New Polymeric Materials
Several members of the Moore group are working on projects related to development of novel polymeric materials to meet the challenges of today`s world. We are specifically interested in generation of polymers for applications ranging from compartmentalization and on-demand release of actives, smart packaging of transient electronics to functional membranes for water purification.
Metastable Packaging for Transient Electronic Devices
This project investigates methods and materials for to create transient electronics packaging. Our targets have the ability protect sensitive electronics from the environment and possess the ability to disappear in controlled ways at a specific time. We are developing a library of metastable polymers and exploring new triggering modes and concepts that activate rapid transience (< 5 minutes) for packaging microelectronic devices. The long-term goal is to develop depackaging cascades for time programmable disintegration and flash-triggering where the initial activation signal is amplified and propagated until complete device degradation.
Compartmentalization and On-demand Release
Compartmentalization is a powerful concept in biology that enables organisms to isolate and carry out multiple functions in an interdependent fashion. The growing needs of isolation and targeted delivery of actives require development of next generation synthetic compartmentalized systems. To meet these needs, our group pursues the synthesis and development of new stimuli-responsive polymeric materials that can rapidly and irreversibly depolymerize on triggering. Such criteria can be met via the development of polymers that are thermodynamically unstable at room temperature, yet kinetically stabilized from depolymerization. We are currently exploring a variety of new depolymerizable polymer architectures, while also exploiting the use of known polymers that possess such qualities in pursuit of applications such as packaging of transient electronics, disappearing materials, shell-walls for triggerable microcapsules, and polymeric materials capable of remodeling or shape-changing phenomena.
Efficient encapsulation of active cargo is another interest of our research. Emulsion templated encapsulation relies on a discrete control of the emulsifier, as well as the continuous and discontinuous phases. Unlike conventional oil-in water emulsions, the encapsulation of hydrophilic actives via water-in-oil emulsions, i.e. inverse emulsion, is far less studied. We pursue the basic understanding of how a metastable emulsion is formed and further locked down via interfacial polymerization with different techniques including microfluidics. From this standing point, we expect applications in encapsulation of curing agents and on-demand release.
Functional Membranes for Water Purification
Finding ways to efficiently purify toxins from water is rapidly becoming a global issue as the world's supply of drinking water steadily decreases. The purpose of this project is to improve the filtration properties of existing water filtration membranes to remove various contaminants (organics, arsenates, etc.) through covalent modification without adversely affecting the physical properties of the film, such as water flux. Two areas of modification are currently being investigated; the covalent attachment of transport modifiers to the polyamide active layer and direct modification of the support. We have found that rejection of an organic surrogate and various salts is enhanced without any long-term loss of efficiency and without significant increase in the water flux of the membrane.
Here the concepts of catalysis and initiation are applied to a pair of polymer interfaces. Our idea for a "touch-and-go" (TAG) reaction is that two components of a catalyst are grafted to different surfaces; when the surfaces come into contact or "touch," catalyst formation proceeds, causing the reaction to proceed or "go." Thus, a molecular reaction would be controlled by the spatial proximity of macroscopic or microscopic objects. Our goals include proving the feasibility of a TAG reaction and quantifying the parameters that influence rates. Once the feasibility of the TAG reaction has been shown, we will explore various reactions, surface topographies and applications.
- Robertson, I.D.; Pruitt, E.L.; Moore, J.S. "Frontal Ring-Opening Metathesis Polymerization of Exo-Dicyclopentadiene for Low Catalyst Loadings", ACS Macro Lett., 2016, 5, 593-596. DOI: 10.1021/acsmacrolett.6b00227
- Lee, O.P.; Lopez-Hernandez, H.; Moore, J.S. Tunable Thermal Degradation of Poly(vinyl butyl carbonate sulfone)s via Side-Chain Branching, ACS Macro Lett., 2015, 4, 665-668. DOI: 10.1021/acsmacrolett.5b00234
- Song, Y.; Cheng, P.-N.; Zhu, L.: Moore, E.G.; Moore, J.S. "Multivalent Macromolecules Redirect Nucleation-Dependent Fibrillar Assembly into Discrete Nanostructures", J. Am. Chem. Soc., 2014, 136, 5233-5236. DOI:10.1021/ja501102f
- Kaitz, J.A.; Diesendruck, C.E.; Moore, J.S. End Group Characterization of Poly(phthalaldehyde): Surprising Discovery of a Reversible, Cationic Macrocyclization Mechanism. JACS, 2013, 135, 12755-12761. DOI: 10.1021/ja405628g