Sealant is a kind of sealing material that can fill the joint and the bonding interface indefinitely, and withstand the displacement and deformation of the joint. It is usually a paste-like material that connects the substrates into a whole after curing. Early sealants were made of dry (or non-dry) viscous materials, such as Zhejiang green, tar, natural (or synthetic) resin, and natural (or synthetic) rubber. There are currently three types of high-performance sealants: polysulfide sealants, silicone sealants and polyurethane sealants. The flame-retardant sealant based on modified polyether polymer and its preparation method are a new type of modified sealant. The main chain of this type of polymer is polyether with hydrolyzable silane end groups, so it has a silicone seal. Advantages of glue and polyurethane sealant. The formula of silicon-modified polyether sealant is composed of silicon-modified polyether resin as the main component, curing catalyst, reinforcing filler and various modified additives. Modified additives, such as plasticizers, coupling agents, accelerators, pigments, stabilizers, thixotropic agents, etc. However, the above components are flammable, have low combustion oxygen index and low ignition point, and will release toxic gases during combustion.

　　To this end, technicians provide a flame-retardant sealant based on modified polyether polymer, which is solvent-free, good flexibility, good adhesion to inorganic materials such as glass, aluminum, marble, good UV resistance, and good stability , After a fire, it has the advantage of self-extinguishing; its preparation method: a flame-retardant sealant based on modified polyether polymer, made of the following mass parts of raw materials: modified polyether 10 35, flame retardant 5 15. Plasticizer 12 50, inorganic filler 15 40, catalyst 0.01 0, antioxidant 0.14 0. Modified polyether is a silane-modified ternary polyoxypropylene ether with an average molecular weight of 4500 6000 or 6000 8000. The flame retardant is octabromodiphenyl ether, triphenyl phosphate, decabromodiphenyl ethane, decabromodiphenyl ether or zinc borate. The plasticizer is dibutyl phthalate; the inorganic filler is acetylene carbon black; the catalyst is stannous octoate; the antioxidant is 2.6-di-tert-butyl-p-cresol. The preparation method of flame retardant sealant based on modified polyether polymer includes the following steps: 1. Weigh all the raw materials according to the formula; 2. Add the modified polyether into the reactor and slowly heat it to 180-200°, Degas in vacuum for 1-2 hours, and cool to 60-80°; 3. Add plasticizers, inorganic fillers, antioxidants, catalysts and flame retardants, and stir in vacuum for 12 hours at 80°C; 4. Cool To 30-40°, fill with nitrogen to eliminate the vacuum. The vacuum degree of vacuum degassing and vacuum stirring is maintained at 0.1MI^a±0.02Mpa, and the nitrogen pressure in the step is not limited, mainly to release the vacuum.

　　The beneficial effects of the above flame-retardant sealant are: solvent-free, good flexibility, good adhesion to inorganic materials such as glass, aluminum, marble, UV resistance, combustion oxygen index higher than 21%, and the preparation method is simple and easy to implement.