Dunn Carmen B, Gunter Zoe, Griffin Anthony, Smith Paul, Al-Ostaz Ahmed, Ucak-Astarlioglu Mine G, Qiang Zhe
School of Polymer Science and Engineering, University of Southern Mississippi, 118 College Drive, Hattiesburg, Mississippi 39406, United States.
Department of Civil Engineering, University of Mississippi, Mississippi 38677, United States.
ACS Appl Eng Mater. 2025 May 15;3(6):1736-1744. doi: 10.1021/acsaenm.5c00210. eCollection 2025 Jun 27.
The use of polyolefins as carbon precursors has gained significant attention due to their low cost, wide availability, and potential for upcycling waste materials. A critical step in this process is using sulfuric acid as the chemical agent for sulfonation-enabled crosslinking of polyolefins, which forms thermally stable networks to allow their effective conversion into carbon upon pyrolysis. However, the hydrophobic nature of most commodity semicrystalline polyolefins often limits acid diffusion, making the reaction sluggish. This work investigates the impact of improving polyolefin hydrophilicity to enhance its sulfonation kinetics. By grafting hydroxyl groups onto the polyolefin backbone, we achieved significant enhancement in reaction efficiency. Specifically, just 2 h of crosslinking enables hydroxyl-functionalized, hydrogenated polybutadiene (hPB) to achieve over 50 wt% carbon yield after carbonization, whereas hPB requires 16 h of crosslinking to reach a comparable yield. These results highlight the significance of polyolefin carbon precursor design in overcoming diffusion limits, accelerating sulfonation kinetics, and improving carbon conversion efficiency, further advancing their use for carbon material production.
由于聚烯烃成本低、来源广泛且具有将废料升级再造的潜力，将其用作碳前驱体已受到广泛关注。该过程中的关键步骤是使用硫酸作为化学试剂，使聚烯烃发生磺化交联反应，从而形成热稳定网络，以便在热解时有效地将其转化为碳。然而，大多数商品半结晶聚烯烃的疏水性往往会限制酸的扩散，导致反应缓慢。本研究探讨了提高聚烯烃亲水性对增强其磺化动力学的影响。通过在聚烯烃主链上接枝羟基，我们显著提高了反应效率。具体而言，仅交联2小时，羟基官能化的氢化聚丁二烯（hPB）在碳化后就能实现超过50 wt%的碳产率，而未改性的hPB则需要16小时的交联才能达到类似产率。这些结果凸显了聚烯烃碳前驱体设计在克服扩散限制、加速磺化动力学以及提高碳转化效率方面的重要性，进一步推动了它们在碳材料生产中的应用。
