PSI - Issue 5

L. ALEXANDRESCU et al. / Procedia Structural Integrity 5 (2017) 675–682 Laurentia Alexandrescu/ Structural Integrity Procedia 00 (2017) 000 – 000

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spectrum. After the test were carried out, the following were fond :

1. The recorded spectrum for graphene oxide has absorptions at the following wavelengths: 1042 cm-1 which is specific for C-O (alkoxy) bonds, 1507 cm-1 specific CO (carboxy) absorption, 1603 cm-1 specific absorption for water absorbed by the powder, overlapping the vibrational band specific for the aromatic C = C bond, 1721 cm -1 carbon carbon (carboxyl) specific absorption, and the absorption band at 3157 cm -1 is specific for the hydrogen bonds of the OH groups from water adsorbed by the powder as well as those from COOH. 2. The IR spectrum recorded for polyamide (figure 8) shows absorption at the following wavelengths: 1190 cm 1 specific to CO-CH 2 bonds, 1275 cm -1 absorption specific to C-O (carboxy), 1567 cm -1 absorption specific to the NH group, 1633 cm -1 absorption specific to the C=C bond, and the absorption band at 3300 cm -1 is specific to C-N bonds. The overlapping spectra (figures 9,10) show the presence of PA and very weakly GO in compounds. The basic structural element of polyamide is the amide group (- CO-NH-), while for oxidized graphite, C-O, C=C and C=O, and absorptions for the two materials overlap in the spectra. The major presence of PA is seen from the intensity of characteristic peaks.

Figure 8. FT-IR spectrum from GO

Figure 9. FT-IR spectra from PP

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Figure 10. FT-IR spectra from PA

Figure 11. FT-IR spectra from GPP01

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Figure 12. FT-IR spectra from GPP01 – and GPP6- Figure 13. FT-IR spectra from GPP01 – and GPP10-

CONCLUSION - The paper presents the study of the new nanostructured polymer composites from polyamide/oxidized graphite nanoparticles-PA/GO to manufacture, by injection, bearing seals, contact plates, and other components for the railway industry, with shock resistance higher than 5-8 kJ/m², wear resistance below 100 mm 3 , resistance to temperatures of - 40 - 240 0 C, resistance to impact and to outdoor applications, with temperatures ranging from -40 to +60 0 C, in rain, snow or sunshine.