Can We Make Plastic from Shrimp Shells?

Shrilk could be the next material to replace plastic once and for all. It is a degradable bioplastic derived from shrimp shells and silk protein.

The ill effects of synthetic single-use plastic on the environment are well-known. A study by the US National Park Service indicates that plastic bottles can take up to 450 years to disintegrate and decompose. Researchers for the longest time were looking for biodegradable options that can meet the requirements.

One of the most promising discoveries for a potential alternative is Shrilk - a classic example of bio-mimicking, where designers draw ideas from how various living organisms function. Examples include the design of the Japanese bullet train, which was inspired by a bird's beak. In this case, the inspiration for the material was derived from the functioning of insect cuticles. 

The process in the manufacture of Shrilk, which consists of layering two common polymers, was developed by Javier Fernandez and Donald Ingber, both belonging to Harvard's Wyss Institute for Biologically Inspired Engineering. 

In the case of Shrilk, it consists of Fibroin, which is a silk protein obtained from the domestic silkworm Bombyx mori. This is combined with Chitosan, which is derived from shrimp shells. Since the ingredients required for this are by-products of other processes and are available abundantly at low cost, the potential of this material as a possible replacement for plastics is immense. 

Javier also explains "how the process of layering Shrilk is not chemical, except the interface of layers." The material's strength is comparable to that of aluminium alloy, that too, at half the weight. Shrilk is also hydrophilic, letting its properties be altered with how much water is added. 

On top of being completely biodegradable, chitosan in Shrilk is also a good nitrogenous fertilizer and fungicide. The properties of it being anti-fungal and bacterial make it an ideal choice for storing food items for longer periods. 

The possibility of Shrilk being put to wide use is soon to be expected as its ingredients have already cleared the US Food and Drug Administrations tests. 

A wide range of case scenarios for its usage is being probed by researchers. Shrilk can be used in the biomedical field, especially for surgical structures, gauze, and temporary scaffolds for tissue implants. These are intended to provide initial support and later harmlessly dissolve into the body fluids. 

Shrilk also offers the potential to be molded into different shapes, making it ideal for complex structures. In short, we have at hand a material that has all the characteristics of its counterparts and is devoid of the various harmful effects that plague the environment.