ZACH HOLLINS, PhD
Thesis title:
"CAN GEL CONTENT IN EMULSION POLYMERIZATION BE OPTIMIZED? CONTRIBUTIONS OF BOTH CHEMISTRY AND PROCESS ON THE CROSSLINKING OF POLYME COLLOIDS"
Bio
NOW: Zach is currently at Global Regulatory Affairs: Chemistry, Manufacturing and Controls PhD Fellow at Vertex Pharmaceuticals in Boston, MA. As a member of the GRA CMC team, Zach supports new and existing drug substances and drug products by preparing and maintaining regulatory submission documentation needed to support ongoing clinical activities. To support ongoing clinical activities, Zach monitors new guidance documents for health authorities, communicates with stakeholders regarding process changes, and creates and monitors timelines for future submissions. To support CMC submissions to global health authorities, Zach works with cross-functional teams to ensure that drug substances and products are manufactured consistently, of high quality, and follow regulations.
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THEN: Zach grew up in Windham, NH and went to Merrimack College for B. Sci. in Biochemistry. There, he worked with Dr. Jimmy Franco (no, not the actor!) on the incorporation of an azobenzene derivative into nylon for the synthesis of a photoactive muscle mimic. Zach came to UNH in 2019 to pursue his Ph.D. and joined the Tsavalas group in 2020. In addition to his collection of yellow ducks, Zach kept us all organized in the lab and was our "go to" person for practically everything that the rest of us have forgotten. More importantly, Zach's research was focused on the fundamentals of emulsion polymerization and largely sponsored by the UNH Latex Morphology Industrial Consortium. Zach's projects centered around new mechanisms, kinetics, and rate constants associated the use of allyl methacrylate in emulsion polymerization as a crosslinker and he also developed a new class of reactive surfactants that we have coined "SurfXmers". Beyond these, Zach also contributed to our work in design of new cryoprotectants as well as to 3D printing and assembly of multi lobed paticles for the NH BioMade project.​
Project 1: Aqueous Phase Reactions With Allyl Methacrylate in Emulsion Polym'.
Allyl methacrylate (ALMA) is heavily used to prepare commercial polymeric materials. Unlike other commercially used crosslinkers, ALMA is an asymmetric di-reactive crosslinker that contains a methacrylic vinyl ester and an allyl terminal vinyl. Surprisingly, relatively few publications in the open literature explore the reaction mechanisms available to ALMA. ALMA shows great sensitivity to the reactions in the aqueous phase of emulsion polymerizations, as shown in both experimental and computational studies. As determined by quantum calculations, ALMA is 3.9 times more likely to undergo a radical addition reaction at the terminal vinyl when a persulfate radical is used and 1.5 times more likely to undergo a radical addition reaction at the terminal vinyl when a hydroxyl radical is used. These computational results align with the results obtained by varying the initiator and initiation temperature. Overall, ALMA is highly susceptible to aqueous phase chemistry, allowing it to enter the particle early in the reaction when compared to traditional routes, hence forming highly crosslinked networks
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See our publications below (coming soon!) for more detail
Project 2: blah blah blah - Coming Soon
This space will be used to describe Zach's second project.