Miedzianowska Justyna, Masłowski Marcin, Strzelec Krzysztof
Institute of Polymer & Dye Technology, Lodz University of Technology, Stefanowskiego 12/16, 90-924 Lodz, Poland.
Materials (Basel). 2020 Apr 1;13(7):1598. doi: 10.3390/ma13071598.
Thermoplastic elastomer blends based on natural rubber (NR) and ethylene-vinyl acetate copolymer (EVA) with different weight ratios (30, 40, 50, 60 and 70 parts per hundred rubber (phr) of NR) and 10, 20 and 30 phr of straw were prepared and characterized. Current environmental problems were the motivation to produce this type of system, namely: the need to replace plastics at least partly with natural materials; increasing the amount of renewable raw materials and managing excess straw production. When using this bioadditive in traditional materials, the high processing temperature can be problematic, leading to the degradation of straw fibers. The solution can be polymer mixtures that are prepared at significantly lower temperatures. Scanning electron microscope (SEM) imaging was used to investigate the particle size of fibers and phase morphology of composites. Moreover, determination of the thermal properties of the filler and composites showed that the processing temperature used in the production of NR/EVA blends reduces the risk of degradation of the natural filler. Differential scanning calorimetry (DSC) was used to determine the thermal behavior of the filled composites. Finally, rheological tests of materials allow the determination of optimal processing parameters and properties of materials in dynamic conditions. The proposed blends exhibit elastic properties, and due to the lack of chemical cross-linking they can be processed and recycled like thermoplastics. In addition, they offset the disadvantages and combine the advantages of natural rubber and ethylene-vinyl acetate copolymer in the form of thermoplastic elastomeric biocomposites.
制备并表征了基于天然橡胶（NR）和乙烯-醋酸乙烯酯共聚物（EVA）的热塑性弹性体共混物，其中NR的重量比不同（每百份橡胶（phr）中含30、40、50、60和70份NR），秸秆含量为10、20和30 phr。当前的环境问题促使人们生产这种类型的体系，具体如下：需要至少部分地用天然材料替代塑料；增加可再生原材料的用量以及处理过量的秸秆产量。在传统材料中使用这种生物添加剂时，较高的加工温度可能会产生问题，导致秸秆纤维降解。解决办法可以是在显著较低温度下制备的聚合物混合物。使用扫描电子显微镜（SEM）成像来研究纤维的粒径和复合材料的相形态。此外，对填料和复合材料热性能的测定表明，NR/EVA共混物生产中使用的加工温度降低了天然填料降解的风险。使用差示扫描量热法（DSC）来测定填充复合材料的热行为。最后，材料的流变学测试能够确定动态条件下材料的最佳加工参数和性能。所提出的共混物具有弹性性能，并且由于缺乏化学交联，它们可以像热塑性塑料一样进行加工和回收。此外，它们以热塑性弹性体生物复合材料的形式弥补了天然橡胶和乙烯-醋酸乙烯酯共聚物的缺点并结合了它们的优点。
