Arcos Camila, Muñoz Lisa, Cordova Deborah, Muñoz Hugo, Walter Mariana, Azócar Manuel I, Leiva Ángel, Sancy Mamié, Rodríguez-Grau Gonzalo
Departamento de Ingeniería Mecánica y Metalúrgica, Facultad de Ingeniería, Pontificia Universidad Católica de Chile, Santiago 7820436, Chile.
Instituto de Química, Facultad de Ciencias, Pontificia Universidad Católica de Valparaíso, Valparaíso 2373223, Chile.
Polymers (Basel). 2022 Nov 30;14(23):5220. doi: 10.3390/polym14235220.
In this study, the effect of the recycling process and copper particle incorporation on virgin and recycled pellet HDPE were investigated by thermo-chemical analysis, mechanical characterization, and antibacterial analysis. Copper particles were added to pellet HDPE, virgin and recycled, using a tabletop single screw extruder. Some copper particles, called copper nano-particles (Cu-NPs), had a spherical morphology and an average particle size near 20 nm. The others had a cubic morphology and an average particle size close to 300 nm, labeled copper nano-cubes (Cu-NCs). The thermo-chemical analysis revealed that the degree of crystallization was not influenced by the recycling process: 55.38 % for virgin HDPE and 56.01% for recycled HDPE. The degree of crystallization decreased with the addition of the copper particles. Possibly due to a modification in the structure, packaging organization, and crystalline ordering, the recycled HDPE reached a degree of crystallization close to 44.78% with 0.5 wt.% copper nano-particles and close to 36.57% for the recycled HDPE modified with 0.7 wt.% Cu-NCs. Tensile tests revealed a slight reduction in the tensile strength related to the recycling process, being close to 26 MPa for the virgin HDPE and 15.99 MPa for the recycled HDPE, which was improved by adding copper particles, which were near 25.39 MPa for 0.7 wt.% copper nano-cubes. Antibacterial analysis showed a reduction in the viability of in virgin HDPE samples, which was close to 8% for HDPE containing copper nano-particles and lower than 2% for HDPE having copper nano-cubes. In contrast, the recycled HDPE revealed viability close to 95% for HDPE with copper nano-particles and nearly 50% for HDPE with copper nano-cubes. The viability of for HDPE was lower than containing copper nano-particles and copper nano-cubes, which increased dramatically close to 80% for recycled HDPE with copper nano-particles 80% and 75% with copper nano-cubes.
在本研究中，通过热化学分析、力学表征和抗菌分析，研究了回收过程和铜颗粒掺入对原始和回收颗粒状高密度聚乙烯（HDPE）的影响。使用台式单螺杆挤出机将铜颗粒添加到原始和回收的颗粒状HDPE中。一些铜颗粒，称为铜纳米颗粒（Cu-NPs），具有球形形态，平均粒径接近20nm。其他的具有立方形态，平均粒径接近300nm，标记为铜纳米立方体（Cu-NCs）。热化学分析表明，结晶度不受回收过程的影响：原始HDPE为55.38%，回收HDPE为56.01%。随着铜颗粒的添加，结晶度降低。可能由于结构、堆积组织和结晶有序性的改变，回收HDPE在添加0.5wt.%铜纳米颗粒时结晶度接近44.78%，在添加0.7wt.%Cu-NCs改性的回收HDPE中结晶度接近36.57%。拉伸试验表明，与回收过程相关的拉伸强度略有降低，原始HDPE接近26MPa，回收HDPE接近15.99MPa，添加铜颗粒后有所改善，添加0.7wt.%铜纳米立方体时接近25.39MPa。抗菌分析表明，原始HDPE样品中的活力降低，含铜纳米颗粒的HDPE接近8%，含铜纳米立方体的HDPE低于2%。相比之下，回收HDPE显示含铜纳米颗粒的HDPE活力接近95%，含铜纳米立方体的HDPE接近50%。HDPE中 的活力低于含铜纳米颗粒和铜纳米立方体的情况，对于含铜纳米颗粒的回收HDPE，活力急剧增加至接近80%，含铜纳米立方体的为75%。
