Nanocomposites and nanomaterials

Thermodestruction of hybrid composites 
with microspheres coated with semiconductor and dielectric 

Sigareva N.V.1, Mykytyn I.M.2, Myroniuk I.F.2, 
Gorelov B.M.1, Mishchenko V.M.1, Starokadomskiy D.L.1

1Chuiko Institute of Surface Chemistry NAS of Ukraine. Gen. Naumova, 17, Kyiv ‒ 03164, Ukraine. E-mail: microft2@ukr.net;

2Vasyl Stefanyk Precarpathian National University, 57, st. Shevchenko, Ivano-Frankivsk 76000; E-mail: myrif555@gmail.com

The thermal destruction of composites based on Epoxy 520 epoxy resin, filled with microspheres of crystalline silicon dioxide with magnetite content, and the same microspheres covered with SnO2 shell in dielectric and conductive phases have been investigated. In composites a particle content was 1.5% by weight. In conductive and dielectric phases the SnO2 concentration on the surface of the microspheres was respectively 1.5 and 2.5%. The shell thickness was 3-4 μm. 
Experimental investigations were performed by the method of temperature-programmable desorption mass spectrometry in the temperature range 25-800 oC. The heating rate was 8 oC/min. Atomic desorption products were recorded in the m/z range 15-180 (m is the fragment mass, z is the fragment charge). 
It was established that the encapsulation of microspheres in the conductive SnO2 shell increases the thermal stability of composites and decreases the intensity of fragment desorption by 3-9 times. The coverage of microspheres in the dielectric SnO2 give rises an increase in the thermal degradation of composites (Fig. 1).

Fig.1. Desorption curves for destruction fragment with m/z 42 (a) and 94 (b)  for epoxy resin (1) and its composites filled with 1,5 % microspheres (2), microspheres covered in the conductor (3) and insulator (4).