The addition of structural sugars to cardboard reinforces its strength to rival plastic packaging

Since my early childhood, I have been very passionate about nature. While other kids played sports and video games, I spent my time hiking around outside, uncovering amphibians, insects, and arachnids at the parks near my house. Through shelves of field guides and frequent trips to the library, my parents helped me to fuel this passion for discovery.

As I grew older, I became more and more aware of the dire need to preserve and study these ecosystems. Entering my Freshman year, I began my studies in ecology and conservation by assessing the health of our campus lake through fishery statistics. At the end of the year, I presented this research to the Student Wildlife Symposium, a local science conference in Ohio. There, I had the amazing opportunity of interacting with and presenting to other students that were equally committed in their studies of the environment. After this experience, I knew that science research was something that I wanted to continue throughout the next three years of high school.

The summer after Freshman year, I began drafting my research plan for a new project. This was when I first came across the topic of bioplastics. When I began researching new developments in the world of biodegradable plastics, though, I was met with highly tedious processes that required technology and materials that I could not reasonably acquire. So instead, I asked the question, “Is there a way that we can manipulate materials that are already biodegradable in order to increase their usage and lessen the strain of single use plastics on our ecosystems?” Through reading an article on the development of bioplastics at the Georgia Institute of Technology, I came across the two highly abundant carbohydrates, Chitosan and Cellulose. Chitosan is derived from Chitin, which is an important component of the structure of the exoskeletons of arthropods. Cellulose is an important component of the cell walls of plants. Since they are both structural carbohydrates, I wondered if they could be used to reinforce the structure of some common manufactured materials.

As the next school year began, I hypothesized that through dehydration synthesis (the way in which these carbohydrates are formed), these polymers could bond to a hydrophilic substrate. Thinking of ubiquitous biodegradable, hydrophilic materials, I chose corrugated cardboard as my primary material of interest. By mixing these carbohydrates with water in spray bottles, I reasoned that I could spray the mixture onto the surfaces of these paper-based materials, causing the water to soak in, leaving layers of the carbohydrates.

I began my research, trying to test if these polymers could strengthen corrugated cardboard and common construction paper. After testing the strength of my layered materials using a force table, I realized that I did not have nearly enough data to make any claims. Therefore, my first science fair was spent with an incomplete project.

Feeling disappointed with how things turned out, I began preparations for the next year. Then Covid hit. Although I was at home for about a year and three months, I managed to persevere and push forward with my work.

During that summer after Sophomore year, I was determined to try again, and prepared forty sample sets of corrugated cardboard and paperboard. Each set of 10 samples had a different number of layers (control, 2, 4, and 6).

Although I had no access to a lab or any of my previous materials, I set up my own work station in the basement, next to the washing machine. This simple setup consisted of a folding table, a new supply of carbohydrates, and lab equipment. As one day bled into the next, the research that I performed down in my basement, became one of my few escapes.

The major challenge that I faced during that time was the construction of an apparatus

that could test the tensile strength of my prototypes. I began by attempting to use a sort of pulley system with clamps in between, that would utilize the weight of water to break the samples. This resulted in a minor flood of the area. It was at that time that we just began discussing the concept of simple machines in my physics class. Inspired by this, I built an apparatus that utilized force tension out of common materials that I found in my garage. After testing all my prototypes and running several statistical tests, I discovered that my project was a success. The addition of the carbohydrates had significantly strengthened the corrugated cardboard and paperboard samples.

For the first time since Freshman year, I was able to approach the (now virtual) science conferences with confidence. Through important feedback from practicing chemical engineers, I was introduced to new methods of layering to minimize water damage and found more ways to expand my research in its scope. Although they were virtual and far less personal, I cite these experiences as some of the most important in my life thus far.

Right now, I am in the middle of analyzing data that I’ve collected from a mass loss system that I created in order to test the effects of this coating on degradation of the cardboard within the approximate conditions of the Great Pacific Garbage Gyre. The hope is that through adding these carbohydrate polymers, which are mostly insoluble in water, I can also increase the water resistance of corrugated cardboard.

As of now, my plan in the years to come is to expand my knowledge of chemistry and physics, and eventually get my PhD in Biology with a concentration on ecology and conservation, thus achieving my lifelong dream of playing my part in protecting the ecosystems that I have grown so close to.

Strengthening Hydrophilic, Biodegradable Materials Using Chitosan and Cellulose

The goal of this project was to strengthen biodegradable, hydrophilic materials by adding chitosan and cellulose polymers as a substitute for single use plastic coating. The first expectation was that materials with chitosan and cellulose polymers will be stronger than their normal counterparts. The second expectation stated that materials with the greatest amounts of these polymers will be the strongest. Alternating layers of chitosan and cellulose dispersions (50ml water-100mg carbohydrate) were sprayed onto four sets of cardboard and paperboard samples (8 total). Each set of samples was assigned a different amount of layering (0, 2, 4, 6). An apparatus built from two clamps, a wooden frame, a threaded rod, paracord, digital fish scale, and a turnbuckle, was used to break the materials utilizing tension, and record the max amount of kg applied to them at their breaking points. An ANOVA was performed to discover if the treatment worked, as well as differences between each trial. A Tukey test was used to determine significant and nonsignificant differences in strength between layers. Due to the overall significance of p< .0001 (cardboard) and p= 0.04 (paperboard), the first expectation was met for both materials. The second expectation wasn’t met, as the mean strength of the six-layer paperboard samples decreased from the mean strength of the four-layer paperboard samples by 3.234 kg. With a P-value of less than 0.01 from the control samples to four-layer samples and six-layer samples, it seems as though the optimal layering for cardboard samples would be four layers.

This is a slow motion video of my testing apparatus. The number of kilograms applied to the materials at their breaking points were displayed by a digital fish scale and captured by a slow motion camera.