Thermal stability and decomposition kinetics of styrene-butadiene rubber nanocomposites filled with different particle sized kaolinites

• SBR/kaolinite composites are improved in thermal stability compared to pure SBR.
• Content of char decreases in residue as the increase of particle size of kaolinite.
• Thermal stability of composite reduces as the increase of kaolinite particle size.
• Raman spectrum is useful to determine the type of carbon in pyrolysis residues.

A series of styrene-butadiene rubber (SBR) nanocomposites filled with different particle sized kaolinites are prepared via a latex blending method. The thermal stabilities of these clay polymer nanocomposites (CPN) are characterized by a range of techniques including thermogravimetry (TG), digital photos, scanning electron microscopy (SEM) and Raman spectroscopy. These CPN show some remarkable improvement in thermal stability compared to that of the pure SBR. With the increase of kaolinite particle size, the residual char content and the average activation energy of kaolinite SBR nanocomposites all decrease; the pyrolysis residues become porous; the crystal carbon in the pyrolysis residues decrease significantly from 58.23% to 44.41%. The above results prove that the increase of kaolinite particle size is not beneficial in improving the thermal stability of kaolinite SBR nanocomposites.

The amorphous carbon (Cam) is increased with the increase of particle size of kaolinite, and the crystal carbon in four pyrolysis residues shows a reverse change tendency varying from 44.41% (FS-4) to 58.23% (FS-1). It displays that the increase in kaolinite particle size is not beneficial to form the crystalline carbon in the pyrolysis process.Fitting Raman spectra of the pyrolysis residues of SBR/kaolinite composites in region 1800–1000 cm− 1 at 550 °CFigure optionsDownload as PowerPoint slide