Abstract: A method for detecting urea-formaldehyde resin in melamine-formaldehyde materials is provided. The method includes the following steps: washing samples to be tested with hydrochloric acid solution, placing it at 110° C.±5° C. for hydrolysis for 60 min±5 min, passing through a polyethersulfone filter membrane to obtain the test solution, and detecting the test solution through high-performance liquid chromatography-mass spectrometry.

Abstract: Disclosed in the present invention is a continuous stirrer, which comprises a receiving chamber provided with a front material inlet, a back material inlet and multilayer outer stirring needle groups along axial direction and a stirring shaft installed in the receiving chamber in a sealing manner and provided with multiple inner stirring needle groups along axial direction. The outer stirring needle groups and the inner stirring needle groups are staggered along axial direction, wherein inner stirring needles constituting the inner stirring needle groups and outer stirring needles constituting the outer stirring needle groups are arc or curve.