Thermal, thermoechanical and morphological behavior of Octa (maleimido phenyl) silsesquioxane (OMPS)-cyanate ester nanocomposites

Abstract

Polyhedral oligomeric silsesquioxane (POSS)-cyanate ester (CE) nanocomposites have been developed by the incorporation of octafunctional maleimide POSS (OMPS) into the bisphenol-A based CE network through in situ method by thermal curing with the use of diaminodiphenylmethane (DDM) as coupling agent. The formation of nanocomposite was confirmed by Fourier transform infrared analysis. X-ray diffraction, scanning electron microscopy and transmission electron microscopy images confirm the morphology of CE/OMPS nanocomposites. The thermal and morphological properties were studied by varying different weight percentages (1, 3, 5 and 10%) of OMPS. The 5 wt.% OMPS-incorporated nanocomposite possesses higher values of glass transition temperature than those of nanocomposites filled with a lower percentages of OMPS. Further thermal stability of nanocomposites increased with increase in percentage composition of OMPS.

Silicon-containing trifunctional and tetrafunctional cyanate esters: Synthesis, cure kinetics, and network properties

“…A strategy used to provide thermooxidative protection in cyanurate polymer networks that has been explored through much recent investigation is the incorporation of silicon or siloxy moieties in the form of monomers and cocuratives, blends and modifiers, silica nanoparticles, clay nanoplatelets, or other silicon‐containing nanostructures including oligomeric silsesquioxanes . While the addition of silicon in fully oxidized form (i.e., as SiO 2 ) can provide an in‐place barrier to oxygen permeation, the use of unoxidized organosilicon moieties or partly oxidized silicates allows for the in situ generation of a protective barrier during high‐temperature oxidation or exposure to energetic forms of oxygen (such as atomic oxygen in low Earth orbit) .…”

High-Temperature-Performance Cyanate Ester Composites with Carboranes

“…Hyperbranched polysiloxanes (POSS) have been widely known to improve thermal resistance properties through increased char formation by reducing the supply of combustible volatiles . Various functionalizations of POSS with octafunctional maleimide, epoxy, , and POSS–SiO 2 have been reported to improve the compatibility of these organic–inorganic hybrids in the CE matrix. It is evidenced in the literature that POSS improves the glass transition temperature ( T g ) and final char yield ( Y c ) of the CE composite with an increase in filler content of up to 10 wt %.…”