Customers often ask us why polyurethane casters suffer from aging and become prone to cracking after long-term storage. In fact, this is not a defect of the casters themselves, but a normal occurrence.

I. Causes of Aging in Polyurethane Casters

There are various factors contributing to the aging of polyurethane casters. Generally speaking, the primary triggers include environmental influences such as oxidation, ultraviolet radiation, humidity, high temperatures, low temperatures and chemical solvents, as well as inherent properties of the polymer, including its molecular chain structure and chemical stability.

II. Impacts of Polyurethane Caster Aging

Aging alters the physical and chemical properties of polyurethane casters, manifested as darkening discoloration, surface cracking, reduced hardness and diminished elasticity. As aging progresses, the casters gradually lose their functional performance, ultimately resulting in material failure. In practical applications such as construction sealants, artificial leather products and automotive seats, aged polyurethane casters may pose potential safety hazards.

III. Does Aging Soften Polyurethane Materials?

Aging reduces the hardness and elasticity of polyurethane casters, which may soften the material, yet softening is not the only sign of aging. For instance, deteriorated compression resistance will cause permanent deformation when the caster bears loads. Naturally, physical indicators including hardness and elasticity shift significantly before and after aging, serving as key metrics to assess the degree of material aging.