Russo Simona, Acocella Maria Rosaria, Mariconda Annaluisa, Volpe Valentina, Pantani Roberto, Longo Pasquale
Department of Chemistry and Biology, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, Italy.
Department of Science, University of Basilicata, Viale dell'Ateneo Lucano 10, 85100 Potenza, Italy.
Polymers (Basel). 2023 Jun 21;15(13):2770. doi: 10.3390/polym15132770.
An effective non-covalent compatibilization method for graphite and low-density polyethylene is reported. To obtain this result, pyren-1-yl-stearate (P1S) was synthesized, characterized and mixed with graphite to provide a better dispersion in polyethylene matrix. The P1S improves the dispersion of carbon filler in polyethylene through non-covalent compatibilization: the pyrenyl group gives π-π stacking interactions with graphite and the stearyl chain provides van der Waals interaction with the polymer chain (specifically London dispersion forces). In this study, different P1S/graphite fillers were prepared with a ratio by weight of 90/10 and 50/50, respectively, by using manual and ball-milling mixing. Their stability, interaction and morphology were evaluated through TGA, RX, and SEM. Thermogravimetric analyses showed that ball-milling mixing is more effective than manual mixing in promoting π-π stacking interactions of molecules such as P1S ester containing an alkyl chain and aromatic rings. The role of ball milling is confirmed by X-ray diffraction measurements since it was possible to observe both exfoliation and intercalation phenomena when this technique was used to mix the P1S ester with graphite. SEM analyses of polyethylene containing 1% of the carbon fillers again highlighted the importance of ball milling to promote the interaction of the ester with graphite and, simultaneously, the importance of the alkyl chain in order to achieve polyethylene-graphite compatibilization.
报道了一种用于石墨和低密度聚乙烯的有效非共价增容方法。为获得这一结果，合成并表征了芘-1-基硬脂酸酯（P1S），并将其与石墨混合，以使其在聚乙烯基体中具有更好的分散性。P1S通过非共价增容改善了碳填料在聚乙烯中的分散性：芘基与石墨形成π-π堆积相互作用，硬脂链与聚合物链提供范德华相互作用（具体为伦敦色散力）。在本研究中，分别通过手动和球磨混合制备了重量比为90/10和50/50的不同P1S/石墨填料。通过热重分析（TGA）、X射线衍射（RX）和扫描电子显微镜（SEM）对它们的稳定性、相互作用和形态进行了评估。热重分析表明，在促进含烷基链和芳环的P1S酯等分子的π-π堆积相互作用方面，球磨混合比手动混合更有效。X射线衍射测量证实了球磨的作用，因为当使用该技术将P1S酯与石墨混合时，可以观察到剥离和插层现象。对含有1%碳填料的聚乙烯进行的SEM分析再次强调了球磨对促进酯与石墨相互作用的重要性，同时也强调了烷基链对实现聚乙烯-石墨增容的重要性。
