Abstract:This paper studied the relationship between five kinds of natural latex sponges with different latex contents (80NR, 60NR, 50NR, 40NR, 0NR) and aging time, and explored the aging degree and aging characteristics of latex sponges by using yellowness index, whiteness index, crosslinking density, compression density and infrared spectrum. The results showed that the yellowness index and whiteness index of sponges with more latex content increased and decreased faster, and the yellowness index tended to converge at last. The crosslinking density is closely related to the indentation hardness. At the early stage of reaction, the indentation hardness decreases as the crosslinking density increases, while at the later stage, both the crosslinking density and indentation density continue to increase. In the whole process of aging, the latex sponge has oxidation reaction, the carbon-carbon double bond disappears, and the formation of esters, ethers and peroxide, but the methyl group does not disappear because of the reaction.