Study on Thermal Properties and Crystallization Behavior of Silica‐Modified Polyetheretherketone Composites

ABSTRACT This study employs KH560 to surface‐modify nano‐SiO 2 , which is then melt‐blended with PEEK to prepare composites with loadings of 0–7 phr. At 3 phr, the melting temperature rose to 348.5°C, the melting enthalpy reached a maximum of 80.33 J g −1 , and the corrected crystallinity remained comparable to that of pure PEEK, while the filler dispersion was the most uniform. Concurrently, the water contact angle decreased from 81.7° to 70.6°–72.8°, thermal conductivity increased substantially, and the dielectric breakdown strength nearly doubled, reaching ≈24.7 kV mm −1 at 5 phr. Compared with the higher loadings commonly reported in the literature, significant multi‐property improvements were achieved at only 3–5 phr. These results demonstrate that KH560 surface modification effectively enhances the thermal, crystallization, dielectric, and surface performance of PEEK at low filler contents.