Plastic Makes Perfect: Exploring a Modern Material

A selection of the plastic objects donated by Colin Williamson, plastics technologist and expert, to establish a Plastics Reference collection at the GCI. Photo by Anna Laganà

Plastic is everywhere. Look around and count how many objects contain some type of plastic—water bottles, food containers, or the device you’re reading this on right now. Plastic is an often unloved, but ubiquitous part of modern life—slow to degrade, confusing to recycle, overloading our landfills—but extremely versatile and convenient.

So…what is plastic, anyway? And why is the Getty Conservation Institute so interested in preserving it? Let’s take a look at the history of plastic, the many works of art and cultural heritage that are made using plastic, and the inventive research being done to better understand and protect it.

A Brief History of Plastic

The word plastic is from the Greek plastikos meaning “capable of being shaped or molded.” A signature of all plastics is the ability to mold them, which is one reason they are used to produce everything from medical devices to toys.

Plastic is a synthesized material made from organic polymers—long chains of repeating units of carbon and other atoms. Not all plastics are alike, and the difference frequently lies in how the elements are arranged in the polymer chains. Plastic is often modified with other substances, like plasticizers that can make it softer, less brittle, more flexible, more impact resistant, and easier to shape.

So, many of the plastics we normally interact with are organic polymers plus plasticizers.

The invention of plastics was gradual, and there is debate around who made the first plastic substance. Charles Goodyear is credited with vulcanizing natural rubber around 1847. An Englishman named Alexander Parkes created cellulose nitrate plastic in 1862. But the first synthetic polymer is usually attributed to Belgian chemist Leo Baekeland in the early 1900s and was called, appropriately, Bakelite. (You can still find many vintage and modern Bakelite products for sale online). From there, plastic-making took off, with scientists concocting recipes for everything from electrical and mechanical parts to mass-produced consumer goods like jewelry and hair combs.

Degraded cellulose acetate and cellulose nitrate objects used by the GCI team as study objects Photo by Anna Laganà

In the late-19th century, plastic went Hollywood and found a place in the exciting new world of movies and film. Cellulose nitrate was the first plastic film for early movie film and animation cels, but was also extremely flammable and had to be handled very carefully, as this early cautionary film attests.

Cellulose nitrate was later replaced by its close cousin, cellulose acetate, which was the go-to plastic for the mid-century nuclear family. Baby dolls and action figures for the kids, buttons on mom’s dress, and the rims of dad’s glasses were all often manufactured with cellulose acetate.

It seemed plastic could be used for just about anything, from beach balls to bullet-proof vests, and could last a lifetime (like the Tupperware handed down from your parents and grandparents).

Plastic Isn’t Forever

As durable as plastic may seem, some types of plastic are degrading dramatically, appearing stable for decades and then shrinking, distorting, and even disintegrating into piles of crumbs. Many historically significant plastic objects—early LEGO sets, animation cels, the spacesuits used by the first astronauts to land on the moon, and even the first container that held a McDonald’s Big Mac—are now threatened.

The Getty Conservation Institute has been working for a number of years with the Disney Animation Research Library to address the degradation of the library’s oldest and most treasured animation cels.

An animation cel of Snow White singing to the seven dwarfs that is exhibiting signs of cellulose plastic deterioration. © Disney Enterprises, Inc.

Similar threats also face works of art made from plastic, which became a popular medium for midcentury Los Angeles artists. Among these were “Finish Fetish” artists like Dewain Valentine, Fred Eversley, and Judy Chicago, who worked over days and months to smooth and shine their plastic creations to perfection. Their art was often inspired by the California landscape of shiny cars and even shinier surfboards—all emblems of a plastic-centric modern world. Today, many of these works of art are losing their shine as the plastic begins to show its age.

Senior Scientist at the Getty Conservation Institute, Odile Madden, understands these challenges. “In the 170 years that plastics have been around, people have seen that most kinds have problems as they age. These can be mechanical damages like scratches, dings, and breaks that come from using an object, and more insidious chemical degradation of the plastic itself. With any newly invented material, shortcomings are going to reveal themselves over time, and plastic is no exception. As plastic artworks and other objects make their way into museum collections, we find them breaking down in surprising and strange ways. There is an urgent need to develop new approaches to understand and conserve them.”

Making Plastic in the Lab

Inside the Getty Conservation Institute labs, a team of conservation scientists and conservators has been immersed in the study of plastic. Among them is scientist Michael Doutre, who has spent hours in the lab creating plastic discs, bars, and “dog bones,” stan­dard shapes used to test the strength and flexibility of all sorts of materials.

Injection-molded plastic ‘dog bones’ as seen in polarized light

The Getty Conservation Institute is creating its own plastic in order to figure out how to preserve it. Under­stand how cellulose acetate ages, and you are one step closer to conserving valued artworks and coveted collectibles. In a miniaturized plas­tic plant of sorts, Madden and Doutre produce shapes using several formulations of cellulose acetate that were frequently used in the 20^th century, but have since fallen out of favor.

“There has been a huge learning curve for us on how to make this plastic. A bit too much time has passed and the indus­trial know-how is just not there anymore, so it has been very interesting recreat­ing, effectively, lost methods based on descriptions and papers from decades ago,” said Doutre.

The Getty Conservation Institute science lab’s compounder-extruder. Photo by Andrzej Liguz.

One culprit in plastic’s degradation is the loss of plasticizers, which are, as mentioned above, substances that are often added to plastic to change the way it behaves. Some plasticizers have begun leeching out of the plastic, making them distort, discolor, become brittle, and more. But what, if anything, can be done to prevent or slow that process? And what other processes may be at work here?

Madden and Doutre are collecting data on cellulose acetate to find the optimal conditions for preserving the plastic objects that hold cultural value. They do this with a series of machines. The first mixes different kinds of plasticizers commonly used in the 20^th century. It squirts out a long plastic strand that resembles toothpaste coming out of a tube, which is cut into little pieces called nurdles. Each nurdle can be molded into shapes that can be manipulated—pulled, smashed, twisted—all in the name of research.

A strand of cellulose acetate plastic is fed into the pelletizer, which chops it into identical pieces. Photo by Andrzej Liguz.

More Fantastic Plastic Research

In addition to the plastic-making operation, the Conservation Institute is also developing treatment strategies for damaged plastic art objects, with the help of plastics conservator Anna Laganà. Laganà and her team are experimenting with treatments on mock-ups and the growing GCI reference collection of historical plastics to identify optimal techniques to treat chips, cracks and other damages, and finally applying them to real-life objects from museum collections.

Anna Laganà testing on the mock-ups materials and methods to repair damaged unsaturated polyester objects. Photo by Anna Flavin

“Repairing plastics is a challenging task for conservators, especially if the damaged plastic is transparent—there is nowhere for damage to run and hide,” said Lagana. “The difficulty is to find conservation materials able to recover transparency and strength without being harmful to the plastic. Therefore we have been working extensively to provide conservators with more options to successfully and safely repair transparent plastics, developing a variety of treatment techniques able to recover the lost transparency that are relatively simple to apply.”

Plastics were once the materials of the future, and are now treated as important artifacts of the past. For Doutre, this work has changed how he looks at these objects. “It has given me an appreciation for how much craft there is in the making of plastic objects. They are often viewed quite dismissively or as disposable, when just as much work, thought, and skill may have been put into them as a craft object made from traditional materials like ceramic, leather, or wood.”

Lab associate Michael Doutre and former graduate intern Debora Gobbo make cellulose acetate. Gobbo is gently pulling a plastic strand from the compounder-extruder. Photo Andrzej Liguz.

For more information, visit the Getty Conservation Institute’s Preservation of Plastics initiative.