Fig. 3: Water vapor annealing enhanced the mechanical properties and structural stability of the SFMA microgroove coating.

a FTIR spectra of SFMA microgroove coating subjected to water vapor annealing treatment with different time. b Magnified view of the amide I region in (a) FTIR spectra. c Representative spectra at different water vapor annealing times after peak fitting. d Conformation contents in the amide I region of the SFMA microgroove coating at different water vapor annealing times. e Rheological curves of SFMA microgroove coating before and after 2 min water vapor annealing. f Quantitative analysis of storage modulus and loss angle of SFMA microgroove coating before and after 2 min water vapor annealing. g Tensile stress-strain curves of SFMA microgroove coating before and after 2 min water vapor annealing. h Quantitative analysis of toughness and modulus of SFMA microgroove coating before and after 2 min water vapor annealing. i Optical images of SFMA microgroove coating without and after 2 min water vapor annealing immersed in PBS solution after different time lengths. j Schematic illustration of the anti-swelling mechanism of the SFMA microgroove coating without and after 2 min water vapor annealing. Values in (d, f, h) represent the mean ± SD (three independent replicates (n = 3) for d and four independent replicates (n = 4) for (f and h). Statistical difference was determined by two-tailed unpaired Student’s T-test between two groups. One-way analysis of variance (ANOVA) with a Tukey’s post hoc test was used for multiple comparisons. Source data and exact P values are provided as a Source data file. (ns: P > 0.05, *P < 0.05, **P < 0.01, ***P < 0.001).