The Chemistry of Currency


Dr. Kenneth Lyle, Duke University Department of Chemistryby Gabrielle Hodgins and Dr. Kenneth Lyle, Duke University, Durham NC

The wonders of magnetic ink!

INTRODUCTION

Demonstrating the magnetic ink used in printing US currency has proven to engage audiences of all ages because of its relevance to everyday life.  Nearly everyone has used machines that distribute and/or accept currency but few understand how the machines distinguish between the various denominations.  The key is in the face of each denomination.  Magnetic ink is used in the printing of the currency.  Each denomination has a different face and, therefore, a different magnetic signature.  Similar to a bar code reader, the machines recognize the denomination by its magnetic signature.  A strong magnet, such as a neodymium magnet, can be used to demonstrate the magnetic character of US currency.

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Hydrophilic Polymers TV


EI TV - Educational Innovations BlogIf a picture is worth 1,000 words, a video is surely worth a few million.  Especially when it comes to scientific explanations, a video is a wonderful tool for conveying information to your students in a visual, easy-to-follow manner.

The videos below offer you and your students a glimpse into the world of hydrophilic polymers—where they are today, what new discoveries we’ve made, and where we are headed in the future.

Enjoy!  If you find a video on hydrophilic polymers that you’d like to share with us, please leave a comment!

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Hydrophilic Polymers Lesson


Lesson - Educational Innovations BlogHydrophilic superabsorbent polymers are so much fun to use in the classroom.  Young and older students alike love working with Growing Spheres that expand by more than 300 times their original size.  And who doesn’t love an avalanche of Instant Snow?

We know that the best lessons are those that keep your students engaged in genuine, hands-on scientific exploration.  We believe that students learn more when they’re having FUN… and that’s precisely what happens when you bring any hydrophilic material into your classroom.

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Hydrophilic Polymers in the News


In the News - Educational Innovations Blog

Superabsorbent hydrophilic polymers are everywhere—often, in places we’d never suspect.  Researchers continue to discover new uses for these handy materials:  in concrete, in stainless steel coatings, medical devices, and many other industrial applications.   Truly, they are one of the most fascinating areas of chemical research today.

We have collected below a sampling of news articles about recent developments in the field of SAPs in the hopes that these will inspire conversations with your students about the practical uses of hydrophilic substances.  If you come across an article of interest, please share it with us in the Comments section below.

Happy reading!

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Hydrophilic Polymers Discussion Starters


Discussion Starters - Educational Innovations BlogYour students may already be aware of some ways that hydrophilic polymers are used in our daily lives.  For instance, Sodium Polyacrylate is an essential component of disposable diapers, and Growing Spheres are often used by florists as a soil-free way to store water and keep cut flowers fresh for a long time.

But what else can hydrophilic polymers do?  The answer is, plenty!

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