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Gallic acid is a renewable plant phenolic resource, and the polyphenolic bio‐based epoxy resin prepared from it can be used as a substitute for bisphenol A epoxy resin in certain fields. However, bio‐based epoxy resins used in the field of high‐performance composite material matrices often require modification. In this paper, firstly, γ‐(2,3‐epoxypropoxy)propyl trimethoxysilane (KH560) was used as the raw material to prepare epoxy‐based cage silsesquioxanes (E‐POSS). Then, E‐POSS was grafted onto γ‐aminopropyltriethoxysilane (KH550) modified halloysite nanotubes (m‐HNTs) to prepare a novel hybrid nanoparticle HNTs‐e‐POSS. Experimental analysis shows that ring opening reactions of amino and epoxy groups can occur between m‐HNTs and E‐POSS, forming a hybrid nanoparticle system of POSS aggregates on the surface of HNTs. Bio‐based nanocomposites were prepared by adding different mass fractions of hybrid nanoparticles HNTs‐e‐POSS into polyphenol type gallic acid epoxy resin matrix (GAER) and using methyltetrahydrophthalic anhydride as curing agent. The properties and micromorphology of the composite were analyzed and characterized. The research showed that with the addition of HNTs‐e‐POSS nanoparticles, the strength and toughness of the composite resin system show a pattern of first increasing and then decreasing, while the storage modulus(E′), glass transition temperature (Tg), and thermal stability of the composite material increased. Mechanical performance analysis shows that the introduction of 0.5 wt% HNTs‐e‐POSS would increase the tensile strength of the composite by 25.46%, while adding 0.75 wt% HNTs‐e‐POSS can increase the impact strength by 15%. The E′(30°C) increased by 24.2% and Tg increased by 7.7°C when the HNTs‐e‐POSS addition was 0.25 wt%. Highlights: Prepared hybrid nanoparticle HNTs‐e‐POSS by grafting POSS onto the HNTs surface.Application of HNTs‐e‐POSS in modification of bio‐based gallic acid epoxy resin.HNTs‐e‐POSS can co‐cured with epoxy matrix to increase the crosslinking degree.The strength, toughness, and modulus of gallic acid epoxy resin are improved.Tg and thermal stability of gallic acid epoxy resin are enhanced. [ABSTRACT FROM AUTHOR]

KH550 modified halloysite nanotubes (m‐HNTs) were hybridized with sulfoxide chloride acylated graphene oxide (m‐GO) to prepare hybrid nanoparticles (HNTs‐d‐GO). The microstructure and morphology analysis of HNTs‐d‐GO hybrid nanoparticles showed that the ordered lamellar structure of GO after acyl chlorination was stripped, and the organic groups on the surface of the lamellar increased. HNTs‐d‐GO hybrid nanoparticles were formed through the amidation of m‐HNTs and m‐GO. Then HNTs‐d‐GO hybrid nanoparticles were incorporated in galic acid epoxy resin to improve the thermal and mechanical properties. HNTs‐d‐GO/galic acid epoxy resin (HNTs‐d‐GO/GAER) bio‐based nanocomposites were prepared with methyl tetrahydrophthalic anhydride as curing agent. The galic acid epoxy composites with the addition of HNTs‐d‐GO exhibited significant enhancements of impact strength, tensile strength, storage modulus, and glass transition temperature. The initial thermal decomposition temperature (T5%) decreased, and the mass retention at 800°C increased, thermal stability of HNTs‐d‐GO/GAER composites were enhanced. At an optimum concentration of 0.75 wt% HNTs‐d‐GO, a simultaneous increase in strength and toughness was observed in comparison to the unfilled cured resin, the impact strength is 2.87 kJ/m2, which is 30.4% higher than pure GAER, and the tensile strength is 42.62 MPa, which is 29.2% higher than pure GAER. Compared with pure gallic acid epoxy resin, the content of HNTs‐d‐GO is 0.25 wt%, Tg increased by 28.9°C. [ABSTRACT FROM AUTHOR]