Thin Film Thinner and More Conductive Films
Thin films are another way to apply our product (P3) to yours. Depending on the advantages you want, Applied Sciences produces high-quality uniform CNF-reinforced, polymer films custom for you. Our thin film materials are suitable for use as prepregging sheets or as fully-cured surface coating materials for EMI shielding.
Applied Sciences was awarded a Navy Phase II Small Business Innovative Research (SBIR) program grant to refine the production method for these products and produce pilot scale-sized thin films. This program builds on the success from a Navy Phase I SBIR where we demonstrated a new proprietary film production method.
Benefits of Thin-Film Technology
• Uniform conductivity
• Low filler content
• Thinner material with properties equivalent or better than legacy materials
• Ideal product for prepregging
• All the benefits of carbon nanofiber in a closed-form solution
Conductive Films and Inks
Conductive films and inks are widely used for electrostatic dissipation as well as EMI shielding in electronics, aircraft, and aerospace applications. These materials are typically fabricated using conductive materials such as carbon black and metal flakes.
But, carbon black requires high loadings in the resin film, and inks can negatively impact the durability of the films and coatings. The use of metal flakes in these applications also has limitations associated with high particle loadings required to reach resistivity targets. And the compatibility with the polymer matrices and corrosion are a current problem.
With the growth and large-scale production of carbon nanomaterials, it’s easier to use them in conductive films and inks. The high aspect ratio and high electrical conductivity of graphitic nanofibers and nanotubes makes it possible to achieve low electrical resistivity targets at very low filler loading.
Conductive Thin Polymer Films with Graphitic Nanomaterials Air Force Phase/STTP
Military air vehicle producers use thin, resistive films to enable cutting-edge performance to warfighters, but have been limited by performance and product uniformity, resulting in high scrap rates and parasitic mass. This can be eliminated through use of carbon nanomaterial enhanced thin films, which reduce weight and improve product uniformity by a factor of two. The advantages of carbon nanofibers were exploited in this project, and through the development of a new film fabrication process, advanced, isotropic thin polymer films were developed, which provide improved performance, quality, and a reduction in weight. Applied Sciences was awarded a STTP program for scaling-up the production process for conductive thin films with graphitic nanomaterials. Through this program, Applied Sciences is successfully transitioning the film fabrication process from a pilot-scale to a continuous large-scale production. Without this effort, a sole-source supplier will retain control over high prices and limit purchasing flexibility. Additionally, this class of nano-enhanced thin films shows the potential to provide game-changing performance for future air vehicles.
Film Properties Success During Navy Phase I Research
Through use of nano-scale reinforcements and their proper application, Applied Sciences capitalized on the promise of these materials during a Navy Phase I SBIR program to increase the performance of polymeric films which meet all of the Navy’s requirements at a lower thickness (and therefore less parasitic mass) than legacy materials. Applied Sciences will build on this success in the Phase II program by proving the capacity for commercial manufacture.
See what the Air Force had to say about the successful use of our thin films…
Significant progress was achieved in both the formulations of conductive solutions and the film production processing methods. Under this program, Applied Sciences identified an effective and synergistic combination of graphitic nanomaterials.
The blend of materials was found to balance conductivity and uniformity, while providing control of the percolation threshold and minimization of the loading of graphitic nano-scale additives. Both of the selected conductive additives and the selected polyimide resin are all commercially available in large volumes and at a low cost.
A readily scalable and effective dispersion protocol for preparing the film-forming conductive solutions was established and verified through dispersion analysis. Applied Science’s process is advantageous because scaling up production to larger area films only requires purchase and modification of appropriately sized commercially available equipment instead of designing and fabricating custom equipment.
While using the equipment assembled for the feasibility study in Phase I, it was determined preparation of robust, uniform films was quite rapid and reliable. The film materials developed by Applied Sciences are thinner (less parasitic mass) than the legacy material while meeting, or exceeding, all of the Phase I program goals, including weight reduction. These materials also met or exceeded the solvent resistance and bend testing requirements.
Thin Film Applications
Conductive thin films used in defense applications extend longevity and reduce weight. The same thin polymer films also have commercial electronics and commercial aircraft applications.