Synthesis and Characterization of Partially Fluorinated Polybenzoxazine Resins Utilizing Octafluorocyclopentene as a Versatile Building Block

Abstract

Two new fluorinated diamine-based benzoxazines using octafluorocyclopentene (OFCP) as a building block have been developed. Monomers were synthesized via two distinct synthetic procedures utilizing the facile nucleophilic addition−elimination reaction of OFCP with phenols amenable to a multigram scale-up. The structure elucidation of both monomers was confirmed by 1 H, 19 F, and 13 C NMR, ATR-FTIR, and high-resolution mass spectrometry. Benzoxazine networks were prepared by a thermally mediated ring-opening polymerization. ATR-FTIR analysis was utilized to monitor the ring-opening reaction of the monomers. The resulting two cured resins exhibit the combined excellent properties of low dielectric constants (k = 3.2−2.6), excellent thermal stability, and high char yields which are suitable for many applications such as flame-resistant materials as well as aerospace and microelectronic industries.

Easily Processable Thermosets with Outstanding Performance via Smart Twisted Small‐Molecule Benzoxazines

“…The dielectric constant and dielectric loss (tan δ) of poly( o HPMI‐ac) were investigated at room temperature. As shown in Figure 4b, the dielectric constant decreased from 2.62 to 2.30 in the frequency range of 1 Hz to 10 MHz, which is comparable to other low‐ k polyimides and polybenzoxazoles 13,25. The dielectric loss of poly( o HPMI‐ac) varied from 0.004 to 0.015 in this frequency range.…”

Thermal Insulation Characteristics of Polybenzoxazine Aerogels

“…Ring‐opened polymerization under heating or catalysis results in a network structure, which is called polybenzoxazine (PBO), similar to that of phenolic resin . Because of the different structural characteristics of phenolic resin, benzoxazine maintains the advantages such as excellent hardness, heat resistance, inner flame retardancy, electrical insulation, and low cost of traditional phenolic resin, but also has a certain degree of toughness, relatively high char yields and near‐zero shrinkage upon polymerization of the monomers . Therefore, PBO is the most desirable material for preparing high‐strength and flame‐retardant aerogel thermal insulating materials.…”

Syntheses of Atypically Fluorinated Peptidyl Macrocycles through Sequential Vinylic Substitutions

“…However, relative to reagents 1 and 2 , we sought broader nucleophile participation and product geometries that are more compatible with smaller polyheterocyclic structures. Rather than aromatic substitutions, we choose to examine vinylic substitutions of fluoride from octafluorocyclopentene (OFCP, 3 ; Figure ) . Simple phenols, amines, mercaptans, and alcohols are known to displace fluoride from this commercial reagent, and the extent of substitution could be varied.…”

“…[6] Thee ase of fluoride ipso substitutions was appealing.H owever,r elative to reagents 1 and 2,wesought broader nucleophile participation and product geometries that are more compatible with smaller polyheterocyclic structures.R ather than aromatic substitutions,w ec hoose to examine vinylic substitutions of fluoride from octafluorocyclopentene (OFCP, 3; Figure 1). [7][8][9][10][11][12][13][14][15][16] Simple phenols, [7] amines, [10] mercaptans, [14,15] and alcohols [14][15][16] are known to displace fluoride from this commercial reagent, and the extent of substitution could be varied. Herein, we report that successive,d issymmetric substitutions [17] of fluoride on OFCP by functionalized peptides occurs readily,w hich provides af lexible means to generate constrained fluorinated macrocycles.…”