In this study, the high-energy ball-milled nanodiamonds (MNDs) are carefully treated with low-temperature annealing and mixed acids to obtain carboxylated MNDs (cMNDs). This process not only removes impurities but also grafts oxygen containing functional groups onto MNDs surfaces. Then poly (vinyl alcohol) (PVA)/cMND nanocomposites are prepared by a facile aqueous solution casting method. Compared with PVA/MND, an improved dispersion of nanoparticles in the matrix and higher nanoparticles content can be achieved by PVA/cMND. It is found that glass transition temperature (T_g) and loss factor peak temperature (T_tanδ) of PVA/cMND nanocomposites are both shifted to higher values than pure PVA. Thermal decomposition of PVA is obviously suppressed by cMNDs. The onset and maximum decomposition temperatures increases by over 17 °C and 24 °C, respectively. The thermal conductivity increases by 57.5%. Furthermore, tensile strength and Young’s modulus of PVA are improved by 62.3% and 166.7% with the addition of cMNDs.

在这项研究中，高能球磨纳米金刚石（MNDs）经过低温退火和混合酸的仔细处理，以获得羧化MNDs（cMNDs）。该过程不仅去除杂质，而且将含氧官能团接枝到MND表面。然后通过简便的水溶液流延法制备聚乙烯醇（PVA）/ cMND纳米复合材料。与PVA / MND相比，PVA / cMND可以提高纳米粒子在基质中的分散性，并提高纳米粒子的含量。据发现，玻璃化转变温度（Ť_克）和损耗因子峰值温度（Ť _tanδ的）PVA / cMND纳米复合材料都比纯PVA具有更高的值。cMNDs明显抑制了PVA的热分解。起始和最高分解温度分别升高了17°C和24°C以上。导热系数增加了57.5％。此外，通过添加cMND，PVA的抗张强度和杨氏模量分别提高了62.3％和166.7％。