Thermoset Plastics to Be Made Recyclable

A new method for producing thermoset plastics allows them to break down more easily after use. Thermosets containing rubber used in epoxies, polyurethanes and elastomers are found in many products that need to be durable and heat-resistant, such as cars or power tools. A disadvantage of these materials is that after use they typically cannot be easily recycled or degraded, because the chemical bonds holding them together are stronger than those found in other materials like thermoplastics. MIT chemists have developed a way to modify thermoset plastics with a chemical linker that makes the materials much easier to break down, while still maintaining the mechanical strength that makes them so useful. In a study published in Nature today, researchers demonstrated that they could produce a degradable version of a thermoset plastic called pDCPD, grind it into a powder, and use the powder to make more pDCPD. They also proposed a theoretical model suggesting that their approach could be applied to a wide variety of plastics and other polymers such as rubber. Jeremiah Johnson, a professor of chemistry at MIT and senior author of the study, said: "This work establishes a fundamental design principle that we believe is general for every type of thermoset with this basic architecture."   Source: MITNews