Abstract:

In order to study effect of process on structure characteristics and filtration performance, the samples of gradient filters consist with PPS fibers and PTFE microfibers were made. The relationships between the process (gran weight of microfiber layers and the hydroentangling energy) and structure characteristics were discussed, and the quadratic models also have been established. The results show that the gram weight of PTFE microfiber layers has a significant influence on structure and filtration performance of the samples, the samples has model pores size is 20.22μm and the filtration efficiency is 63.41% for 2.05μm when the PTFE microfiber layers gram weight is 49±3.8g/m2. As the PTFE microfiber layers gram weight increases to 181±12.5g/m2, the model pores size reduced to 12.52μm, and filtering efficiency of the 2.05μm particle increases to 91.87%. In addition, the results also found that, the filtration efficiency and filtration resistance increased with the hydroentangling energy in the range of 3738kJ/Kg~8755kJ/Kg. Furthermore, Quadratic models have high degree of confidence intervals, which means that the models is good for the process design of the high temperature resistant fibrous filters with a graded structure.

Key words: nonwoven filter, high temperature resistant fiber, gradient structure, process disign, quadratic models