50 Fun Facts About Polymers

Which everyday product uses sodium polyacrylate, a polymer that soaks up hundreds of times its weight in water?

Baby diapers became ultra-thin once this polymer let makers use only a fraction of the bulky fluff pulp. The powder swells into a gel as it drinks.

Rubber got its English name after chemist Joseph Priestley noticed the material was good at removing what?

Pencil marks had been erased with crustless bread until then, so a springy lump that rubbed them off paper was simply called a rubber.

Which synthetic polymer, first sold as toothbrush bristles in 1938, later caused shop stampedes when used for stockings?

Nylon stockings sold 64 million pairs in their first year, then vanished from shops as wartime production switched to parachutes and tents.

Which slippery polymer, discovered by accident by DuPont chemist Roy Plunkett, now coats non-stick frying pans?

Teflon turned up when a bottle of gas meant for making refrigerants stopped flowing; sawn open, it was lined with a waxy white solid that was oddly slippery.

Which polymer fibre, developed by DuPont chemist Stephanie Kwolek in 1965, is woven into bullet-resistant vests?

Kevlar is five times stronger than steel for its weight, yet its first commercial job was replacing steel in racing tires.

Which country issued the world's first modern polymer banknotes in 1988, for its bicentennial year?

Australia had switched its whole currency to polymer by 1996, because the plastic notes last far longer than paper ones.

Which golden gem, a natural polymer formed from fossilised tree resin, sometimes holds prehistoric insects inside?

Amber begins as soft, sticky resin, so ants and other small creatures got stuck in it and were sealed inside as it slowly hardened.

Which white powder is stirred into PVA school glue to tie its long polymer chains together and make slime?

Borax bridges the glue's long molecules, so a runny liquid turns into a rubbery gel. It is a classic elementary school science demonstration.

Which plastic packaging material began in 1957 as a failed attempt by two inventors to make textured wallpaper?

Bubble wrap flopped as wallpaper for Alfred Fielding and Marc Chavannes, so Fielding co-founded Sealed Air in 1960 to sell it as padding instead.

Which toy maker has moulded its pieces from the tough plastic ABS ever since 1963?

Lego heats ABS to about 232 °C until it is like dough, then moulds it so precisely that bricks from 1958 still snap onto new ones.

Which term names a single small molecule, such as propylene, that links with thousands like it to form a polymer chain?

Monomer molecules hook together like paper clips joined into a long chain, in a reaction that chemists call polymerization.

The word polymer was built from two Greek roots, poly and meros, that together carry which meaning?

Many parts is the literal sense, and Jöns Jacob Berzelius coined the word in 1833, long before chemists could show what such giant molecules looked like.

Which natural polymer, the most abundant on Earth, stiffens plant stems and makes up over 90% of cotton fibre?

Cellulose cannot be digested by humans, so it passes through as dietary fibre, while cows and termites rely on gut microbes to break it down.

Which natural polymer, twisted into a double helix, carries the genetic instructions inside living cells?

DNA is built from just four kinds of repeating unit, called nucleotides, and the order of those four spells out every gene.

Proteins are natural polymers whose long chains are built from about 20 different kinds of which small molecule?

Amino acids join through peptide bonds, and Frederick Sanger proved the chains are straight rather than branched when he decoded insulin.

Which milky fluid, tapped from the bark of the Pará rubber tree, is the raw source of natural rubber?

Latex is a plant's defence against being eaten, and about one flowering plant in ten makes it, including poppies and milkweeds.

Which element did Charles Goodyear cook with natural rubber in 1839, making it far tougher and more durable?

Sulfur ties rubber's long chains to one another, and the process was named vulcanization after Vulcan, the Roman god of fire.

Which plastic of 1907, moulded into early telephones and radios, was the first made entirely from synthetic ingredients?

Bakelite made its inventor Leo Baekeland famous, and because it resists heat and carries no current it turned radios and telephones into household goods.

Which plastic is puffed up with gas to make white packing peanuts and takeaway foam cups?

Polystyrene foam is 95 to 98 percent air, which makes it a fine heat insulator and so light that it blows around as litter.

Which natural polymer fibre is unwound from the cocoons spun by mulberry-eating moth caterpillars?

Silk is mostly the protein fibroin, and traces of it found in ancient Chinese tombs date back about 8,500 years.

Which plastic, the most widely produced in the world, is used for carrier bags, bin liners and squeezy bottles?

Polyethylene only became practical in 1933, when chemists at Britain's ICI squeezed ethylene gas under huge pressure and found, by accident, a white, waxy solid.

Which plastic, known by a three-letter abbreviation, is used for drain pipes, window frames and records nicknamed vinyl?

PVC is naturally rigid, as in pipes and window frames, and only turns bendy enough for flooring or cable coating when softening plasticizers are mixed in.

Which plastic, stamped with recycling code 1, is used for most clear bottles of fizzy soft drinks?

PET bottles were invented in 1973 by Nathaniel Wyeth at DuPont; the plastic soaks up flavours, so refillable ones are given a sniffer test.

Which synthetic fibre is brushed into soft fleece for jackets and blended with cotton to resist wrinkles?

Polyester fleece was developed in 1979 by Malden Mills, whose boss chose not to patent it, so cheap versions quickly spread around the world.

Which rubbery, heat-proof polymer is used for flexible baking moulds, bathroom sealant and kitchen spatulas?

Silicone is unusual among polymers because its backbone is an inorganic chain of alternating silicon and oxygen atoms, with no carbon in the spine at all.

Which synthetic rubber, invented at DuPont in 1930, is foamed to make the wetsuits worn by divers and surfers?

Neoprene first went on sale as DuPrene, and early batches smelled so foul that the way it was manufactured had to be changed.

Which stretchy fibre, invented at DuPont in 1958, can be pulled to five times its length and still spring back?

Spandex is an anagram of the word expands, which is exactly what the fibre does; in continental Europe it goes by the name elastane.

Which clear plastic, sold as Plexiglas and Perspex, formed the cockpit canopies of Second World War aircraft?

Acrylic also went into wartime submarine periscopes and gun turrets, and the first clear sheets were trademarked as Plexiglas in 1933.

Which natural polymer, stored by plants as an energy reserve in potatoes and rice, turns blue-black with iodine?

Starch is the most common carbohydrate in the human diet, and the instant colour change with iodine is a favourite classroom test for it.

Which simple sugar is the only building block of glycogen, the branched polymer that stores energy in the human liver?

Glucose units pack about 30,000 to a single glycogen granule, and plants chain the very same sugar into their own storage and structural polymers.

Which tough protein polymer makes up human hair and fingernails as well as bird feathers and horses' hooves?

Keratin is also what rhino horn is made of, so the horn that poachers kill for is chemically much like a fingernail.

Which natural polymer forms the hard outer shells of crabs, lobsters and beetles, as well as the cell walls of fungi?

Chitin is made by living things at a rate of about a billion tons a year, and seafood factories extract it from discarded shrimp and crab shells.

Which protein polymer, the most abundant in mammals, gives strength to skin, tendons, cartilage and bone?

Collagen makes up 25 to 35 percent of a mammal's protein, and breaking it down with heat gives the gelatin in jelly desserts.

Which plant polymer, plentiful in apples and citrus peel, is the gelling agent that makes jam set?

Pectin is scarce in soft fruits such as strawberries, cherries and grapes, so jam-makers add a powder of it extracted from citrus fruit.

Which natural resin, secreted by a tiny insect on trees in India and Thailand, was pressed into 78 rpm records?

Shellac takes somewhere between 50,000 and 300,000 insects to yield one kilogram, and because it is edible it still glazes sweets and pills.

Which early plastic, once used for nearly all cinema film and table tennis balls, is still made into guitar picks?

Celluloid catches fire so easily that it could ignite in a hot projector beam, which is why safety film replaced it in the 1950s.

A $10,000 prize of 1863 for a billiard-ball material to replace which costly animal product spurred early plastics?

Ivory was expensive and feared to be running short, so Michael Phelan put up the reward that set the inventor John Wesley Hyatt experimenting.

The Pará rubber tree, the source of nearly all natural rubber, is native to which great river basin?

Amazon cities such as Manaus grew rich on a rubber boom until 70,000 seeds were smuggled out in 1876 and plantations sprang up in British colonies.

Which word describes materials that soften every time they are heated, so they can be melted down and remoulded?

Thermoplastic materials can be melted and reshaped again and again, which makes them far easier to recycle than plastics that set hard for good.

Which German chemist won the 1953 Nobel Prize for showing that polymers are giant chain molecules?

Hermann Staudinger made the claim in 1920, when leading chemists insisted such materials were only small molecules clumped together.

Which treat, once made from the tree sap chicle, now owes its texture to synthetic polymers such as butyl rubber?

Chewing gum took off in the 1860s after the Mexican general Santa Anna brought chicle to New York, hoping it would sell as a rubber substitute.

Which household adhesive, based on cyanoacrylate, sets in seconds because traces of water turn it into polymer chains?

Superglue was stumbled on in 1942 by a team led by Harry Coover, who rejected it at first because it stuck to everything it touched.

Most everyday plastics start out as chemicals refined from which raw material?

Crude oil and natural gas supply nearly all plastics, though a growing minority, such as the PLA used for compost bags, are made from plants.

Czech chemist Otto Wichterle used a water-loving polymer gel in 1961 to make the first soft versions of which item?

Contact lenses of the soft kind were first spun on his kitchen table at Christmas, on a machine built from a children's construction kit and a bicycle dynamo.

What name is given to a polymer built from two or more different building blocks, such as ABS plastic?

Copolymer chains let chemists blend properties: rubbery sections soak up the energy of a knock, so the finished plastic is much less brittle.

Which type of polymerization releases a small molecule such as water every time two building blocks join together?

Condensation reactions build the body's proteins too, shedding one molecule of water for every new link added to the growing chain.

What name is given to plastic fragments under five millimetres across that now turn up in oceans, soil and food?

Microplastics come from litter breaking up and from everyday wear, such as tyres shedding dust on roads and synthetic clothes shedding fibres in the wash.

The 2000 Nobel Prize in Chemistry honoured the discovery that certain plastics can do what, almost like a metal?

Plastics that conduct electricity now light up OLED screens, a use nobody had in mind when polyacetylene was first made conductive in 1977.

Which bouncing, stretchy toy sold in a plastic egg was created during wartime research into a rubber substitute?

Silly Putty bounces when dropped yet breaks if struck sharply, and a lump left alone slowly flows out into a puddle.

Scottish chemist Charles Macintosh glued natural rubber between two layers of cloth to invent which garment?

Raincoat fabric was his 1824 breakthrough, and in Britain a waterproof coat is still called a mackintosh, spelled with a k he never used.