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Moore, Jeffrey S. Moore, Jeffrey S. Braun, Paul V. Chen, Qian Evans, Christopher M. Tang, Shijia 2018-09-27T16:30:28Z 2018-09-27T16:30:28Z 2020-09-28T09:15:24Z 2018-07-13 2018-08 Transient polymers are emerging materials that transform from macromolecules to small molecules triggered by predefined environmental stimuli. Distinct from traditional degradable polymers, transient materials undergo domino like chain unzipping reactions, leading to controlled and complete depolymerization upon one cleavage. Taking advantage of the unique feature of triggered materials transience, this dissertation focuses on developing transient polymer microcapsules for programmable payload release. In Chapter 2, a rapid solvent evaporation strategy was developed to prepare transient polymer microcapsules with a low-ceiling-temperature polymer, cyclic poly(phthalaldehyde) (cPPA), as the shell wall materials. Chapter 3 described an ion co-activation effect that modulated cPPA depolymerization rates in the presence of acid. In Chapter 4, we further investigated the ion specificity in the co-activation effect and anion solvation properties were found to significantly impact the co-activation behavior. Based on the specific ion co-activation effect, we developed programmable microcapsules whose payload release kinetics depends on the ionic species in the solutions. Chapter 5 further expanded the co-activation effect in Lewis acid solutions that achieved depolymerization in mild environment. In Chapter 6, several studies were devoted to understand the molecular and interfacial mechanisms of the ion co-activation effect. Chapter 7 reviewed current topics on the Hofmeister effect and constructed a crude model on auto-catalytic microcapsules. The thesis research offers an encapsulation strategy and ion library for triggered release microcapsules and will be of significance for designing logic gate responsive microcapsules, reversible activation-deactivation materials and self-regulating reaction networks in autonomous chemical system. Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2020-08-01 The student, Shijia Tang, accepted the attached license on 2018-07-10 at 00:04. The student, Shijia Tang, submitted this Dissertation for approval on 2018-07-11 at 09:22. This Dissertation was approved for publication on 2018-07-13 at 09:41. DSpace SAF Submission Ingestion Package generated from Vireo submission #12789 on 2018-09-27 at 11:18:40 Made available in DSpace on 2018-09-27T16:30:28Z (GMT). No. of bitstreams: 5 TANG-DISSERTATION-2018.pdf: 12140673 bytes, checksum: 4f3f99535cc806cdd0763b05f5e400ff (MD5) LICENSE.txt: 4208 bytes, checksum: a701d587295790542884ebbbb1266843 (MD5) Permission for Figure 1.1.pdf: 113822 bytes, checksum: 3bd97dc13d14c2ff2f110df86dce2365 (MD5) Permission for Figure 1.4.pdf: 104752 bytes, checksum: a5295ef479d07240f75e892874d3600e (MD5) Permission form.docx: 1602282 bytes, checksum: c6a7fd2cd2db55434a55b8501641473e (MD5) Previous issue date: 2018-07-13 Embargo set by: Seth Robbins for item 107791 Lift date: 2020-09-27T16:30:34Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system Embargo set by: Seth Robbins for item 107791 Lift date: 2020-09-27T16:31:43Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system Embargo set by: Seth Robbins for item 107791 Lift date: 2020-09-27T16:34:29Z Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD system U of I Only Restriction Lifted for Item 107791 on 2020-09-28T09:15:24Z. application/pdf http://hdl.handle.net/2142/101693 en Copyright 2018 Shijia Tang Transient polymers, Triggered release, Hofmeister effect, Depolymerization kinetics Specific ion effects on transient polymers: a new strategy for programmable microcapusles text text Materials Science & Engineerng Materials Science & Engr University of Illinois at Urbana-Champaign Dissertation Ph.D.