不同条件对口罩用熔喷布过滤效率与气流阻力的影响

Effects of different conditions on filtration efficiency and airflow resistance of mask spray cloth

研究不同条件下,口罩用聚丙烯熔喷布过滤效率和气流阻力的变化情况,为熔喷布的生产、应用和口罩的使用提供参考依据。通过选用不同的测试流量、叠加层数和加载时间3种条件,对口罩用熔喷布的盐性颗粒物过滤效率和气流阻力进行实验,结果发现,随着测试流量的增加,口罩用熔喷布的盐性过滤效率呈线性下降趋势,气流阻力呈线性增长趋势;随着样品叠加层数的增加,过滤效率先增大后趋于稳定,气流阻力值呈线性增大趋势;随着加载时间的延长,过滤效率和气流阻力结果均随之增大,但过滤效率增大趋势由急变缓,气流阻力由缓变急。因此,在熔喷布生产时可通过增大过滤面积来降低气体通过流量,也可以在口罩制作时适当地选用多层熔喷布,两者均可提高产品的过滤效率。另外,口罩不宜长期使用,不然会造成呼吸不畅。

The change of filtration efficiency and airflow resistance of polypropylene melt-spray cloth used in masks under different conditions was studied,which provided reference for the production,application and use of masks.The filtration efficiency and airflow resistance of salt particles used in the mask were tested and analyzed by using different test flow rate,stack layer number and loading time.It is found that with the increase of the test flow rate,the salt filtration efficiency of the mask is decreasing linearly,and the airflow resistance is increasing linearly.With the increase of the number of layers,the filtration efficiency increases first and then tends to be stable,and the airflow resistance increases linearly.With the increase of loading time,the filtration efficiency and airflow resistance increase,but the increasing trend of filtration efficiency changes from rapid to slow,and airflow resistance from slow to rapid.Therefore,the airflow rate can be reduced by increasing the filter area in the production of melt spray cloth,and the multi-layer melt spray cloth can be selected appropriately in the manufacture of mask,both of which can improve the filtration efficiency of the product.In addition,the mask should not be used for a long time,otherwise it will cause dyspnea.