BEGIN:VCALENDAR VERSION:2.0 PRODID:-//ZContent.net//ZapCalLib 1.0//EN CALSCALE:GREGORIAN METHOD:PUBLISH BEGIN:VEVENT SUMMARY:Synthesis and Characterization of Monocyclic Polymers LOCATION:Chemistry A101 TZID:America/Denver DTSTART:20220429T160000 UID:2026-05-07-23-41-04@natsci.colostate.edu DTSTAMP:20260507T234104 Description:About the Seminar:\n\nIn the modern world\, polymeric materials dominate both commercial and consumer materials. From car tires to drug d elivery capsules\, the applications of polymers are nearly limitless. As s uch\, there has been significant interest in understanding the structure-p roperty relationships for both theoretical and real polymers. In particula r\, the effect of chain ends on polymer structure and dynamics has receive d significant attention in an effort to access sophisticated nanostructure s with targeted properties.\nGiven that chain ends can also influence poly mer size and chain entanglement\, there is significant merit in understand ing polymers with and without chain ends.\n\nTraditionally\, the vast majo rity of non-tethered polymers contain two or more chain ends – these are classified as linear polymers. While linear polymer chains can possess mo re than two chain ends (star\, comb\, etc.)\, the absence of chain ends is impossible by definition. In contrast to linear polymers\, topological po lymers can have chains with zero (or more) chain ends. In the special case of a topological polymer possessing a ring architecture and zero chain en ds\, the polymer is termed a cyclic polymer. Due to their lack of chain en ds\, cyclic polymers have fundamentally different characteristics than the ir equivalent linear counterparts. These differences include chain dynamic s\, chain entanglement\, radius of gyration\, morphology\, viscosity and m ore. While cyclic polymers have been studied since the mid-1960s\, access to cyclic polymers with high purity and low dispersity has only been possi ble in recent years.\n\nIn this talk\, I will examine a journal article wh ich reports the synthesis and characterization of a conjugated cyclic poly mer\, cyclic polyacetylene (c-PA). Although polyacetylene has been previou sly shown to act as non-metallic semiconductor\, its extreme insolubility and air sensitivity has made characterization greatly challenging. The wor k discussed in this talk addresses this insolubility by creating a tempora rily soluble form of cyclic polyacetylene\, allowing for unprecedented cha racterization of a cyclic bottlebrush polyacetylene. Additionally\, while linear polyacetylene has been shown to strongly favor cis isomers\, the c- PA synthesized here was determined to possesses ~99% trans double bonds. F rom these results\, it is clear that cyclic polymers can possess very diff erent properties than their linear counterparts – providing further moti vation for continued research.\n\nLastly\, I will present preliminary resu lts from my own research on computational simulations of block copolymers via self-consistent field theory (SCFT). These computational simulations a llow one to calculate the approximate energy for a given polymer morpholog y from an initial guess for a unit cell. The process of obtaining these re sults will be discussed\, as well as the theoretical basis and shortcoming s of polymer self-consistent field theory.\n\nMiao\, Z.\; Gonsales\, S. A. \; Ehm\, C.\; Mentink-Vigier\, F.\; Bowers\, C. R.\; Sumerlin\, B. S.\; Ve ige\, A. S. Cyclic Polyacetylene. Nat. Chem. 2021\, 13 (8)\, 792–799. 4: 00 pm END:VEVENT END:VCALENDAR