Synthesis And Characterization Of Polysulfide Sealant For Ship Use

As a kind of long histlory elastic sealing materials, Polysulfide sealant show many advantages like oil resistance、climate resistance and last long. At present in my country, Polysulfide there still exist some problems such as long setting time and low bond performance that cannot satisfied with the demand of construction. In this paper, A new high-quality Polysulfide sealant was invented by network-structure control technology, chemically modification and physical modification. At the same time, the kind and amount of Thiokol, the kind of stuffing and dosage of each component are analyzed to the properties of the sealant. The protcet system of polysulfide sealant was also analyzed. Belows are the results:(1) The effect on Polysulfide sealant of different kinds of molecular weights rubber, plasticizer, tackifier and mixed stuffing. By mixing Thiokol of different molecular weights, The results shows that when the proportion of liquid Thiokol reach:higher:media:lower to4:1:2, tensile strength get promotion of20%than just one kind of Thiokol. Combining stuff like silica, light calcium carbonate, talcum powder with black carbon.The elongation at break and tensile strength can reach420%and 3.4Mpa while5phr silica,30phr black carbon,5phr talcum powder,5phr light calcium carbonate involved in all45phr stuffing.(2) In order to make full use of advantages of Polysulfide, Three-Component Polysulfide sealant was designed. By mixing The A components and B components in different ratio, the mechanical property requirements and the demand of curing time can be achieved, respectively. C component Acts as an Multi functional components, it contributes to the adhesive properties of Polysulfide sealant material.(3) The tackifier improve the bond behavior In exchange for lower tensile strength. So it is better to take0--6phr.(4) The curing speed of sealant related with dioxide content, t Triethylenetetramine and DPG. When manganese dioxide is greater than15, the content of curing agent has already reached saturation. When added0.4Phr Triethylenetetramine and0.9Phr DPG, the materials cured quickly. Materials appear better tensile properties while adding8Phr Silane, when adding more than11Phr Silane, mechanical properties decrease, when the adding amount was14phr, It just taking100hours to complete its curing process.(5) According to a certain proportion, mixing three component and let it sulfide. After it solidified, the Performance of protection system was tested. The result shows that the polysulfide sealant appearance good Thermal stability below200℃. The materials behaved high resistance to sea water. Even after a long time immersion in sea water,it can still maintain good performance.