Dominic V Mcgrath
Publications
Abstract:
Electroactuated polymer (EAP) hydrogels based on JEFFAMINE® T-403 and ethylene glycol glycidyl ether (EGDGE) are used in an infusion pump based on the proprietary Pulse Actuated Cell System (PACS) architecture in development at Medipacs LLC. We report here significant progress in optimizing the formulation of the EAP hydrogels to dramatically increase hydrolytic stability and reproducibility of actuation response. By adjusting the mole fraction of reactive components of the formulation and substituting higher molecular weight monomers, we eliminated a large degree of the hydrolytic instability of the hydrogels, decreased the brittleness of the gel, and increased the equilibrium swelling ratio. The combination of these two modifications to the formulation resulted in hydrogels that exhibited reproducible swelling and deswelling in response to pH for a total period of 10-15 hours.
Abstract:
We present the preparation of a series of chiral dendrons, in which chiral subunits are placed in individual generational shells at increasing distances from the focal point, by a combination of convergent and divergent dendrimer synthesis methods. Analysis of chiroptical data suggests that these dendrons do not possess conformational order in solution.
Abstract:
Conditions for the self-metathesis assembly of dendrons with alkenyl focal points into dendrimers are developed. Assembly of more complex central cores is the subject of current efforts. Olefin metathesis has become a powerful method in organic synthesis. Several ruthenium-based alkylidiene complexes have led to considerable success in the ring-opening metathesis and ring-closing metathesis reactions in application to the total synthesis of natural products. A preliminary study on the use of metathesis to assemble benzyl aryl ether dendrimers is reported. Self-metathesis yielding dendrimers is observed and the effects of solvent, temperature and reaction conditions on final product yield is optimized.
Abstract:
The ring-opening metathesis polymerization (ROMP) of strained cyclic olefins is an important application of the olefin metathesis reaction. We have shown that the aqueous ROMP of exo-N-Methyl-7-oxabicyclo[2.2.1]hept-5-ene-2,3-dicarboximide yields a high molecular weight, thermally stable polymer with a low polydispersity in high yields under mild conditions. The mechanical properties and possible applications of these polymers are currently being investigated.