Migration of plasticizers

Definition

Migration of plasticizers refers to the process where additives, specifically plasticizers, move out of a polymer matrix and into the surrounding environment. This phenomenon can lead to material instability, affecting the physical properties of the materials and contributing to inherent vice, which is the tendency of certain materials to deteriorate over time due to their chemical composition.

5 Must Know Facts For Your Next Test

1. Plasticizers are commonly used in materials like PVC to enhance flexibility; however, their migration can lead to brittleness over time.
2. The migration process can occur due to temperature fluctuations, humidity, and physical stress on the material.
3. As plasticizers migrate out of the polymer matrix, it can create voids and decrease the overall mechanical strength of the material.
4. This phenomenon can result in changes in color, surface texture, and other aesthetic qualities of artworks or artifacts made with such materials.
5. Long-term exposure to migrated plasticizers can lead to contamination issues as these substances may leach into adjacent materials or environments.

Review Questions

• How does the migration of plasticizers impact the physical properties of polymers used in conservation?
  • The migration of plasticizers significantly alters the physical properties of polymers by reducing their flexibility and increasing brittleness. As plasticizers leave the polymer matrix, it weakens the material, making it more susceptible to cracking or breaking. This deterioration can compromise the integrity of artworks and artifacts, necessitating careful monitoring and potential restoration efforts.
• Discuss the relationship between migration of plasticizers and inherent vice in materials used for conservation.
  • The migration of plasticizers is a key aspect of inherent vice since it represents a fundamental flaw within the material itself. When plasticizers migrate, they contribute to the degradation of the polymer structure, leading to irreversible changes in both aesthetic and functional properties. Understanding this relationship is crucial for conservators as it helps them identify vulnerabilities in materials and develop strategies for preservation.
• Evaluate the long-term implications of plasticizer migration on conservation practices and material selection.
  • The long-term implications of plasticizer migration are profound for conservation practices as they necessitate a reevaluation of material selection. Conservators must consider not only the immediate benefits of using flexible materials but also their potential for future instability due to plasticizer loss. This awareness influences decisions about which materials are suitable for specific applications, ultimately guiding the development of more durable alternatives that mitigate the risks associated with inherent vice.

Related terms

Plasticizers: Additives used in polymers to increase flexibility, workability, or extensibility by reducing intermolecular forces.

Inherent Vice: A defect or characteristic in materials that leads to deterioration or damage over time, often independent of external conditions.

Polymer Degradation: The process through which polymers break down or lose their properties due to environmental factors, including heat, light, and chemical exposure.