Impacts of hemp fiber diameter on mechanical and water uptake properties of polybenzoxazine composites

Dayo, Abdul Qadeer; Wang, An-ran; Kiran, S.; Wang, Jun; Qureshi, Khadija; Xu, Yi-le; Zegaoui, Abdeldjalil; Derradji, Mehdi; Liu, Wenbin

doi:10.1016/j.indcrop.2017.10.039

Cited by 39 publications

(14 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Qiu 1 , C-M. Liu 1* have been studied [30][31][32][33][34]. However, most benzoxazine resins appear as high melting point powders, and organic solvents [35] are always needed when preparing benzoxazine composites. Obviously, organic solvent will bring about environmental issues and make the process complicated.…”

Section: Introductionmentioning

confidence: 99%

Low melting point, high thermal stable branched benzoxazines resin derived from mixed-substituted phosphazene core

Ma¹,

Qiu²,

Liu³

2020

Express Polym. Lett.

View full text Add to dashboard Cite

Six fluorine-containing, mix-substituted phosphazene-based branched benzoxazine monomers with a low melting point were successfully prepared and their chemical structures were verified by 1 H, 13 C, 31 P and 19 F nuclear magnetic resonance (NMR). These branched benzoxazine resins underwent thermal ring-opening polymerization to form cured polymers with high thermal stability both in N 2 atmosphere and in air. The co-substituents, both m-CF 3 PhOH and p-CF 3 PhOH, imposed significant effects on processing, thermal, and surface properties of corresponding polybenzoxazines. Non-isothermal differential scanning calorimetry (DSC) under diverse heating rates was adopted to investigate the curing kinetics and determine the activation energy of polymerization. DSC results indicate that the m-CF 3 PhO-/p-CF 3 PhO-groups have the potential to lower ring-opening polymerization temperature. Glass transition temperatures (T g s) of polybenzoxazines derived from p-CF 3 PhOH are higher than that of polymers derived from m-CF 3 PhOH due to different steric hindrance and crosslinking density. More interesting, all polybenzoxazines show relatively high dielectric constant but exhibit low dielectric loss at ambient temperature.

show abstract

Section: Introductionmentioning

confidence: 99%

Low melting point, high thermal stable branched benzoxazines resin derived from mixed-substituted phosphazene core

Ma¹,

Qiu²,

Liu³

2020

Express Polym. Lett.

View full text Add to dashboard Cite

show abstract

“…In addition, loads are allowed to efficiently transfer from matrix to fibers when the fiber content increases, leading to an enhancement of composite mechanical performance. Dayo et al reported that decreasing the fiber diameter could enhance the composite tensile properties, which was attributed by the preferable interfacial adhesion and the improved available fiber‐resin surface. However, it is found that there is a slight decrease in the composite strength when the fiber volume fraction exceeds 70%.…”

Section: Resultsmentioning

confidence: 99%

Thermal and mechanical performance of unidirectional composites from bamboo fibers with varying volume fractions

et al. 2019

View full text Add to dashboard Cite

In this work, a simple hand lay-up technique was employed to fabricate bamboo fiber reinforced epoxy resin composites, and subsequently composites with different fiber volume fractions (0%, 30%, 50%, and 70%) were prepared. To investigate the composite thermal properties, differential scanning calorimetry (DSC), thermogravimetric (TG) analysis, and dynamic mechanical analysis (DMA) were used. DSC demonstrates a decrease of glass transition temperature when fibers are incorporated into epoxy resin. TG results reveal that the degradation temperature increases with increasing the fiber content, and then a better thermal stability is achieved. The thermal results indicate that bamboo fibers provide a good resistance for heat insulation, suppressing the epoxy thermal decomposition. DMA shows that both storage modulus and loss modulus increase with increasing the fiber volume fraction in the temperature range of 30-200 C. Tensile tests and scanning electron microscopy (SEM) were also conducted on the specimens to investigate the material mechanical behavior. Compared with epoxy resin, the composites incorporated with bamboo fibers exhibit an improved tensile strength and modulus. The detailed analysis reveals that bamboo fibers have a positive effect on the thermo-mechanical properties of epoxy resin, providing a feasibility to using natural composites in a specific construction. POLYM. COMPOS., 40:3929-3937, 2019.

show abstract

“…Besides, the performance of the phthalonitrile resins to the gamma rays radiation and shielding resistances has also been confirmed . Similar to phthalonitrile‐containing polymers, benzoxazine resins can also be applied to obtain high‐performance materials . Copolymerization of benzoxazine/phthalonitrile has been studied and the prepared copolymers can be used as high‐performance matrix in various fields .…”

Section: Introductionmentioning

confidence: 91%

Modification of Solventless‐Synthesized Benzoxazine Resin by Phthalonitrile Group: An Effective Approach for Enhancing Thermal Stability of Polybenzoxazines

Liu

Yin

et al. 2018

Macro Chemistry & Physics

View full text Add to dashboard Cite

Although the solventless method for synthesizing benzoxazine resins has the advantage of low cost, the impurities involved in the products such as oligomers and original phenols significantly weaken the properties of polybenzoxazines. Herein, the commercialized BA‐a (benzoxazine derived from bisphenol‐A, aniline, and formaldehyde) resin obtained from a solventless method is modified by phthalonitrile through the reaction between phenol groups and 4‐nitrophtahlonitrile. The structures of obtained resins have been confirmed by 1H and 13C nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR). In addition, the ring‐opening polymerization behavior of each resin has been studied by differential scanning calorimetry and in situ FTIR. Furthermore, the thermal properties of the cross‐linked thermosets were measured by thermomechanical analysis and thermogravimetric analysis. The phthalonitrile‐functionalized benzoxazine resin shows a low polymerization temperature with the maximum of exothermic peak centered at 218.7 °C, and its corresponding polybenzoxazine exhibits excellent thermal stability, with a high Td5 value (346 °C) and high char yield (42.78%).

show abstract

Impacts of hemp fiber diameter on mechanical and water uptake properties of polybenzoxazine composites

Cited by 39 publications

References 39 publications

Low melting point, high thermal stable branched benzoxazines resin derived from mixed-substituted phosphazene core

Low melting point, high thermal stable branched benzoxazines resin derived from mixed-substituted phosphazene core

Thermal and mechanical performance of unidirectional composites from bamboo fibers with varying volume fractions

Modification of Solventless‐Synthesized Benzoxazine Resin by Phthalonitrile Group: An Effective Approach for Enhancing Thermal Stability of Polybenzoxazines

Contact Info

Product

Resources

About