Studies On Melt-blown Electret Air Filtration Material Based On The Hindered Amine Light Stabilizer

Due to the high filtering efficiency and low filter resistance,Polypropylene melt-blown electret air filtration materials has always been a hotspot in research of air filter.However,the stability of the electret materials is susceptible to environmental condition.After long-term storage,the filtratlion efficiency of the materials drops dramatically.This study added hindered amine light stabilizer to improve stability of the polypropylene melt-blown materials.First of all,we chose a kind of commonly used hindered amine light stabilizer as additive in the previous preliminary experiments.After the previous preliminary experiments,there was something wrong with the compatibility between Hindered amine light stabilizer and Polypropylene.In order to solve this problem,the hindered amine light stabilizer and polypropylene were blended and extruded by twin-screw extruder to get the mixed Polypropylene.Good samples were prepared by using the mixed Polypropylene and then the samples were being charged.According to the above method,nine kinds of polypropylene melt-blown electret materials were prepared,three different proportions(0%,0.5%and 1%,respectively)and three different surface densities(25 g/m2,50 g/m2,75 g/m2 respectively).For comparing the effect of hindered amine and commercial master batch additives,six kinds of polypropylene melt-blown electret materials with master batch additives were prepared,two different proportions(5%and 10%respectively)and three different surface densities(25 g/m2,50 g/m2,75 g/m2 respectively).And then those samples were tested respectively.Results show that the hindered amine light stabilizers and commercial master batch additives in a certain extent,improved stability and filtrability of the polypropylene melt-blown electret materials.Treated with the same charge,the surface charge of melt-blown materials Containing hindered amine light stabilizers and commercial master batch decreased lower than the ordinary melt-blown materials,and commercial master batch is better than hindered amine light stabilizers Treated with the same special conditions(high humidity,high temperature and freezing),the filtration efficiency of ordinary polypropylene melt-blown electret materials was reduced by 10.35%;the polypropylene melt-blown electret materials Containing hindered amine light stabilizers only decreased by 5.44%(additive proportion 0.5%)and 6.05%(additive proportion 1%);the filtration efficiency of polypropylene melt-blown electret materials Containing commercial master batch additives was reduced by 2.52%(additive proportion 5%)and 2.80%(additive proportion 10%).The effect of master batch additives used in commercial is better than the hindered amine light stabilizers used in this article.Due to the low higher percentage,the hindered amine light stabilizer did not change the structure of the fiber fineness,aperture and permeability of the polypropylene melt-blown electret materials.Due to the high percentage,the commercial master batch additives had some influence on the fiber fineness,aperture,permeability and other performance of the melt-blown electret materials.Density increased,the average aperture decreased,permeability declined and filtration resistance increased.