Team to strengthen bioplastics with cream of tartar?
Marie Donlon | February 20, 2023A study conducted by a team from the Korea Research Institute of Chemical Technology has found that “seasoning” bioplastics with cream of tartar will fortify the material, making the bioplastic appropriate for even more applications such as food packaging.
While most bioplastics available today tend to be on the flimsier side because they are designed to break down easier, the team explore additives as an avenue for strengthening the material.
Merits and limitations of current biodegradable plastics, and the new “food-seasoning”-like synthetic strategy for overcoming the limitations. (Top) Biodegradable and biobased plastics are carbon-neutral and do not generate microplastics that can return through food. (Bottom) The cooking-inspired method transforms a weak bioplastic into a strong and tough one through “seasoning” with a minimal dose of a sustainable additive, namely, citric acid (CA) or tartaric acid (TA), that pinch the chain ends at the molecular level in the amorphous region. It is economical and feasible because it maintains the original processes; in addition, it facilitates and solves the trade-off relationship between mechanical strength, shelf life, and the biodegradation rate of a bioplastic. Source: ACS Sustainable Chemistry & Engineering (2023). DOI: 10.1021/acssuschemeng.2c06247
As such, the team “seasoned" the biodegradable bioplastic poly(butylene succinate) (PBS) with both tartaric acid and citric acid in an attempt to potentially improve the mechanical properties of the bioplastic.
To create the seasoned PBS, succinic acid and 1,4-butanediol were heated with small concentrations of tartaric and citric acid. The team then added titanium(IV) butoxide and subsequently dried the products.
During testing, the researchers found that the two new films were capable of being stretched more than twice as far before breaking, letting through even less oxygen than "unseasoned” PBS. Due to these findings, the team suggested that the new materials could potentially be used for future bags or food packaging.
Further, the team suggested that the two seasoned materials were stronger than several biodegradable plastics and even some petroleum-based products.
The seasoned bioplastics are detailed in an article titled Toward Sustaining Bioplastics: Add a Pinch of Seasoning, which appears in the journal ACS Sustainable Chemistry & Engineering.