In this study, 3D printed polylactic acid (PLA) objects were recycled into lactide monomers using various commercially available catalysts, including triazabicyclodecene (TBD), tin (II) ethylhexanoate; Sn(Oct)2 and titanium (IV) isopropoxide; Ti(OiPr)4. The PLA objects were first dissolved in dichloromethane and then processed into catalyst embedded films or electrospun fibers. The degradation of PLA was performed under both static air and nitrogen flow conditions, demonstrating that electrospun fibers with 0.5 % mol catalyst loadings exhibited superior degradation performance compared to films. For instance, the electrospun fibers with Sn(Oct)2 catalyst achieved a turnover frequency (TOF) of 3400 h−1. Thermogravimetric analysis (TGA) and degradation constant (kobs) calculations confirmed that the fibers had a significantly higher degradation rate due to their increased surface area and better catalyst distribution. The isolation of l-lactic acid (L-LA) from the degradation products was achieved with an average yield of 95 %, indicating the effectiveness of the recycling process. This research highlights the potential for efficient PLA recycling using catalyst-embedded electrospun fibers, offering a sustainable approach to polymer waste management.

中文翻译：

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使用薄膜或超细纤维形式的 Sn、Ti 和三氮杂双环癸烯基催化剂回收聚（l-乳酸）基 3D 打印物体


在这项研究中，使用各种市售催化剂将 3D 打印的聚乳酸 （PLA） 物体回收成丙交酯单体，包括三氮杂双环癸烯 （TBD）、锡 （II） 乙基己酸酯;Sn（Oct）2 和钛 （IV） 异丙醇;Ti（OiPr）4.PLA 对象首先溶解在二氯甲烷中，然后加工成催化剂包埋薄膜或静电纺丝纤维。PLA 的降解是在静态空气和氮气流动条件下进行的，表明与薄膜相比，催化剂负载量为 0.5 % 的静电纺丝纤维表现出优异的降解性能。例如，使用 Sn（Oct）2 催化剂的静电纺丝纤维实现了 3400 h-1 的周转频率 （TOF）。热重分析 （TGA） 和降解常数 （kobs） 计算证实，由于纤维的表面积增加和催化剂分布更好，因此降解速率明显更高。从降解产物中分离出 l-乳酸 （L-LA） 的平均产量为 95%，表明回收过程的有效性。这项研究强调了使用催化剂嵌入的静电纺丝纤维高效回收 PLA 的潜力，为聚合物废物管理提供了一种可持续的方法。