Mock-Ups in Plastic Conservation Research: Processing and Aging of 3D Celluloid Specimens Simulating Historical...

Area of Science:

• Heritage Science
• Materials Science
• Polymer Chemistry

Background:

• Investigating cultural heritage objects often requires sampling, which can be destructive.
• Developing non-destructive analysis methods is crucial for preserving historical artifacts.
• Celluloid is a significant historical material found in many museum collections.

Purpose of the Study:

• To create representative three-dimensional (3D) celluloid mock-ups for heritage science research.
• To establish a methodology combining historical production techniques with laboratory-scale facilities.
• To validate the mock-ups' suitability for studying degradation processes in aged celluloid artifacts.

Main Methods:

• Acquisition and compression molding of prefabricated celluloid sheets into 3D shapes.
• Visual inspection to optimize molding conditions.
• Attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) to assess molecular integrity.
• Artificial aging protocols to simulate natural degradation.
• Ion chromatography (IC) and gel permeation chromatography (GPC) to analyze aging extent and degradation pathways.

Main Results:

• Successful fabrication of 3D celluloid mock-ups with representative geometries.
• ATR-FTIR confirmed no molecular heterogeneity introduced by the compression molding process.
• Artificial aging induced camphor loss, denitration, and main chain polymer scission, with scission being the dominant degradation mechanism.
• Comparison with historical objects indicated mock-ups represent moderately aged artifacts.

Conclusions:

• The developed method allows for the creation of realistic 3D celluloid mock-ups suitable for heritage science.
• These mock-ups serve as valuable tools for in-depth conservation research on moderately aged celluloid objects.
• This approach minimizes the need for sampling original cultural heritage materials.