Silly putty
Silly putty Field(s) of Science: Physics Concepts: polymers, hydrogen bonds, covalent bonds Age: 5-18yrs Grade: 1-12 Duration: 15 minutes Materials Needed: ● 50/50 glue water mix ● Snack sized Ziplocs (1/student) ● Borax in water ● 50mL tube ● 15mL tube ● Food colouring Context Define the concepts Polymer: In simplest terms, a polymer is a long chain of molecules. “poly” means many, “mers” means member. Polymers can be flexible, pliable, and stretchy. A good example of a polymer is spaghetti. When a pile of freshly cooked spaghetti comes out of the hot water and into the bowl, the strands flow like a liquid from the pan to the bowl. This is because the spaghetti strands are slippery and slide over one another. After awhile, the water drains off of the pasta and the strands start to stick together. The spaghetti takes on a rubbery texture. Wait a little while longer for all of the water to evaporate and the pile of spaghetti turns into a solid mass -drop it on the floor and watch it bounce. Covalent bounds : very strong chemical bond between 2 molecules (as they share a pair of electron between the molecules) Hydrogen bounds : the chemical bond between a molecule of hydrogen (H) and another molecule like nitrogen (N), oxygen (O). These hydrogen bonds are not very solid and can be easily broken. Intro questions to ask the classroom Q: What are some examples of polymers? Rubber in erasers, linoleum, synthetic fabrics in clothing (ex. polyester), most plastics (ex polystyrene – CD cases, cell phone covers etc) The history of Silly Putty is quite amusing. In 1943 James Wright, an engineer, was attempting to create a synthetic rubber. He was unable to achieve the properties he was looking for and put his creation (later to be called Silly Putty) on the shelf as a failure. A few years later, a 1 Version date: September 2015
salesman for the Dow Corning Corporation was using the putty to entertain some customers. One of his customers became intrigued with the putty and saw that it had potential as a new toy. In 1957, after being endorsed on the "Howdy Doody Show", Silly Putty became a toy fad. Recently new uses such as a grip strengthener and as an art medium have been developed. Silly Putty even went into space on the Apollo 8 mission. Doing the Activity! ● Give each kid a Ziploc bag and have them hold it open while you add items ● 7mL borax solution MIX WELL BEFORE POURING (using the small 15mL plastic tube) ● 25mL 50/50 glue and water dilution (using the larger 50mL plastic tube) ● 1 or 3 drops of food colouring of their choice ● Have them zip the bag closed and mix everything together with their hands for a few minutes ● It should congeal together after 3-5min of mixing to the point where they can take it out of the bag and play with it in their hands Things to be careful of: ● If they mix too vigorously they can pop the bag open ● It’s easier to mix if they get more air out ● Try not to spill/waste the food colouring What's Happening? The polymers in Silly Putty have covalent bonds within the molecules, but hydrogen bonds between the molecules. The hydrogen bonds are easily broken. When small amounts of stress are slowly applied to the putty, only a few bonds are broken and the putty "flows." When larger amounts of stress are applied quickly, there are many hydrogen bonds that break, causing the putty to break or tear. Many natural and synthetic polymers behave in a similar manner. Polymers are made out of long strands of molecules like spaghetti. If the long molecules slide past each other easily, then the substance acts like a liquid because the molecules flow. If the molecules stick together at a few places along the strand, then the substance behaves like a rubbery solid called an elastomer. Borax is the compound that is responsible for hooking the glue’s molecules together to form the putty-like material.
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Why does it Matter? Many of the plastic bottles, bags, carpets and clothes we used in daily life are polymers. How to Restock the kit? To refill Borax solution: add 4 teaspoons of borax (white powder) to 500mL labelled bottle. Shake well for a few min to dissolve borax in water To refill glue/water: find empty bottle and pour half of full glue bottle into it, fill both bottles to the top with water, put on lid and shake well for a few min to ensure even consistency.
3 Version date: September 2015
salesman for the Dow Corning Corporation was using the putty to entertain some customers. One of his customers became intrigued with the putty and saw that it had potential as a new toy. In 1957, after being endorsed on the "Howdy Doody Show", Silly Putty became a toy fad. Recently new uses such as a grip strengthener and as an art medium have been developed. Silly Putty even went into space on the Apollo 8 mission. Doing the Activity! ● Give each kid a Ziploc bag and have them hold it open while you add items ● 7mL borax solution MIX WELL BEFORE POURING (using the small 15mL plastic tube) ● 25mL 50/50 glue and water dilution (using the larger 50mL plastic tube) ● 1 or 3 drops of food colouring of their choice ● Have them zip the bag closed and mix everything together with their hands for a few minutes ● It should congeal together after 3-5min of mixing to the point where they can take it out of the bag and play with it in their hands Things to be careful of: ● If they mix too vigorously they can pop the bag open ● It’s easier to mix if they get more air out ● Try not to spill/waste the food colouring What's Happening? The polymers in Silly Putty have covalent bonds within the molecules, but hydrogen bonds between the molecules. The hydrogen bonds are easily broken. When small amounts of stress are slowly applied to the putty, only a few bonds are broken and the putty "flows." When larger amounts of stress are applied quickly, there are many hydrogen bonds that break, causing the putty to break or tear. Many natural and synthetic polymers behave in a similar manner. Polymers are made out of long strands of molecules like spaghetti. If the long molecules slide past each other easily, then the substance acts like a liquid because the molecules flow. If the molecules stick together at a few places along the strand, then the substance behaves like a rubbery solid called an elastomer. Borax is the compound that is responsible for hooking the glue’s molecules together to form the putty-like material.
2 Version date: September 2015
Why does it Matter? Many of the plastic bottles, bags, carpets and clothes we used in daily life are polymers. How to Restock the kit? To refill Borax solution: add 4 teaspoons of borax (white powder) to 500mL labelled bottle. Shake well for a few min to dissolve borax in water To refill glue/water: find empty bottle and pour half of full glue bottle into it, fill both bottles to the top with water, put on lid and shake well for a few min to ensure even consistency.
3 Version date: September 2015
