New Plastic Dissolves Completely in Seawater to Combat Ocean Pollution
Wageningen, Thursday, 23 July 2026.
Wageningen researchers developed a novel plastic that completely dissolves in seawater within 30 minutes while remaining intact in fresh water, offering a breakthrough for marine conservation.
Molecular Engineering for Ocean Protection
The groundbreaking innovation was developed by researcher Julian Engelhardt at Wageningen University & Research in the Netherlands, specifically within the Organic Chemistry, Physical Chemistry and Soft Matter, and WFBR departments [1]. Engelhardt, who successfully defended his PhD thesis on May 22, 2026, succeeded in creating “saloplastics” (or salopolymers) that utilize molecular charges to dissolve in seawater by breaking into individual chains [1]. In an experiment conducted on July 22, 2026, Engelhardt demonstrated this unique property by placing the plastic in two separate beakers: one containing fresh water and the other containing artificial seawater made of table salt dissolved in water [1]. Within ten minutes, the plastic submerged in the salt water had partially dissolved, and within 30 minutes, it had completely vanished, while the piece in fresh water remained entirely intact [1].
This rapid dissolution addresses a severe global ecological crisis, as current estimates indicate that approximately 11 million tons of plastic enter the world’s oceans every year [1]. To ensure that the dissolved material does not persist as a pollutant, Engelhardt chemically modified the plastic’s molecular backbone with oxygen atoms via ester linkages [1]. This molecular structure, which is highly similar to polylactide (PLA), makes the polymer chains susceptible to biological degradation by both water and marine microorganisms [1]. While Engelhardt has successfully proven the seawater-solubility phase, future research is still required to experimentally verify the subsequent biological degradation phase of these salopolymers [1].
Niche Ecological Applications and Scaling Challenges
Despite the promise of salopolymers, transitioning this laboratory breakthrough into a mass-market commercial product presents significant hurdles. During his doctoral research, Engelhardt was only able to produce tens of grams of the salopolymer material [1]. Furthermore, because the material’s molecular building blocks require additional chemical processing to make them sensitive to salt, and because the plastic remains highly sensitive to atmospheric humidity, it is not currently suitable for standard consumer packaging [1].
Instead, plans for future development target highly specialized niche applications, such as agricultural films or structural matrices for coral reef restoration [1]. The potential for marine conservation is particularly evident in coral reef restoration projects. Engelhardt envisions embedding young, vulnerable corals into a protective structural matrix composed of salopolymers [1]. This temporary mold would provide vital physical stability in the ocean before slowly dissolving over time, leaving behind only the established coral without any residual adhesive or plastic waste [1].
Plantymeer: A Complementary Plant-Based Alternative
While salopolymers offer a solution for marine-specific environments, Wageningen researchers have also collaborated with scientists from Amsterdam and China to address the broader demand for sustainable, land-based biodegradable plastics [2]. In a study published in Nature Communications on July 22, 2026, the international team detailed the development of “plantymeer” (or plantymer), a robust, biodegradable plastic derived from zein, a protein found in maize [2]. Led by Associate Professor of Physical Chemistry and Soft Matter Renko de Vries and sustainable plastic technology researcher Wouter Post, the team utilized a silk-inspired design to manufacture a material that is both strong and highly biodegradable [2].
The production of plantymeer avoids synthetic chemical additives by dissolving zein in an ethanol-water mixture to form a viscous phase, which is then subjected to mechanical forces like extrusion or rolling [2]. This mechanical action coaxes the protein chains to transition from alpha-helices to beta-sheets, creating strong physical cross-links similar to those found in natural animal proteins [2]. The resulting transparent film, comparable in thickness to heavy-duty trash bags, exhibits mechanical strength approaching that of metal and easily outperforms traditional polyethylene [2].
Comparing Performance and Commercialization Paths
In terms of water resistance, plantymeer absorbs only 25% of its weight in water after one hour [2]. This performance vastly outperforms soy-based plastics, which absorb 175% of their weight—meaning soy-based alternatives absorb 7 times more water than plantymeer [2]—though it still lags behind traditional PET, which absorbs a mere 0.1% [2]. Unlike conventional plastics that persist for centuries, plantymeer undergoes complete biological degradation within four weeks without leaving harmful microplastics behind [2].
According to researcher Wouter Post, this rapid, clean degradation makes plantymeer an exceptionally promising alternative for single-use items like disposable cutlery, plates, and straws, which face increasingly strict regulatory restrictions across Europe [2]. However, like the salopolymer project, plantymeer is still in its early stages, with current production capabilities limited to approximately 1 square meter of film [2]. To scale up production responsibly, researchers are actively investigating alternative, non-food feedstocks, such as poultry feathers and brewery waste streams, to ensure the technology does not compete with global food supplies [2].