Curing kinetics and mechanical properties of cyanate ester/hyperbranched benzoxazine copolymers

Abstract

In the current study, three different curing kinetics models were used to analyze the curing kinetics of hyperbranched benzoxazine (HB‐PED230) and monofunctional benzoxazine (P‐a) modified cyanate ester (CE) resin by non‐isothermal differential scanning calorimeter. Moreover, the effects of two benzoxazines on the copolymerization behavior, thermal stability, and mechanical properties of CE resin were studied. Compared with the P‐a modified CE resin, HB‐PED230 greatly reduces the curing temperature of the copolymer, while improving the bending strength and impact strength. The curing temperature of HB‐PED230 modified CE resin was 79°C lower than neat CE resin, while the CE/P‐a blended resin only reduce 48°C. As the amount of HB‐PED230 increased, the flexural strength and flexural modulus of the copolymers were improved. Surprisingly, when 7 wt% of HB‐PED230 was added, the impact strength of the copolymer was increased by 177.6%, implying that the toughness of CE resin had been greatly improved. Moreover, the fracture morphology of the copolymers was observed by scanning electron microscope. In summary, a small amount of HB‐PED230 blending can effectively improve the overall performance of CE resin.

Improvement in the toughness and adhesive properties of cyanate ester resin by incorporation of fluorinated poly(aryl ether nitrile)

“…Additionally, as the amount of PFPEN increased, the exothermic peak associated with the curing process also shifted towards lower temperatures. This phenomenon can be attributed to the presence of a small quantity of terminal hydroxyl groups in PFPEN that promote the trimerization of the ACE resin 41 …”

Artificial neural network prediction of thermal and mechanical properties forBi2O3‐polybenzoxazinenanocomposites

“…To evaluate the mechanical resistance of the prepared samples, the 3‐point bending tests were performed because stress, strain, and bending modulus are parameters that measure material properties 68‐70 . Figure 10 shows the stress–strain bending curves of pure polybenzoxazine and composites filled with Bi 2 O 3 nanoparticles.…”

“…To evaluate the mechanical resistance of the prepared samples, the 3-point bending tests were performed because stress, strain, and bending modulus are parameters that measure material properties. [68][69][70] Figure 10 shows the stress-strain bending curves of pure polybenzoxazine and composites filled with Bi 2 O 3 nanoparticles. Experimental mechanical parameters derived from this figure, such as flexural stress, Young's modulus, elongation at break have been summarized in Table 3, for convenience and clarity.…”

Preparation of high‐performance hyperbranched polybenzoxazine with low dielectric constant

“…10 To further reduce the dielectric constant of polybenzoxazines, several measures could be taken, such as introducing low polarizability groups to diminish the overall polarizability of the material, 11,12 adding bulky groups to increase free volume, 13 increasing crosslinking density to restrain the orientation polarization of dipole, 14,15 and forming micropores structures inside the polymer. 16 Compared with traditional monofunctional and bifunctional polybenzoxazines, multifunctional polybenzoxazines usually exhibit higher mechanical property and thermal stability [17][18][19] due to the dense cross-linking networks. Xing et al 20 used resveratrol, propargylamine and paraformaldehyde to prepare a bio-based trifunctional polybenzoxazine with high thermal properties.…”

“…Compared with traditional monofunctional and bifunctional polybenzoxazines, multifunctional polybenzoxazines usually exhibit higher mechanical property and thermal stability 17–19 due to the dense cross‐linking networks. Xing et al 20 used resveratrol, propargylamine and paraformaldehyde to prepare a bio‐based trifunctional polybenzoxazine with high thermal properties.…”