▎ 摘　　要

NOVELTY - Low-density poly sulfide sealant comprises base paste and vulcanizing agent in a mass ratio of 100:8-12. The base paste comprises 100 pts. wt. mercapto-terminated liquid poly sulfide rubber, 1-50 pts. wt. filler, 1-4 pts. wt. adhesion promoter and 5-50 pts. wt. hydrogen-containing silicone oil. The vulcanization agent comprises 100 pts. wt. manganese dioxide, 50-100 pts. wt. plasticizer, 1-10 pts. wt. accelerant, 1-10 pts. wt. vulcanizing inhibitor and 0.1-1 pts. wt. catalyst. USE - The low-density poly sulfide sealant is used for sealing in transportation, bridge building and aircraft whole oil tank, preferably aircrafts, automobiles, trucks, trains, boats, ships, submarines, and submarines. ADVANTAGE - The low density polysulfide sealant has good heat resistance, controllable density, which can effectively satisfy the aviation sealing agent to light and heat resistance. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a preparation method of the low density poly sulfide sealant, comprising weighing the mercapto liquid poly sulfide rubber, filling, placing in the stirrer to stir and vacuumizing and mixing, stirring for 30-60 minutes at the rotating speed of 500-800 revolutions/minute, adding hydrogen-containing silicone oil and adhesion promoter, vacuumizing and stirring for 30-60 minutes at the rotating speed of 500-800 revolutions/minute to obtain the base paste component, weighing manganese dioxide plasticizer, accelerator, vulcanizing inhibitor, and catalyst, grinding for 4-6 times on the three roller grinder or stirring for 30-60 minutes at the rotating speed of 500-800 revolutions/minute in the stirrer to obtain the vulcanizing agent component.