Development of chopped glass fiber composites with difunctional benzoxazine and bio‐based phthalonitrile copolymer: A study of mechanical and thermomechanical properties

Abstract

The randomly-oriented glass fibers (GF) reinforced composites with Bisphenol A-amine based benzoxazine (BA-a) and bio-based eugenol-based phthalonitrile (EPN) copolymer were developed by an isothermal compression molding technique. The silane coupling agent-treated GF (TGF) reinforced composites showed much better impact strength as compared to as-received GF reinforced composites. A rise of 95.2 MPa, 5.5GPa, 69.1 MPa, and 2.5GPa in flexural strength, flexural modulus, tensile strength, and Young's modulus were observed, respectively. The DMA results confirmed that the storage modulus (E') and glass transition temperature (T g ) were gradually increased and the damping factor decreased as the TGF reinforcement was raised from 0 to 40 wt%. E' and T g values were 3.09 GPa and 27 C, respectively, higher than the recorded values for the neat copolymer. The 40 wt% TGF reinforced poly(BA-a/EPN) composite showed the maximum thermal stability values of 475.4, 507.3 C, and 75.43% for T 5 , T 10 , and Y c , respectively. The LOI values confirm that the TGF/copolymer composites have self-extinguishing properties.

Green composites from vanillin‐based benzoxazine: Modified almond shell particles, curing behavior, thermal stability, mechanical properties, and stress analysis

“…The LOI number was calculated to understand the material's flame‐resistant behavior. The literature shows excellent self‐extinguishing and flame‐retardant materials have an LOI value >26.40% 43,44 . Based on Y c from the TGA analysis, the LOI value was calculated using the Van Krevelan and Hofytzer (VKH) method as per Equation (). …”

Development of Hybrid Composite Utilizing Micro-Cellulose Fibers Extracted from Date Palm Rachis in the Najran Region

“…The inner layer SGF hybrid composite showed an additional rise of 25% and 13% in the tensile strength and Young’s modulus values, respectively, as compared to the recorded values for a traditional hybrid composite having SGF on the outer layers. Furthermore, in our earlier study, we evaluated chopped SGF composites with poly(BA-a/EPN) copolymer having the same composition [ 42 ]. The tensile strength and Young’s modulus of the SDPF/SGF sandwich structure were nearly 40 MPa and 2.5 GPa higher than the 40 wt.% chopped SGF reinforced composite.…”

“…Furthermore, the flexural properties of the hybrid composites were significantly higher than the various studied composites; i.e., 40 wt.% chopped GF reinforced in BA-a/EPN copolymer [ 42 ], 20 wt.% Kevlar Fiber reinforced in poly(BA-a) [ 43 ], and flax/basalt fibre laminates with epoxy resin [ 44 ]. However, the flexural strength and modulus were significantly lower than the flax/GF hybrid epoxy composites [ 17 ].…”

Vanillin- and Isovanillin-Based Phthalonitrile Resins Containing Spirocycle Acetal Structures

“…In addition, the narrow processing window caused by the high melting point of traditional PN monomers also limits its scope of application. 15 In recent years, biological and renewable raw materials such as plant oils, 16,17 cardanol, 18,19 lignin, 20−23 isosorbide, 24,25 furan, 26−28 itaconic acid, 29−31 and cellulose 32−34 have attracted increasing interest of researchers. Significant progress has been made in producing thermosets, especially epoxies and cyanate esters, from biobased resources.…”

“…Thus, it is imperative to develop innovative renewable raw materials. In addition, the narrow processing window caused by the high melting point of traditional PN monomers also limits its scope of application …”