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Plastic, rubber, and many other useful materials are made of polymers — long chains arranged in a cross-linked network. At the molecular level, these polymer networks contain structural flaws that weaken them.

Several years ago, MIT researchers were the first to measure certain types of these defects, called “loops,” which are caused when a chain in the polymer network binds to itself instead of another chain. Now, the same researchers have found a simple way to reduce the number of loops in a polymer network and thus strengthen materials made from polymers.

Numerous hazardous substances seep from landfills into soil and groundwater, threatening human health and the environment. However, current methods for monitoring these substances are cumbersome and can create additional hazardous chemicals. 

Scientists have found that a caterpillar commercially bred for fishing bait has the ability to biodegrade polyethylene: one of the toughest and most used plastics, frequently found clogging up landfill sites in the form of plastic shopping bags.

About a thousand times a day, thunderstorms fire off fleeting bursts of some of the highest-energy light naturally found on Earth. These events, called terrestrial gamma-ray flashes (TGFs), last less than a millisecond and produce gamma rays with tens of millions of times the energy of visible light. Since its launch in 2008, NASA's Fermi Gamma-ray Space Telescope has recorded more than 4,000 TGFs, which scientists are studying to better understand how the phenomenon relates to lightning activity, storm strength and the life cycle of storms.

Brown University researchers have developed a new composite catalyst that can perform four separate chemical reactions in sequential order and in one container to produce compounds useful in making a wide range of pharmaceutical products.