Effects of aramid fibers and colloidal particle fillers in composite ethylene propylene diene monomer rubber thermal insulators for rocket motor insulation

Abstract

In this study, we develop and characterize an asbestos-free rubber composite for potential use as a rocket motor insulator. The insulator is based on ethylene propylene diene monomer blended with aramid fiber (Kevlar) in the pulp form (KP), together with alumina and/or silica as reinforcement. Different formulations based on these fillers were prepared. The fillers were dispersed in the ethylene propylene diene monomer polymeric matrix to obtain a homogenous master batch for curing. We analyzed and compared physical, mechanical and thermal properties of different compositions (density, hardness, tensile strength, elongation, ablation resistance and mass loss on heating). Reinforcement of ethylene propylene diene monomer with Kevlar improves the performance of the material with respect to mechanical and thermal properties, while not improving well the performance with respect to ablation resistance. Using hybrid reinforcement (KP + alumina + silica) within ethylene propylene diene monomer improves the performance of ethylene propylene diene monomer with respect to mechanical properties, thermal properties, ablation resistance and thermal decomposition resistance. The optimum performance of the insulation material was achieved when the formulation consisted of 10 part per hundred ratio KP with even amounts of alumina and silica. A novel composite engineered for improved insulation of solid rocket motors using the hybrid reinforcements was developed for the first time, which can be applied in future space missions.

Properties of flame‐retardant TPU based on para‐aramid fiber modified with iron diethyl phosphinate

“…These deficiencies limit the application of halogen‐free flame retardants and intumescent flame retardants, so it is very necessary to find a new flame retardant with high flame retardancy and little environmental impact. As a new high‐tech synthetic fiber, para‐aramid fiber (AF) is developing rapidly in the field of composite materials . The flame‐retardant mechanism of para‐aramid fibers determined by its special chemical structure, which is different from that of other inorganic materials and halogenated compounds .…”

“…As a new high-tech synthetic fiber, para-aramid fiber (AF) is developing rapidly in the field of composite materials. 8,9 The flame-retardant mechanism of para-aramid fibers determined by its special chemical structure, which is different from that of other inorganic materials and halogenated compounds. [10][11][12][13][14] Therefore, it is a permanent flame-retardant fiber, which will not reduce or lose the flame retardancy due to the time of use.…”

Plastic packaging materials of laminated composites made of polymer cover sheets and a nonwoven interlayer

“…In this study, the flame resistance is improved with two factors. One factor is the addition and distribution of Kevlar fibers, which are flame retardants and beneficial in combustion resistance [30,31]. The other factor is the good interfacial adhesion, which reduces the void and air between the layers, thereby promoting flame resistance.…”

Evaluation of Ethylene Propylene Diene Terpolymer based insulation against Nitrile rubber based insulation for large Composite Rocket Motor Casing

“…Various studies have been carried out on the effect of aramid fiber, carbon fiber, hybrid reinforcement (Kevlar pulp+alumina+silica), Nanosilica, varying concentration of vulcanizing agent on the achieved properties/performance of EPDM insulator. [4][5][6][7][8][9][10][11] Literature is available on improving the interface bonding properties of EPDM insulator to propellant by incorporating and varying the concentration of CSE and HTPB based bonding agent and weakening of bond strength by absorbed water. 12,13 Study on vulcanization kinetics, ageing in water and thermal degradation behavior of EPDM insulator have also been reported.…”

“…Kevlar is used as one of the reinforcing fillers to improve the performance of EPDM with respect to mechanical and thermal properties. Various studies have been carried out on the effect of aramid fiber, carbon fiber, hybrid reinforcement (Kevlar pulp+alumina+silica), Nanosilica, varying concentration of vulcanizing agent on the achieved properties/performance of EPDM insulator 4‐11 . Literature is available on improving the interface bonding properties of EPDM insulator to propellant by incorporating and varying the concentration of CSE and HTPB based bonding agent and weakening of bond strength by absorbed water 12,13 .…”