Amazing Modern Materials

Multi-Demonstration Kit


Material scientists study the chemical structure and properties of substances. They also investigate how the structure and properties change through chemical reactions. Through these investigations new materials are constantly being introduced into society. One “small” area of material science is nanoscience, or nanotechnology which is the study of particles whose sizes are measured in nanometers. These nanoparticles have different properties than their larger bulk material. Even though nanotechnology often has us thinking about electronics, not all nanomaterials are manmade. There are many plants and animals that are able to create nanomaterials. Another area of material science relates to specially made alloys. Nitinol wire is a nickel–titanium alloy with unique memory properties. Introduce your students to three amazing modern materials!

This set of three demonstrations includes:

  1. Ferrofluid—A magnetic fluid created by extremely small Fe3O4 particles. Dramatically demonstrate to your students the unique physical properties of ferrofluid and how its magnetic nanoparticles respond to a magnetic field.
  2. Liquid Crystals—Liquid crystals are compounds or mixtures that behave as both a liquid and a crystal. Liquid crystal molecules move independently like a liquid and also organize themselves like a crystalline solid. Show students how temperature changes the molecular alignment of the crystals creating different colors at various temperatures. Applications include liquid crystal displays (LCD) for laptops, optical imaging, and whimsical items such as mood rings and love meters.
  3. Nitinol Wire—Nitinol wire is a nickel–titanium metal alloy that has a “memory.” The crystal structure exists in different phases or shapes at distinct temperatures. The crystal structure is easily deformed at cool temperatures. At warm temperatures the Nitinol metal contracts like a muscle and the crystal structure returns to its original shape. Construct the desired shape of the nitinol wire in cold water, place it into hot water and watch it quickly and forcefully spring back into its original shape!


  • Nanotechnology
  • Magnetic properties
  • Colloids vs. solutions
  • Liquid crystals
  • Diffraction
  • Metal alloys
  • Crystal structures


Demonstration I. Ferrofluid
A magnetic liquid, also known as a ferrofluid, may seem like a space-age concept. That’s because it is—the idea was conceived by NASA in the 1960s to control the flow of liquid fuels in space! Ferrofluid consists of nano-sized magnetic particles suspended in a liquid. This activity provides some exciting ways to demonstrate the unique properties of ferrofluid.

Demonstration II. Liquid Crystals
Combine two clear liquids and heat them, then watch as the mixture produces vivid color changes from blue to green to red as it cools. From skin mapping to circuit board testing to mood rings, liquid crystals have amazing modern applications. Liquid crystals have properties that are in-between those of solids and liquids—molecules move independently as in a liquid, but they also tend to orient or align themselves like a crystalline solid. The alignment of the molecules changes with temperature and produces fascinating color changes. A simple introduction to the world of nanotechnology!

Demonstration III. Nitinol Wire
See a “live” wire snap back into its remembered shape when it is put into hot or cold water.

Experiment Overview

Demonstration I. Ferrofluid
The purpose of this activity is to demonstrate the unique physical properties of ferrofluid and how its magnetic nanoparticles respond to a magnetic field.


Demonstration I. Ferrofluid
Ferrofluid, 5 mL*
Iron filings, 3 g
Water, tap, 3 mL
Bolt and wing nut to fit, steel, small
Magnet, neodymium
Pennies, 2
Petri dishes, small disposable, 3
Pipet, Beral-type, thin-stem
Plastic bag, resealable
Projection camera (optional)
Tape, masking

Demonstration II. Liquid Crystals
Cholesteryl oleyl carbonate, C46H80O3, 1.2 g*
Cholesteryl pelargonate, C36H62O2, 1.1 g*
Aquarium thermometer*
Background surface, black
Balance, 0.1-g precision
Contact paper, 20 cm x 20 cm*
Hot water bath (80–90 °C) or hair dryer
Lamp with diffuser
Overhead projector (optional)
Tape, clear
Vials, with screw tops, 2*
Weighing dishes, 2
Wood splints, 2

Demonstration III. Nitinol Wire
“Live” wire (Nitinol wire, pronounced “night ’n all” )*
Beaker of ice water
Beaker of near boiling water
Bunsen burner (or candle)
Pliers or tongs
*Materials included in kit.

Safety Precautions

Ferrofluid is a skin and eye irritant and will stain skin and fabric. Cholesteryl oleyl carbonate and cholesteryl pelargonate are skin and eye irritants and may cause respiratory and digestive tract irritation. Avoid contact of all chemicals with skin and eyes. Wear chemical splash goggles, chemical-resistant gloves and a chemical-resistant apron. Wash hands thoroughly with soap and water before leaving the laboratory. Follow all laboratory safety guidelines. Please review current Safety Data Sheets for additional safety, handling and disposal information.


Please consult your current Flinn Scientific Catalog/Reference Manual for general guidelines and specific procedures, and review all federal, state and local regulations that may apply, before proceeding. Ferrofluid used in the demonstrations as written may be returned to the bottle and stored for future use. Materials coated in ferrofluid may be wiped clean with paper towels and the paper towels thrown away in the regular trash according to Flinn Suggested Disposal Method #26a. Cholesteryl oleyl carbonate and cholesteryl pelargonate may be disposed of according to Flinn Suggested Disposal Method #26a. If not overheated or overextended (which may damage the wire’s unique crystal structure), the nitinol wire can perform for over 20 million cycles.

Prelab Preparation

Demonstration I. Ferrofluid

Before handling ferrofluid, please read the Tips section.

  1. Place a penny in the bottom of each of two small disposable Petri dishes.
  2. Place a neodymium magnet in a resealable plastic bag under one Petri dish.
  3. Using a disposable pipet, carefully add enough ferrofluid so the ferrofluid forms a dome with spikes over the magnet. Note: Do not add too much ferrofluid or the dome of fluid will mound up too high and not show any spikes.
  4. Keeping the magnet in place under the Petri dish, place the cover on the dish and seal around the circumference of the dish with masking tape. Press the tape firmly against the dish for a good seal.
  5. Carefully remove the magnet from underneath the dish. Note: Once the ferrofluid has been added to the dish it is important to keep the dish level. Ferrofluid will coat the inside surface, and if it comes in contact with the cover of the dish, observations will be difficult, if not impossible. If this happens, let the covered dish stand with a magnet centered underneath until the ferrofluid flows back to the bottom of the dish. This may take up to 10 minutes before the dish is transparent enough to see through and from 30 minutes up to an hour until more detailed observations may be made.
  6. In the second Petri dish, measure and add 3 g of iron filings and enough tap water to match the level of ferrofluid in the first dish. Note: Iron filings will not rust as quickly in tap water compared to deionized water.
  7. Place the cover on the second Petri dish and tape to seal.

Demonstration II. Liquid Crystals

Low Temperature Liquid Crystal

  1. Weigh out 0.6 g of cholesteryl oleyl carbonate (COC) and transfer to a labeled glass vial.
  2. Weigh out 0.4 g of cholesteryl pelargonate (CP) and transfer to the same glass vial.
  3. Cap the vial and gently heat the vial in a hot water bath or with a hair dryer at a medium setting until the mixture melts.

High Temperature Liquid Crystal

  1. Weigh out 0.5 g of cholesteryl oleyl carbonate (COC) and transfer to a second labeled glass vial.
  2. Weigh out 0.5 g of cholesteryl pelargonate (CP) and transfer to the same glass vial.
  3. Cap the vial and gently heat the vial in a hot water bath or with a hair dryer at a medium setting until the mixture completely melts.

Liquid Crystal “Sandwiches”

  1. Cut four 10 cm x 10 cm squares of clear contact paper.
  2. Peel the backing off one of the squares of contact paper.
  3. Use a wood splint to spread the low temperature liquid crystal mixture on the tacky side of the clear contact paper. Spread the mixture into an approximate 2-inch diameter circle.
  4. Peel the backing off of one other square. With the tacky side down, place the square over the tacky side of the square containing the liquid crystal mixture. Seal all the edges of the contact paper “sandwich,” making sure not to squeeze out the mixture. Label the square 1.
  5. Repeat steps 1–4 for the other liquid crystal mixture. Label it 2.


Activity 1—Compare and Contrast Macro- and Nano-sized Iron Particles

  1. Show students the two prepared Petri dishes and instruct students to record observations about the contents of each dish.
  2. Gently shake the dishes from side to side so students can observe how the contents move. Students should include observations about the relative densities of the penny and the rest of the contents in each dish.
  3. While holding the Petri dish with iron filings in one hand and a neodymium magnet inside a plastic bag in the other hand, slowly and carefully bring the magnet up from below the dish to the center of the bottom of the dish, away from the penny. Instruct students to record observations about any differences they see.
  4. Repeat step 3 with the ferrofluid Petri dish. Note: BE VERY CAREFUL that the magnet stays under the Petri dish and away from the outer edge of the dish. Bringing the magnet too close to the side of the dish may cause the ferrofluid to leak out.
  5. Repeat step 3 with the first Petri dish and move the magnet around so it moves from next to the penny to under the penny. Instruct students to record observations.
  6. Repeat step 5 with the ferrofluid Petri dish.

Activity 2—Ferrofluid Sculptures

  1. Obtain a clean, small disposable Petri dish, a small steel bolt and a steel wing nut to fit the bolt.
  2. Thread the wing nut onto the end of the bolt just enough so the nut remains on the bolt.
  3. Place a neodymium magnet in a resealable plastic bag and set it flat on the demonstration table.
  4. Center the Petri dish on top of the magnet.
  5. Place the nut and bolt assembly in the center of the Petri dish over the magnet (see Figure 1).
  6. Have students watch as you slowly and carefully dispense ferrofluid drop-wise onto the wing nut and bolt until 1–2 mL have been dispensed.
  7. Instruct students to record their observations. Note: Students close to the demonstration table should wear chemical splash goggles.

Demonstration II. Liquid Crystals

Light Reflection and Transmission

  1. Take the liquid crystal sandwich 2 (the high temperature liquid crystal) and show it to the students. Press the square in your hands to heat the mixture.
  2. Place the square in front of or on top of a dark surface. Observe the reflected colors that are seen, and record all observation, including how the colors change over time, on the demonstration worksheet.
  3. Heat the square again, then hold the square in front of a white light source and view the transmitted colors that are seen. Record the colors and color changes over time on the demonstration worksheet.
  4. Repeat steps 1–3 using the other liquid crystal mixture.

Liquid Crystals as Temperature Indicators

  1. Place a strip of clear tape on the top center of each liquid crystal sandwich.
  2. Tape the squares next to each other (side by side) on a dark surface.
  3. Gently heat the “sandwiches” with a hair dryer until the liquid crystal mixtures are clear and colorless.
  4. Observe and record the sequences of color changes for the two liquid crystal mixtures.

Transition Temperature

  1. Remove the backing from the thermometer strip and attach it to the contact paper in sandwich 2, next to the liquid crystal mixture.
  2. Pass the liquid crystal sandwich around the class. Tell the students to record the transition temperatures of the liquid crystal for the appearance of blue reflected color and the green reflected color.

Demonstration III. Nitinol Wire

Part A. See the Wire Remember its Straight Shape

  1. Start with the “live” wire in a “straight” form.
  2. Hold one end of the wire and place it into the beaker of ice water until it is thoroughly chilled.
  3. Remove the wire and quickly use your hands to bend it into crazy shapes (or better yet, if you can, bend the wire while it is still in the ice water).
  4. While holding one end of the bent nitinol wire, carefully dip it into the near-boiling water. The wire should instantaneously pop back straight again. Amazing that a piece of wire will “remember” and return to its original straight shape (see Figure 2).

Part B. “Train” the Wire to Remember a New Shape

  1. Starting with the straight wire, use your hands or pliers to bend the wire at room temperature into a desired shape.
  2. While firmly holding the wire in this shape with pliers or tongs (you may need 2 pairs), heat it in a Bunsen burner flame (or candle flame) until it is just slightly red. The wire will at first “fight” and want to straighten out. (You must “train” it.) Note: Overheating will not help in this procedure and may actually damage the wire.
  3. Allow the wire to cool to room temperature, still holding it in its “trained” shape.
  4. Chill the wire by dipping it into ice water. Remove the wire from the ice water and immediately straighten it out.
  5. Using tongs, dip the wire into a near-boiling water bath.
  6. The wire should “remember” the bent shape in which you “trained” it and form back into that shape.
  7. Both Parts A and B may be repeated millions of times if the wire’s unique crystal structure is not damaged by overextending or overheating.

Student Worksheet PDF


Teacher Tips

  • Ferrofluid can be messy. Please read the handling tips.

    • Always wear chemical splash goggles, chemical-resistant gloves and a chemical-resistant apron when working with ferrofluid.
    • Covering the work surface with newspaper or paper towels during preparation and cleanup is recommended.
    • When dispensing ferrofluid, gently squeeze the pipet bulb and aim carefully so the ferrofluid does not splatter.
    • Keep any magnets inside a plastic bag to protect them from coming in contact with the ferrofluid.
    • Keeping a strong magnet in a resealable bag under the Petri dish during preparation will help contain the ferrofluid in the center of the dish, preventing it from coating the sides or top of the dish. Remove the magnet when necessary for student observations.
    • Use caution when bringing a magnet close to a dish containing ferrofluid. Ferrofluid may “leap” from the dish if the magnetic field is too close. Always bring a magnet to the dish from below and keep it centered under the dish.
    • Excess ferrofluid may be returned to the bottle and reused. Cap the bottle tightly to prevent evaporation.
    • Remember to wear appropriate personal protective equipment during cleanup. Remove objects from ferrofluid with nonmagnetic forceps and throw away or wipe clean with paper towels.

  • Use a projection camera or a document camera so all students may easily see the demonstrations at the same time.
  • Iron filings made from a non-rusting alloy are available from Flinn Scientific, Catalog No. I0059. Note: Even non-rusting iron filings will eventually rust if stored in water. After completing Activity 1, absorb the water in the Petri dish with paper towels and spread the filings out on a clean paper towel to dry.
  • Repeat Activity 1 without the penny and experiment with other magnet shapes. Magnetic rings and flat, flexible vinyl refrigerator magnets make interesting patterns with the ferrofluid. Place the magnetic side of a vinyl magnet against the bottom of the Petri dish and place a stronger magnet under the vinyl magnet to make the magnetic lines of force more noticeable.
  • Experiment with other magnetic objects, such as nails, screws, staples and paper clips, to create other ferrofluid sculptures. See how the shape and size of the objects as well as the amount of ferrofluid affect the magnetic patterns.
  • Solutions and colloids differ in the size of the particles that are dispersed in the liquid phase. The following table summarizes the properties of solutions, colloids, and suspensions. Notice that the particle size range for each type of mixture is just that, a range, and not an absolute or fixed value.


  • Make your own ferrofluid with the Flinn Scientific Ferrofluid Nanotechnology Demonstration Kit, Catalog No. AP7118.
  • This kit contains enough chemicals and materials to create two liquid crystal “sandwiches” that can be stored and reused multiple times: 1.2 g of cholesteryl oleyl carbonate, 1.1 g of cholesteryl pelargonate, a 20" x 20" sheet of contact paper, an aquarium thermometer and two vials.
  • Prepare a hot water bath for use in the Preparation section. The water does not need to be boiling—the melting point of cholesteryl oleyl carbonate is ~ 20 °C, that of cholesteryl pelargonate 74–77 °C.
  • Figure 3 shows a graph of the reflected color transition temperatures for liquid crystal mixtures as a function of the percent composition of cholesteryl oleyl carbonate (COC).


    Cholesteryl oleyl carbonate has a lower transition temperature than cholesteryl pelargonate.

  • The liquid crystal sandwiches can be placed on an overhead projector to view the transmitted colors. If the projector surface heats the liquid crystals above their transition temperature, place the square on top of a Petri dish to prevent the square from being heated by the projector.
  • The two vials each contain a small portion of liquid crystal. Pass the vials around the classroom. Have each student use his or her hands to heat up both vials simultaneously, then set them on their desks to view the transition colors for each mixture.

Correlation to Next Generation Science Standards (NGSS)

Science & Engineering Practices

Developing and using models
Obtaining, evaluation, and communicating information
Analyzing and interpreting data
Using mathematics and computational thinking
Constructing explanations and designing solutions

Disciplinary Core Ideas

MS-PS1.A: Structure and Properties of Matter
MS-PS2.A: Forces and Motion
MS-ETS1.B: Developing Possible Solutions
MS-PS2.B: Types of Interactions
MS-PS3.A: Definitions of Energy
HS-PS1.A: Structure and Properties of Matter
HS-PS2.B: Types of Interactions
HS-PS3.A: Definitions of Energy
HS-PS4.A: Wave Properties
HS-ETS1.C: Optimizing the Design Solution

Crosscutting Concepts

Cause and effect
Systems and system models
Energy and matter
Structure and function

Performance Expectations

MS-PS1-2. Analyze and interpret data on the properties of substances before and after the substances interact to determine if a chemical reaction has occurred.
MS-PS3-1. Construct and interpret graphical displays of data to describe the relationships of kinetic energy to the mass of an object and to the speed of an object.
MS-PS2-5. Conduct an investigation and evaluate the experimental design to provide evidence that fields exist between objects exerting forces on each other even though the objects are not in contact
MS-PS4-2. Develop and use a model to describe that waves are reflected, absorbed, or transmitted through various materials.
HS-PS1-3. Plan and conduct an investigation to gather evidence to compare the structure of substances at the bulk scale to infer the strength of electrical forces between particles.
HS-PS4-5. Communicate technical information about how some technological devices use the principles of wave behavior and wave interactions with matter to transmit and capture information and energy.
HS-PS2-6. Communicate scientific and technical information about why the molecular-level structure is important in the functioning of designed materials.

Sample Data


Answers to Questions

  1. Draw a picture showing ferrofluid and its reaction to a magnetic field. Label all parts of the diagram, including the location of the magnet.
  2. During the ferrofluid demonstration the magnet is placed inside a resealable bag. What purpose does the bag serve?

    The bag prevents the ferrofluid from directly attaching itself to the magnet. Once the ferrofluid comes in contact with the magnet, it is very difficult to remove.

  3. In the liquid crystal demonstration, compare the color changes when the liquid crystal mixtures are viewed for reflected light—against a black background—and for transmitted light, in front of a light source.

    For reflected light, the color transitions are violet → blue → green → yellow → orange → red.

    For transmitted light, the color transitions are yellow → orange → pink → blue → violet.

  4. In the nitinol wire demonstration, how does temperature play a role in the shape of the wire?

    The alloy has crystal structures that have different shapes at different temperatures. When cooled the crystal structure is easily changed and returns to its original shape when heated in near-boiling water.


Demonstration I. Ferrofluid
Nanoscience or nanotechnology involves the preparation, characterization, and uses of nano-sized particles having dimensions in the 1–100 nm range (1 nm = 1 x 10–9 m). Nanoparticles have unique physical and chemical properties that are very different from the macroscopic properties of traditional or “bulk” solids. Many of these properties have taken on special importance in recent years as the applications of nanotechnology have been intensively studied. In particular, the electronic, magnetic, and optical properties of nanoparticles have proven to be very useful in the creation of new products using nanotechnology.

Magnetic liquids, also known as ferrofluids, are stable colloids containing nanocrystalline magnetite particles that are about 10 nm in diameter. In the absence of an external magnetic field, the ferrofluid flows and behaves like a “normal” albeit viscous liquid. When a magnet is brought near a dish or vial containing the ferrofluid, the “solid” nanoparticles are attracted to and will “follow” the magnet around the dish or vial. As the magnetite nanoparticles become more concentrated at the magnetic pole, the ferrofluid mounds up, becoming more dense and a penny “floats” on top of the dome. The ferrofluid forms interesting three-dimensional shapes or structures as the magnetic moments of the nanoparticles align themselves with the external magnetic field. Noticeable peaks or spikes in the ferrofluid correspond to the magnetic field lines (see Figure 4). When a magnetic object such as a bolt is placed in a magnetic field, the bolt becomes a temporary magnet with the strongest part of the magnetic field concentrated at the ends. Thus when ferrofluid is added to the bolt, spikes appear on the end of the bolt

Ferrofluids are more than just an intellectual curiosity. They have innovative commercial or practical applications, including as dampeners or heat sinks in loudspeakers, as seals in high speed computer disk drives, as magnetic inks for laser printers, and even, apparently, as radar-absorbing paints that allow military aircraft to escape radar detection.

Demonstration II. Liquid Crystals
Liquid crystals consist of nano-sized organic compounds that are in a state between liquid and solid compounds. Liquid crystals are partially ordered compounds that float around as in a liquid, but align themselves, to a degree, as in a crystalline solid. Cholesteryl esters are long, cylindrical or rod-like molecules that arrange themselves in a layered helical pattern, similar to a spiral staircase (see Figure 5).
The molecules in each layer line up in a parallel pattern, with each adjacent layer having this parallel pattern slightly rotated. After a certain number of layers and rotations, the molecules in the top and bottom layers are aligned in the same direction. The distance between these layers is called the pitch of the liquid crystal (see Figure 6).
As the liquid crystal heats up, the rotational angle between adjacent layers increases. Since fewer layers are required to realign the top and bottom, the pitch decreases with increasing temperature.

These pitch distances are on the order of magnitude corresponding to visible light wavelengths, that is, 300 nm to 400 nm. Visible light is selectively diffracted by the liquid crystal according to Snell’s Law (Equation 1).
where λ is the reflected wavelength, p is the pitch, θ is the angle with respect to the surface, and n is the mean refractive index. As the temperature increases, the wavelength of visible light decreases. The reflected light changes from yellow (longer wavelength) to green to blue (shorter wavelength) as the liquid crystal is heated, and blue to green to red as it is cooled. The temperature range for these color transitions is different for each liquid crystal compound and mixture of compounds.

If a specific wavelength of light is reflected by the crystal, then all other wavelengths pass through the crystal. If blue is the reflected light, then light transmitted through the crystal is white light minus blue light, which is perceived as yellow. If orange light is reflected, then white light minus orange light, which is seen as blue light, is transmitted. When a liquid crystal square is viewed against a black background and then in front of a light source, the reflected color is observed first, followed by its complementary color.

Demonstration III. Nitinol Wire
Nitinol wire is part of a class of metals known as Shape Memory Alloys (SMAs). These alloys have different crystal structure phases that form at distinct temperatures. The crystal structure is easily deformed at cool temperatures (see A), and then when heated, the solid state structure returns to its original arrangement with great speed and force (see B).

The live wire is a nickel–titanium alloy and thus is given the acronym Nitinol. Nitinol consists of nearly equal percentages of the two metals and is specially alloyed and annealed to produce a small grained, extremely uniform crystal structure. A difference of less than 1% in composition will change its transition temperature by 150 °C. Therefore, the materials require very careful formulation and processing.

The Shape Memory Effect (SME) of the nickel–titanium alloy was accidentally noticed by William Beuhler and his research team at the U.S. Naval Ordnance Laboratory in 1961. However, the first SME was discovered in 1932 by Arne Ölander, a Swedish researcher, who observed the Shape Memory Effect of a gold–cadmium alloy. During the 1960s and 1970s, other Shape Memory Alloys were found. Researchers around the world studied alloys of titanium, copper, iron and gold which had this newly found property.

The most successful applications have come more recently. Raychem Corporation came out with Shape Memory Alloy pipe connectors that will shrink, thus producing a better seal in jet engines and hydraulic systems. Toki Corporation of Tokyo, Japan, improved nitinol for specific use by electrical activation. At the 1986 International Symposium on SMAs, papers were presented on possible applications including basic alloy research and development, crystal structures, medical applications (such as using SMA wires like electric muscles in robotic or prosthetic devices), product designs and manufacturing studies.

Since not all areas of Shape Memory Alloys have been explored, the research and interest is still growing today.


National Nanotechnology Infrastructure Network, (accessed November 2011).

Lisensky, G. et al., “Colors in Liquid Crystals,” J. Chem. Educ., 2005, 82, 1360A.

Properties of 6 mil BioMetal™ Wire, Mondo-tronics, Inc., Sunnyvale, California, 1987.

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