Risk of mechanical damage to PVC objects due to plasticiser loss

Abstract Loss of plasticisers over long-term exhibition or storage of poly(vinyl chloride) objects is expected to increase the stiffness and shrinkage, leading to deformation and potentially stress buildup in the material. This paper investigates the risk of fracture and irreversible deformation due to the diffusion–evaporation of plasticiser in three representative typologies: thin films/layers, whose free movement is restricted by rigid construction (e.g., resembling handbag coatings), bulk objects where surface layer is restraint in movement by the interior as a result of a plasticiser content gradient (e.g., mannequins), and inflatable objects where material stiffening under gravitational loads is considered (e.g., chairs). The analysis of the time-dependent mechanical response indicated that the rate of plasticiser loss is insufficient to cause crack/craquelure formation in all considered cases. On the contrary, permanent deformation due to plasticiser diffusion–evaporation is expected after ~100 years in thin PVC films, which are at the highest risk.