Preparation And Properties Of PAN Pre-oxidized Fiber Composite High Temperature Resistant Filter Materials

Preoxidized fiber is the middle product of preparing the carbon fiber,it is made up of PAN fibers during the 200-300? in air oxidation,due to the rate problem of the high performance carbon fibers,there are a lot of preoxidized fibers were abandoned,they were usually used as heat preservation material.The limit oxygen index of preoxidized fiber is more than 45%,it has the ability of not melt,softening,no shrinkage.In the atmospheric environment of 300?,it's characteristics still stable.Besides,the price of preoxidized fiber is more cheaper than other high temperature resistant fibers,makes it be the ideal material of filter material.But as it exist the problem of poor mechanical properties and cohesive force,we chose the PPS fiber and Aramid 1313 mixed with preoxidized fiber,adopted needle punching and calender finishing process to make an excellent high temperature resistant performance,the advantages of low cost,high filtration efficiency filter material.By combining image analysis technology and orthogonal experiment to investigate the best parameters of preoxidized felt,we found that the preoxidized fiber after carding,it's strength becomes very poor,so we mixed certain proportion other fibers to improve web uniformity and strength.This topic has prepared four categories mixed high temperature resistance filter material,it includes preoxidized fiber/PPS fiber high temperature resistant filter material,preoxidized fiber/PPS fiber reinforced high temperature resistance filter material,preoxidized fiber/aramid 1313 fiber high temperature resistant filter material,preoxidized fiber/aramid 1313 fiber reinforced high temperature resistant filter material,the results showed that:1,with the increasing of the mixed fiber,the MD breaking fracture strength,CD fracture strength and breaking elongation were obviously improved.With the increase of fiber content,the strength was increased.2,With the increase of mixed fiber,the permeability and pore size decreased,the pore size distribution was more concentrated.The filtration efficiency of 5?m reached 100%.The filter material can apply to reality.3,Various performance indexes of fiber increased by adding the base fabric to the filter material,the results showed that by adding PTFE fabric,the MD strength is 4 times than the same proportion filter material,by adding glass fabric,the MD strength is 6 times than the same proportion filter material.The reinforced high temperature resistant filter material has better average pore size and air permeability,it also showed that the filtration efficiency and filtration resistance has improved.It's comprehensive performance more suitable for the actual working condition.4,The heat resistance performance of mixed PPS filter material is suitable for 200?,which mixed with aramid 1313 suitable for higher than 210?.