Highly processable ternary systems based on benzoxazine, epoxy, and phenolic resins for carbon fiber composite processing

Abstract

Effects of resin compositions in ternary systems of benzoxazine, epoxy, and phenolic novolac resins on processability, and thermomechanical properties of their carbon fiber-reinforced composites are investigated. At suitable range of resin mass ratios, the ternary mixtures can provide a relatively wide processing window ranging from 50 to 200 C by maintaining their low A-stage viscosity for a relatively long time which is crucial in the fiber preimpregnating process. Furthermore, relatively long shelf-life of the ternary mixtures stored at room temperature ($ 30 C) up to 270 days is obtained with minimal effect on their processability. The optimum mass ratio of B : E : P was determined to be 3 : 6 : 2, i.e., BEP362 resin. Finally, the carbon fiber composite based on BEP362 was found to exhibit substantial enhancement in its mechanical properties.

Flammability and thermomechanical properties of dianhydride-modified polybenzoxazine composites reinforced with carbon fiber

“…One important group of polymeric composites is based on carbon fiber reinforcing systems which is often used in weight reduction and high specific strength requirement, i.e., aerospace, automotive, ballistic armor, or extreme sport applications. In addition, an improvement of polymeric material properties particularly by modification of the existing polymers to achieve high thermal properties, i.e., high char yield, and high glass transition temperature ( T g ) becomes increasingly important for an fiber‐reinforced polymer composites . Recently, the developed polybenzoxazine are a novel class of thermosetting polymers that combined the thermal properties and flame retardance of phenolic resin with mechanical performance and molecular design flexibility of epoxy resin.…”

“…However it decreases remarkably with CTBN content (∼380 MPa of 0 wt% CTBN to ∼200 MPa of 20 wt% CTBN). Furthermore, it is well known that the ability of benzoxazine resin to blend with other polymers or resins provides the resin with even broader range of applications . Rimdusit et al have reported that the carbon fiber (60 vol%)‐reinforced BEP362 copolymer also showed very high enhancement in its modulus value, i.e., storage modulus at 30°C equals to 57.5 GPa, while that of the neat BEP362 copolymer equals to 4.0 GPa.…”

“…Furthermore, it is well known that the ability of benzoxazine resin to blend with other polymers or resins provides the resin with even broader range of applications . Rimdusit et al have reported that the carbon fiber (60 vol%)‐reinforced BEP362 copolymer also showed very high enhancement in its modulus value, i.e., storage modulus at 30°C equals to 57.5 GPa, while that of the neat BEP362 copolymer equals to 4.0 GPa. Moreover, TDI‐based urethane prepolymer‐modified poly(BA‐a) reinforced with carbon fiber has been prepared by Rimdusit et al .…”

“…Rimdusit et al have reported that the carbon fiber (60 vol%)‐reinforced BEP362 copolymer also showed very high enhancement in its modulus value, i.e., storage modulus at 30°C equals to 57.5 GPa, while that of the neat BEP362 copolymer equals to 4.0 GPa. Moreover, TDI‐based urethane prepolymer‐modified poly(BA‐a) reinforced with carbon fiber has been prepared by Rimdusit et al . They found that the flexural strength of the carbon fiber‐reinforced BA‐a/PU = 60:40 weight ratio at 80 wt% of the carbon fiber in cross‐ply orientation provided relatively high values of about 490 MPa.…”

Developing Polybenzoxazine Composites Based on Various Carbon Structures

“…Toughness of PBZ resins can be enhanced by CF reinforcements . Nair and his coworkers investigated the mechanical strength and modulus of CFs‐reinforced PBZ composites by modifying the length of CFs.…”