▎ 摘　　要

NOVELTY - Aqueous polyurethane emulsion comprises 60-70 pts. wt. polyurethane prepolymer, 2-4 pts. wt. crosslinking agent, 0.1-5 pts. wt. active auxiliary agent, and 14-34 pts. wt. water. The crosslinking agent is maleic acid derivatives, polyethylene polyamine compounds or hydroxy-containing acrylate compounds. The active auxiliary agent includes reactive group among double bond, hydroxy group, amino group, carboxy group and epoxy group. USE - Used as an aqueous polyurethane emulsion. ADVANTAGE - The aqueous polyurethane emulsion: has good stability; improves the wave-absorbing performance of the aqueous polyurethane wave-absorbing coating; and is green and environmentally friendly. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for : (1) preparing an aqueous polyurethane emulsion comprising mixing polyurethane pre-polymer and crosslinking agent for crosslinking reaction, adding the active auxiliary agent and water to continuously react, and adjusting the pH of the system to 8-10; (2) aqueous polyurethane wave-absorbing coating 0.1-1.2 pts. wt. wave material, 0.3-0.7 pts. wt. dispersant, 0.3-0.7 pts. wt. pH regulator, 0.1-0.7 pts. wt. defoamer, 5-10 pts. wt. curing agent, 20-40 pts. wt. water; (3) preparing polyurethane wave-absorbing coating comprising mixing water, dispersant, defoamer and wave absorbing material, stirring and dispersing, adding the pH adjuster to adjust the pH of the system to 8-10, adding the basic emulsion and the remaining water, and stirring to disperse, adding the curing agent, stirring and dispersing, and grinding the resulting mixture; and (4) wave-absorbing honeycomb comprising a honeycomb core material and the aqueous waterborne polyurethane wave-absorbing coating attached to the honeycomb core material.