Study On Fabrication Of CTA Honeycomb Microporous Film By Breath Figures Method

Porous materials in many industries have a wide range of applications with more polymers can be successfully prepared a uniform pore structure.In this paper,Porous films with cellular structure have been prepared by breath figure method using cellulose triacetate(CTA)as film material and dichloromethane(DCM)as solvent.The influences of solvent,concentration,temperature,relative humidity on the morphology of porous films were investigated.Experimental results indicate that the honeycomb microporous film with pore size around 3μm can be prepared on glass slice with concentration of 0.5wt%-2.0wt%,temperature of 15℃-35℃,relative humidity of 70-90RH%.Pore size decreases with concentration and temperature increasing.Larger pore size can be prepared in a high humidity environment.Static method reduces the disturbance of air,which is beneficial to improve the regularity of the film.A large area honeycomb porous film was prepared by soaking the nonwoven fabric in the casting solution,changing the concentration and the manner of placement to examine the pore size and order degree.The purification of small particles in the air must be taken seriously as PM2.5 in the air has a certain threat to the health of the human body.The pore size of CTA/non-woven porous film in the range of 1μm to 4μm,and the air diameter of PM2.5 in this range,PM2.5 can be intercepted by CTA/non-woven porous film.The effects of films with different pore sizes,air flow rate and PM2.5 content on air entrapment efficiency were investigated.The results show that the CTA/non-woven porous film has an interception effect on PM2.5 in air.