Microplastics are small pieces of plastic and are used in coatings that protect any product from decomposition against environmental conditions. Industrial products, insecticides or herbicides, vitamins or chemical compounds are stored in microcapsules, allowing them to be slowly released over a targeted period of time. However, a significant portion of microplastics, which are becoming increasingly widespread, are long-lasting pollutants that do not biodegrade and are detected in the air, water, soil and even in the bloodstream of animals and humans.

The European Union wants non-biodegradable microplastics to be eliminated by 2025. For this reason, the search for a cheap and easily obtainable raw material that will do the job of microplastics and degrade naturally has accelerated.

Scientists believe that “silk proteins” contain solutions that meet this need. As a result of studies conducted with silk proteins, it is expected to replace a synthetic polymer with a biodegradable equivalent and achieve the same, if not better, performance. Silk proteins are non-toxic, biocompatible, meaning they can be degraded in the body, making them safe for food and medical use. Experts are making hopeful statements for the future of silk-based coating materials due to the positive results of the tests conducted and the chemical properties of the material.

The silk protein used in the new alternative material is widely available and cheaper, unlike the high-quality silk threads used to produce fabric. While silkworm cocoons must be carefully dissolved to produce the fine threads needed for fabric, it is explained that cocoons that are not of textile quality can be used for this use, and the cocoons can simply be dissolved using a water-based process.

The new method could enable the utilization of low-quality silk, which cannot be used in textiles and is often thrown away because it has no significant use, and could also enable the upcycling of used, discarded silk fabrics.

It is expected that with the spread of this method, there will be a need for silk production in addition to high-quality fabric production, and thus silk production will increase in other regions other than China, which has a monopoly in silk production. Because bulk silk is used for this process and high quality is not required.

Silkworm breeding and silk production is an income-generating and completely environmentally friendly activity that is carried out intensively by women. Increasing the areas where silk is used outside of textiles is important for sustainable development, environmental protection and reducing women's poverty.

Although silk proteins will not completely solve the problem of microplastic use, this development, which combines agricultural and industrial production to reduce climate change and pollution, stands out as a guiding and sustainable opportunity in the face of major challenges such as environmental pollution and climate change.

https://news.mit.edu/2022/silk-alternative-microplastics

Many thanks to Dear Meral Ünal from Good4Trust for sharing the relevant article.