▎ 摘　　要

NOVELTY - A polyurethane flame-retardant wave-absorbing material is obtained by polymerizing 100 parts mass polyether polyol, 20-70 parts mass toluene diisocyanate, 0.01-0.5 part mass nano-carbon sol, 10-20 parts mass deionized water, 5-30 parts mass dimethyl methylphosphonate, 2-8 parts mass graphene oxide, 10-30 parts mass iron oxide, 1-10 parts mass zinc borate, 0.02-0.4 part mass stannous octoate, 0.03-0.6 part mass triethylenediamine, 0.2-3 parts mass silicone surfactant and 1-10 parts mass sodium bicarbonate. The polyether polyol has a hydroxyl value of 30-60 mg potassium hydroxide/g. USE - Polyurethane flame-retardant wave-absorbing material. ADVANTAGE - The polyurethane flame-retardant wave-absorbing material has low smoke, low toxicity, excellent flame retardance and excellent wave absorption property. DETAILED DESCRIPTION - A polyurethane flame-retardant wave-absorbing material is obtained by polymerizing 100 parts mass polyether polyol, 20-70 parts mass toluene diisocyanate, 0.01-0.5 part mass nano-carbon sol, 10-20 parts mass deionized water, 5-30 parts mass dimethyl methylphosphonate, 2-8 parts mass graphene oxide, 10-30 parts mass iron oxide, 1-10 parts mass zinc borate, 0.02-0.4 part mass stannous octoate, 0.03-0.6 part mass triethylenediamine, 0.2-3 parts mass silicone surfactant and 1-10 parts mass sodium bicarbonate. The polyether polyol has a hydroxyl value of 30-60 mg potassium hydroxide/g. The toluene diisocyanate has isocyanate index of 0.60-1.15. An INDEPENDENT CLAIM is included for method for preparing flame-retardant polyurethane wave-absorbing material, which involves mixing polyether polyol, dimethyl methylphosphonate, nano-carbon sol, iron oxide, zinc borate, stannous octoate, triethylenediamine, deionized water and silicone surfactants, stirring evenly at room temperature, subjecting the obtained mixture into ultrasonic dispersion treatment, then adding toluene diisocyanate, and ultrasonically stirring for 5-10 minutes, adding graphene oxide and sodium bicarbonate, quickly pouring into a mold for foaming at room temperature for 30-90 minutes to obtain wave-absorbing material gel, and freeze-drying wave-absorbing material gel.