Degradation Process of Static and Dynamic Mechanical Properties of Polyurea under Acid-Alkali-Salt Corrosion Condition

The mechanical properties and protective performance of polyurea under extreme conditions were investigated by immersing the polyurea material in a 5% (mass fraction) solutions of H₂SO₄, NaOH and NaCl. Mechanical performance tests were conducted using a GL-028 testing machine and a separated Hopkinson compression bar to obtain stress-strain curves at different strain rates. The changes in the mechanical properties of polyurea materials before and after immersion in different environments were analyzed. The results show that polyurea materials had excellent salt and alkali resistance, and were relatively sensitive to acidic environments. After soaking in acidic environments, their tensile strength and peak stress were reduced by 34.45% and 20.3%, respectively. With the prolongation of soaking time, the elastic modulus and stress of polyurea material showed an increasing trend, showing a certain time-dependent effect. The morphology observation results indicated that no significant damage was found in the polyurea, which demonstrated excellent corrosion resistance.