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Graphical abstract Highlights • Formulation of PVDF/CuO/Al is optimized on the basis of maximum heat of reaction. • Electrospinning is employed to fabricate high solid-loading MICs based on PVDF. • Electrospinning and doping of GO can improve the density, heat of reaction, etc. Abstract In this paper, the electrospinning technique has been employed to fabricate PVDF/CuO/Al nanocomposites, where the formulation was optimized on the basis of maximizing the reaction heat with increased efficiency. The graphene oxide (GO) has also been used as both lubricant and catalyst, which is well dispersed inside the PVDF matrix by the electrospinning process as well. It has been found that the smooth PVDF nano-fibers could be fabricated with GO content of 0.5 wt%, where the Al and CuO nanoparticles are also uniformly loaded. In comparison with the n-CuO/n-Al and PVDF/CuO/Al prepared by conventional mechanical mixing method, the GO-doped PVDF/CuO/Al nanocomposites via electrospinning improved heat of reaction, density as well as anti-oxidation capability. In addition, the electrospinning technique and doping of 0.5 wt% of GO can improve the reaction efficiency of PVDF/CuO/Al nanocomposites since they contribute to dispersion of components and homogeneous structure fabrication. [ABSTRACT FROM AUTHOR]

• Composite propellants (CPs) containing insensitive high-energy qy-HMX have been prepared. • The qy-HMX-based CPs has 9.64% higher heat of explosion than HMX-based one. • The burn rate of CPs containing qy-HMX is 4.38 mm·s−1 at 3 MPa, 45.9% lower than that of corresponding HMX-based one. • The average particle size of the CCPs of qy-HMX-based CPs is 71.5% lower than that of HMX-based one. Two types of qy-HMX (insensitive HMX with improved energy density, numbered 1 and 2) have been used and studied as an ingredient of HTPB-based composite propellants (CPs), and the decomposition and combustion performances have been investigated. It has been shown that the main exothermic peak temperature of blank CPs containing 21 wt% of qy-HMX-1 is 258.9 °C, which is 4.7 °C higher than that of HMX-containing one, indicating improved thermostability. The corresponding heat of explosion for blank qy-HMX-2-based CPs was measured to be 5830 J∙g−1, which is 300 J∙g−1 higher than that of HMX-based one. Interestingly, the qy-HMX-2-based CPs has higher energy density than corresponding CL-20-based ones, but it has much lower burn rate under the same pressure, e.g. 4.38 mm∙s−1 at 3 MPa for the former vs. 9.03 mm∙s−1 for the latter. Under the effect of typical conventional catalysts such as nano-CuO and nano-Fe 2 O 3 , the qy-HMX-1-based CPs showed increased heat of explosion and higher burn rate. In addition, the particle sizes of condensed combustion products (CCPs) of CPs containing qy-HMX-2 are much smaller than that of HMX-based one, where the Al 4 C 3 was produced as its unique CCPs ingredient. [ABSTRACT FROM AUTHOR]