目的 探索塑料包装的碳足迹评价技术，建立健全该行业碳足迹改进的技术方法。方法 运用生命周期评价法，对塑料罐包装的碳足迹建模、数据采集和计算结果进行分析，并讨论关联因素的影响;基于碳足迹评价结果，提出评价对象生命周期碳足迹的改进方案。结果 研究发现系统边界内单件20 L塑料罐包装的碳足迹为2.48 kg-CO2-eq;再生料改性、吹塑成型的碳足迹贡献度达17.5%，75.8%;新料使用的单项碳足迹达1.02 kg-CO2-eq，再生料质量分数增加5%，碳足迹下降了7.67%;单位容积碳足迹随着包装容积增大而减小。结论 由于原生资源消耗量的减少，再生塑料资源的利用，可以明显改善包装生产的物料和电力碳足迹;同配比下大体积规格的包装设计对于提高单件包装的利用效率起到积极作用;跨境再生料的使用、合理包装设计、绿色电力应用等均是改善塑料罐包装碳足迹的有效方案。

The work aims to explore the carbon footprint evaluation technology of plastic packaging, establish and improve the carbon footprint improvement technology of the industry. Based on the life cycle assessment method, the carbon footprint modeling, data collection and calculation results of plastic packaging were analyzed. The influence of related factors was discussed, and an improvement scheme of evaluation object based on life cycle carbon footprint was proposed. The results showed that, within the system boundary, the carbon footprint of each 20 L plastic can be up to 2.48 kg-CO2-eq; and the contribution of modification of recycled materials and blow molding reached 17.5% and 75.8%, respectively. The carbon footprint of the new materials in this package was 1.02 kg-CO2-eq. When the mass fraction of recycled materials increased by 5%, the carbon footprint decreased by 7.67%. The carbon footprint per unit volume decreased as the package volume increased. It is found that, the utilization of recycled plastics can improve the carbon footprint of package materials and power because of the decrease of primary resource consumption. Under the same proportion, the packaging design of large volume specification plays a positive role in improving the utilization efficiency of single package. The use of cross-border recycled materials, reasonable packaging design and green power applications are all effective solutions to improve the carbon footprint of plastic can packaging.