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In this paper, a silicon‐oxygen coupling agent (MPS) with a double bond is hydrolyzed with graphene oxide (GO) to obtain MPS‐GO. The polymerization of MPS‐GO with the phosphorus‐containing monomer (HEPO) is initiated with 2,2′‐Azobis(2‐methylpropionitrile) (AIBN) to obtain multi‐elements hybrid polymer brushes grafting graphene oxide (HM‐GO). As a flame retardant, different amounts of HM‐GO are added to obtain EP composites. In this system, the properties of composite flame retardant obviously increase with the increasing of HM‐GO. The limiting oxygen index (LOI) value of composites with 4 wt% addition of HM‐GO is 31.0%, while the LOI value of EP‐0 is only 23.9%. And the peak heat release rate (PHRR) value is reduced from 515.8 W g−1 of pure epoxy resin to 376.9 W g−1. In addition, with the increase of HM‐GO addition, the Tg value, flexural strength and flexural modulus of EP composites are improved. Through calculation, it is proved that the rising of Tg was due to the increase of crosslink density of the system. The flame retardant performance and mechanical properties of the composite materials are steadily improved, indicating that such flame retardants are dispersed well in the epoxy resin. HM‐GO is an efficient macromolecular modified graphene oxide halogen‐free flame retardant, which can improve both flame retardant properties and mechanical properties.

Multiple responsive polymers have attracted increasing attention for a wide range of applications including nanocarriers and nanocomposite catalysts. Herein, an amphiphilic block copolymer P­(NIPAAm-r-CA)-b-PMMA was synthesized by reversible addition–fragmentation chain-transfer polymerization with coumarin units embedded in the side chain. Followed by a reduction of the terminal group to hydrosulfonyl, relatively stable polymer microspheres can be prepared after self-assembling, and those microspheres could be further employed as carriers of gold nanoparticles (Au NPs) due to the strong interrelationship between −SH and Au. The polymer microspheres with Au NPs decorated onto the surface were endowed with reversible catalytic properties by adjusting temperature and UV irradiation owing to the introduction of photo-responsive coumarin units and thermo-responsive poly­(N-isopropyl acrylamide) segments. Moreover, the catalytic performance could be retained even after several cycles of photo- or thermo-responsive regulation. Importantly, the fluorescence of the smart polymer under different pH values was studied to clarify the mechanism of emission, laying a necessary foundation for further visualization of the catalytic process.