Small-angle X-ray scattering (SAXS) provides information about the phase-separated morphology of APCNs. The position of the main peak (q*) in the SAXS traces allows determining the dspacing, i.e., the average distance of the scattering domains (Figure ). The CNCs in the APCN matrix had minimal influence on the domain size and phase separation. The WAXS results, Figure , show peaks at 2θ ≈ 12° and 22° corresponding to the PDMS and PHEA phases, respectively. The peptides form β-sheets, which result in a WAXS peak at 2θ ≈ 5° (q = 0.36 Å -1 ) observable in all the investigated peptidic APCNs. Moreover, the ATR-FTIR spectra reveal βsheet peaks for all the samples ( Figure ). Thus, the presence of CNCs did not impact the formation of peptide β-sheets. With increasing HCNC content, starting from 3 wt%, a WAXS peak at 2θ ≈ 8° emerged and became stronger through to 22 wt%. The peak from the PDMS at 2θ ≈ 12° also changes, becoming broader with 2 smaller peaks appearing at higher CNC concentrations. This observation confirms the presence of the HCNCs in the APCNs, as the crystalline microstructure of the CNCs results in two peaks at 2θ ≈ 4.5° and 16.5°. However, due to the PDMS peak, peak shifting may occur.