Stress Relaxation Behavior of Azido Propellant Based on BAMO-THF at High Temperatures.

The azido propellant, with high energy and low signature, has been a hotpot in the field of propellants. However, the risk of low heat resistance and mechanical performance restricts their range of applications in high-energy formulations. In this study, four azido propellants based on 3,3-bis (azidomethyl) oxetane-tetrahydrofuran copolyether (BAMO-THF) have been prepared, their basic physical properties including energetic properties, internal micro-structure and true density were studied; their tensile properties, dynamic mechanical performances, were investigated, the structure-properties relationship was proposed.

Molecular dynamics study on the physical compatibility of SEBS/plasticizer blend systems.

Context: Thermoplastic elastomer styrene-ethylene-butylene-styrene block copolymer (SEBS) has excellent mechanical properties and aging resistance, so it has good application prospects in thermoplastic solid propellants. The selection of plasticizer is one of the keys to the formulation design of thermoplastic solid propellant. The compatibility of the plasticizer with the polymer determines the plasticizer's ability to plasticize the polymer's molecular chain segments.

Structure and Properties of Epoxy Resin/Graphene Oxide Composites Prepared from Silicon Dioxide-Modified Graphene Oxide.

In this study, graphene oxide (GO) was modified via electrostatic interactions and chemical grafting by silica (SiO), and two SiO@GO hybrids (GO-A and GO-B, respectively) with different structures were obtained and carefully characterized. Results confirmed the successful grafting of SiO onto the GO surface using both strategies. The distribution of SiO particles on the surface of GO-A was denser and more agglomerated, while it was more uniform on the surface of GO-B.

In Situ Interfacial Polymerized Arginine-Doped Polydopamine Thin-Film Nanocomposite Membranes for High-Separation and Antifouling Reverse Osmosis.

In this work, we synthesized polydopamine nanoparticles (PDNPs-M, M = I, II, III, and IV) with uniform particle sizes but varying l-arginine (Arg) contents (0%, 0.53%, 3.73%, and 6.

Investigation on Nanocomposites of Polysulfone and Different Ratios of Graphene Oxide with Structural Defects Repaired by Cellulose Nanocrystals.

In this manuscript, nanofillers of graphene oxide (GO) and cellulose nanocrystal (CNC) with different weight ratios (G/C ratios), named GC 2:1, GC 4:1, GC 8:1, GC 16:1, and GC 32:1, were successfully prepared. Characterization methods such as Raman spectroscopy, X-ray photoelectron spectrometry (XPS), and thermogravimetric analysis (TGA) were performed. Additionally, the effects of these samples on the thermal stability, mechanical properties, and gas barrier properties of polysulfone (PSF) nanocomposites were investigated.

A Full Range Experimental Study of Amplitude- and Frequency-Dependent Characteristics of Rubber Springs.

This paper provides a comprehensive understanding of the amplitude- and frequency-dependent characteristics of rubber springs. The dynamic nonlinear inelasticity of rubber is a key academic problem for continuum mechanics and a bottleneck problem for the practical use of rubber structures. Despite intensive efforts witnessed in industrial applications, it still demands an unambiguous constitutive model for dynamic nonlinear inelasticity, which is known as the Payne effect.

Effects of Silicon Dioxide/Graphene Oxide Hybrid Modification on Curing Kinetics of Epoxy Resin.

In this study, SiO-grafted graphene oxide (GO-SiO) was prepared using the oxygen-containing group on the GO surface as the active site of the reaction. The chemical structure, morphology, and particle size of GO and GO-SiO were carefully investigated by Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), Raman spectroscopy, thermogravimetry, transmission electron microscopy, scanning electron microscopy, and atomic force microscopy, and the results proved that the grafting modification was successful. Furthermore, epoxy (EP)/GO composites were prepared, and the effects of unmodified GO and GO-SiO on the curing kinetics of EP were comparatively studied by differential scanning calorimetry (DSC).

Evaluation of Blend Uniformity and Terminal Point during Continuous Mixing in Water for Modified Double-Base Propellant Components Using a Near-Infrared Method.

A near-infrared (NIR) spectrometer was used to test the double-base absorbent powder sample and to quantitatively analyze the contents of each component as well as their dispersion uniformity to establish a rapid quantitative test method for blending uniformity of modified double-base (MDB) propellant components. First, the quantitative calibration models of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) were constructed based on sample testing, and the RDX model's correlation coefficient was 0.9929.

Investigation on the Effects of MXene and β-Nucleating Agent on the Crystallization Behavior of Isotactic Polypropylene.

The effects of MXene on the crystallization behavior of β-nucleated isotactic polypropylene (iPP) were comparatively studied. The commonly used MXene TiCT was prepared by selective etching and its structure and morphology were studied in detail. Then MXene and a rare earth β-nucleating agent (NA) WBG-II were nucleated with iPP to prepare samples with different polymorphic compositions.

Effects of Hyperbranched Polyester-Modified Carbon Nanotubes on the Crystallization Kinetics of Polylactic Acid.

Poly-l-lactic acid (PLLA) is a prospective renewable and degradable material, but slow crystallization limits its processing and application. By dehydration condensation of hydroxyl-terminated hyperbranched resin (H202) and carboxylated carbon nanotubes (CNTs), a modified CNT, CNTs-H202, was obtained. Grafting was confirmed by Fourier transform infrared (FTIR) spectroscopy, and the grafting content was assessed by thermogravimetric analysis (TGA).

Zeolitic imidazolate framework-67 for shape stabilization and enhanced thermal stability of paraffin-based phase change materials.

Zeolitic imidazolate framework-67 (ZIF-67), a new kind of metal-organic framework, has large surface area as well as outstanding thermal and chemical stability. In this paper, micro-sized ZIF-67 crystals were prepared and further employed as the reinforcing material to design novel paraffin-based composite phase change materials (PCMs) with a polymethyl methacrylate (PMMA) shell. The composite PCMs were fabricated by using a ZIF-67 crystal-stabilized oil-in-water (O/W) Pickering emulsion as a template.