Abstract:

This study investigated the effects of hyperbranched polyester （HBP H202 and H204） surface modification on carbon nanotubes （CNTs） and their subsequent impact on waterborne unsaturated polyester （WUPR） composites. Successful grafting was confirmed through FTIR， XRD， and XPS characterization. Comparative analysis indicated that while unmodified CNTs slightly enhanced WUPR's mechanical properties， HBP⁃modified CNTs （CNTs H202 and CNTs H204） demonstrated superior performance. Notably， CNTs H204 showed the most significant mechanical improvement. SEM analysis confirmed better CNT dispersion in WUPR after HBP modification. Friction tests indicated that modified CNTs substantially reduced mass wear compared to both pure WUPR and unmodified CNT composites. DMA test results showed enhanced storage modulus and glass transition temperature， with CNTs H202 exhibiting particularly strong interfacial interactions due to its smaller molecular size and higher grafting density. These findings demonstrated that HBP surface modification effectively improved CNT dispersion and interfacial bonding in WUPR， leading to superior composite performance. This work provides valuable insights for developing high⁃performance WUPR composites and broadening their industrial applications.

Key words: hyperbranched polyester, carbon nanotubes, waterborne unsaturated polyester, mechanical property, composite