Curtis Taylor

Potentially Reusable Microporous Polymers Cling to Surfaces With Variable Degrees of Adhesiveness

These adhesive films utilize a microporous shape memory polymer to perform switchable, dry adhesion useful in situations requiring two or more levels of adhesion. Dry adhesives are part of the pressure-sensitive adhesives market, which analysts expect to reach $9.5 billion by 2024. Dry adhesive materials stick to surfaces without the use of any chemical substances, leaving no residue behind when removed. Such gecko feet-mimicking adhesives have many applications in cutting-edge technologies such as bionics, soft robotic fingers, and body-tissue interfaces, as well as in more common commercial products like wall hangers, bandages, labels, tapes, or automobile trim components.

Researchers at the University of Florida have produced dry adhesive films that exhibit different adhesion forces and are reusable. Manipulating the size and number of microscale pores in shape memory polymer films can vary their adhesive strength when applied to a surface. The pores can open and close in response to multiple external stimuli, allowing removal and replacement of the adhesive films.

Application

Reusable dry adhesive films that can have multiple levels of adhesive force

Advantages

• Uses a microporous shape memory polymer, enabling different adhesive forces depending on the application
• Pores open and close when put in ethanol and water respectively, allowing reuse of the films
• Sticks to surfaces via dry adhesion, leaving no residue and facilitating easy placement and removal
• Adhesive film has a photonic structure, visually indicating adhesion state via color change

Technology

These microporous shape memory polymer films perform switchable dry adhesion. Microscale pores in the polymer create an adhesive force dependent on their number, size, and whether they are open or closed. Putting the films in water and drying them closes the pores while putting them in ethanol opens the pores. Closed pores lead to weaker adhesion, and open pores lead to stronger adhesion. Depending on the necessary adhesion force, manufacturers can manipulate the microporous dry adhesion films using plasma-etching or some other processes to vary the roughness of the film’s surface. The crystal structure of the SMP films couples film adhesiveness with color so that a color change signifies a change in adhesion state.

Instructional System Uses Multisensory Interface (touch, sight, sound) to Create Immersive Experience to Learn about Nanotechnology

This comprehensive video game-like program aids to promote fun and easy learning of science and math concepts in a classroom setting. Existing haptic technology is employed to enhance the training of pilots to fly aircraft, doctors to perform delicate and complex surgeries, and primarily for advanced scientific application including microscopy instrumentation and robotic manipulation. The efficacy of haptic technology is largely unexplored to the learning of science concepts. This is because the high cost of these applications has deemed haptics unmarketable for a mid to low-range price market. Researchers at the University of Florida have developed a program that combines an inexpensive haptic force feedback device, a virtual environment, and an auditory element to promote learning in the science, technology, engineering, and mathematics (STEM) fields. This technology may be broadly applied to younger audiences including, but not limited to, elementary and middle school students.

Application

Interactive, virtual learning material for the promotion of STEM topics in classroom settings.

Advantages

• Uses low cost feedback game controller, resulting in cost-effective instructional material
• Enables video game-like interface, making learning software easier to use for users of all ages
• Harnesses USB hook-up, allowing for cooperative and simple implementation with Windows-compatible computers.

Technology

This education program, HapNan, combines the low-cost Novint Falcon^® controller with easy-to-use instructional software to create an optimal tactile and visual learning environment. The Falcon controller incorporates three electrical motors connected to the controller's three extending arms. These arms are able to produce and carry a force of up to two pounds to the controller grip. The Falcon's handle reproduces realistic movement via the ability to move in all directions, in all three directional axes. When the 3D cursor controlled by the Falcon controller comes into contact with an object in the virtual environment, the computer updates the motors' currents accordingly to deliver an appropriate force to the device’s handle, where the user is able to feel. The computer updates the currents to the motors at a 1 kHz rate, or one thousand times per second, providing a very realistic sense of touch. The controller is connected to a computer system via USB port and is compatible with Windows operating systems.