Effect of non-functionalized and functionalized graphene oxide with a silane agent on the thermal and rheological properties of nylon 6,6

• Published in: Iranian polymer journal 2023-02, Vol.32 (2), p.139-149
• Main Authors: Torres-Castillo, Cristina S., Fuentes-Agustín, José E., García-Reyes, Eric M., Zamudio-Aguilar, Minerva A. M., Morales-Zamudio, Luisiana, Lozano, Tomas, Navarro-Pardo, Fabiola, Sanchez-Valdez, Saúl, Martinez-Colunga, Guillermo, Karami, Sahir, Lafleur, Pierre
• Format: Article
• Language: English
• Subjects: Ceramics; Chemistry; Chemistry and Materials Science; Composites; Dynamic mechanical analysis; Fourier transforms; Glass; Glass transition temperature; Graphene; Infrared spectroscopy; Loss modulus; Nanocomposites; Natural Materials; Nylon 66; Original Research; Photoelectrons; Polymer Sciences; Raman spectroscopy; Reaction mechanisms; Rheological properties; Rheology; Sheets; Silanes; Spectrum analysis; Storage modulus; Synthesis; X ray photoelectron spectroscopy
• ISSN: 1026-1265; 1735-5265
• DOI: 10.1007/s13726-022-01110-3

In this work, graphene oxide has been synthesized and functionalized with a silane agent to improve the interactions with nylon 6,6. The functionalization reactions for graphene oxide (GO) resulted in a different way as expected, a heteroatom was grafted into graphene hexagonal network, which led to a new route of chemical modification of graphene oxide sheets. The nanocomposites were obtained by a two-step extrusion process where the content of the nanofiller was of 0.30, 0.60, and 0.90 wt%, respectively. Subsequently, the composites were rheologically and thermally tested. Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) techniques were used to characterize the synthesized and functionalized graphene oxide. The composites were evaluated by dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC) methods. The results showed that graphene oxide acted as a nucleating agent, increasing the crystallinity and glass transition temperature of composites. An increment in rheological properties was also recorded, mainly in the loss and storage modulus of the composites. The obtained values of loss modulus of composite samples with functionalized GO (GOAPTS) were higher than those obtained for composites with unfunctionalized GO. The highest value of the storage modulus was for the composite sample with a content of 0.6 wt% of GOAPTS. A new reaction mechanism was detected between graphene oxide and 3-aminopropyl trimethoxysilane (APTS) forming pyridinium and pyridone on the graphene oxide sheets. Graphical Abstract