The presented study was conducted in order to evaluate the correlation between the structural properties of recycled PET-based blends for materials using the three-dimensional (3D) printing technique. The recycled rPET resin was melt-blended with amorphous polyesters, poly(ethylene terephthalate) glycol (PETG), and poly(cyclohexylenedimethylene terephthalate) glycol (PCTG). The obtained blends were intended for the material extrusion printing method (MEX), while some of the samples were prepared by an injection molding technique. The study aimed to examine the impact of waste materials on the quality of products obtained in the MEX process. The tested materials were rPET/PETG and rPET/PCTG blends, and an elastomeric impact modifier was used to improve the toughness of the prepared composition. During the study, the reactive extrusion method was used for blend compatibilization. The samples were tested to determine their mechanical and thermal properties. A static tensile test, a Charpy impact test, and a hardness test were performed. Thermal analysis was performed by using HDT, DMTA, and DSC tests. The research showed that even a large share of the rPET material had a positive effect on the obtained mechanical and thermal performance of the tested samples. In addition, the annealed samples had higher values of HDT temperature as well as hardness and E modulus. The annealing procedure revealed that for heat-treated samples, the heat resistance was improved; however, in some cases, the warpage was present.

中文翻译：

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在增材制造技术中使用回收的聚对苯二甲酸乙二醇酯 （rPET） 共混物来制备可持续、坚韧和耐热的部件


本研究旨在评估使用三维 （3D） 打印技术为材料提供的回收 PET 基混合物的结构特性之间的相关性。回收的 rPET 树脂与无定形聚酯、聚对苯二甲酸乙二醇酯 （PETG） 和聚环己二亚甲基对苯二甲酸酯 （PCTG） 熔融共混。获得的混合物用于材料挤出打印法 （MEX），而一些样品是通过注射成型技术制备的。该研究旨在检查废料对 MEX 工艺中获得的产品质量的影响。测试材料是 rPET/PETG 和 rPET/PCTG 混合物，并使用弹性抗冲改性剂来提高所制备组合物的韧性。在研究过程中，反应挤出方法用于共混相容。对样品进行了测试，以确定其机械和热性能。进行了静态拉伸试验、简支梁冲击试验和硬度试验。使用 HDT 、 DMTA 和 DSC 测试进行热分析。研究表明，即使 rPET 材料的大部分对测试样品的机械和热性能也有积极影响。此外，退火样品的 HDT 温度值以及硬度和 E 模量值较高。退火程序表明，对于热处理样品，耐热性得到改善;但是，在某些情况下，存在翘曲。