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The purpose of this paper is to fabricate and characterize the natural fibre (NF) reinforced epoxy composites containing flame retardants (FRs) and microcrystalline cellulose (MCC) in terms of flammability, thermal properties and dynamic mechanical performances.

The FRs used in this study were ammonium polyphosphate and alumina trihydrate.

The results demonstrated that the addition of MCC particles into the flame retardant composite (control) further enhanced the self-extinguishing properties of composites, in particular, the burn length. Thermogravimetric analysis showed that the mass residue improved with every addition of MCC particles at 700 °C. For instance, the residual weight enhanced from 28.4 Wt.% to 33 Wt.% for the control and the composite with 7 Wt.% MCCs, respectively. As obtained from the dynamic mechanical analysis, the glass transition temperature of composites increased upon increasing inclusion of MCC particles. For example, this parameter was 77.1 °C and 86.8 °C for the control and composite loaded with 7 Wt.% MCC, respectively.

Thus, the combination of MCC and FR had been proved to be a promising flame retardant system for NF reinforced epoxy.

Electrospinning is a versatile technique for producing polymeric nanofibers by the application of electrostatic forces. The electrospinnability of polymeric solutions and the properties of electrospun nanofibers can be influenced and tuned by the process parameters. This paper aims to investigatethe influence of three key process parameters on the tensile strength of electrospun gelatin nanofibrous scaffold.

The experiments were conducted with a custom-built electrospinning system. Design of experiments of the three operating variables, namely, gelatin concentration, applied potential and feed rate, with five levels were investigated. Optimization of the tensile strength of electrospun gelatin scaffold was achieved with the aid of response surface methodology.

The resulting second-order mathematical models capable of demonstrating good correlation on the effects of the three identified process parameters with the experimental measured tensile strength, where the highest tensile strength was obtained on gelatin nanofibrous scaffold electrospun at 16per cent (w/v) gelatin concentration in acetic acid, 19 kV applied potential and 0.31 ml/h feed rate.

The resulting second-order mathematical models capable of demonstrating good correlation on the effects of the three identified process parameters with the experimental measured tensile strength, where the highest tensile strength was obtained on gelatin nanofibrous scaffold electrospun at 16per cent (w/v) gelatin concentration in acetic acid, 19 kV applied potential and 0.31 ml/h feed rate.

The study aimed to investigate epoxy composites reinforced with mechanical performances, thermal decomposition and ignitibility of natural fiber (NF) and doped with 5 wt.% of varying flame-retardant (FR) compounds. The incorporation of ammonium polyphosphate (APP) and zinc borate (ZB) showed improvement in modulus and elongation to break compared to the empty fruit bunch-filled epoxy (control). However, slightly lower tensile and impact strengths were recorded in all FR-containing composites.

Among the FR-loaded specimens, enhancement in flexural property was observed in composites with APP, whereas the addition of ZB and alumina trihydrate (ATH) resulted in the reduction of flexural strength. Thermogravimetric analysis results indicated that the introduction of APP and ATH negatively impacted the thermal degradation temperature (T_d) of the NF-filled composites. Greater mass residue with FR-filled composites, where increment was in the range from 32-80 per cent compared to the control, was observed, with the greatest being the ZB-containing formulation. Vertical Bunsen burner experiment revealed that the addition of ZB and APP led to a zero dripping flame system, whereas such a phenomenon was absent in both the control and NF composites loaded with ATH. The bomb calorimeter results revealed that addition of NF into neat epoxy significantly enhanced the FR behavior of the composite, and the gross heat of combustion was greatly reduced when FRs were incorporated into the control sample.

Results from the current study concluded that non-halogenated FRs including APP, ZB and ATH were able to enhance the fire retardancy of EFB epoxy composite without significantly deteriorate the mechanical behaviors.

It can be shown from scanning electron microscopy micrographs that the fabrication technique produced composites with good interfacial adhesion between NF and epoxy matrix, and homogenous distribution of FRs were achieved.