Comparative study between UVB 313 nm, UVC 254 nm, and far UVC 222 nm light on the aging of polyamide 66
Abel Hurtado Macias,
M. Román-Aguirre,
R.P. Talamantes,
Karen M. Soto,
José Luis Reyes Araiza,
Nestor Méndez-Lozano,
Miguel Apátiga-Castro,
Jorge Pineda-Piñón,
José Ramon Gasca Tirado,
José M. López-Romero,
A. Manzano-Ramírez
Affiliations
Abel Hurtado Macias
Department of Metallurgy and Structural Integrity, National Nanotechnology Laboratory Centro de Investigación en Materiales Avanzados S.C, Chihuahua, Chihuahua Mexico
M. Román-Aguirre
Department of Engineering and Chemistry of Materials, National Nanotechnology Laboratory Centro de Investigación en Materiales Avanzados S.C, Chihuahua, Chihuahua Mexico; Corresponding author.
R.P. Talamantes
Department of Engineering and Chemistry of Materials, National Nanotechnology Laboratory Centro de Investigación en Materiales Avanzados S.C, Chihuahua, Chihuahua Mexico
Karen M. Soto
Centro de Investigaciones y de Estudios Avanzados Del I.P.N. Unidad Querétaro, Querétaro, Querétaro, C.P. 76230, Mexico
José Luis Reyes Araiza
Facultad de Ingeniería, Universidad Autónoma de Querétaro, Centro Universitario, Cerro de Las Campanas S/n, C.P. 76010, Querétaro, Querétaro, Mexico
Nestor Méndez-Lozano
Universidad Del Valle de México, Campus Querétaro, Blvd. Juriquilla no. 1000 A Del. Santa Rosa Jáuregui, C.P. 76230, Querétaro, Qro., Mexico
Miguel Apátiga-Castro
Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, A.P. 1-1010, C.P. 76000, Querétaro, Qro., Mexico
Jorge Pineda-Piñón
Instituto Politécnico Nacional, Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada, Unidad Querétaro, Cerro Blanco No. 141, Colinas Del Cimatario, Querétaro, 76090, Qro, Mexico
José Ramon Gasca Tirado
Departamento de Ingeniería, Universidad de Guanajuato. Guanajuato, C.P. 36000, Mexico
José M. López-Romero
Centro de Investigaciones y de Estudios Avanzados Del I.P.N. Unidad Querétaro, Querétaro, Querétaro, C.P. 76230, Mexico
A. Manzano-Ramírez
Centro de Investigaciones y de Estudios Avanzados Del I.P.N. Unidad Querétaro, Querétaro, Querétaro, C.P. 76230, Mexico; Corresponding author.
Polyamide-66 underwent substantial growth worldwide in the late 1930′s. It can be found in several public spaces. After 2019, due to the coronavirus disease (COVID-19), the sanitization of the interior of aircraft and public spaces by using UV light became important. Most of all, the effect of the far UVC 222 nm became a research hot spot and is still a research blank. In the present work, a comparative study on the post-exposure damage of polyamide- 66 occurred when controlled ultraviolet irradiation (UVC 254 nm, far UVC 222 nm, UVB 310 nm) and moisture-condensation were carried out. Chemical (FTIR), thermal (DMA), and nano-mechanical properties were evaluated. FTIR analysis showed the formation of O-H and/or N-H bonds since there appeared absorptions at 3400 cm−1 along with the vanishing of other signals related to C-N bonding. These changes are more evident in samples exposed to UVC 254 nm followed by samples that were irradiated with UVC 222 nm. Samples that were aged with UVA 313 nm didn't show a change in FTIR spectra. FTIR on spectra and nanoindentation showed that UVB 313 nm produced a lower aging effect on this material. In contrast, UVC 254 nm light caused the highest degree of surface chemical-mechanical change attributed to cleavage/crosslinking reactions initiated by free radicals produced by UV light and moisture. On the contrary, far UVC 222 nm light presented moderate effects on Polyamide-66. Glass-transition temperature (Tg) diminished as the time to exposure increased attributed to water absorption and surface damage, being the highest change at −16.05 °C for samples irradiated with 245 UVC nm. However, the potential of far UVC 222 nm light for COVID-19 sanitization, with no significant degradation effects on polymeric materials, is a promising finding that should be further explored and could provide a hopeful solution in the fight against the pandemic.
