High-weather-fastness polysulfide sealant

The invention discloses high-weather-fastness polysulfide sealant, which comprises base cream and vulcanizing cream, wherein the base cream comprises the components by weight: 30-70% of liquid polysulfide rubber, 20-60% of padding, 1-10% of tackifier, 3-20% of plasticizer, 0.3-5% of coupling agent, 0.1-2% of antioxidant and 0.05-1% of anti-ultraviolet agent; the vulcanizing cream comprises the components by weight: 25-70% of vulcanizing agent, 25-70% of plasticizer and 0.5-5% of vulcanization accelerator; and the mixed weight ratio of the base cream to the vulcanizing cream is 100 to (6-14). The invention also discloses a preparation method of the polysulfide sealant. The invention also discloses a preparation of the high-weather-fastness polysulfide sealant. The polysulfide sealant is characterized in that the weather fastness of the sealant is improved by the antioxidant and the anti-ultraviolet agent; the material cost is low, the process is stable, and the reproducibility is good. The high-weather-fastness polysulfide sealant disclosed by the invention can be used for bonding sealing elements of buildings, ships, high-speed trains, automobiles and the like, therefore, the high-weather fastness polysulfide sealant has a great application value in industry.