Influence of the coupling agent and graphene oxide on the thermal and mechanical behavior of tea dust–polypropylene composites

Abstract

In this study, the effects of a coupling agent and additive on the physicomechanical (morphological, mechanical, thermal, and swelling) properties of tea dust (TD)–polypropylene (PP) composites were studied. TD–PP composites were prepared with untreated tea dust (UTD) and tetraethylsilane (TES)‐treated TD or silanated tea dust (STD) particles at ratios of 0:100, 10:90, 20:80, 30:70, and 40:60 w/w. Initially, TD particles were grafted by TES as a coupling agent, and these STD particles were then modified with graphene oxide (GO) as an additive to study their effects on the STD–PP composites; these were compared to the STD–PP and UTD–PP composites in accordance with a study of improvements in the mechanical properties. All of the TD–PP composites were analyzed with Fourier transform infrared spectroscopy, scanning electron microscopy, and mechanical, thermal, and physical tests. The thermal and mechanical properties of both the STD–PP and GO‐modified STD–PP composites were found to be improved as compared to those of the UTD–PP composites. So, the recycling of a large amount of TD as a waste material could be useful in the preparation of TD–PP composites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42927.

Elaboration of performance of tea dust–polypropylene composites

“…This treatment eliminated low molecular weight species and hemicelluloses . In previous study, FTIR spectra revealed that surface treatment of TD particles can remove hemicelluloses, lignin type materials and which was confirmed from the absence of spectra (1370–1330 cm −1 of in‐plane CH bending of hemicelluloses and 1505–1520 cm −1 for lignin) in treated TD particles. These TD particles were denoted as “styrene treated TD” (STD) particles.…”

“…Then PP composites were prepared by reinforcing the STD particles in matrix. Molecular mechanism and FTIR spectra of untreated and MA and tetra ethyl silane treated TD particles have been discussed . Surface treatment has been confirmed from XRD analysis.…”

“…Waste TD particles were collected from the tea stalls after use. TD is generally composed of moisture, ash, lignin, cellulose, and hemicellulose type materials …”

“…Compatibilizer and coupling agent normally enhance the compatibility of the two phases in polymer composites, for example, MA treated and silane treated TD:PP composites . Montecelli et al used different coupling agents for the treatment of fibers and reported that the degree of hydrolysis could enhance the bonding strength of the composite.…”

Physico‐mechanical properties of nano‐polystyrene‐decorated graphene oxide–epoxy composites

“…Therefore, graphene is a basic building block of graphitic materials having all dimensionalities and used in the synthesis of a variety of composite blend films and polymer nanocomposites. However, graphene sheets have a high specific surface area, and tend to form irreversible agglomerates or even restack to form graphite through van der Waals interactions . So, many scientists have prepared hybrid nanostructures of GO with different organic and inorganic materials to overcome this problem of GO.…”