Gerry Antony - Academia.edu (original) (raw)
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Papers by Gerry Antony
Polymers, 2017
During the past several years, we have been utilizing cyclodextrins (CDs) to nanostructure polyme... more During the past several years, we have been utilizing cyclodextrins (CDs) to nanostructure polymers into bulk samples whose chain organizations, properties, and behaviors are quite distinct from neat bulk samples obtained from their solutions and melts. We first form non-covalently bonded inclusion complexes (ICs) between CD hosts and guest polymers, where the guest chains are highly extended and separately occupy the narrow channels (~0.5–1.0 nm in diameter) formed by the columnar arrangement of CDs in the IC crystals. Careful removal of the host crystalline CD lattice from the polymer-CD-IC crystals leads to coalescence of the guest polymer chains into bulk samples, which we have repeatedly observed to behave distinctly from those produced from their solutions or melts. While amorphous polymers coalesced from their CD-ICs evidence significantly higher glass-transition temperatures, Tgs, polymers that crystallize generally show higher melting and crystallization temperatures (Tms, ...
Journal of Polymer Science Part B: Polymer Physics, 2013
Nanostructured amorphous bulk polymer samples were produced by processing them with small molecul... more Nanostructured amorphous bulk polymer samples were produced by processing them with small molecule hosts. Urea (U) and gamma-cyclodextrin (c-CD) were utilized to form crystalline inclusion compounds (ICs) with low and high molecular weight as-received (asr-) poly(vinyl acetate) (PVAc), poly (methyl methacrylate) (PMMA), and their blends as included guests. Upon careful removal of the host crystalline U and c-CD lattices, nanostructured coalesced (c-) bulk PVAc, PMMA, and PVAc/PMMA blend samples were obtained, and their glass-transition temperatures, T g s, measured. In addition, nonstoichiometric (n-s)-IC samples of each were formed with c-CD as the host. The T g s of the un-threaded, un-included portions of their chains were observed as a function of their degree of inclusion. In all the cases, these nanostructured PVAc and PMMA samples exhibited T g s elevated above those of their asreceived and solution-cast samples. Based on their comparison, several conclusions were reached concerning how their molecular weights, the organization of chains in their coalesced samples, and the degree of constraint experienced by un-included portions of their chains in (n-s)-c-CD-IC samples with different stoichiometries affect their chain mobilities and resultant T g s. V
... I would also like to thank Dr. Brad Busche and Jaewook Seok for their help with synthesis and... more ... I would also like to thank Dr. Brad Busche and Jaewook Seok for their help with synthesis and polymer blending. I would also like to thank Dr. Brandon Williamson for his help in making inclusion compounds and in analysis of results. Dr. Birgit Anderson, Judy Elson for ...
Polymers, 2017
During the past several years, we have been utilizing cyclodextrins (CDs) to nanostructure polyme... more During the past several years, we have been utilizing cyclodextrins (CDs) to nanostructure polymers into bulk samples whose chain organizations, properties, and behaviors are quite distinct from neat bulk samples obtained from their solutions and melts. We first form non-covalently bonded inclusion complexes (ICs) between CD hosts and guest polymers, where the guest chains are highly extended and separately occupy the narrow channels (~0.5–1.0 nm in diameter) formed by the columnar arrangement of CDs in the IC crystals. Careful removal of the host crystalline CD lattice from the polymer-CD-IC crystals leads to coalescence of the guest polymer chains into bulk samples, which we have repeatedly observed to behave distinctly from those produced from their solutions or melts. While amorphous polymers coalesced from their CD-ICs evidence significantly higher glass-transition temperatures, Tgs, polymers that crystallize generally show higher melting and crystallization temperatures (Tms, ...
Journal of Polymer Science Part B: Polymer Physics, 2013
Nanostructured amorphous bulk polymer samples were produced by processing them with small molecul... more Nanostructured amorphous bulk polymer samples were produced by processing them with small molecule hosts. Urea (U) and gamma-cyclodextrin (c-CD) were utilized to form crystalline inclusion compounds (ICs) with low and high molecular weight as-received (asr-) poly(vinyl acetate) (PVAc), poly (methyl methacrylate) (PMMA), and their blends as included guests. Upon careful removal of the host crystalline U and c-CD lattices, nanostructured coalesced (c-) bulk PVAc, PMMA, and PVAc/PMMA blend samples were obtained, and their glass-transition temperatures, T g s, measured. In addition, nonstoichiometric (n-s)-IC samples of each were formed with c-CD as the host. The T g s of the un-threaded, un-included portions of their chains were observed as a function of their degree of inclusion. In all the cases, these nanostructured PVAc and PMMA samples exhibited T g s elevated above those of their asreceived and solution-cast samples. Based on their comparison, several conclusions were reached concerning how their molecular weights, the organization of chains in their coalesced samples, and the degree of constraint experienced by un-included portions of their chains in (n-s)-c-CD-IC samples with different stoichiometries affect their chain mobilities and resultant T g s. V
... I would also like to thank Dr. Brad Busche and Jaewook Seok for their help with synthesis and... more ... I would also like to thank Dr. Brad Busche and Jaewook Seok for their help with synthesis and polymer blending. I would also like to thank Dr. Brandon Williamson for his help in making inclusion compounds and in analysis of results. Dr. Birgit Anderson, Judy Elson for ...