新冠肺炎疫情期间，口罩成为不可或缺的防控利器和战略物资，是保障人民群众健康的盾牌。本项目面向“可重复使用防护口罩关键技术及产业化”重大需求开展应急攻关，提出并验证了“口罩荷电再生重复使用技术”，得到中央领导同志的两次批示并充分肯定（中国工程院），得到工信部、新华网等宣传报道普及，助力缓解了我国 2-3 月口罩供需矛盾；制定《可重复使用民用口罩》《儿童口罩》《复用式日常防护型口罩》团体标准；研发了新型高荷电熔喷聚丙烯复合材料，建成年产万吨新材料生产线，2020 年 3 月-8 月期间产销超6000 吨（可制口罩 60 亿只）；研制出具有杀灭新冠病毒功能（第三方检测）有机无机纳米复合滤材，并应用于可重复使用的“日用增强型口罩”制造；创制多种新型纳米纤维膜新材料并实现产业化，符合 KN95 口罩要求，可多次消毒重复使用，2020 年 3 月-7 月期间生产纳米纤维膜 1200 万平米（可制成口罩 4 亿只）；本项目研发的可重复使用民用口罩产品在北京、浙江、山东等地区推广应用，用户反馈效果良好；相关研究成果被 CCTV-1、北京卫视、光明日报等报道。随着疫情防控常态化，戴口罩仍是重要的自我防护手段。本项目相关技术成果，为老百姓提供了更先进、更安全、更舒适的防护产品，为推动缓解应急时期口罩供需矛盾做出了贡献。在保证安全的情况下，让每一只口罩发挥最大效能，数倍甚至十倍以上的提高口罩有效使用时间，科学合理使用口罩，避免过度消耗，符合绿色发展要求，是贯彻落实生态文明思想的体现。

Masks have become one of the most indispensable pieces of personal protective equipment and are important strategic products during the coronavirus disease 2019 (COVID-19) pandemic. Due to the huge mask demand–supply gap all over the world, the development of user-friendly technologies and methods is urgently needed to effectively extend the service time of masks. We report a very simple approach for the decontamination of masks for multiple reuse during the COVID-19 pandemic. Used masks were soaked in hot water at a temperature greater than 56 ℃ for 30 min, based on a recommended method to kill COVID-19 virus by the National Health Commission of the People’s Republic of China. The masks were then dried using an ordinary household hair dryer to recharge the masks with electrostatic charge to recover their filtration function (the so-called ‘‘hot water decontamination + charge regeneration” method). Three kinds of typical masks (disposable medical masks, surgical masks, and KN95-grade masks) were treated and tested. The filtration efficiencies of the regenerated masks were almost maintained and met the requirements of the respective standards. These findings should have important implications for the reuse of polypropylene masks during the COVID-19 pandemic. Some industry associations have issued related standards to ensure the quality and life of masks for multiple reuses, including the standards for reusable civil masks (T/BJFX 0001–2020) and for reusable daily protective masks (T/CSTM 00387–2020) that have been released by industry associations. In addition, we fabricated meltblown polypropylene-based high-performance planar face masks and investigated six commonly used disinfection methods and mask-wearing period on reusability of these masks. The results show that after three cycle treatments using 70 ℃ hot water for 30 min, which is one of the most scalable, user-friendly methods for viral disinfection, the particle filtration efficiency (PFE) of the mask remained almost unchanged and that, after mask-wearing for 24 h and subsequent disinfection using the same treatment procedures, the PFE dropped only 7.4% and the microbial indicators were well below the standard of reusable civil masks. We also developed new types of masks based on the use of nanofibers, which could also be reused for over 10 times. These works contribute to alleviating the panic over mask shortage and the optimal design of reusable masks.