding, which is supposed to be responsible for the unique and characteristic features exhibited by this ever-growing family of ortho-functionalized benzoxazines. One-dimensional (1D) (1)H NMR spectroscopy was used to study various concentrations of benzoxazines in various solvents with different hydrogen-bonding capability and at various temperatures to investigate in detail the nature of hydrogen bonding in both ortho-amide-functionalized benzoxazine and its para counterpart. These materials were further investigated by two-dimensional (2D) (1)H-(1)H nuclear Overhauser effect spectroscopy (NOESY) to verify and support the conclusions derived during the 1D (1)H NMR experiments. Only highly purified single-crystal benzoxazine samples have been used for this study to avoid additional interactions caused by any impurities.

Sesamol and furfurylamine are used to synthesize a novel benzoxazine monomer as part of the quest to develop greener benzoxazine monomers simultaneously fulfilling two Principles of Green Chemistry, the use of renewable feedstocks and safer solvents and auxiliaries. Respecting principle 5, the so-called preferred solvents (ethanol and ethyl acetate) are used in both the syntheses and purification processes. The chemical structure of the synthesized monomer is verified by proton and carbon nuclear magnetic resonance spectroscopy (1H and 13C NMR), 2D 1H–13C heteronuclear single quantum correlation (HSQC) spectroscopy, and Fourier transform infrared spectroscopy (FT-IR). The polymerization behavior of the monomer and the thermal stability of fully polymerized polybenzoxazine are studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). A thermally stable polymer has been obtained as shown by the 5% and 10% weight reduction temperature (T d5 and T d10) values of 374 and 419 °C, respectively, and a char yield of 64%, making this thermoset a promising candidate for fire-resistant applications.

A fully bio-based benzoxazine containing latent catalytic system is designed and successfully synthesized and it can be used as both an initiator and a beneficial property modifier of other thermosetting systems, especially for fire related properties.

A new fully biobased trioxazine benzoxazine is synthesized by reacting resveratrol, furfurylamine, and paraformaldehyde via the Mannich condensation reaction. The chemical structure of this biobenzoxazine is characterized by 1 H and 13 C nuclear magnetic resonance and Fourier transform infrared (FT-IR) spectroscopies. 1 H− 1 H nuclear Overhauser effect spectroscopy is utilized to unambiguously identify the isomer obtained. Monomer polymerization is investigated by differential scanning calorimetry and in situ FT-IR. Thermal stability of the fully polymerized polybenzoxazine is evaluated by thermogravimetric analysis, and flammability is assessed by microscale combustion calorimetry. The biothermoset obtained shows high thermal stability and low flammability, T d10 of 403°C and char yield of 64%, respectively, low heat release capacity (54 J/gK), and low total heat release (9.3 KJ/g), thus exhibiting self-extinguishing and nonignitable properties. Consequently, this new fully biobased trioxazine benzoxazine and its corresponding polybenzoxazine possess excellent processability and thermal properties, suggesting great potential toward high-performance and fire-resistant materials.

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