Study On Preparation And Properties Of Basalt Fiber Wet-laid Nonwoven Thin Felt

Basalt fiber is not only environmentally friendly,but also has the advantages of high strength,high modulus,high and low temperature resistance,corrosion resistance,etc.It has become a research hotspot at home and abroad.However,there are relatively few studies on basalt fiber wet-laid nonwoven thin felt at present.In this paper,basalt fiber was used as raw material,the dispersibility of basalt fiber in suspension was studied in order to make basalt fiber with poor dispersibility disperse evenly in suspension,then the process of producing basalt fiber wet-laid nonwoven thin felt was discussed and studied,and the reasonable process and parameters were determined.Finally,the basalt fiber wet-laid nonwoven thin felt with good performances was produced by wet-laid nonwoven process.The wet-laid nonwoven thin felt made of basalt fibers was tested and following were the conclusions obtained:(1)Using basalt fiber as raw material,the basalt fiber nonwoven thin felt with good properties can be prepared by wet-laid nonwoven process.The reasonable process was modification of fiber ? fiber shearing ? preparation of suspension ? beating ? forming? bonding ? drying ? roll.(2)Using hydrochloric acid to modify basalt fiber can effectively improve the dispersibility of basalt fiber in suspension.The Box-behnken response surface method was used to design the experimental scheme of modification of basalt fiber with hydrochloric acid,and obtained a regression model which was well fitted to the actual situation and can predict the dispersion of basalt fiber well.The order of factors affecting the dispersion of basalt fiber was modification time > modification temperature > hydrochloric acid concentration.And the optimum process parameters of modified basalt fiber were hydrochloric acid concentration 2.1 mol/L,modification time 14 h,and modification temperature 53.4 ?.(3)In the process of hydrochloric acid modification,zeta potential test and scanning electron microscope test were performed on the basalt fiber before and after modification.It was found that the Zeta potential of basalt fiber after modification was significantly reduced,the surface of basalt fibers was smooth,and there was no obvious concave and convex marks,this indicated that acid treatment changed the zeta potential of basalt fiber,thus improving the dispersion performance of basalt fibers.(4)When the modified basalt fibers were dispersed,adding a certain amount of dispersant additives in the suspension of the modified basalt fibers was beneficial to further improve the dispersibility of the fibers.Orthogonal test shows that the order of factors affecting the dispersion of basalt fibers in suspension was concentration of dispersant >acidity and alkalinity of suspension > concentration of thickener.The optimum suspension ratio was concentration of polyethylene oxide dispersant 1.5%,concentration of hydroxyethyl cellulose thickener 0.5%,and p H value of basalt fibers suspension 5.(5)When the modified basalt fiber suspension was beaten,the dispersing effect of adding dispersing agent first and then beating was better than that of first beating and then adding dispersing agent,but too many beating times would cause the original dispersed fibers to tangle together again and reduce the dispersion of basalt fiber.The optimum beating parameters were beating time of 5 s and beating rate of 8000 rpm.(6)The epoxy resin was used as the binder,and the resol was used as the curing agent to bond and strengthen the basalt fiber wet-laid thin felt.The order of factors affecting the breaking strength of basalt fiber wet-laid felt was as follows: binder concentration > curing time > curing temperature.The best adhesion and reinforcement process was adhesive concentration 20%,curing time 70 min,curing temperature 150 ?.(7)The basalt fiber wet-laid nonwoven thin felt prepared in this paper has good properties and can be used as the base material of waterproof roll material,etal,it has a wide range of uses.