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Farewell lunch for Damien and Jeehye, 17 Aug, 2016 @ Vesta
ONE LAB had a farewell party for Damien and Jeehye at Vesta!
Wish all the best for Damien and Jeehye :)
Commencement, Feb 19, 2016 @ KAIST
Hayeon and Song finally got MS degree!
ONE LAB congratulated them on having done an excellent job :)
Group photo, 2 Nov. 2015
(back) Nesibe, Hong, Song, Saravanan, Cafer, Damien, Jason
(front) Mi-Young, Hayeon, Dong Ah, Jeehye, Vepa
Hanim's visit from ICL
ONE lab has welcomed Hanim from Imperial College London for Summer Research Program!
Group photos, Jan 11 2015 @5th KCCS Jeju conference
Hong, Jeehye, Saravanan, Cafer, Song, Hayeon, Nesibe
Synthesis of a nanoporous 1,2,4-oxadiazole network with high CO2 capture capacity
D. Ko, H. A. Patel, C. T. Yavuz*
Chem. Commun., 51, 2915-2917 (2015). [DOI]
Chem. Commun., 51, 2915-2917 (2015). [DOI]
Developing an adsorbent to mitigate carbon dioxide without large energy penalty is highly desired. Here, we present a silylation synthetic route to form a processable and otherwise impossible porous 1,2,4-oxadiazole network, which achieves 2 mmol/g of CO2 capacity owing to nitrogen-rich structure. This network shows high CO2/N2-selectivity, thermal stability up to 450 oC, and low-heat of adsorption (26.4 kJ/mol), facilitating easy regeneration.
Mr. Joosung Jason Lee
MS Student
January 2015 - present
Education:
BS University of Toronto, Toronto, Canada
Email: wynter@kaist.ac.kr
January 2015 - present
Education:
BS University of Toronto, Toronto, Canada
Email: wynter@kaist.ac.kr
Magnetic BaFe12O19 nanofiber filter for effective separation of Fe3O4 nanoparticles and removal of arsenic
J. Byun, H. A. Patel, C. T. Yavuz*
J. Nanopart. Res., 16:2787 (2014). [DOI]
J. Nanopart. Res., 16:2787 (2014). [DOI]
Magnetic nanoparticles are promising in applications where magnetic separation is intended, although material losses via leaching mechanisms are often inevitable. Magnetic separations with widely available permanent magnets can effectively trap particles, leading to a complete removal of used or waste particles. In this report, we first demonstrate the synthesis of the thinnest (112.7 ± 16.4 nm) and most magnetic (71.96 emu g−1) barium hexaferrite (BaFe12O19, BHF—fridge magnet) via an organic solvent-free electrospinning procedure. When the fibers are then packed into a column, they clearly remove 12 nm magnetite (Fe3O4) nanoparticles quantitatively. The same BHF cartridge also removes more than 99.9 % As-treated magnetite nanoparticles at capacities up to 70 times of its weight. As a result, one liter of 150 μg L−1 As-contaminated water can be purified rapidly at a material cost of less than 2 US cents.
Dr. Saravanan Subramanian
Postdoctoral Scholar
November 2014 - present
Education:
PhD Central Salt and Marine Chemicals Research Institute (CSIR), Bhavnagar, Gujarat, India
MS Sri Paramakalyani College, M S University, Tirunelveli, Tamilnadu, India
BS The M. D. T. Hindu College, M S University, Tirunelveli, Tamilnadu, India.
Email: saravanans@kaist.ac.kr
Publications:
1. M. Nazish, S. Saravanan, Noor-ul H. Khan, Rukhsana I. Kureshy, Sayed H. R. Abdi,
and Hari C. Bajaj. Magnetic Fe3O4 nanoparticle supported phosphotungstic acid as a
recyclable catalyst for Kabachnik-Fields reaction of isatins, imines and aldehydes under
solvent free condition, Accepted in ChemPlusChem. 2014.
2. Debashis Ghosh, S. Saravanan, Sayed H. R. Abdi, Noor-ul H. Khan, Rukhsana I.
Kureshy and Hari C. Bajaj, Phosphotungstic Acid Catalyzed Allylation of Isatins and NBoc
Amido sulfones Under Solvent Free Condition. Accepted in Asian J. Org. Chem.
2014.
3. Pramod kumar, S. Saravanan, Noor-ul Hasan Khan, Firasat Hussain, Surendra Singh.
Chiral Mn(III) Salalen and Salan Complexes derived from Pyrrolidin-2-ylmethanamine
and Catalytic Activity in Asymmetric Strecker Reaction, Accepted in Eur. J. Inorg.
Chem. 2014. [DOI: 10.1002/ejic.201402548]
4. Ajay Jakhar, Arghya Sadhukhan, Noor-ul H. Khan, S. Saravanan, Rukhsana I. Kureshy,
Sayed H. R. Abdi, Hari C. Bajaj. Asymmetric hydrocyanation of nitro olefins catalyzed
by Al(III) salen complex. Accepted in Chemcatchem 2014. [DOI:
10.1002/cctc.201402373]
5. Nabin Ch. Maity, Prasanta Kumar Bera, S. Saravanan, Sayed H. R. Abdi, Rukhsana I.
Kureshy, Noor-ul H. Khan, Hari C. Bajaj. Diethyl tartrate linked chiral macrocyclic
Mn(III) salen complex: as recyclable catalyst for enantioselective epoxidation of nonfunctionalized
alkenes and oxidative kinetic resolution of racemic secondary alcohols.
Accepted in Chempluschem 2014 [DOI: 10.1002/cplu.201402131]
6. Manish Kumar, S. Saravanan, Noor-ul H. Khan, Rukhsana I. Kureshy, Sayed H. R.
Abdi, and Hari C. Bajaj. Unravelling a new class of Chiral Organo-catalyst for
Asymmetric Ring Opening Reaction of Meso Epoxides with Anilines. Org. Lett. 2014,
16 (11), 2798–2801.
7. S. Saravanan, Noor-ul H. Khan, Rukhsana I. Kureshy, Sayed H. R. Abdi, and Hari C.
Bajaj, Small Molecule as a Chiral Organocatalyst for Asymmetric Strecker Reaction: An
Effective Protocol for the Synthesis of Chiral Hydantoin. ACS Catalysis, 2013, 3 (12),
2873–2880.
8. S. Saravanan, Noor-ul H. Khan, Prasanta K. Bera, Rukhsana I. Kureshy, Sayed H. R.
Abdi, Prathibha Kumari, Hari C. Bajaj, Catalysis of Enantioselective Strecker Reaction in
the Synthesis of D-Homophenylalanine Using Recyclable, Chiral, Macrocyclic Mn(III)–
Salen Complexes. Chemcatchem, 2013, 5, 1374.
9. Debashis Ghosh, Debashis Sahu, S. Saravanan, Sayed H. R. Abdi, Bishwajit Ganguly,
Noor-ul H. Khan, Rukhsana I. Kureshy and Hari C. Bajaj, Synthetically amenable amide
derivatives of tosylated-amino acids as organocatalysts for enantioselective allylation of
aldehydes: computational rationale for enantioselectivity. Org. Biomol. Chem., 2013, 11,
3451-3460.
10. S. Saravanan, Arghya Sadhukhan, Noor-ul H. Khan, Rukhsana I. Kureshy, Sayed H. R.
Abdi, and Hari C. Bajaj, C2-Symmetric Recyclable Organocatalyst for Enantioselective
Strecker Reaction for the Synthesis of α-Amino Acid and Chiral Diamine- an
Intermediate for APN Inhibitor, J. Org. Chem. 2012, 77, 4375−4384.
11. Arghya Sadhukhan, S. Saravanan, Noor-ul H. Khan, Rukhsana I. Kureshy, Sayed H. R.
Abdi, and Hari C. Bajaj, Modified Asymmetric Strecker Reaction of Aldehyde with
Secondary Amine: A Protocol for the Synthesis of S‑Clopidogrel (An Antiplatelet
Agent), J. Org. Chem. 2012, 77, 7076−7080.
12. Arpan K. Shah, Noor-ul H. Khan, Govind Sethia, S. Saravanan, Rukhsana I. Kureshy,
Sayed H. R. Abdi, Hari C. Bajaj, Tin exchanged zeolite as catalyst for direct synthesis of
α-amino nitriles under solvent-free conditions, Appl. Catal., A, 2012, 419– 420, 22–30.
13. Noor-ul H. Khan, Arghya Sadhukhan, Nabin C. Maity, Rukhsana I. Kureshy, Sayed H.R.
Abdi, S. Saravanan, Hari C. Bajaj, Enantioselective Oacetylcyanation/
cyanoformylation of aldehydes using catalysts with built-in crown etherlike
motif in chiral macrocyclic V(V) salen complexes, Tetrahedron, 2011, 67, 7073-
7080.
14. S. Saravanan, Rukhsana I. Kureshy, Sayed H. R. Abdi, Hari C. Bajaj, Mn(III) salen
complexes-catalyzed enantioselective addition of trimethylsilylcyanide to Nbenzylimines
in the presence of 4-phenyl pyridine-N-oxide as an additive, Noor-ul H.
Khan, Tetrahedron: Asymmetry 2010, 21, 2076–2080.
15. Noor-ul H. Khan, S. Saravanan, Rukhsana I. Kureshy, Sayed H.R. Abdi, Arghya
Sadhukhan, Hari C. Bajaj, Asymmetric addition of trimethylsilylcyanide to Nbenzylimines
catalyzed by recyclable chiral dimeric V(V) salen complex, J. Organomet.
Chem. 2010, 695, 1133–1137.
16. Rukhsana I. Kureshy, Santosh Agrawal, S. Saravanan, Noor-ul H. Khan, Arpan K. Shah,
Sayed H. R. Abdi , Hari C. Bajaj, E. Suresh, Direct Mannich reaction mediated by
Fe(Cp)2PF6 under solvent-free conditions, Tetrahedron Lett. 2010, 51, 489–494.
17. S. Saravanan, Noor-ul H. Khan, Rukhsana I. Kureshy, Sayed H. R. Abdi, and Hari C.
Bajaj. An efficient and recyclable chiral V(V) dinuclear catalyst for enantioselective
Strecker reaction: A comparative and mechanistic studies for the reactivity of organic and
alkali cyanide sources. (Communicated)
November 2014 - present
Education:
PhD Central Salt and Marine Chemicals Research Institute (CSIR), Bhavnagar, Gujarat, India
MS Sri Paramakalyani College, M S University, Tirunelveli, Tamilnadu, India
BS The M. D. T. Hindu College, M S University, Tirunelveli, Tamilnadu, India.
Email: saravanans@kaist.ac.kr
Publications:
1. M. Nazish, S. Saravanan, Noor-ul H. Khan, Rukhsana I. Kureshy, Sayed H. R. Abdi,
and Hari C. Bajaj. Magnetic Fe3O4 nanoparticle supported phosphotungstic acid as a
recyclable catalyst for Kabachnik-Fields reaction of isatins, imines and aldehydes under
solvent free condition, Accepted in ChemPlusChem. 2014.
2. Debashis Ghosh, S. Saravanan, Sayed H. R. Abdi, Noor-ul H. Khan, Rukhsana I.
Kureshy and Hari C. Bajaj, Phosphotungstic Acid Catalyzed Allylation of Isatins and NBoc
Amido sulfones Under Solvent Free Condition. Accepted in Asian J. Org. Chem.
2014.
3. Pramod kumar, S. Saravanan, Noor-ul Hasan Khan, Firasat Hussain, Surendra Singh.
Chiral Mn(III) Salalen and Salan Complexes derived from Pyrrolidin-2-ylmethanamine
and Catalytic Activity in Asymmetric Strecker Reaction, Accepted in Eur. J. Inorg.
Chem. 2014. [DOI: 10.1002/ejic.201402548]
4. Ajay Jakhar, Arghya Sadhukhan, Noor-ul H. Khan, S. Saravanan, Rukhsana I. Kureshy,
Sayed H. R. Abdi, Hari C. Bajaj. Asymmetric hydrocyanation of nitro olefins catalyzed
by Al(III) salen complex. Accepted in Chemcatchem 2014. [DOI:
10.1002/cctc.201402373]
5. Nabin Ch. Maity, Prasanta Kumar Bera, S. Saravanan, Sayed H. R. Abdi, Rukhsana I.
Kureshy, Noor-ul H. Khan, Hari C. Bajaj. Diethyl tartrate linked chiral macrocyclic
Mn(III) salen complex: as recyclable catalyst for enantioselective epoxidation of nonfunctionalized
alkenes and oxidative kinetic resolution of racemic secondary alcohols.
Accepted in Chempluschem 2014 [DOI: 10.1002/cplu.201402131]
6. Manish Kumar, S. Saravanan, Noor-ul H. Khan, Rukhsana I. Kureshy, Sayed H. R.
Abdi, and Hari C. Bajaj. Unravelling a new class of Chiral Organo-catalyst for
Asymmetric Ring Opening Reaction of Meso Epoxides with Anilines. Org. Lett. 2014,
16 (11), 2798–2801.
7. S. Saravanan, Noor-ul H. Khan, Rukhsana I. Kureshy, Sayed H. R. Abdi, and Hari C.
Bajaj, Small Molecule as a Chiral Organocatalyst for Asymmetric Strecker Reaction: An
Effective Protocol for the Synthesis of Chiral Hydantoin. ACS Catalysis, 2013, 3 (12),
2873–2880.
8. S. Saravanan, Noor-ul H. Khan, Prasanta K. Bera, Rukhsana I. Kureshy, Sayed H. R.
Abdi, Prathibha Kumari, Hari C. Bajaj, Catalysis of Enantioselective Strecker Reaction in
the Synthesis of D-Homophenylalanine Using Recyclable, Chiral, Macrocyclic Mn(III)–
Salen Complexes. Chemcatchem, 2013, 5, 1374.
9. Debashis Ghosh, Debashis Sahu, S. Saravanan, Sayed H. R. Abdi, Bishwajit Ganguly,
Noor-ul H. Khan, Rukhsana I. Kureshy and Hari C. Bajaj, Synthetically amenable amide
derivatives of tosylated-amino acids as organocatalysts for enantioselective allylation of
aldehydes: computational rationale for enantioselectivity. Org. Biomol. Chem., 2013, 11,
3451-3460.
10. S. Saravanan, Arghya Sadhukhan, Noor-ul H. Khan, Rukhsana I. Kureshy, Sayed H. R.
Abdi, and Hari C. Bajaj, C2-Symmetric Recyclable Organocatalyst for Enantioselective
Strecker Reaction for the Synthesis of α-Amino Acid and Chiral Diamine- an
Intermediate for APN Inhibitor, J. Org. Chem. 2012, 77, 4375−4384.
11. Arghya Sadhukhan, S. Saravanan, Noor-ul H. Khan, Rukhsana I. Kureshy, Sayed H. R.
Abdi, and Hari C. Bajaj, Modified Asymmetric Strecker Reaction of Aldehyde with
Secondary Amine: A Protocol for the Synthesis of S‑Clopidogrel (An Antiplatelet
Agent), J. Org. Chem. 2012, 77, 7076−7080.
12. Arpan K. Shah, Noor-ul H. Khan, Govind Sethia, S. Saravanan, Rukhsana I. Kureshy,
Sayed H. R. Abdi, Hari C. Bajaj, Tin exchanged zeolite as catalyst for direct synthesis of
α-amino nitriles under solvent-free conditions, Appl. Catal., A, 2012, 419– 420, 22–30.
13. Noor-ul H. Khan, Arghya Sadhukhan, Nabin C. Maity, Rukhsana I. Kureshy, Sayed H.R.
Abdi, S. Saravanan, Hari C. Bajaj, Enantioselective Oacetylcyanation/
cyanoformylation of aldehydes using catalysts with built-in crown etherlike
motif in chiral macrocyclic V(V) salen complexes, Tetrahedron, 2011, 67, 7073-
7080.
14. S. Saravanan, Rukhsana I. Kureshy, Sayed H. R. Abdi, Hari C. Bajaj, Mn(III) salen
complexes-catalyzed enantioselective addition of trimethylsilylcyanide to Nbenzylimines
in the presence of 4-phenyl pyridine-N-oxide as an additive, Noor-ul H.
Khan, Tetrahedron: Asymmetry 2010, 21, 2076–2080.
15. Noor-ul H. Khan, S. Saravanan, Rukhsana I. Kureshy, Sayed H.R. Abdi, Arghya
Sadhukhan, Hari C. Bajaj, Asymmetric addition of trimethylsilylcyanide to Nbenzylimines
catalyzed by recyclable chiral dimeric V(V) salen complex, J. Organomet.
Chem. 2010, 695, 1133–1137.
16. Rukhsana I. Kureshy, Santosh Agrawal, S. Saravanan, Noor-ul H. Khan, Arpan K. Shah,
Sayed H. R. Abdi , Hari C. Bajaj, E. Suresh, Direct Mannich reaction mediated by
Fe(Cp)2PF6 under solvent-free conditions, Tetrahedron Lett. 2010, 51, 489–494.
17. S. Saravanan, Noor-ul H. Khan, Rukhsana I. Kureshy, Sayed H. R. Abdi, and Hari C.
Bajaj. An efficient and recyclable chiral V(V) dinuclear catalyst for enantioselective
Strecker reaction: A comparative and mechanistic studies for the reactivity of organic and
alkali cyanide sources. (Communicated)
Nanoporous Benzoxazole Networks by Silylated Monomers, Their Exceptional Thermal Stability, and Carbon Dioxide Capture Capacity
H. A. Patel, D. Ko, C. T. Yavuz*
Chem. Mater., 26 (23), 6729–6733 (2014). [DOI]
Chem. Mater., 26 (23), 6729–6733 (2014). [DOI]
The pursuit of synthetic routes for design and preparation of nanoporous polymeric networks with inherent permanent microporosity and functionality through bottom-up methodologies remains a driving force in developing CO2-philic materials. We report nanoporous, processable, benzoxazole-linked covalent organic polymers (Box-COPs) that show exceptional thermal stability up to 576 °C. Box-COPs can be formed into films thanks to the silylation that is used to guide polymeric network formation. Surface areas of up to 606 m2 g–1 and narrow pore sizes of 4.36 Å were observed with a CO2 uptake capacity of 139.6 mg g–1 at 273 K and 1 bar. Box-COPs were stable in boiling water for a week without deteriorating CO2 capture capacity.
Charge induced formation of crystalline network polymers
A. A. Raja, C. T. Yavuz*
RSC Adv., 4 (104), 59779 - 59784 (2014). [DOI] [pdf]
RSC Adv., 4 (104), 59779 - 59784 (2014). [DOI] [pdf]
Order in purely organic network polymers is hard to achieve, as reversible, dynamic covalent bond formation is required. Strategies have focused on thermodynamically controlled transformations, as kinetics would not seemingly favour reversibility. Herein, we report formation of crystalline network polymers under kinetically favoured conditions by using quaternary ammonium salt linked networks. Charged bulky bridges align, even under fast reaction times (20 minutes) if the rotational freedom is granted. Adding vicinal methyl substituents blocks the ordering, hence forming amorphous networks. Raman experiments and SEM images reveal stacking of 2D layers.
Nanostructure and mechanical properties of aromatic polyamide and reactive organoclay nanocomposites
M. U. Alvi, S. Zulfiqar, C. T. Yavuz, H.S. Kweon, M. I. Sarwar*
Mater. Chem. Phys., 147, 636-643, (2014). [DOI]
Aromatic polyamide/organoclay nanocomposites were synthesized using the solution blending technique. Treatment of montmorillonite clay with p-phenylenediamine produced reactive organophilic clay for good compatibility with the matrix. Polyamide chains were prepared by condensing a mixture of 1,4-phenylenediamine and 4-4′-oxydianiline with isophthaloyl chloride under anhydrous conditions. These chains were end capped with carbonyl chloride using 1% extra acid chloride near the end of reaction to develop the interactions with organoclay. The dispersion and structure–property relationship were monitored using FTIR, XRD, FE-SEM, TEM, DSC and tensile testing of the thin films. The structural investigations confirmed the formation of delaminated and disordered intercalated morphology with nanoclay loadings. This morphology of the nanocomposites resulted in their enhanced mechanical properties. The tensile behavior and glass transition temperature significantly augmented with increasing organoclay content showing a greater interaction between the two disparate phases.
Mater. Chem. Phys., 147, 636-643, (2014). [DOI]
Aromatic polyamide/organoclay nanocomposites were synthesized using the solution blending technique. Treatment of montmorillonite clay with p-phenylenediamine produced reactive organophilic clay for good compatibility with the matrix. Polyamide chains were prepared by condensing a mixture of 1,4-phenylenediamine and 4-4′-oxydianiline with isophthaloyl chloride under anhydrous conditions. These chains were end capped with carbonyl chloride using 1% extra acid chloride near the end of reaction to develop the interactions with organoclay. The dispersion and structure–property relationship were monitored using FTIR, XRD, FE-SEM, TEM, DSC and tensile testing of the thin films. The structural investigations confirmed the formation of delaminated and disordered intercalated morphology with nanoclay loadings. This morphology of the nanocomposites resulted in their enhanced mechanical properties. The tensile behavior and glass transition temperature significantly augmented with increasing organoclay content showing a greater interaction between the two disparate phases.
Melamine based porous organic amide polymers for CO2 capture
S. Zulfiqar, M. I. Sarwar*, C. T. Yavuz*
RSC Adv., 4, 52263–52269, (2014). [DOI]
RSC Adv., 4, 52263–52269, (2014). [DOI]
Amide based porous organic polymers were synthesized by the reaction of 1,3,5-benzenetricarbonyl trichloride with 2,4,6-triamino-1,3,5-triazine using two different solvents. Polyamide chains were derived from tri-functional monomers and their relative properties were compared in both media. These polymers were subjected to various analyses including FTIR, XRD, TGA, BET surface area and pore size analysis, FESEM and CO2 adsorption measurements. Thermal and chemical stability was achieved through strong amide building blocks in the polymer structure. The basic ring nitrogen and amide groups in the polyamide networks had the affinity to capture CO2. The maximum CO2 uptake of 2.99 cm3 g−1 (0.134 mmol g−1) at 273 K and 1 bar was obtained with the polyamide synthesized in DMAc–NMP (PA-1), revealing better efficiency than the polyamide prepared using 1,4-dioxane (PA-2) due to higher porosity and improved surface area. These thermally stable polyamides are anticipated to be good sorbents for CO2 capture in hostile environments.
Ms. Nesibe Ayse Dogan
Ph. D. Student
September 2014 - present
Education:
MS Sabanci University, Istanbul, Turkey
BS Bilkent University, Ankara, Turkey
Email: nesibeayse@kaist.ac.kr
September 2014 - present
Education:
MS Sabanci University, Istanbul, Turkey
BS Bilkent University, Ankara, Turkey
Email: nesibeayse@kaist.ac.kr
Ms. Yeongran Hong
MS Student
September 2014 - present
Education:
BS Seoul National University of Science and Technology
Email: yr123@kaist.ac.kr
September 2014 - present
Education:
BS Seoul National University of Science and Technology
Email: yr123@kaist.ac.kr
Conductive nanocomposite materials derived from SEBS-g-PPy and surface modified clay
M. Zahra, S. Zulfiqar, C. T. Yavuz, H.S. Kweon, M. I. Sarwar*
Compos. Sci. Technol., 100, 44–52, (2014). [DOI]
Compos. Sci. Technol., 100, 44–52, (2014). [DOI]
Conductive nanocomposites were synthesized from surface modified clay and polypyrrole grafted triblock copolymer, polystyrene-b-poly(ethylene-co-butylene)-b-polystyrene (SEBS-g-PPy). The grafting of PPy was carried out on SEBS using FeCl3 as an oxidant and the formation of subsequent materials was monitored by IR, 1H NMR spectroscopy and Gel permeation chromatography (GPC). Surface treatment of the clay was carried out by ion exchange method using the cationic salt of 2,2-bis[4-(4-aminophenoxy)phenyl]propane for better adhesion with the polymer matrix. Thin composite films containing 1–8-wt.% organoclay were investigated by FTIR, XRD, TEM, tensile testing, TGA, DSC and electrical conductivity measurements. The molar mass as determined by GPC was around 37,000. XRD pattern and TEM images described good dispersion of clay platelets in the nanocomposites. Tensile testing revealed improvement in mechanical properties up to 3-wt.% of organoclay. The bulk electrical conductivity was increased up to 7-wt.% with increase in resonance of delocalized electrons of stretched PPy chains due to hydrogen bonding with organoclay in the nanocomposites. Thermal decomposition temperatures of the nanocomposites were in the range 435–448 °C. The decomposition of the nanocomposites was observed at higher temperatures relative to the pure polymer matrix with increasing clay loading. The weight retained after 900 °C was approximately equal to the amount of organoclay added in the composites. These composite materials exhibited improvement in glass transition temperature as compared to SEBS-g-PPy.
Prof. Cafer, Jeongin, and Jeehye participated in NANO-7 held in Niagara Fall, Canada!
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| Niagara Falls |
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| Night view of Niagara Falls |
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| CN Tower, Toronto |
Exceptional organic solvent uptake by disulfide-linked polymeric networks
Disulfide-linked covalent organic polymers (COPs) were prepared through catalyst-free oxidative coupling polymerization. Owing to the excellent swelling behavior, low cost, and efficient synthesis, these materials can be promising materials for removal of organics in concentrated streams. COPs show 1,4-dioxane uptake up to 1.8 g g−1.
Nanoporous covalent organic polymers incorporating Tröger’s base functionalities for enhanced CO2 capture
J. Byun, S. H. Je, H. A. Patel, A. Coskun,* C. T. Yavuz*
J. Mater. Chem. A, 2, 12507-12512, 2014. [DOI] [pdf] [WoS]
The CO2 uptake capacity and CO2/N2 selectivity of Tröger’s base–bridged nanoporous covalent organic polymers (TB-COPs) were investigated. TB-COPs were synthesized by reacting amine terminals of tetrahedral monomers - namely, tetraanilyladamantane and tetraanilylmethane - with dimethoxymethane in a one–pot reaction under relatively mild conditions. Interestingly, these two tetrahedral monomers formed nanoporous polymers with substantially different surface areas. While the trögerization of tetraanilyladamantane monomer (TB-COP-1) exhibit high surface area of 1340 m2 g-1, that of tetraanilylmethane monomer (TB-COP-2) is found to be only 0.094 m2 g-1. This unusual phenomenon can be explained by the proximity of amino moieties to each other within the monomeric unit. Shorter distance between the amino groups enables intramolecular cyclization along with the intermolecular one, thus resulting in much lower porosity. TB-COP-1 exhibits significant CO2 uptakes up to 5.19 and 3.16 mmol g-1 at 273 and 298K under ambient pressure, and CO2/N2 selectivities of 79.2 and 68.9 at 273 and 298K at 1 bar for the gas mixture of CO2:N2 in the ratio of 0.15:0.85. It is noteworthy that TB-COP-1 showed remarkable selectivity retention with rising temperature from 273 to 298 K.
J. Mater. Chem. A, 2, 12507-12512, 2014. [DOI] [pdf] [WoS]
The CO2 uptake capacity and CO2/N2 selectivity of Tröger’s base–bridged nanoporous covalent organic polymers (TB-COPs) were investigated. TB-COPs were synthesized by reacting amine terminals of tetrahedral monomers - namely, tetraanilyladamantane and tetraanilylmethane - with dimethoxymethane in a one–pot reaction under relatively mild conditions. Interestingly, these two tetrahedral monomers formed nanoporous polymers with substantially different surface areas. While the trögerization of tetraanilyladamantane monomer (TB-COP-1) exhibit high surface area of 1340 m2 g-1, that of tetraanilylmethane monomer (TB-COP-2) is found to be only 0.094 m2 g-1. This unusual phenomenon can be explained by the proximity of amino moieties to each other within the monomeric unit. Shorter distance between the amino groups enables intramolecular cyclization along with the intermolecular one, thus resulting in much lower porosity. TB-COP-1 exhibits significant CO2 uptakes up to 5.19 and 3.16 mmol g-1 at 273 and 298K under ambient pressure, and CO2/N2 selectivities of 79.2 and 68.9 at 273 and 298K at 1 bar for the gas mixture of CO2:N2 in the ratio of 0.15:0.85. It is noteworthy that TB-COP-1 showed remarkable selectivity retention with rising temperature from 273 to 298 K.
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