Recycled plastics: additives and their effects on properties
The degradation undergone by plastics products during their processing and subsequent lifetime worsens all the characteristics of the polymers, and recycling operations therefore give rise to secondary materials with poor properties. This holds for all recycled polymers, both homogeneous and heterogeneous, but in the latter case other difficulties arise from recycling . The incompatibility between the different polymer phases, indeed, leads to materials having properties even lower than those of the pure components. Therefore, to obtain recycled polymers with acceptable properties it is necessary to protect the material from degradation phenomena and/or to try to enhance the crucial properties. Finally, for mixed plastics, the use of compatibilizing agents (see entry on ‘Compatibilizers for recycled polyethylene’) can be very useful. This means that for re-stabilization, the addition of fillers, modifier agents and compatibilizers is, in many cases, a necessary operation to carry out during recycling. The use of similar additives, or at least some of them, is of course usual also with virgin polymers, but it can be particularly important for recycled materials.
Keywordspolymer recycling stabilizer compatibilizer filler
Unable to display preview. Download preview PDF.
- 1.La Mantia, F.P. (1996) Basic Concepts on the Recycling of Homogeneous and Heterogeneous Plastics, Recycling of PVC and Mixed Plastics (ed. F.P. La Mantia), ChemTec, Toronto.Google Scholar
- 2.Dietz, S. (1992) Phosphite Stabilizers in Postconsumer Recycling, in Emerging Technologies in Plastics Recycling (eds Andrews, G.D. and Subramanian, P.M.) ACS Symposium Series 513, Washington, 134.Google Scholar
- 3.Herbst, H., Hoffmann, K., Pfaendner, R., Sitek, F. (1995) Stabilizers Allow Production of Higher Added-Value Post-Use Plastics, Polymer Recycling, 1, 157.Google Scholar
- 4.Marrone, M., La Mantia, F.P. Re-Stabilization of Recycled Polypropylenes, in press, Polymer Recycling.Google Scholar
- 5.Vinci, M., La Mantia, F.P., Properties of Filled Recycled Polypropylene, in press J. Polym. Eng. Google Scholar