Accession Number : ADA501811


Title :   High Temperature Epoxy Nanocomposites for Aerospace Applications


Descriptive Note : Final rept. 1 Apr 2006- 31 Mar 2009


Corporate Author : HOWARD UNIV WASHINGTON DC DEPT OF CHEMISTRY


Personal Author(s) : Raghavan, Dharmaraj ; Chenggang, Chen


Full Text : http://www.dtic.mil/get-tr-doc/pdf?AD=ADA501811


Report Date : 10 JUN 2009


Pagination or Media Count : 13


Abstract : The primary objective of this research is to make nanocomposites with the incorporation of thermally stable silicate nanolayers in the polymer matrix. Several functionalized imidazolium clays, functionalized anionic clays, and silylated apophylites were synthesized and characterized by XRD and TGA. Thermal studies of functionalized clay have shown that the onset decomposition temperature of imidazolium functionalized clay (>325 deg C), alpha amino napthononate exchanged layered double hydroxide (NLDH) (approx. 300 deg C), and covalently silylated apophyllite (approx. 420 deg C) can exceed the onset temperature of conventional organoclays (approx. 260 deg C). Chemorheological measurements of 2 wt% organoclay filled epoxy have shown that the processing window is pretty wide after the addition of the organic layered-silicate to epoxy resin. The thermal stability of epoxy seems to be influenced by the addition of clay and diluent used in the epoxy system. In many cases, higher char yield for nanocomposites was observed suggesting clay is serving as catalyst and acting as barrier in the decomposition of the epoxy matrix. We also studied the thermal stability of tetra functional epoxy nanocomposite and a consistent small improvement in the onset temperature of the nanocomposite was noticed.


Descriptors :   *NANOTECHNOLOGY , *EPOXY COMPOSITES , *CLAY , *SILICATES , AEROSPACE SYSTEMS , ORGANIC COMPOUNDS , RHEOLOGY , CATALYSTS , EPOXY RESINS , ANIONS , ION EXCHANGE , CHARRING , MATRIX MATERIALS , THERMAL STABILITY , X RAY DIFFRACTION , HIGH TEMPERATURE , SYNTHESIS(CHEMISTRY)


Subject Categories : LAMINATES AND COMPOSITE MATERIALS


Distribution Statement : APPROVED FOR PUBLIC RELEASE