Plastics are in most museum collections that feature objects from the 1860s onwards. The material is everywhere – ubiquitous in fashion, design and social history collections, prolific in science, technology and medical, and often in decorative arts and ethnography. They are even in zoology and mineralogy, where they can be used to simulate natural materials.
Awareness of typical uses
Some plastics are recognisable by their look or feel, or the type or style of the object. Some have iconic status with irrefutable historical value – such as Bakelite 1930s radios or 1960s Mary Quant coats. Others are less obvious, as substitutes or imitations of other materials.
Plastics are easily missed in mixed material objects, especially if covered up or internal. Some uses are simply unexpected. Below are some possible uses.
1860s to 1940s:
- Cellulose nitrate, cellulose acetate and casein, common for simulating ivory, amber, horn, tortoiseshell and coral and often for objects that are held, worn or decorative.
- Phenolformaldehyde (Bakelite, dark colours) and thioureaformaldehyde (light colours) for hardwearing uses.
Awareness of typical uses
Some plastics are recognisable by their look or feel, or the type or style of the object. Some have iconic status with irrefutable historical value – such as Bakelite 1930s radios or 1960s Mary Quant coats. Others are less obvious, as substitutes or imitations of other materials.
Plastics are easily missed in mixed material objects, especially if covered up or internal. Some uses are simply unexpected. Below are some possible uses.
1860s to 1940s:
- Cellulose nitrate, cellulose acetate and casein, common for simulating ivory, amber, horn, tortoiseshell and coral and often for objects that are held, worn or decorative.
- Phenolformaldehyde (Bakelite, dark colours) and thioureaformaldehyde (light colours) for hardwearing uses.
Post-1940s:
- Nylon, polyester, polystyrene, polyvinylchloride (PVC), polyethylene and polyurethanes, in moulded, sheet, foam and film forms with many wide and varied applications.
- Polymethylmethacrylate (Perspex) and polycarbonate for protective and decorative glass-like uses.
- Acrylonitrile butadiene styrene (ABS), ureaformaldehyde, urethanes and other co-polymers as resins and for functional objects like furniture.
- Cellulose acetate remains popular for handles and spectacle frames.
Identification is difficult by look and feel alone, and needs scientific analysis involving infrared spectroscopy – although even this is not always conclusive. Workshops and training from experienced experts are very important.
Problem plastics
- Nylon, polyester, polystyrene, polyvinylchloride (PVC), polyethylene and polyurethanes, in moulded, sheet, foam and film forms with many wide and varied applications.
- Polymethylmethacrylate (Perspex) and polycarbonate for protective and decorative glass-like uses.
- Acrylonitrile butadiene styrene (ABS), ureaformaldehyde, urethanes and other co-polymers as resins and for functional objects like furniture.
- Cellulose acetate remains popular for handles and spectacle frames.
Identification is difficult by look and feel alone, and needs scientific analysis involving infrared spectroscopy – although even this is not always conclusive. Workshops and training from experienced experts are very important.
Problem plastics
Familiar plastic objects, especially those with recent history, are often overlooked. The consequences of this are incomplete object records and misunderstood significance.
Dissociation is perhaps the most widespread problem for plastics preservation. It is important to gather and retain material information at the point of acquisition and accessioning.
Plastics in museum collections need the same preventive care as other materials. This is often not realised until irreversible deterioration occurs, bringing loss and ethically challenging decisions about access, preservation and retention.
Plastics are not manufactured with long-term preservation in mind, which is why they degrade and do not last as long as expected. This change is unpredictable, making vigilance through surveys essential.
Tackling the issue
Dissociation is perhaps the most widespread problem for plastics preservation. It is important to gather and retain material information at the point of acquisition and accessioning.
Plastics in museum collections need the same preventive care as other materials. This is often not realised until irreversible deterioration occurs, bringing loss and ethically challenging decisions about access, preservation and retention.
Plastics are not manufactured with long-term preservation in mind, which is why they degrade and do not last as long as expected. This change is unpredictable, making vigilance through surveys essential.
Tackling the issue
While the scale and range of historical plastics is vast, and degradation unpredictable, positive actions such as collection surveys and object observation can help.
Take a close look at the most significant or valuable objects known or expected to be post-1860s. Are they obviously plastic or might they be?
Is the feel, weight, patterns, colours and/or shape of the object “plastic” or unnatural? Anything that looks like a natural material, including leather and those mentioned above, could be a plastic.
Does the collection record have any information? Search with words like artificial, synthetic and man-made. Even if the exact plastic isn’t given, the fact a plastic is recorded is a start.
Are there signs of material degradation? As well as those mentioned above, look for the following:
- Corrosion of metal parts and disintegrated paper or card, and/or acrid or “vinegar” smells, all caused by vapours from degrading cellulose nitrate and acetate (take care – these are harmful).
- Discolouration, especially yellowing and darkening, common for PVC.
- Sticky or liquid on surfaces from plasticiser loss, especially imitation leather.
- Delamination of a plastic joined to another material, especially sequins and films.
- Foam that has distorted or is crumbling.
Update and maintain documentation and object records with observations and images, and gather this information for new acquisitions and donations.
Preventive measures
Plastics need the same stable environmental conditions as other organic materials within similar ranges of temperature, humidity and UV-filtered light. They should be stored and handled with the same care too, even if the materials look robust, new or undegraded. Take photographic records to monitor changes.
Active degradation is problematic. “Venting” of vapours by unwrapping objects may stabilise them but can affect other materials around them. Containing vapours by enclosing the object may form an equilibrium or could hasten its disintegration. Removing surface liquids can also encourage more degradation. Remedial conservation is emerging but still in early stages of research.
Health and safety of staff and visitors is very important. Acidic vapours and plasticisers are hazardous to health. Always open boxes and bags carefully, and wash hands after handling.
If an object is beyond help or no longer suitable to keep or use, consider donating it to conservation and conservation science research.
Anita Quye is a senior lecturer in conservation science and the programme convenor for the Modern Material Artefacts MSc at the Centre for Textile Conservation and Technical Art History, University of Glasgow
Take a close look at the most significant or valuable objects known or expected to be post-1860s. Are they obviously plastic or might they be?
Is the feel, weight, patterns, colours and/or shape of the object “plastic” or unnatural? Anything that looks like a natural material, including leather and those mentioned above, could be a plastic.
Does the collection record have any information? Search with words like artificial, synthetic and man-made. Even if the exact plastic isn’t given, the fact a plastic is recorded is a start.
Are there signs of material degradation? As well as those mentioned above, look for the following:
- Corrosion of metal parts and disintegrated paper or card, and/or acrid or “vinegar” smells, all caused by vapours from degrading cellulose nitrate and acetate (take care – these are harmful).
- Discolouration, especially yellowing and darkening, common for PVC.
- Sticky or liquid on surfaces from plasticiser loss, especially imitation leather.
- Delamination of a plastic joined to another material, especially sequins and films.
- Foam that has distorted or is crumbling.
Update and maintain documentation and object records with observations and images, and gather this information for new acquisitions and donations.
Preventive measures
Plastics need the same stable environmental conditions as other organic materials within similar ranges of temperature, humidity and UV-filtered light. They should be stored and handled with the same care too, even if the materials look robust, new or undegraded. Take photographic records to monitor changes.
Active degradation is problematic. “Venting” of vapours by unwrapping objects may stabilise them but can affect other materials around them. Containing vapours by enclosing the object may form an equilibrium or could hasten its disintegration. Removing surface liquids can also encourage more degradation. Remedial conservation is emerging but still in early stages of research.
Health and safety of staff and visitors is very important. Acidic vapours and plasticisers are hazardous to health. Always open boxes and bags carefully, and wash hands after handling.
If an object is beyond help or no longer suitable to keep or use, consider donating it to conservation and conservation science research.
Anita Quye is a senior lecturer in conservation science and the programme convenor for the Modern Material Artefacts MSc at the Centre for Textile Conservation and Technical Art History, University of Glasgow
