Fit parameters of the Kraus model for composites C0–5.
| Sample | Silica surface functional groups |
 [MPa] |
 [MPa] |
γ c | 2m |
|---|---|---|---|---|---|
| C0a | Silanol | 6.79 | 3.37 | 24.00 ± 1.04 | 1.33 ± 0.08 |
| C1a,b | Alkyl | 5.40 | 3.35 | 32.56 ± 1.51 | 1.51 ± 0.23 |
| C2a,b | Imidazolium | 4.75 | 3.35 | 17.77 ± 1.13 | 1.13 ± 0.08 |
| C3b,c | Imidazolium | 3.99 | 3.34 | 5.42 ± 1.73 | 1.73 ± 0.22 |
| C4c,d | Alkyl | 5.75 | 3.35 | 20.80 ± 1.54 | 1.48 ± 0.18 |
| C5c,d | Imidazolium | 4.84 | 3.36 | 10.15 ± 0.36 | 1.57 ± 0.09 |
a
No change in surface functionality during compounding.
b
Ex situ particle silanization approach.
c
Change in surface functionality during compounding.
d
In situ particle silanization approach.