Effect of polyhedral oligomeric silsesquioxanes with different structures on dielectric and mechanical properties of epoxy resin

Abstract

Polyhedral oligomeric silsesquioxane (POSS) is a hybrid material composed of an organic substituent shell and inorganic skeleton core. To study the influence of different shells and cage‐shaped cores on dielectric and mechanical properties, four kinds of epoxy resin composites (EPs) fabricated with 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO), DOPO‐containing polyhedral oligomeric silsesquioxane (DOPOPOSS), octaphenyl polyhedral oligomeric silsesquioxane (OPS), and epoxy phenyl polyhedral oligomeric silsesquioxane (EPOSS) with the addition of 5 and 10 wt% were prepared, respectively. The dispersion, transparency, glass transition, dielectric, mechanical tensile, flexural, and impact properties of these epoxy resins were studied. Dielectric constant and loss of EPs were significantly reduced through introduction of three POSSs owing to their inherent hollow cores, and dielectric constant of the resins was further decreased with additional increase. Compared with three POSSs, DOPOPOSS had the best compatible shell, and its composites exhibited favorable transparency similar to pure EP and the obvious reduction in dielectric constant and loss, due to its nano‐dispersion in matrix. EPOSS was dispersed in a perfect spherical shape and uniformly embedded in matrix, and the composites showed good mechanical tensile, flexural, and impact strength. OPS was disorderly dispersed in resins, but its eight phenyl rings symmetrical shell had the advantage of nonpolar molecule structure, which endowed epoxy resin lower dielectric loss over the high‐frequency range (105–106 Hz). Compared with DOPOPOSS, DOPO was effective in reducing dielectric constant and loss of epoxy resin due to its reactive addition, however, it decreased the glass transition temperature, mechanical tensile, flexural, and impact strength of epoxy resin either.

High heat‐resistant (250°C) epoxy resin composites with excellent dielectric properties

“…In addition, according to our previous research that the POSS can introduce deep traps by react with epoxy when the filling ratio was 1%, as a result, the epoxy can possess higher DC breakdown strength, lower DC conductivity and better space charge suppression ability 18,19 . However, the enhance of heat resistance by POSS was not as obvious as dielectric properties 20,21 . This could be attributed to the lower filling ratio, and which can not meet the operating temperature of 250°C.…”

“…18,19 However, the enhance of heat resistance by POSS was not as obvious as dielectric properties. 20,21 This could be attributed to the lower filling ratio, and which can not meet the operating temperature of 250 C. Therefore, a filler which has well heat resistance is needed to cooperate with POSS once POSS is chosen to modify epoxy.…”

Synthesis, characterization, and properties of silicone grafted epoxy/acrylonitrile butadiene styrene/graphene oxide nanocomposite with high adhesion strength and thermal stability

“…[ 6–8 ] The application of silicone has gained increasing interests due to its oxidation and thermal stability. [ 9–12 ]…”

“…[6][7][8] The application of silicone has gained increasing interests due to its oxidation and thermal stability. [9][10][11][12] Bao and Cai [13] used methyl phenyl silicone (MPS) resin and a phosphorus compound named DOPO to improve the thermal properties of epoxy resins. They reported an 18% increase in char residue and 52% enhancement in limited oxygen index (LOI).…”

Epoxy resin/hollow glass microspheres composite materials with low dielectric constant and excellent mechanical performance

“…Recently, epoxy resin (EP) has aroused widely interest due to their high mechanical strength, low shrinkage, heat resistance, corrosion resistance and excellent electric properties, 1–3 which processes a wide range of applications like insulation material, adhesives in power equipment and electronic packaging, and so forth 4 . Nevertheless, with the rapid development of high‐tech electronic technology and microelectronics industry, the integration level of integrated circuit chips has been continuously improved, and the process size has been continuously reduced, which will increase the inter‐ and inter‐layer capacitances and wire resistances, thereby increasing the RC delay effect generated by wire resistance (R) and inter‐layer capacitance (C), resulting in a series of problems such as increased power loss, energy consumption, leakage current and signal distortion 5,6 .…”