An innovative bioinspired method is presented for the preparation of surface-modified nanodiamonds (ND) particles by poly(dopamine) (PDA). The process was aimed at improving the thermal conductivity and maintaining the insulating capability of silicone rubber (SiR). ND was successfully and effectively modified by dopamine in different hours, which was confirmed by HR-TEM, TGA, FTIR, and XRD . The poly(dopamine) coating on ND particles improved its interfacial interaction with silicon rubber and promoted the uniform dispersion of fillers, resulting in the ND-18/SiR composite that acquired a higher thermal conductivity (0.295 W/(m·K)) at the loading of 6 wt%, 81 % higher than that of pure silicone rubber (0.163 W/(m·K)). In addition, the composite materials still displayed an excellent insulating property with a resistance of ≈10 11 Ω·cm, which was a big advantage for thermal management.
Separation efficiency of solid-phase extractant is greatly subjected to the spatial configurations of functional ligands attached to the matrix, which has not been studied efficiently till now. In order to further understand the relationship between spatial configurations of the attached functional ligand and the adsorption ability of the extractant, two novel molecules (single-armed ligand, SA and double-armed ligand, DA) with identical coordination unit (amide–thiourea) but different spatial configurations (single/double arms) were designed and synthesized. The corresponding extractants, ND-SA and ND-DA were obtained by modification of nanodiamond (ND) with SA and DA and both the extractants displayed good chemical and thermal stabilities. The batch adsorption experiments showed that ND-SA and ND-DA possess large adsorption capacities (∼200 mg g −1 ), very fast adsorption kinetics (reaching equilibrium within 2 min) and excellent selectivities (up to 82% and 72%, respectively) for uranium. The study of the possible mechanism indicated that ND-DA tends to utilize its tweezer-like double arms to “clamp” metal ions and the stronger chelate interaction could to some extent weaken the coordination selectivity of attached DA ligand. In contrast, single-armed adsorbent ND-SA unexpectedly exhibited better adsorption selectivity for uranium than ND-DA owing to its more flexible spatial configuration and moderate complexing ability.
危险品化学品经营许可证（带存储）