Plasticizer migration from cross‐linked flexible PVC: Effects on tribology and hardness

Abstract

Uses of flexible poly(vinyl chloride) (PVC) are restricted by plasticizer migration affecting material properties. Moreover, the use of phthalate-based plasticizers is being questioned worldwide because of their potential toxicity to humans and environment. Chemical modification of PVC structure is one of the most effective tools for reduction of plasticizer diffusion. In this work, a flexible dry blend based on cross-linked PVC was obtained using a difunctional amine, namely isophoron diamine (IPDA) as the cross-linking agent. The gel fraction was evaluated from insoluble portions obtained by means of solvent extraction; the efficiency of cross-linking in reducing the plasticizer leaching was evaluated by migration tests. Effects of addition of IPDA on PVC thermal stability were determined by thermogravimetric analysis (TGA). The cross-linking reaction turned out to be responsible for accelerating thermal degradation. Tribological properties of flexible uncross-linked, cross-linked and rigid PVC were determined. Flexible formulations were held in contact for 32 days with rigid PVC sheets. Plasticizer migration towards the interface caused an increase of dynamic friction compared to that of the reference rigid PVC.Vickers microhardness h Vickers values of rigid PVC sheets decreased due to plasticizer surface absorption

Effect of Palm Oil Bio-Based Plasticizer on the Morphological, Thermal and Mechanical Properties of Poly(Vinyl Chloride)

“…Step 3 The results showed that all the plasticized PVC blends underwent three stages of degradation, and this was in agreement with earlier observations reported in the literature [2,21,23,34,35]. In the first stage of degradation, the weight loss was due to plasticizer evaporation.…”

The Influence of Polystyrene Modifier and Plasticizer Nature on the Properties of Poly(vinyl chloride)

“…The release of plasticizer is a negative factor affecting the final properties of polymer materials [10]. We studied kinetic regularities of plasticizer release depending on its nature and nature of polymer-modifier (Fig.…”

The effects of thermally reversible agents on PVC stability properties

“…It is well known that PVC thermal decomposition is from active chlorine structure began to emerge the HCl autocatalytic continuous degradation process, so try to remove or replace the active chlorine can effectively improve the strength of the PVC and heat resistance. The cross-linking of PVC is an effective method to enhance it [9][10][11][12][13][14][15][16]. Moreover, through the thermally reversible cross-linking method for modification of PVC, maybe improve the mechanical properties, environmental stress cracking resistance and reduce the permanent deformation products, moreover, the thermal stability performance of PVC may be enhanced through the introduction of sulfhydryl groups [17][18][19].…”