Novel Combination of Vinyl Benzoxazine and Its Copolymerizable Diluent with Outstanding Processability for Preparing a Bio-Based Thermoset

Abstract

The application of polybenzoxazine resin still remains a puzzling problem in processability due to the high melting temperature of benzoxazine. Here, a bio-based reactive diluent, 4-vinyl guaiacol acetate (AC4VG), and a bio-based benzoxazine monomer, 4VG-fu, were synthesized using the diluent-based strategy for improving the poor processability of benzoxazine. 4VG-fu and AC4VG show good miscibility, and their mixture solutions exhibit a very low viscosity. When the mixtures are heated, free radical copolymerization of 4VG-fu and AC4VG takes place at a low temperature range (120−140 °C), and ringopening polymerization of the benzoxazine groups pendant to the copolymer chains occurs at a higher temperature range (140−220 °C). The last polymerization induces microphase separation in the cured resin, and the AC4VG/4VG-fu molar ratio exerts an important effect on the degree. The AC4VG/4VG-fu solutions also show good suitability with cotton fabrics for preparing composite materials, resulting in satisfactorily thermal and dynamic mechanical properties. These results suggest an effective strategy for improving the processability of benzoxazines, opening a way to develop fully bio-based polybenzoxazine resins with high performance.

Design of a green chemoenzymatic cascade for scalable synthesis of bio-based styrene alternatives

“…Among these new strategies many build on the use of hydroxystyrene monomers. [2][3][4][5][6][7][8][9][10][11][12][13] Their great appeal resides in their aromatic hydroxy groups, as they offer scope for modifications to tune mechanical properties and to design self-healing materials. 3,4 In addition, hydroxystyrenes are common building blocks in lignocellulosic biomass, meaning that they can be derived from the most abundant renewable feedstock there is.…”

“…These, however, are reactive and are thought to undergo uncontrolled oligomerization complicating their isolation, storage and polymerization. [8][9][10] Although controlled polymerization of unprotected hydroxystyrenes has been demonstrated, it requires demanding conditions (−40 °C, N 2 atmosphere) 6 or yields drastically lower conversion than styrene. 2 This is due to their protic phenol groups, which are detrimental to many conventional polymerization techniques.…”

“…8 Both acetylation and silylation have been found to produce monomers that enable efficient polymerization and result in well controlled molecular weight distributions and material properties. [8][9][10][11][12][13] For cases in which these protection groups are of transient utility, selective deprotection protocols have been established. 7,8,[10][11][12][13] Analogous to the well-known duo of polyvinyl alcohol and polyvinyl acetate, both protected and deprotected polyhydroxystyrenes are of interest.…”

Highly Bio‐Based Unsaturated Polyester Resins with Improved Performance by Incorporating Isosorbide into the Polyester Prepolymer

“…With increasing environmental concerns on both the depletion of petroleum source and the burdensome waste treatment, design, and synthesize of renewable polymers have been presented as a new development direction of polymer chemistry. [1][2][3][4][5] After successful commercialization of several bio-based thermoplastics such as polylactic acid (PLA), [6,7] polyhydroxyalkanoates DOI: 10.1002/mame.202200203 (PHA), [8,9] and polybutylene succinate (PBS), [10] polymerization of bio-based thermosetting resins like epoxy resins, [11,12] furan resins, [13,14] benzoxazine resins, [15][16][17][18][19][20][21] urea-formaldehyde resins, [22,23] and unsaturated polyester resins (UPRs) [24,25] have been reported extensively.…”

A novel benzoxazine derived from diphenol amide for toughing commercial benzoxazine via copolymerization

“…[1][2][3] Among the merits such as near-zero chemical releasing, 4 volumetric shrinkage upon curing, 5 good thermal stability, 7,8 excellent mechanical performance, 4 high glass transition temperature, 4,6 lowdielectric constant, 9 low-surface energy, 10 low-water absorption, 6 and high flame retardancy, [11][12][13][14] the molecular design flexibility of benzoxazine is most attractive because it can regulate performance of the thermosetting resin. [15][16][17][18][19][20][21][22] However, several intrinsic disadvantages of polybenzoxazines limited the range of their applications. For example, most benzoxazine monomers have to be cured at a high temperature, and almost all polybenzoxazines are of brittle feature.…”