Abstract In this work, polypropylene (PP) filled with different proportions of CoSt were prepared in a twin-screw extruder by compounding technique. Eight films of these compounds were prepared using compression moulding. The modified PP films were characterized for chemical, physical, thermal, and morphological properties (before and after biodegradation). The biodegradation of the CoSt filled PP films was studied under controlled composting conditions, and the degradation intermediates were evaluated for their ecotoxicological impact. The CoSt present in the PP film was confirmed by Fourier transform infrared spectroscopy. As the addition of CoSt was progressively increased, the tensile strength and thermal stability decreased as shown by UTM and thermogravimetric analysis. The compounding of CoSt in PP reduced its crystallinity as revealed by the differential scanning calorimetry and X-ray diffraction analysis, and this led to enhanced degradation of PP. After biodegradation, SEM results of modified PP films showed rougher morphology than before biodegradation. The maximum biodegradation (19.78%) was shown by the film having 2 phr CoSt. The ecotoxicity tests of the degraded material, namely, microbial test, plant growth test, and earthworm acute-toxicity test demonstrated that the biodegradation intermediates were nontoxic. Hence, CoSt filled PP has high industrial potential to make biodegradable flexible packaging.

中文翻译：

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助氧化剂浓度对硬脂酸钴填充聚丙烯包装膜特性的影响

摘要 本研究在双螺杆挤出机中采用复合技术制备了不同比例CoSt填充的聚丙烯(PP)。使用压塑法制备了八种这些化合物的薄膜。改性聚丙烯薄膜的化学、物理、热和形态特性（生物降解之前和之后）进行了表征。在受控堆肥条件下研究了 CoSt 填充 PP 薄膜的生物降解，并评估了降解中间体的生态毒理学影响。PP薄膜中存在的CoSt通过傅里叶变换红外光谱证实。如 UTM 和热重分析所示，随着 CoSt 添加量的逐渐增加，拉伸强度和热稳定性降低。差示扫描量热法和 X 射线衍射分析表明，CoSt 在 PP 中的复合降低了其结晶度，这导致了 PP 的降解增强。生物降解后，改性聚丙烯薄膜的 SEM 结果显示出比生物降解前更粗糙的形态。具有 2 phr CoSt 的薄膜显示出最大的生物降解 (19.78%)。降解材料的生态毒性试验，即微生物试验、植物生长试验和蚯蚓急性毒性试验表明，生物降解中间体是无毒的。因此，CoSt 填充 PP 在制造可生物降解的软包装方面具有很高的工业潜力。改性PP薄膜的SEM结果显示出比生物降解前更粗糙的形态。具有 2 phr CoSt 的薄膜显示出最大的生物降解 (19.78%)。降解材料的生态毒性试验，即微生物试验、植物生长试验和蚯蚓急性毒性试验表明，生物降解中间体是无毒的。因此，CoSt 填充 PP 在制造可生物降解的软包装方面具有很高的工业潜力。改性PP薄膜的SEM结果显示出比生物降解前更粗糙的形态。具有 2 phr CoSt 的薄膜显示出最大的生物降解 (19.78%)。降解材料的生态毒性试验，即微生物试验、植物生长试验和蚯蚓急性毒性试验表明，生物降解中间体是无毒的。因此，CoSt 填充 PP 在制造可生物降解的软包装方面具有很高的工业潜力。