Phenolic Foam Toughed With Glutaraldehyde

Phenolic foam is one kind of heat insulating material due to its high resist heat temperature, good inflaming retarding property, fewer smog and innocuous. However, because methylene of phenolic resin can't guarantee internal rotaion ,and crosslinking density is high,so the problem influencing of the phenolic foam is the brittleness and. In this paper ,in order to solve the brittleness, The condition that benzene rings were only connected by methylene was changed by applying Glutaraldehyde in the structure of phenolic resin, and thus a better toughed phenolic foam was attained.In this paper, the reaction environment between glutaraldehyde and phenol was studied. The effects of reaction temperature and catalysts' use level on the rate of fasculation were investigated respectively. Moreover, the best experimental procedure parameters for the reaction between glutaraldehyde and phenol, such as reaction temperature and catalysts use level, are conformed by studying the influence of the use level of glutaraldehyde on vicosity, solid content, reaction activity and fasculation rate of PE resins. Result showed that the reaction activity of glutaraldehyde is lower than that of formaldehyde, and solidification reaction of the modified resin reduced as well. Furthermore, the gelating time became longer. The number average molecular weight and Molecular weight increased due to the concentration increase of glutaraldehyde.The effects of viscosity and solid content of resin on properties of foam were investigated, indexes of resin of operation available and getting good properties of foam were given: viscosity and solid content of resin should be controlled at 3000—4000cP and 75%—85%.When viscosity and solid content of resin were determined, the effects of foaming temperature, blowing agent and acid catalyst on properties of foam were discussed, such conclusions were draw: higher foaming temperature was beneficial to getting good foam, but too higher foaming temperature led to perforation. The more acid catalyst content, rise time and tack free time of foam were shorter, performance density,compressive strength and percent moisture content were higher ,but it should be controlled at 10%—15%,in order to get good quality of phenolic foam.The content of blowing agent is above 16%,the experimental result indicate that quality of phenolic foam and compressive strength are small. Foaming reaction was taken by using glutaraldehyde. Compression intensity, flexural strength, water ratio, water-absorbing capacity, weight loss and LOA were investigated by related tests. Result showed that the addition of glutaraldehyde could improve the compression and flexure mechanical property of loam. It also improved the ductility of loam, and markedly reduced the bloom level and the flame-retarded performance the loam. Moreover, the loam with 15% glutaraldehyde possessed the best overall performance.