Location: Bio-oils ResearchTitle: One-pot preparation of unsaturated polyester nanocomposites containing functionalized graphene sheets via a novel solvent-exchange method Author
|Liu, Zengshe - Kevin|
Submitted to: RSC Advances
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/20/2013
Publication Date: 10/25/2013
Publication URL: http://handle.nal.usda.gov/10113/60447
Citation: Liu, C., Wang, Z., Huang, Y., Xie, H., Liu, Z., Chen, Y., Lei, W., Hu, L., Zhou, Y., Cheng, R. 2013. One-pot preparation of unsaturated polyester nanocomposites containing functionalized graphene sheets via a novel solvent-exchange method. RSC Advances. 3:22830-22388. Interpretive Summary: Graphene was discovered in 2004 to show superior mechanical, thermal, and electrical properties. Fabricating nanocomposites of graphene with polymers has recently attracted additional attention because of the economies and advantageous properties of using graphene. The biggest challenge to that is how to incorporate graphene into polymer matrix to achieve single-layer graphene reinforced polymer. In this research, we discovered that graphene oxide (GO)/unsaturated polyester nanocomposites were fabricated by a one-pot method that integrates solvent-exchange method and in situ melt polycondensation. The analyses showed that GO nanosheets are finely dispersed in the polyester matrix and have strong interaction with the host polymer. This is significant because one layer GO alternate one layer host polymer with 0.32% GO will maximally increase tensile strength and modulus of this nanocomposite. These findings could benefit to their applications in aerospace, automobile and microelectronic industry.
Technical Abstract: This paper reports a convenient one-pot method integrating a novel solvent-exchange method into in situ melt polycondensation to fabricate unsaturated polyester nanocomposites containing functionalized graphene sheets (FGS). A novel solvent-exchange method was first developed to prepare graphene oxide/ethylene glycol (GO/EG) dispersions in a reactor equipped with a fractionating device. The prepared dispersions were applied successively to fabricate unsaturated polyester composites via in situ melt polycondensation in the same reactor. The dispersion behavior of GO/EG dispersions was characterized by atomic force microscopy (AFM). The structures and properties of the as-prepared FGS/polyester nanocomposites were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), tensile tests, thermogravimetric analysis, and dynamic mechanical analysis. The results of AFM show that GO nanosheets are well exfoliated in EG solvent. The results of FT-IR, XRD, Raman, SEM, and TEM indicate that the FGS are also finely exfoliated in the polyester matrix and have strong interaction with the host polymer. Compared with the neat UPR matrix, the composite with an extremely low content of 0.08 wt% FGS exhibits maximum increases of 53.6% and 48.4% in tensile strength and modulus; the composite with 0.32 wt% FGS has a 10.7 deg. C increase in thermal decomposition temperature and a 17.9 deg. C increase in glass transition temperature. Therefore, building on this work to generate unsaturated polyester nanocomposites with improved properties at reduced cost is possible.