Surface chemical modification of carbon nanotubes can enhance the compatibility with polymers and improve flame retardancy performances. In this work, the double bond active sites were constructed on the surface of carbon nanotubes modified by the γ-methacryloyloxypropyl trimethoxysilane (KH570). Glycidyl methacrylate (GMA) was further grafted onto the surface of carbon nanotubes via free radical polymerization. Finally, the flame retardant melamine polyphosphate (MPP) was bonded to the surface of carbon nanotubes by the ring-opening reaction. This modification process was proved to be achieved by infrared spectroscopy and thermogravimetric test. The carbon nanotubes modified by flame retardant were added into the epoxy matrix and cured to prepare flame retardant and thermal conductive composites. The flame retardancy of composites were studied by cone calorimetry, UL94 vertical combustion test and limiting oxygen index. The thermal conductivity of composites was characterized by laser thermal conductivity instrument. The results showed that when the addition amount of flame retardant MPP-modified carbon nanotubes in composites was 10 wt%, the flame retardant level of UL94 reached to V2, the limiting oxygen index increased from 25.1 of pure epoxy resin to 28.3, the PHRR of pure epoxy resin was reduced from 800 kW/m2 to 645 kW/m2 of composites and thermal conductivity of composites was enhanced from 0.21 W/m·K−1 of pure epoxy resin to 0.42 W/m·K−1 of the composites.
The phenotypic plasticity hypothesis suggests that exotic plants may have greater phenotypic plasticity than native plants. However, whether phenotypic changes vary according to different environmental factors has not been well studied. We conducted a multi-species greenhouse experiment to study the responses of six different phenotypic traits, namely height, leaf number, specific leaf area, total biomass, root mass fraction, and leaf mass fraction, of native and invasive species to nutrients, water, and light. Each treatment was divided into two levels: high and low. In the nutrient addition experiment, only the leaf mass fraction and root mass fraction of the plants supported the phenotypic plasticity hypothesis. Then, none of the six traits supported the phenotypic plasticity hypothesis in the water or light treatment experiments. The results show that, for different environmental factors and phenotypes, the phenotypic plasticity hypothesis of plant invasion is inconsistent. When using the phenotypic plasticity hypothesis to explain plant invasion, variations in environmental factors and phenotypes should be considered.