Epoxy resin matrix integrating epoxy‐polydimethylsiloxane based self‐healing microcapsules: Healing efficiency, mechanical and thermal stability

Abstract

Environmental factors such as climate change, temperature fluctuations, and mechanical forces hinder long-term space, transportation, and research missions due to structural damage. We report an innovative system to overcome this problem. The self-healing structure under examination is an epoxy as a polymeric matrix, which includes microcapsules embedded with epoxypolydimethylsiloxane (PDMS), as a healing agent, separately combined by microcapsules embedded with triethylenetetramine (TETA) as a hardener or curing agent. Scanning electron microscopy confirmed the presence and size of the microcapsules. It was shown that the rough appearance of microcapsules improves mechanical bonding. The diameter of microcapsules varied between 40 and 200 μm, with an average diameter of ~100 μm. The information of microcapsules and their structures were scrutinized through Fourier transformed infrared spectroscopy for chemical structure confirmation. It was determined that epoxy-PDMS practical liquids have been effectively encapsulated. The thermal performance of the microcapsules was investigated utilizing thermogravimetric analysis. The results showed that the microcapsules have thermal stability up to 220 C without degradation and decomposition. Additionally, the flexural test was used to evaluate the samples manually scratched with blade and compared with the pure epoxy sample. The results showed the sample containing 15% microcapsules has 105% recovery efficiency after 55 h.

Self‐healing polymers for aviation applications and their impact on circular economy

“…Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were utilized to examine the composition of the encapsulated therapeutic agent and their self-healing capabilities. 128 The aviation industry usages neat polymer only in limited components and therefore real benefit of selfhealing materials is possible only if promising results are seen in composites. The present state of research shows promising abilities to develop composites with good mechanical properties and adequate self-healing utilizing multimode self-healing technologies.…”

“…Microcapsules containing epoxy‐PDMS were polymerized via in situ polymerization in this study: (1) formation of the PUF and (2) encapsulation of epoxy‐PDMS. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were utilized to examine the composition of the encapsulated therapeutic agent and their self‐healing capabilities 128 …”

Effect of post‐curing temperature on the retention of mechanical strength of phthalonitrile thermosets and composites after a long‐term thermal oxidative aging

“…One of the characteristics of polymer materials significant for their application in structures operating at elevated temperatures is their thermal and thermal oxidative stability. [33][34][35][36][37][38] The most common method of thermal and thermal oxidative stability evaluation is non-isothermal TGA method corresponding to short-term stability 37,[39][40][41] but there are not a lot of works concerning long-term isothermal oxidative stability of phthalonitrile resins. 38,[42][43][44] The reported results of TGA studies revealed a valuable data related to the products of phthalonitriles degradation.…”

Improved tribological performance of epoxy composites containing core–shell PE wax@SiO2 nanoparticles

“…Epoxy resin (EP) is a widely used and indispensable thermosetting plastic for modern industry because of its excellent moldability, thermal, mechanical, anti-corrosion, and chemical resistant properties. [1][2][3] However, as a brittle polymer with three dimensions crosslinked structure inside, it lacks self-lubricating properties for being used in friction and wears protection. [4][5][6] To improve the lubricating and anti-wear properties of traditional epoxy resin, researchers have made great efforts, such as mixing lubricating secondary polymer (polytetrafluoroethylene (PTFE), [7,8] rubber, [9] polyurethane (PU) [10] ), incorporating anti-wear fillers (fibers [11][12][13] and inorganic particles [14,15] ) and doping nanofillers (nanosheets, [6,16,17] nanotubes [18,19] and nanoparticles [5,20] ) with both functions.…”