PSI - Issue 45

Kentaro Yamauchi et al. / Procedia Structural Integrity 45 (2023) 125–131 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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(a) 0 vol.% egg white.

(b) 10 vol.% egg white.

(d) 40 vol.% egg white .

(c) 20 vol.% egg white.

(e) 50 vol.% egg white.

Fig. 3 The relationship between the adhesion strength F and surface free energy γs of the adherends.

A similar relationship was observed even when the epoxy resin adhesive was diluted by egg white up to 40 vol.%, as shown in Figs. 3(b), (c), and (d). In both cases of the epoxy resin and egg white infused epoxy resin, the lower limit of the linear relationship was observed as 15.3 mN/m, and F was constant in the region ranging from 2.3 to 15.3 mN/m. For the epoxy resin containing 50 vol.% egg white, a deviation from the linear relationship was observed as shown in Fig. 3 (e). The dependency of the adhesion strength on the egg white volume ratio is shown in Fig. 4. As can be seen from the figure, the adhesion strength increases from HIREC to PET, which corresponds to the order of the surface free energies of the adherends presented in Table 5. This indicates that the adhesion strength between the egg white infused