Why glow sticks glow

Rauhut, who was manager of exploratory research at the chemical firm American Cyanamid. Rauhut and his colleague Laszlo J. Bollyky swapped the reactive oxalyl chloride that Chandross used for less reactive and longer-lasting oxalate esters, settling on an aromatic oxalate ester.

American Cyanamid chemists also added a little salicylate base to catalyze the reaction as well as experimented with a rainbow of dyes. In modern glow sticks, rhodamine B produces a radiant red; 9,bis phenylethynyl anthracene gives a green glow; and 9,diphenylanthracene lights up with a blue hue.

While most people associate glow sticks with the novelty market, they also have more serious uses. Today, the government market for glow sticks is considerable, says Donald Schmidt, a senior vice president for Cyalume Technologies , a company that grew out of American Cyanamid. Cyalume provides glow sticks that the US military and Department of Defense use for training exercises and field operations, and glow sticks can save lives.

Flotation vests equipped with the devices, for example, can help rescuers find people lost at sea. When there is a danger of flammable fumes, glow sticks can provide illumination without the risk of ignition. Several of those changes relate to safety. For example, the oxalate esters that were used in glow sticks decades ago produced trichlorophenols—chemicals that could go on to form toxic halogenated dioxins.

To eliminate trichlorophenols, Jacob says, Cyalume turned to trichlorsalicylate oxylate esters, which are safer. The firm also now uses butyl benzoate and triethyl citrate as solvents instead of phthalates , some of which have been identified as endocrine disruptors. Most novelty glow sticks still use phthalates, however, she says.

So the next time you snap a glow stick, take a moment to appreciate the cool chemistry that brightens your night. Contact us to opt out anytime. Contact the reporter. Submit a Letter to the Editor for publication. Engage with us on Twitter. The power is now in your nitrile gloved hands Sign up for a free account to increase your articles. Or go unlimited with ACS membership. Chemistry matters. Join us to get the news you need. Don't miss out.

Renew your membership, and continue to enjoy these benefits. Not Now. Grab your lab coat. Here it's sealed in a glass capsule that cracks open when you bend the plastic stick. Once it's unleashed, H 2 O 2 triggers a chemical chain reaction that puts the glow in the stick. The hydrogen peroxide reacts with these molecules in the outer tube to form a highly unstable compound that quickly breaks down into CO 2 , releasing energy that excites the dyes and produces light.

Scientists developed this process in the early s; American Cyanamid trademarked its version as Cyalume. This supersolvent is also used as a preservative in cosmetics. Here it keeps the colors and oxalate esters flowing and spread throughout the outer tube, so when it's time to crack the inner capsule, your glowie is as rave-ready as you are. Best known for keeping plastics and rubbers pliable, this oily liquid also helps stabilize unstable chemicals like hydrogen peroxide.

Making up nearly 90 percent of the inner capsule, DMP dilutes and preserves the peroxide, extending your glow stick's shelf life all the way to next Halloween. From the original 6" taper glow sticks to glow bracelets, necklaces and are even made into products such as cups, badges, straws and more. All of these products work in the same way. But how do glow sticks glow? Chemiluminesence is a chemical reaction that causes a release of energy in the form of light. To produce this light the electrons in the chemicals become excited and rise to a higher energy level.

To utilise this process glowsticks contain two liquids; hydrogen peroxide and tert-butyl alcohol. When mixed together it is these liquids that create the glow. Fluorescent dyes are also used in the alcohol to alter the colour of the light emitted. One of the liquids is contained in a very fine glass tube that floats within the mixture inside the plastic glow stick product. This is why you must bend a glow stick to make it start glowing.

When the stick bends, the glass vial breaks allowing the two liquids to mix together. The chemical reaction begins immediately resulting in a bright, fantastic glow.

Temperature also affects the intensity of the glow - the warmer it is the brighter the glow but this shortens the total glow duration. The colder it is the glow stick will glow less but will glow for a longer duration.