New types of nanoparticles, which display a large range of novel compositions and structures are now being generated at a distinctly rapid pace. These particles may have a wide variety of desirable properties, from novel electromagnetic behavior and mechanical reinforcement in soft materials, to flavor, fragrance and color in consumer goods and food. It remains, however, a critical challenge to establish a common method for incorporating this variety of nanoparticles into a range of materials. The encapsulation of nanoparticles into microcapsules -- which encompass a fluid-filled core and polymeric shell -- offers a key solution to this challenge; the microcapsules provide an effective means of regulating the release rate of the enclosed nanoparticles and targeting the delivery of the particles onto surfaces. The latter attribute is especially important for a number of applications. For example, for the nanoparticles to be effective in cosmetics and personal care products, they must reach the skin or hair; in a similar manner, for printing, textile and coating applications, the particles must be targeted to a substrate.
This Nanoscale Exploratory Research project is a proof-of-concept study in nanoscience, aimed at addressing the essential needs described above. The PIs will design fluid-driven microcapsules that carry nanoparticles to a desired surface, then release the particles to provide a coating on the underlying substrate. Such "road paving" systems not only play a valuable role in the applications noted above, but also form a useful tool for micro- and nanofabrication. They will also isolate conditions where nanoparticles released from the capsules can repair the damage in an underlying substrate, and thereby establish guidelines for designing nanoparticle-filled microcapsules that perform a "repair and go" function.
The project will integrate the different areas of expertise of the PIs. Balazs, the lead PI, will provide the theoretical basis to understand the dynamic behavior of nanoparticle-filled capsules, including their interactions with surfaces, and their release of nanoparticles. Emrick and Russell will provide synthesis and characterization, using amphiphilic graft copolymers as self-assembling encapsulants for nanoparticles such as quantum dots, and patterned substrates over which the capsules traverse and release their contents. By combining their efforts, the PIs plan to establish, within the one-year timeframe of the NER project, a new approach to microencapsulation and delivery of nanoparticles.
On a fundamental level, the results will have intellectual merit and scientific impact since the findings will provide insight into the dynamics of multiphase assemblies in fluid environments. These results will also yield new information on how to manipulate the inherent interactions within the system (e.g., the nanoparticle-capsule, the nanoparticle-surface, and the nanoparticle-fluid interactions) to yield the desired behavior.
Broad Impact
The findings will also have a broader impact; predicting how diverse particles can be delivered controllably to a substrate within a material will allow researchers to harness the unique functionalities offered by the nanoparticles in a range of applications and technologies, including the functionalities offered by the nanoparticles in a range of applications and technologies, including the personal care, pharmaceutical and food industries.
During the course of the funding period, the PIs will host a one-day symposium at the University of Massachusetts, on the topic of encapsulation and nanomaterials that are relevant to both commercial products and state-of-the-art research. The symposium, simply titled "Nanoencapsulation", will feature presentations by the PIs and other researchers from academia, as well as scientists working in corporations with products that hinge on encapsulation techniques. This meeting will have an educational impact on the students and researchers in the community and other attendees of the meeting.
The project will also have an educational benefit for the young researchers working on the project. In particular, it will allow the students working on the project (one at the University of Pittsburgh and one at UMass Amherst) to see first-hand the potential benefits of integrating theoretical and experimental research into a cohesive plan of action.
