Technology Overview

Syzygy Memory Plastics maintains technology in shape memory polymers (SMPs), a unique manufacturing process, and flexible electronics. These technologies enable many applications that take advantage of body temperature to control shape and stiffness. Our core technology in SMPs are dynamic, smart materials that undergo a shape change above a tunable, critical temperature to a remembered shape. Flexible electronics enable applications, for example inside the human body, in which stiff, rigid silicon substrates cause harm. Improved adhesion and the ability to dynamically reposition and reshape sensors, antennas and recording devices in 3D enable new product paradigms to improve the quality of life. Patents have been filed in each of these technology areas to protect our intellectual property.  

Shape Memory Polymers

Shape memory polymers are a class of self-adjusting smart materials that are stiff like Plexiglas below a critical temperature (the glass transition temperature, T_g) and soft like rubber bands above T_g. Through manipulating polymer chemistry, we can adjust T_g very precisely (within a single degree) between sub-freezer temperatures and above boiling water temperatures. Two property changes are utilized by Syzygy: a greater than 1000 fold change in stiffness occurs over a roughly 30 °F temperature range around T_g; and a change in shape in response to a much smaller (less than 5 °F ) temperature change. The shape changing feature of these SMPs occurs after the materials have been heated, deformed and cooled below T_g to store a temporary shape. Then, when the material is reheated it remembers its original shape and returns to that shape in a process known as shape memory. We can control the force with which the SMP recovers in addition to controlling T_g.

Manufacturing Technology

Charles Goodyear invented a process in the 1840s called Vulcanization that uses sulfur to crosslink natural rubber to increase wear resistance and robustness. This process has enabled the creation and proliferation of the automobile tire industry and has aided in improving rubber products across industries. Syzygy’s patent-pending manufacturing technique, Mnemosynation™, enables the design of new polymers with improved mechanical properties at a reasonable cost. In the past, shape memory polymers with good memory properties have primarily been used in high cost, niche markets, such as biomedical implants, with high direct manufacturing costs and large development times. The costs involved in their manufacture (due to their inability to be melted and reshaped) have hindered their proliferation into mainstream consumer commodity products. Mnemosynation™ produces materials that can add significant value to various industries because they can be processed using traditional plastics processing techniques like injection molding, blow molding and extrusion. In addition, they have the properties of chemically crosslinked plastics and rubbers after they have been treated with ionizing radiation such as electron beams or gamma rays. Mnemosynation™ bestows enhanced memory properties on polymers and was named after the Greek goddess of memory, Mnemosyne, much like Vulcanization was named after the Roman god of fire. The Mnemosynation™ process was developed in tandem between Syzygy and Georgia Tech researchers and Syzygy owns the world-wide exclusive license to commercialize earpiece devices using this technology. Specifically, this patent-pending manufacturing technique enables three things independently: control of T_g (temperature at which the polymer earpiece softens); control of the rubbery modulus (E_R) (how much force the polymer exerts when it recovers or earplug comfort); and the ability to mass-produce devices at low costs by thermoplastic processing means, yet deliver thermoset properties (e.g. good memory characteristics, wear resistance, processability).

Flexible Electronics Technology

Current research in flexible electronics possesses a wide range of potential applications including flexible displays, radio frequency identification (RFID) tags, artificial skin, and biomedical devices. Devices for these and other applications may experience strains of 15% or more, which necessitates stretchable active components and interconnects. As a result, alternative materials and processing methods, such as the fabrication of semiconductors on polymer substrates, are in development. Most research conducted thus far with polymer substrates has used polyethylene naphthalate (PEN), polyimide, or polydimethylsiloxane (PDMS). Through collaboration with UT Dallas, we have shown preliminary success in fabricating electrodes on acrylate-based SMPs, which allow for increased control over substrate properties. Lithography is performed on a stiff (~1 GPa) shape memory polymer in its glassy state. When subsequently heated above its T_g, it softens to below 1 MPa to enable improved interface with bodily tissues.