Method Of Transferring Patterned Non-Densely Packed Interfacial Particle Films Onto Substrates,
2014
The University of Akron
Method Of Transferring Patterned Non-Densely Packed Interfacial Particle Films Onto Substrates, Li Jia, Matthew Ray
Li Jia
A process for transferring patterned non-densely packed interfacial particle films onto substrates by providing a substrate, modifying the substrate so that it is non-water wetting, providing an interfacial film of charged particles, applying a surface modifying procedure to said particles, and applying the interfacial particle film to the modified substrate to thereby form a patterned non-densely packed film on the substrate.
Submicron Surface Patterning Using Interfacial Colloidal Particle Self-Assembly,
2014
The University of Akron
Submicron Surface Patterning Using Interfacial Colloidal Particle Self-Assembly, Li Jia
Li Jia
No abstract provided.
The Effect Of The Core On The Thermotropic Behavior Of Three-Arm Star Poly [11-(4-Cyanophenyl-4-Phenoxy) Undecyl Acrylate] S Synthesized By Atom Transfer Radical Polymerization,
2014
The University of Akron
The Effect Of The Core On The Thermotropic Behavior Of Three-Arm Star Poly [11-(4-Cyanophenyl-4-Phenoxy) Undecyl Acrylate] S Synthesized By Atom Transfer Radical Polymerization, Coleen Pugh, Andrea Kasko, Steven Grunwald
Coleen Pugh
“Three-arm star” poly[11-(4′-cyanophenyl-4′′-phenoxy)undecyl acrylate]s were synthesized by atom transfer radical polymerization (ATRP) of 11-(4′-cyanophenyl-4′′-phenoxy)undecyl acrylate using two new trifunctional initiators: 1,3,5-tri- (methyl 2-bromopropionate)benzene and 2,4,6-tri[4′-methyl(2′′-bromopropionate)phenoxymethyl]mesitylene. The polymers synthesized with 1,3,5-tri(methyl 2-bromopropionate)benzene (series II) contained 14–127 repeat units according to gel permeation chromatography relative to linear polystyrene (GPCPSt) and 13–271 repeat units according to GPC with a light scattering detector (GPCLS). Those synthesized with 2,4,6-tri[4′-methyl(2′′-bromopropionate)phenoxymethyl]mesitylene (series III) contained 14–87 repeat units according to GPCPSt and 10–120 repeat units according to GPCLS. The absolute molecular weight, size, and shape of both series of polymers were characterized by light scattering in CH2Cl2, and …
Development Of A Colloidal Lithography Method For Patterning Nonplanar Surfaces,
2014
The University Of Akron
Development Of A Colloidal Lithography Method For Patterning Nonplanar Surfaces, Sarang Bhawalkar, Jun Qing, Michael Heiber, Li Jia
Li Jia
A colloidal lithography method has been developed for patterning nonplanar surfaces. Hexagonal noncontiguously packed (HNCP) colloidal particles 127 nm−2.7 μm in diameter were first formed at the air−water interface and then adsorbed onto a substrate coated with a layer of polymer adhesive 17 nm thick. The adhesive layer plays the critical role of securing the order of the particles against the destructive lateral capillary force generated by a thin film of water after the initial transfer of the particles from the air−water interface. The soft lithography method is robust and very simple to carry out. It is applicable to a …
Characterization Of Linear And Branched Polyacrylates By Tandem Mass Spectrometry,
2014
The University Of Akron
Characterization Of Linear And Branched Polyacrylates By Tandem Mass Spectrometry, Kittisak Chaicharoen, Michael Polce, Anirudha Singh, Coleen Pugh, Chrys Wesdemiotis
Coleen Pugh
The unimolecular degradation of alkali-metal cationized polyacrylates with the repeat unit CH(2)CH(COOR) and a variety of ester pendants has been examined by tandem mass spectrometry. The fragmentation patterns resulting from collisionally activated dissociation depend sensitively on the size of the ester alkyl substituent (R). With small alkyl groups, as in poly(methyl acrylate), lithiated or sodiated oligomers (M) decompose via free-radical chemistry, initiated by random homolytic C-C bond cleavages along the polymer chain. The radical ions formed this way dissociate further by backbiting rearrangements and beta scissions to yield a distribution of terminal fragments with one of the original end groups …
N-Type Conjugated Polymers Containing Diborylene Units, Methods Of Making, And A Device Comprising The Compound,
2014
The University of Akron
N-Type Conjugated Polymers Containing Diborylene Units, Methods Of Making, And A Device Comprising The Compound, Li Jia
Li Jia
N-type conjugated compounds are disclosed which include at least one conjugated electron-acceptor unit The conjugated electron-acceptor unit includes a diborylene unit The compounds find application in an electron acceptor layer of an electronic device.
Synthesis, Isolation, And Thermal Behavior Of Polybutadiene Grafted With Poly (2, 3, 4, 5, 6-Pentafluorostyrene),
2014
The University Of Akron
Synthesis, Isolation, And Thermal Behavior Of Polybutadiene Grafted With Poly (2, 3, 4, 5, 6-Pentafluorostyrene), Marta Paz-Pazos, Coleen Pugh
Coleen Pugh
2,3,4,5,6-Pentafluorostyrene (PFS) was copolymerized with polybutadiene (PB) in tetrahydrofuran using benzoyl peroxide as the initiator at 50, 60, and 80 °C. The copolymerizations follow typical radical polymerization kinetics and behavior. The grafting parameters were evaluated as a function of monomer conversion, initiator concentration, and/or temperature by gel permeation chromatography of directly injected copolymerization mixtures. The grafting efficiencies and grafting ratios are most consistent with a system that terminates by combination and whose graft sites are generated by hydrogen abstraction of allylic radicals by primary initiator radicals. Pure graft copolymers were isolated by extracting unreacted PB into hexanes and PPFS homopolymer …
Regioregular Poly(3-Alkanoylthiophene): Synthesis And Electrochemical, Photophysical, Charge Transport, And Photovoltaic Properties,
2014
The University Of Akron
Regioregular Poly(3-Alkanoylthiophene): Synthesis And Electrochemical, Photophysical, Charge Transport, And Photovoltaic Properties, Chao Wang, Felix Kim, Guoqiang Ren, Yongqian Xu, Yi Pang, Samson Jenekhe, Li Jia
Li Jia
Head-to-tail regioregular poly(3-heptanoylthiophene) (PHOT) was synthesized by Ni-catalyzed polycondensation of the 2,2-dimethyl-1,3-propanediol-protected Grignard monomer followed by deprotection. Cyclic voltammetric (CV) study demonstrates that the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) of PHOT are 0.5 eV lower in energy than those of the head-to-tail poly(3-hexylthiophene) (HT-P3HT). Their optical band gaps are essentially the same. Incomplete photoluminescence (PL) quenching was observed in thin films of the 1:1 blend of PHOT and HT-P3HT. PHOT displayed a glass transition at ∼269 °C and decomposed at ∼300 °C according to differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Wide-angle X-ray …
Homopolyrotaxanes And Homopolyrotaxane Networks Of Peo,
2014
The University of Akron
Homopolyrotaxanes And Homopolyrotaxane Networks Of Peo, Coleen Pugh
Coleen Pugh
No abstract provided.
Measurement Of Chain Transfer Constants To Polymer Using Oligomers And Model Compounds: Chain Transfer To Poly [11-(4'-Cyanophenyl-4''-Phenoxy) Undecyl Acrylate] In Radical Polymerization,
2014
The University of Akron
Measurement Of Chain Transfer Constants To Polymer Using Oligomers And Model Compounds: Chain Transfer To Poly [11-(4'-Cyanophenyl-4''-Phenoxy) Undecyl Acrylate] In Radical Polymerization, Coleen Pugh, Guangyu Fan, Andrea Kasko
Coleen Pugh
The chain transfer constant to polymer (CP) for poly[11-(4‘-cyanophenyl-4‘ ‘-phenoxy)undecyl acrylate] was measured directly by the Mayo method by following the decrease in molecular weight at low monomer conversion by gel permeation chromatography of poly(methyl acrylate) generated in the presence of increasing amounts of 11-(4‘-cyanophenyl-4‘ ‘-phenoxy)undecyl propionate (CP = (6.62 ± 0.476) × 10-3) and 11-(4‘-cyanophenyl-4‘ ‘-phenoxy)undecyl isobutyrate (CP = (4.27 ± 0.858) × 10-3) as model compounds that mimic one repeat unit of the polymer and oligo[11-(4‘-cyanophenyl-4‘ ‘-phenoxy)undecyl acrylate] with nine repeat units (CP = (5.54 ± 0.608) × 10-3) synthesized by atom transfer radical polymerization. The mean chain …
The Role Of Phosphine In Cobalt-Catalyzed Carbonylative Polymerization Of N-Alkylaziridines,
2014
The University of Akron
The Role Of Phosphine In Cobalt-Catalyzed Carbonylative Polymerization Of N-Alkylaziridines, Li Jia
Li Jia
A series of CH3COCo(CO)3L complexes (1, L = PCy3; 2, L = PMe2Ph; 3, L = PPh3; 4, L = P(para-F-Ph)3; 5, L = P(meta-F-Ph)3; and 6, L = P(ortho-tolyl)3) were studied as precatalyst for the title polymerization. The Co–P bond length primarily responds to the cone angle of the phosphine ligand (6 > 1 > 2 ≈ 3 ≈ 4 ≈ 5), while the back-donation to the axial acetyl ligand and the equatorial CO ligand depends on the electron-donating ability of the phosphine and increases in the order 1 > 6 > 2 > 3 > 4 > 5. The equilibrium constant for CH3COCo(CO)3L + CO …
Design And Regioselective Synthesis Of (2-Bromo-2-Alkoxycarbonyl) Ethyl Acrylates As Inimers For Hyperbranched (Co) Polyacrylates,
2014
The University of Akron
Design And Regioselective Synthesis Of (2-Bromo-2-Alkoxycarbonyl) Ethyl Acrylates As Inimers For Hyperbranched (Co) Polyacrylates, Coleen Pugh, Bindu Raveendra, Anirudha Singh, Reichel Samuel, Guillermina Garcia, Maurice Morton
Coleen Pugh
A route based on deaminohalogenation of serine is established to synthesize bromoinimers that can be homopolymerized to produce hyperbranched polyacrylates that are true architectural analogues of linear polyacrylates; that is, an ester group is attached to every other carbon along the polymer backbone, and each repeat unit contains a free ester side chain.
Antifouling Poly(B-Peptoid)S,
2014
The University Of Akron
Antifouling Poly(B-Peptoid)S, Shaohui Lin, Bo Zhang, Michael Skoumal, Brian Ramunno, Xiaopeng Li, Chrys Wesdemiotis, Lingyun Liu, Li Jia
Li Jia
A new type of polymer highly resistant to nonspecific protein adsorption is reported. Poly(N-methyl-β-alanine) (PMeA) and poly(N-ethyl-β-alanine) (PEtA) synthesized via cobalt-catalyzed carbonylative polymerization of N-methylaziridine and N-ethylaziridine were end-functionalized with thiol groups and grafted onto Au surfaces. Protein adsorption was studied by the surface plasmon resonance (SPR) method. The amounts of representative single proteins adsorbed onto the PMeA- and PEtA-grafted surfaces were below the detection limit of SPR at the pg/mm(2) level. After exposure to full blood plasma and serum for 10 min, protein adsorption was at the level of ∼ 100 pg/mm(2), similar to the level of protein adsorption …
Synthesis And Electrochemical Properties Of A New Class Of Boron-Containing N-Type Conjugated Polymers,
2014
The University Of Akron
Synthesis And Electrochemical Properties Of A New Class Of Boron-Containing N-Type Conjugated Polymers, Jianfang Chai, Chao Wang, Li Jia, Yi Pang, Matthew Graham, Stephen Cheng
Li Jia
Several electron-deficient polymers containing the 9,10-diboroanthracene unit have been synthesized and characterized. Electrochemical study shows that they have high electron affinities. Photoluminescence of rr-P3HT is quenched in the presence of one of the polymers in the solid state, demonstrating the potential utility of this class of polymer as powerful n-type materials in organic photovoltaic devices.
Synthesis Of Hyperbranched Polyacrylates By A Chloroinimer Approach,
2014
The University of Akron
Synthesis Of Hyperbranched Polyacrylates By A Chloroinimer Approach, Coleen Pugh, Anirudha Singh, Reichel Samuel, Karla Bernal Ramos
Coleen Pugh
(2-Chloro-2-alkoxycarbonyl)ethyl acrylates with methyl, dodecyl, perfluoroalkyl, siloxane, oligooxyethylene, and mesogenic ester substituents were synthesized as inimers for self-condensing vinyl polymerization (SCVP) to produce hyperbranched polyacrylates. The inimers were polymerized by atom transfer radical polymerization under a variety of conditions to produce soluble polymers with broad polydispersities (up to PDI = 5.24) characteristic of hyperbranched polymers, although the isolated polymers had narrower polydispersities. The molecular weight distribution was followed as a function of time and inimer conversion for the polymerization of the mesogenic inimer. The first-order inimer conversion was linear with time. The buildup of a hyperbranched structure during the SCVP …
Synthesis And Mass Spectrometry Studies Of An Amphiphilic Polyether-Based Rotaxane That Lacks An Enthalpic Driving Force For Threading,
2014
The University Of Akron
Synthesis And Mass Spectrometry Studies Of An Amphiphilic Polyether-Based Rotaxane That Lacks An Enthalpic Driving Force For Threading, Kathleen Wollyung, Kaitian Xu, Michael Cochran, Andrea Kasko, Wayne Mattice, Chrys Wesdemiotis, Coleen Pugh
Coleen Pugh
A pure amphiphilic macrocrown ether (MC-12) was obtained by removing linear oligomers and larger macrocycles at the macrocyclization step, before proceeding with an established synthetic procedure. This pure MC-12 was used to synthesize a rotaxane composed of one MC-12 ring threaded with one end-capped poly(tetrahydrofuran) (PTHF) oligomer by equilibrating half an equivalent of the thread with an organized solution of MC-12 and end-capping the threads with excess 2-p-[tris(p-tert-butylphenyl)methyl]phenoxymethyl-4,4-dimethylazlactone. The rotaxane was positively identified by matrix-assisted laser desorption/ionization time-of-flight (MALDI-ToF) mass spectrometry (MS), although the spectra showed a low abundance of the rotaxane ions and high abundances of unthreaded MC-12 and …
Cobalt-Catalyzed Carbonylative Polymerization Of Azetidines,
2014
The University Of Akron
Cobalt-Catalyzed Carbonylative Polymerization Of Azetidines, Jianfang Chai, Guosheng Liu, Kittisak Chaicharoen, Chrys Wesdemiotis, Li Jia
Li Jia
We provide a full account on our study of the cobalt-catalyzed carbonylative polymerization of N-alkylazetidines involving three representative monomers. The individual N-alkylazetidine monomers display different characteristics in the polymerization, allowing the incorporation of amine and ester units into the amide-based polymers. We will first present the synthesis and characterization of poly(amide-co-amine) with a gradient amine distribution. Then, we will describe how to control the ester distribution in poly(amide-co-ester)s. Poly(amide-co-ester)s containing multiple segments, within which the ester units distribute in a gradient fashion, will be compared with multiblock poly(amide-co-ester)s. Finally, we report our discovery of a novel chain transfer pathway via …
Architectural Effects In Side-Chain Liquid Crystalline Polymers: Hyperbranched Sclcps,
2014
The University of Akron
Architectural Effects In Side-Chain Liquid Crystalline Polymers: Hyperbranched Sclcps, Coleen Pugh, Anirudha Singh
Coleen Pugh
No abstract provided.
Novel Use Of Polymer Brush In Colloidal Lithography To Overcome Lateral Capillary Force,
2014
The University of Akron
Novel Use Of Polymer Brush In Colloidal Lithography To Overcome Lateral Capillary Force, Jun Qian, Sarang Bhawalkar, Yongshen Xu, Li Jia
Li Jia
A general method has been developed for transferring interfacially trapped, submonolayer hexagonal arrays of silica particles for nano- and mesoscopic surface patterning. Poly(n-butyl acrylate) and poly(n-butyl acrylate-random-N,N-diethylaminoethyl acrylate) brushes were grafted on the substrates via the "graft-from" method using atom transfer radical polymerization. The polymer brush served as an adhesive promoter between the particles and the substrate and proved to be effective for locking the particles in the hexagonal lattice against the lateral capillary force arising from a thin layer of water attached to the surface of the substrate. Several parameters that influence preservation of the order of the particle …
Elucidating The Structure Of Hyperbranched Side-Chain Liquid Crystalline Polyacrylates,
2014
The University Of Akron
Elucidating The Structure Of Hyperbranched Side-Chain Liquid Crystalline Polyacrylates, Anirudha Singh, Coleen Pugh
Coleen Pugh
Side-chain liquid crystalline polymers (SCLCPs) prepared by non-living polymerizations generally exhibit very broad phase transitions, in contrast to low molar mass liquid crystals. The broad phase transitions were immediately dismissed in the SCLCP literature as being due to polydispersity in molecular weight. For example, when poly[11-(4'-cyanophenyl-4"-phenoxy)undecyl acrylate] was prepared by a conventional radical polymerization and then fractionated,1 each of the fractions underwent a narrower smectic A to isotropic transition (full widths at half maximum peak intensity (fwhm) = 6.25 – 10.71 o C) than the unfractionated polymer (fwhm = 17.0 o C).2 However, we have provided evidence that the broad …
