Guanjun Chang

Name:

Organization: University of Science and Technology of China

Department: 1 State Key Laboratory Cultivation Base for Nonmetal Composite and Functional Materials & School of Material Science and Engineering

Title:

TOPICS

Polymer

Polyimide Polybenzimidazoles Polysulfone

Chemicals
References

High and Selective Carbon Dioxide Capture in Nitrogen-Containing Aerogels via Synergistic Effects of Electrostatic In-Plane and Dispersive π–π-Stacking Interactions

Co-reporter:Li Yang, Guanjun Chang, and Dapeng Wang

ACS Applied Materials & Interfaces May 10, 2017 Volume 9(Issue 18) pp:15213-15213

Publication Date(Web):April 27, 2017

DOI:10.1021/acsami.7b02077

A new strategy for CO2 capture is reported based on the synergistic effect of electrostatic in-plane and dispersive π–π-stacking interactions of amide and indole with CO2. Density functional theory illustrated that the amide group can have an increased ability to capture CO2 molecules that were just desorbed from an adjacent indole unit. We used this strategy to fabricate a microporous aerogel that exhibited a superior CO2 capture performance in both dry and wet conditions. The proposed synergistic effect is expected to be a new rationale for the design of CO2 capture materials.Keywords: CO2 capture; in-plane and π−π-stacking interactions; nitrogen-containing aerogels; synergistic effect;

Facile synthesis of new coumarin-based colorimetric and fluorescent chemosensors: Highly efficient and selective detection of Pd2+ in aqueous solutions

Co-reporter:Li Yang, Cheng Wang, Guanjun Chang, Xianyan Ren

Sensors and Actuators B: Chemical 2017 Volume 240(Volume 240) pp:

Publication Date(Web):1 March 2017

DOI:10.1016/j.snb.2016.08.132

•A new type of coumarin derivative has been designed and easily prepared.•The fluorescence sensor exhibits excellent sensitivity and selectivity for Pd2+.•The sensing process is based on the ICT fluorescence quenching mechanism.•The detection can also be performed in a visualized manner.Based on the intramolecular charge transfer (ICT) fluorescence quenching mechanism, a ready-to-use colorimetric coumarin coordinative probe has been designed and successfully achieved for the efficient detection of Pd2+ in aqueous buffer media (pH 7.0), which promisingly meets real-world challenges through a facile synthetic route, fast response, by-eye visualization, regenerative-action, high selectivity and sensitivity. The UV–vis spectra, mass spectra and density function theory studies have indicated that a 1:1 complex is formed between the probe and Pd2+. The detection limit of Pd2+ is up to 2.9 × 10−7 M. This reagent could even be used for estimation of Pd2+ in samples with its known concentrations with considerable accuracy (ca. 4.1-4.8% error). Moreover, the binding affinity and fluorescence quenching degree of 1 with Pd2+ are superior to those of 2. It has been demonstrated that the sensitive property of the chemosensors for Pd2+ is highly dependent on the fine structure of the conjugated compounds.Based on the ICT fluorescence quenching mechanism, a new type of coumarin derivative has been successfully achieved as an efficient colorimetric and fluorescent sensor for Pd2+ in aqueous solutions.Download high-res image (65KB)Download full-size image

Rational design of a novel indole-based microporous organic polymer: enhanced carbon dioxide uptake via local dipole–π interactions

Co-reporter:Guanjun Chang, Zhenfang Shang, Tao Yu and Li Yang

Journal of Materials Chemistry A 2016 vol. 4(Issue 7) pp:2517-2523

Publication Date(Web):18 Jan 2016

DOI:10.1039/C5TA08705H

An indole-based microporous organic polymer (PINK) has been obtained by the condensation polymerization of 1,3,5-tris-(4-fluorobenzoyl)benzene with 3,3′-diindolylmethane via a catalyst-free nucleophilic substitution reaction. Due to the local dipole–π interactions between indole and carbon dioxide (CO2), the uptake capacity for CO2 reaches up to 16.0 wt% (1.0 bar, 273 K), and the high (CO2/N2 = 15, CO2/CH4 = 32) selectivities of the polymer make it a promising material for potential application in gas separation. Furthermore, the hydrogen storage is up to 2.48 wt% (1.0 bar, 77 K). In comparison to the reported porous organic polymers, the preparative strategy exhibits cost-effective advantages, which are essential for scale-up preparation. Its good performance for H2 storage and CO2 separation suggests that PINK with a large specific surface area shows potential use in clean energy applications and the environmental field.

Soluble N-substituted poly(benzimidazole imide)s via CN coupling reaction

Co-reporter:Zhenfang Shang;Li Yang

Polymer International 2016 Volume 65( Issue 3) pp:332-338

Publication Date(Web):

DOI:10.1002/pi.5060

Abstract

Novel heat-resistant N-substituted poly(benzimidazole imide)s (PBIIs) with good solubility were synthesized via a C − N coupling reaction. A model reaction was carried out to assist in determining the optimal reaction conditions for the polymerization and to elucidate the chemical structures of the polymers. The structures of the resulting polymers were characterized by means of Fourier transform infrared and elemental analysis; the results showed good agreement with the proposed structures. The resulting PBIIs exhibited high glass transition temperatures (T_g > 290 ^oC) and good thermostability (T_5% > 440 ^oC). The thermal behavior in air of the PBII polymers suggests that they can be considered as a new class of high performance polyimides. © 2016 Society of Chemical Industry

High performance poly(N-aryleneindole ether) containing pyridine units as a novel acid response fluorescent detector

Co-reporter:Qiaojiao Wang;Li Xiong;Fanghua Zhu;Li Yang

Polymer International 2016 Volume 65( Issue 7) pp:841-844

Publication Date(Web):

DOI:10.1002/pi.5145

Abstract

A novel high-performance polyindole containing a pyridine ring (P1) was successfully prepared by the catalyst-free nucleophilic substitution polycondensation of 4-hydroxyindole with 2,6-difluoropyridine via a C − N and C − O coupling reaction process. This semirigid polyindole P1 exhibits good thermal stability, and it can be dissolved well in common organic solvents. Fluorescent spectral studies indicate that the resulting polymer shows blue-light emission at 402 nm due to the effect of intramolecular charge transfer caused by the donor − acceptor interaction between its indole and pyridine units. Moreover, the fluorescence intensity of P1 could be altered by protonation and deprotonation. Such behaviour enables it to be utilized as one kind of acid response fluorescent polymer sensor. © 2016 Society of Chemical Industry

Poly(imide ether sulphone) as new soluble high performance polymer

Co-reporter:Guanjun Chang;Qiaojiao Wang;Li Xiong;Li Yang

Polymer Science, Series B 2016 Volume 58( Issue 3) pp:329-333

Publication Date(Web):2016 May

DOI:10.1134/S1560090416030039

Poly(imide ether sulphone) as novel high-performance polymer has been obtained by the condensation polymerization of 4,4'-bis(4-fluorophthalimido) diphenyl ether with 4,4'-sulfonyldiphenol via aromatic nucleophilic substitution reaction. Its structure was confirmed by means of FTIR and NMR spectroscopy, elemental analysis. Differential scanning calorimetry and thermal analysis measurements showed that synthesized polymer possessed high glass transition temperature (Tg = 210°C) and good thermal stability with high decomposition temperatures (Td > 480°C). Prepared polymer film showed good light transmittance and mechanical strength.

Rational design of a fluorescent poly(N-aryleneindole ether sulfone) switch by cation–π interactions

Co-reporter:Guanjun Chang, Li Yang, Shenye Liu, Runxiong Lin and Jingsong You

Polymer Chemistry 2015 vol. 6(Issue 5) pp:697-702

Publication Date(Web):13 Nov 2014

DOI:10.1039/C4PY01472C

Semirigid poly(N-aryleneindole ether sulfone) (PESIN) as a fluorescence emission on–off switch has been successfully achieved via the cation–π interactions. The adjustment of the protonation/deprotonation status of pyridine that regulates the formation of cation–π interactions is definitely the determinant.

Hydrogen bond cross-linked sulfonated poly(imino ether ether ketone) (PIEEK) for fuel cell membranes

Co-reporter:Guanjun Chang, Zhenfang Shang, Li Yang

Journal of Power Sources 2015 Volume 282() pp:401-408

Publication Date(Web):15 May 2015

DOI:10.1016/j.jpowsour.2015.02.077

•Hydrogen bond cross-linked sulfonated SPIEEK membranes have been obtained.•The interchain hydrogen bonding formed because of the introduction of imino groups.•SPIEEK membranes displayed much better resistance to swelling.•SPIEEK membrane show the proton conductivity of 0.118 and 0.154 S/cm at 80 °C.•SPIEEK membranes exhibit good mechanical properties and lower methanol permeability.A new diamine monomer, 3,3′-dihydroxydiphenylamine, is prepared by the palladium catalyzed C–N coupling reaction and the following reduction reaction of 3-bromoanisole and m-anisidine. A series of novel hydrogen bond cross-linked sulfonated poly(imino ether ether ketone) (SPIEEK) are obtained by the copolymerization of sodium 5,5′-carbonylbis(2-fluorobenzene sulfonate), 4,4′-difluorobenzophenone with 3,3′-dihydroxydiphenylamine. The structures of resulting polymers are characterized by means of FT-IR, 1H NMR spectroscopy, and elemental analysis; the results show an agreement with the proposed structure. The resulting SPIEEK membranes display much better resistance to swelling than these without imino groups due to the strong interchain interaction through imino and sulfonic acid groups. The SPIEEK-60 and SPIEEK-80 membrane show the proton conductivity of 0.118 and 0.154 S cm−1 at 80 °C which is higher than Nafion 117 (0.082 S cm−1 at 80 °C). Moreover, the SPIEEK membranes exhibit good mechanical properties and lower methanol permeability due to the hydrogen bondings between the polymer chains.Hydrogen bond cross-linked sulfonated poly(imino ether ether ketone) (PIEEK) for fuel cell membranes A series of novel hydrogen bond cross-linked sulfonated poly(imino ether ether ketone) (SPIEEK) have been obtained. The resulting SPIEEK membranes displayed much better resistance to swelling, higher proton conductivity, good mechanical properties and lower methanol permeability than that of traditional SPEEK due to the hydrogen bondings between the polymer chains.

Synthesis of high-performance polymers via copper-catalyzed amination of dibromoarenes with primary aromatic ether diamines

Co-reporter:Zhenfang Shang;Li Yang

Macromolecular Research 2015 Volume 23( Issue 10) pp:937-943

Publication Date(Web):2015 October

DOI:10.1007/s13233-015-3125-y

Intermolecular hydrogen bonding of polyiminosulfone

Co-reporter:Guanjun Chang;Li Yang;Xianpan Shi;Lin Zhang;Runxiong Lin

Polymer Science, Series A 2015 Volume 57( Issue 2) pp:251-255

Publication Date(Web):2015 March

DOI:10.1134/S0965545X15020030

Molecular dynamics calculations were made of the distance from the hydrogen atom of the imino group to the oxygen atom of the sulfone group of polyiminosulfone (PIS). The results showed that theoretically there was hydrogen bond formation between the imino group and the sulfone group of PIS. The existence of the hydrogen bonding between the polymer chains of PIS was confirmed by infrared spectrum analysis. Due to the existence of the hydrogen bonding, PIS showed strong molecular interaction with a large cohesive energy density (CED), and a high glass transition temperature (282°C).

Synthesis of indole-based functional polymers with well-defined structures via a catalyst-free C–N coupling reaction

Co-reporter:Guanjun Chang, Li Yang, Shenye Liu, Xuan Luo, Runxiong Lin and Lin Zhang

RSC Advances 2014 vol. 4(Issue 58) pp:30630-30637

Publication Date(Web):02 Jul 2014

DOI:10.1039/C4RA03602F

Poly(N-arylene diindolylmethane)s (PMDINs) with precise structures and high molecular weights (Mw up to 389200) in high yields (up to 95%) were synthesized by the catalyst-free nucleophilic substitution polycondensation of 3,3′-diindolylmethane with different activated difluoro monomers via a C–N coupling reaction process. A model reaction was carried out to assist in determining the optimal reaction conditions for the polymerization and to elucidate the chemical structures of the polymers. The resulting polymers exhibited good thermal stability with high decomposition temperature (T5% ≥ 377 °C). Fluorescent spectral studies indicated that all these PMDINs had strong solid-state fluorescence. Especially, the polymer PMDIN-3 carrying sulfonyl units was a good blue-light emitter with high quantum yields (21.6%, determined against quinine sulfate). The results obtained by cyclic voltammetry suggested that PMDINs possessed good electroactivity. In addition, owing to the electrochemical activity of the indole rings at the 2-position, PMDIN-3 was readily cross-linked by electrochemical oxidation and the cross-linking film was characterized by scanning electron microscopy. High molecular weights and good comprehensive performance of the indole-based polymers suggested that the catalyst-free C–N coupling reaction of indole derivatives with difluoro monomers could be considered as an effective polymerization route for the synthesis of new functional polymers with well-defined structures.

Synthesis of poly(arylene benzimidazole) sulfone (PABIS) and preparation of hollow PABIS microspheres

Co-reporter:Guanjun Chang;Yi Xu;Junxiao Yang;Lin Zhang

Polymer International 2014 Volume 63( Issue 1) pp:158-164

Publication Date(Web):

DOI:10.1002/pi.4469

Abstract

4,4'-Di(benzimidazolyl)benzene sulfone, as the monomer, is very readily available by the reaction of 4,4'-dicarboxydiphenyl sulfone with o-phenylenediamine, and poly(arylene benzimidazole) sulfone (PABIS) has been synthesized by the condensation polymerization of bis(4-fluorophenyl) sulfone with di(benzimidazolyl)benzene sulfone via an N–C coupling reaction. The structure of the polymer was characterized by Fourier transform IR spectroscopy, ¹H NMR spectroscopy and elemental analysis, and the results showed agreement with the proposed structure. DSC and thermogravimetric measurements showed that PABIS possesses a high glass transition temperature (T_g = 321 °C) and good thermal stability with high decomposition temperature (T_d > 530 °C). Additionally, PABIS exhibits good solubility in most polar organic solvents. Based on the good chemical and physical properties, hollow PABIS microspheres with diameters in the range 0.3–1.8 mm were prepared by the micro-liquid technique and the double-layer latex technique. A new double T-channel droplet generator was developed for continuous fabrication of controlled-size hollow PABIS microspheres. The structures of the hollow PABIS microspheres were characterized, and they possessed equal wall thickness and good spherical symmetry. © 2013 Society of Chemical Industry

Poly(imino imino ether ether ketone ketone) as novel soluble heat-resistant polymer

Co-reporter:Li Wang;Li Yang;Runxiong Lin;Lin Zhang

Polymer Science, Series B 2014 Volume 56( Issue 5) pp:639-644

Publication Date(Web):2014 September

DOI:10.1134/S1560090414050170

In this paper, we introduce a novel high-performance polymer, poly(imino imino ether ether ketone ketone), which has been synthesized by the palladium-catalyzed C-N cross coupling reaction of 1,4-bis-(4-bromobenzoyl) benzene and 1,3-bis-(4-aminophenoxy) benzene. The structure of the polymer is characterized by means of 1H NMR spectroscopy and elemental analysis, and the results show a good agreement with the proposed structure. Compared with traditional poly(ether ether ketone)s, the solubility of the synthesized polymer in common organic solvents was higher; it also exhibited high glass transition temperature (Tg = 176°C) and good thermal stability with high decomposition temperature (T5 = 400°C).

Facile synthesis of heat-resistant and photoluminescent poly(N-aryleneindole ether)s via catalyst-free CN/CO coupling reaction

Co-reporter:Guanjun Chang;Li Yang;Junxiao Yang;Yawen Huang;Lin Zhang;Runxiong Lin

Journal of Polymer Science Part A: Polymer Chemistry 2014 Volume 52( Issue 3) pp:313-320

Publication Date(Web):

DOI:10.1002/pola.27014

ABSTRACT

We present here a novel programmable polymerization route for the synthesis of new indole-based polymers via a catalyst-free nucleophilic substitution reaction. The polycondensation of 4-hydroxyindole with different activated difluoro monomers undergoes in N-methylpyrrolidinone, affording soluble poly(N-aryleneindole ether)s (PEINs) with high molecular weights (M_w up to 486,000) in high yields (up to 96%). The structures of the polymers are characterized by means of FT-IR, ¹H NMR spectroscopy and elemental analysis, the results show good agreement with the proposed structures. The resulting polymers are processable and enjoy high glass transition temperatures (T_gs > 180 °C) and thermal stability (T_ds > 420 °C). Thin films of PEINs show great mechanical behaviors with high tensile strength up to 104 Mpa, and good optical transparency. In addition, due to the indole moieties in the main chains, all these PEINs are endowed with significantly strong photonic luminescence in chloroform and display highly solvent-dependent emission bands. Especially, the polymer PEIN-3 carrying sulfonyl units, shows outstanding blue-light emission with high quantum yields (45.2%, determined against quinine sulfate). The results obtained by cyclic voltammetry suggest that PEINs possess good electroactivity. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 313–320

Poly(arylene benzimidazole)s as novel high-performance polymers

Co-reporter:Guanjun Chang, Junxiao Yang, Yawen Huang, Ke Cao and Lin Zhang

Polymer Journal 2013 45(12) pp:1188-1194

Publication Date(Web):June 5, 2013

DOI:10.1038/pj.2013.51

Series of novel poly(arylene benzimidazole)s (PABIs) was obtained by condensation polymerization of aromatic bifluorides with the monomers of di(benzimidazolyl)benzenes (synthesized by reaction of the isomeric phthalic acids with o-phenylenediamine) via a C–N coupling reaction. The structures of this series of polymers were characterized by Fourier transform infrared, proton nuclear magnetic resonance (1H NMR) spectroscopy and elemental analysis, and the results showed good agreement with the proposed structures. These synthesized polymers exhibited relatively high glass-transition temperatures (Tg>240 °C), good thermal stability with high decomposition temperatures (Td>450 °C) and excellent solubility in organic solvents. On the atomic scale, the molecular simulation results indicated that the PABI polymers exhibited a zigzag molecular chain structure with a high free volume fraction due to the different linkage modes of the monomers in the polymerization process. On the macro level, the PABI polymers possessed high tensile strength with good toughness; the mechanical behavior of the PABI polymers indicates that they can be considered a new class of high-performance polymers.

Synthesis of poly(imino imino ketone) (PIIK) and preparation of heat resistant PIIK foam

Co-reporter:Guanjun Chang, Li Yang, Junxiao Yang, Yawen Huang, Ke Cao, Lin Zhang, Runxiong Lin

Polymer 2013 Volume 54(Issue 18) pp:5043-5049

Publication Date(Web):16 August 2013

DOI:10.1016/j.polymer.2013.07.009

Poly(imino imino ketone) (PIIK) was synthesized via palladium-catalyzed C–N cross coupling reaction of 1,4-bis-(4′-bromobenzoyl) benzene and p-phenylenediamine. In view of its good thermal stability and solubility, PIIK foams with low density between 80 mg/cm3–350 mg/cm3 have been prepared via thermal induced phase separation and freeze-drying technology. The PIIK foam possessed high glass transition temperature (Tg = 193 °C) and good thermal stability with high decomposition temperature (Td = 350 °C). Furthermore, these achieved foams also exhibited excellent mechanical properties, such as high modulus and compressive strength, as well as great elongation at break (ca. 20%).

Facile synthesis of soluble aromatic poly(amide amine)s via CN coupling reaction: Characterization, thermal, and optical properties

Co-reporter:Guanjun Chang;Li Yang;Junxiao Yang;Yawen Huang;Ke Cao;Lin Zhang;Runxiong Lin

Journal of Polymer Science Part A: Polymer Chemistry 2013 Volume 51( Issue 22) pp:4845-4852

Publication Date(Web):

DOI:10.1002/pola.26910

ABSTRACT

Aromatic poly(amide amine)s (APAAs), as novel high-performance polymers, have been obtained by the condensation polymerization of N,N'-bis(4-bromobenzoyl)-p-phenylenediamine with two different primary aromatic diamines via palladium-catalyzed aryl amination reaction. The structures of the polymers are characterized by means of FTIR, ¹H NMR spectroscopy, and elemental analysis, the results show a good agreement with the proposed structures. DSC and TGA measurements exhibit that polymers possess high glass transition temperature (T_g > 240 °C) and good thermal stability with high decomposition temperatures (T₅ > 400 °C). These novel polymers also display good solubility. In addition, due to its special structure, APAA-2 is endowed with significantly strong photonic luminescence in N,N-dimethylformamide and good electroactivity. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4845–4852

Synthesis of poly (imino ketone)s by palladium catalysis C-N cross-coupling reaction

Co-reporter:Guanjun Chang;Yang Mei;Lin Zhang;Runxiong Lin

Polymer Science, Series B 2012 Volume 54( Issue 5-6) pp:323-329

Publication Date(Web):2012 May

DOI:10.1134/S1560090412060024

In this paper, taking Pd2(dba)3 as catalyst and 2,2′-bis-(diphenylphosphino)-1,1′-binaphtyl as ligand, six kinds of poly(imino ketone)s (PIKs) with different structures have been synthesized via palladium catalysis C-N cross-coupling reaction. The structures of polymers synthesized was characterized by means of FTIR and NMR spectroscopy, the results showed an agreement with the proposed structures. The influential disciplines of monomer concentration and catalysis system to PIKs molecular weight were discussed. Differential scanning calorimetry measurement showed that PIKs possessed high glass transition temperatures (Tg > 150°C).

Poly(aryl imino sulfone)s as new high-performance engineering plastics

Co-reporter:Guanjun Chang;Xuan Luo;Yi Xu;Hongju Hu;Lidong Wei;Lin Zhang

Polymer Bulletin 2012 Volume 68( Issue 1) pp:95-111

Publication Date(Web):2012 January

DOI:10.1007/s00289-011-0527-7

Poly(aryl imino sulfone)s (PAISs) as novel high-performance polymers have been obtained by the condensation polymerization of 4,4′-dibromodiphenyl sulfone with different primary aromatic diamines via Palladium-catalyzed aryl amination reaction. The influence of the halogen-containing monomers, solvent, concentration, and temperature on the polycondensation reaction was investigated. The structure of polymers synthesized was characterized by means of FT–IR, NMR spectroscopy, and elemental analysis, the results showed an agreement with the proposed structure. Differential scanning calorimetry and thermal analysis measurements showed that polymers possessed high glass transition temperature (Tg > 145 °C) and good thermal stability with high decomposition temperatures (TD > 450 °C). These novel polymers also exhibited good mechanical behaviors and good solubility.

Rational design of a novel indole-based microporous organic polymer: enhanced carbon dioxide uptake via local dipole–π interactions

Co-reporter:Guanjun Chang, Zhenfang Shang, Tao Yu and Li Yang

Journal of Materials Chemistry A 2016 - vol. 4(Issue 7) pp:NaN2523-2523

Publication Date(Web):2016/01/18

DOI:10.1039/C5TA08705H