QingMin Chen

Name: Qing Min Chen; 陈庆民

Organization: Nanjing University , China

Department: Department of Polymer Science & Engineering

Title: NULL(PhD)

Chemicals
References

The icephobicity comparison of polysiloxane modified hydrophobic and superhydrophobic surfaces under condensing environments

Co-reporter:Yuanyi Wang, Jun Liu, Mingzhen Li, Qingjun Wang, Qingmin Chen

Applied Surface Science 2016 Volume 385() pp:472-480

Publication Date(Web):1 November 2016

DOI:10.1016/j.apsusc.2016.05.117

Highlights

•: Different polysiloxane modified surfaces were prepared by etching & coating process.
•: The wettabilities and icephobicities were studied under condensate environment.
•: Superhydrophobicities deteriorated diversely after condensation occurred.
•: The air cushion played a vital role to superhydrophobicity in icephobic application.

Influence of different chemical modifications on the icephobic properties of superhydrophobic surfaces in a condensate environment

Co-reporter:Yuanyi Wang, Mingzhen Li, Ting Lv, Qingjun Wang, Qingmin Chen and Jianfu Ding

Journal of Materials Chemistry A 2015 vol. 3(Issue 9) pp:4967-4975

Publication Date(Web):16 Jan 2015

DOI:10.1039/C4TA07077A

Three superhydrophobic surfaces have been prepared on an aluminium substrate, which was roughened by acid etching to form a nano-/micro-topological surface structure, and then the surface was modified by coating with a PTES (a fluorinated coupling agent), TTPS (a siloxane coupling agent) or PA (an aliphatic coupling agent) layer. Their surface wettability in terms of water contact angle (CA), sliding angle (SA) and water droplet impact dynamics was studied under different humidities at −10 °C. The reduction of ice adhesion was also investigated under both ambient and condensate environments. The results indicated that the icephobic properties of these three superhydrophobic surfaces in the sub-zero environment varied wildly. The PTES surface can maintain excellent sliding and rebounding ability of a water droplet even under extremely condensate conditions (−10 °C and relative humidity (RH) 90%), while others cannot. It is worth noting that the ice adhesion obviously increased under the condensate environment, but no apparent ice-anchoring effect was observed on any of the three superhydrophobic surfaces. In addition, a water condensing dynamic study at sub-zero temperature revealed a distinctive Leidenfrost phenomenon-like jumping behavior of condensed droplets on all three superhydrophobic surfaces with the highest jumping scale and frequency on the PTES surface. The excellent icephobic property of the PTES surface indicates that the choice of a suitable chemical modification for superhydrophobic surfaces has a significant influence on preserving water-repellency and icephobicity under extremely condensing conditions.

Wetting transition of the ordered nanoporous matrix layer under impact and static pressure

Co-reporter:Jian Xue, Peibo Su, Wenwen Dong, Xieqiang Jiang, Qingmin Chen, Qingjun Wang

Applied Surface Science 2015 Volume 353() pp:636-642

Publication Date(Web):30 October 2015

DOI:10.1016/j.apsusc.2015.06.003

Highlights

•: The hydrophobicity of APTS modified surface decreased quickly under the compact pressure of droplet.
•: After applying an enough hydraulic pressure, the hydrophobicity could not be restored automatically.
•: The wettability of APTS modified surface occurs spontaneously in immersion conditions.
•: The critical pressure of PFO modified surfaces were much smaller than the static energy barrier ΔP.

Verification of Icephobic/Anti-icing Properties of a Superhydrophobic Surface

Co-reporter:Yuanyi Wang, Jian Xue, Qingjun Wang, Qingmin Chen, and Jianfu Ding

ACS Applied Materials & Interfaces 2013 Volume 5(Issue 8) pp:3370

Publication Date(Web):March 28, 2013

DOI:10.1021/am400429q

Four aluminum surfaces with wettability varied from superhydrophilic to superhydrophobic were prepared by combining an etching and a coating process. The surface wettability was checked in terms of water contact angle (CA) and sliding angle (SA) under different humidity at −10 °C. High-speed photography was applied to study water droplet impact dynamics on these surfaces. It was found that single and successive water droplets could rebound on the superhydrophobic surface and roll off at a tilt angle larger than 30° under an extremely condensing weather condition (−10 °C and relative humidity of 85–90%). In addition, the superhydrophobic surface showed a strong icephobic property, the ice adhesion on this surface was only 13% of that on the superhydrophilic surface, though they had a similar nano/microtopological structure. Moreover, this superhydrophobic surface displayed an excellent durability of the icephobic property. The ice adhesion only increased to 20% and 16% of that on the superhydrophobic surface after the surface was undergone 20 icing/ice-breaking cycles and 40 icing/ice-melting cycles, respectively. Surface profile and XPS studies on these surfaces indicated a minor damage of the surface nano/microstructure and the coating layer upon these multiple ice-breaking and ice-melting processes. Therefore, this superhydrophobic surface could be a good candidate for icephobic applications.Keywords: contact angle; ice adhesion; ice-repellent; impact dynamics; relative humidity; sliding angle; superhydrophobic; temperature;

Superhydrophobic surfaces fabricated by spray-coating micelle solutions of comb copolymers

Co-reporter:Zhe Cui;Jianfu Ding;Ludmila Scoles;Qingjun Wang

Colloid and Polymer Science 2013 Volume 291( Issue 6) pp:1409-1418

Publication Date(Web):2013 June

DOI:10.1007/s00396-012-2876-7

A series of comb copolymers (poly(arylene alkylene ether) (FPAE)-polystyrene (PS)) with a highly fluorinated FPAE main chain and narrow dispersed PS-grafted chains have been prepared. They are used to prepare micelle solutions in methanol/acetone (M/A) mixed solvents which are good for the FPAE main chains and poor for the PS-grafted chains. In these solutions, the PS-grafted chains form the cores and the FPAE main chains form the corona layers of micelle particles. Uniform micelle particles are achieved because of the narrow molecular weight dispersion of the PS chain length. The micelle solutions are spray-coated onto glass substrates to fabricate hydrophobic surfaces. It is found that the stability of the micelle particles increases with the length of the PS-grafted chains, which further influences the morphology and hydrophobicity of the spray-coated films. The effects of the M/A ratio and the copolymer concentration on the morphology and hydrophobicity of the coating surfaces are also studied. The results prove that a binary nano/microsurface structure is important to achieve a superhydrophobic surface with a low contact angle hysteresis. This binary structure is formed from conglomeration of micelle particles by spray coating the micelle solutions. The best sample reported in this paper has a static contact angle of 163° and a sliding angle of 5.9°. This fabrication procedure is facile, less time consuming, and easily applicable for large-scale surface treatment.

Effect of annealing on phase separation and mechanical properties of epoxy/ATBN adhesive

Co-reporter:Dan He, Xiaodong Ding, Pengshan Chang, Qingmin Chen

International Journal of Adhesion and Adhesives 2012 Volume 38() pp:11-16

Publication Date(Web):October 2012

DOI:10.1016/j.ijadhadh.2012.04.006

Amine-terminated butadiene acrylonitrile (ATBN) was applied as curing agents for diglycidyl ether of bisphenol A epoxy resin without any accelerating agent. ATBN weight percentage of 59–82 wt% was used, so that the soft ATBN domains in the cured samples formed a continuous phase, while the hard epoxy domains formed a discontinuous phase. Mechanical properties were tested in the means of strain-stress and adhesive strength. The results showed that the samples had excellent toughness at temperatures above the flexible segment glass transition temperature (Tg1), and it was well maintained after annealing at 150 °C. However, adhesive strength of the annealed sample decreased dramatically when the testing temperature was close to the rigid segment glass transition temperature (Tg2). It was observed that (Tg2) decreased and phase separation became weaker after the annealing. Real-time Fourier transform infrared (FTIR) measurement indicated that this phenomenon was related to the disassociation of hydrogen bonding within the hard domain caused by the increased mixing of the hard segments into the soft domains by the high temperature annealing. It was confirmed by transmission electronic microscope (TEM) test.

The investigation on the curing process of polysulfide sealant by in situ dielectric analysis

Co-reporter:Baijie Zhou;Dan He;Yiwu Quan

Journal of Applied Polymer Science 2012 Volume 126( Issue 5) pp:1725-1732

Publication Date(Web):

DOI:10.1002/app.36813

Abstract

In this work, in situ dielectric analysis (DEA) was employed for the first time to the best of our knowledge, to monitor the curing process of polysulfide (PSF) sealant using manganese dioxide (MnO₂) as the curing agent, where the gel point and ending point were determined. The obtained results were verified by rheological tests of dynamic mechanical analysis and tensile strength tests. It showed a significant difference between this curing process and those of usual thermosetting materials. The influences of the pH value of the samples and curing temperature were investigated and discussed in detail. Also, activation energies of the curing reaction of the samples with different pH values were calculated. The results proved DEA as a reliable and useful method for in situ monitoring PSF–MnO₂ curing process. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Improvement in compression performance of the polysulfide sealant by thiol-acrylate reaction

Co-reporter:Baijie Zhou;Junsheng Zhang;Qingjun Wang

Polymer Engineering & Science 2012 Volume 52( Issue 4) pp:912-919

Publication Date(Web):

DOI:10.1002/pen.22158

Abstract

Trimethylolpropanetriacrylate (TMPTA) was added to the polysulfide-manganese dioxide (PSF-MnO₂) liquid mixtures as a crosslinker to improve their crosslinking capability. The samples were cured at room temperature for different times and the crosslinking degree was characterized by extraction and swelling tests. Mechanical properties of the cured samples including tensile, compression (stress relaxation, permanent set, and cyclic compression), and dynamic mechanical behaviors were investigated. The results indicated that the TMPTA crosslinker significantly increased the crosslinking degree and the homogeneity of the formed PSF networks. As a result, the tensile and compression stress and relaxation performances of the cured PSF rubber were dramatically improved. This result was also consistent with the results from the swelling, cyclic compression, and dynamic mechanical measurements. Interestingly, the tensile strength of the TMPTA cured samples did not show apparent change when the curing time was longer than 14 days, whereas their compression stress and relaxation performance were growing remarkably from 14 to 60 days. The improved performances were attributed to the high efficiency of thiol-acrylate Michael addition reaction for the crosslinking. It promoted the curing rate, resulting in good compression properties in a much shorter curing time.POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers

Superhydrophobicity of Natural and Artificial Surfaces under Controlled Condensation Conditions

Co-reporter:Long Yin, Lin Zhu, Qingjun Wang, Jianfu Ding, and Qingmin Chen

ACS Applied Materials & Interfaces 2011 Volume 3(Issue 4) pp:1254

Publication Date(Web):March 28, 2011

DOI:10.1021/am200061t

In this paper, we have comparatively investigated the stability of superhydrophobic behaviors of fresh and biomimetic lotus leaf surfaces under controlled water condensation conditions. The binary micro/nano structures of the superhydrophobic surfaces are observed with electron micrographs. Contact and sliding angles are evaluated by syringing water droplets on the substrates with surface temperatures and humidity precisely controlled between −10 and 30 °C, and RH = 10, 30, 60, and 90%. According to the calculations on the solid−liquid contact area fraction in different environmental conditions based on a micro/nano binary structure model, the effects of condensed water on superhydrophobic surfaces are assessed quantitatively. Both the calculated and experimental results indicate that the temperature difference between surface temperature and the dew point during measurement is essential to the occurrence of water condensation while the effect of condensation on the surface wettability also depends on the topology of hierarchical structured surfaces. The loss of water repellency that usually appears on the artificial superhydrophobic surface under low temperature and high humidity conditions is proved to be reversible, showing a bidirectional transition of the equilibrium state between Wenzel and Cassie−Baxter.Keywords: condensation; contact angle; relative humidity; sliding angle; superhydrophobic; surface temperature

Kinetic study of polysulfide-acrylate click reaction by DEA and DMA

Co-reporter:Baijie Zhou;Mingxia Shen;Qingjun Wang

Polymers for Advanced Technologies 2011 Volume 22( Issue 12) pp:2374-2381

Publication Date(Web):

DOI:10.1002/pat.1773

Abstract

The curing process of a polysulfide (PSF) with a triacrylate crosslinker in the presence of an amine catalyst at room temperature is a rapid Michael addition. This reaction was monitored by real-time infrared spectrum (RTIR). The results of the RTIR show that the consumptions of thiol and acrylate are stoichiometric until 80% conversion, indicating the characteristics of a “click” reaction. Dielectric analyzer (DEA) and dynamic mechanical analyzer (DMA) were employed to investigate the curing kinetics from which the activation energies of this curing reaction were obtained and shown to correlate with each other. In addition, the influences of the types and amount of amine catalyst, the different molecular weights of PSFs, and the triacrylate crosslinkers were discussed. Copyright © 2011 John Wiley & Sons, Ltd.

A facile dip-coating process for preparing highly durable superhydrophobic surface with multi-scale structures on paint films

Co-reporter:Zhe Cui, Long Yin, Qingjun Wang, Jianfu Ding, Qingmin Chen

Journal of Colloid and Interface Science 2009 Volume 337(Issue 2) pp:531-537

Publication Date(Web):15 September 2009

DOI:10.1016/j.jcis.2009.05.061

Superhydrophobic surfaces with multi-scale nano/microstructures have been prepared on epoxy paint surfaces using a feasible dip-coating process. The microstructures with 5–10 μm protuberances were first prepared on epoxy paint surface by sandblast. Then the nanostructures were introduced on the microstructure surface by anchoring 50–100 nm SiO2 particles (nano-SiO2) onto the sandblasted paint surface, which was completed by dip-coating with a nano-SiO2/epoxy adhesive solution (M1). At last the surface was further modified for enhancing hydrophobicity by another dip-coating with a solution of a low surface energy polymer, aminopropyl terminated polydimethylsiloxane (ATPS) modified epoxy adhesive (M2). The water contact angle of the as-prepared samples reached as high as 167.8° and the sliding angle was 7°. The prepared superhydrophobic surface exhibited excellent durability to the high speed scouring test and high stability in neutral and basic aqueous solutions and some common organic solvents. In addition, this method can be adopted to fabricate large scale samples with a good homogeneity of the whole surface at very low cost.Superhydrophobic surfaces were created on an epoxy paint by sandblasting the paint surface to form microstructures (A), followed by anchoring nano-SiO2 on the microstructure surface to form multi-scale structures (B).

A moisture absorption and adhesion study of the process of blending film using p-alkylphenol-resorcinol-formaldehyde and rubber latex

Co-reporter:Mingxia Shen;Junsheng Zhang

Journal of Applied Polymer Science 2009 Volume 113( Issue 6) pp:3550-3556

Publication Date(Web):

DOI:10.1002/app.30291

Abstract

p-alkylphenol-resorcinol-formaldehyde-latex (ARFL) films were prepared by co-condensation of p-alkylphenols and resorcinol with formaldehyde to generate modified phenolic resins, followed by blending with rubber latex, aging, and finally curing. The weight-gain of the ARFL films and the tensile force of the coated fiberglass were studied under different temperatures and various humidities. The surfaces of the ARFL films were further analyzed by measuring the static contact angle and the findings were confirmed by Fourier Transform Infrared Spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis. The adhesion between the coated fiberglass and neoprene rubber was evaluated using the H-adhesion technique. The best hydrophobicity and the largest water contact angle were displayed on the surface of the p-nonylphenol-resorcinol-formaldehyde-latex (NRFL) film, with a weight-gain percent that was 40.0% (wt %) lower and a static contact angle that was 22.6° more than that of the resorcinol-formaldehyde-latex (RFL) film. The NRFL-coated fiberglass had a higher tensile force and H-adhesion force than the RFL-coated fiberglass. The shelf life of NRFL-coated fiberglass can be raised significantly at 40°C and under 98% humidity. The mechanism of the dramatic drop in the tensile force of the coated fiberglass is also discussed. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Preparation and characterization of fluorine-containing acrylate copolymers by 60Co γ-ray radiation co-polymerization

Co-reporter:Jun Li, Qingjun Wang, Changhong Su, Qingmin Chen

European Polymer Journal 2007 Volume 43(Issue 7) pp:2928-2934

Publication Date(Web):July 2007

DOI:10.1016/j.eurpolymj.2007.04.028

A series of fluorine-containing acrylate copolymers were prepared by 60Co γ-ray radiation co-polymerization in a mixed acrylate system, including butyl acrylate, acrylic acid, acrylonitrile, N-hydroxymethyl acrylamide and perfluoroalkylethyl methacrylate (FMA). The yield of the copolymers reached 96% when they were radiated for 34 h with the radiation dose of 1 kGy/h. Moreover, the surface structure and properties of the copolymers were determined by Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS) and contact angle (CA) analysis. And the glass-transition temperature was measured by dynamic mechanical thermal analysis (DMTA). It was found that the fluoropolymer was of large water static contact angle and fluorine was enriched at the polymer–air interface. The relationship between the copolymer composition, annealed temperature and static contact angle was also discussed in detail. Furthermore, when the FMA content reached 3%, the cotton treated with our products exhibited better oil repellency.

Modification of polysulfide sealant with polysulfide polythio-urethane-urea

Co-reporter:Yiwu Quan;Peng He;Baijie Zhou

Journal of Applied Polymer Science 2007 Volume 106(Issue 4) pp:2599-2604

Publication Date(Web):30 JUL 2007

DOI:10.1002/app.26792

With a small amount of isocyanate-terminated polysulfide (NCO-PSF-NCO) as additive, the commercial polysulfide-based sealant had significant improvement in mechanical properties. The test results showed that 5% of NCO-PSF-NCO could help to rise 50% in the tensile strength and 27% in the ultimate elongation of the polysulfide sealant. The adhesive strength to substrates such as steel, epoxy-coated or polyurethane-coated surface also increased significantly. Dynamic mechanical thermal analysis and differential scanning calorimetry analysis revealed that formed polysulfide polythio-urethane-urea (polysulfide-urea) contributed to a slight increase in the T_g of the polysulfide sealant. It might be due to the domains of polysulfide-urea, which had effects of physical crosslinking and chain-extending on the polysulfide sealant. However, the introduction of polysulfide-urea structures had no appreciable influence on oil resistance of the polysulfide sealant. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007

Synthesis of 4-vinyl benzyl tetra-coordinate silicate monomer

Co-reporter:Qinggang Kong;Xiaomo Zhang;Yiwu Quan

Polymer Bulletin 2007 Volume 59( Issue 2) pp:235-242

Publication Date(Web):2007 September

DOI:10.1007/s00289-007-0766-9

A new 4-vinyl benzyl tetra-coordinate silicate (VBTCS) was synthesized from a promising highly reactive penta-coordinate potassium glycolato silicate compound through a facile and one-step reaction. FT-IR, 1H NMR, 13C NMR and elemental analysis identified the structure of the 4-vinyl benzyl tetra-coordinate silicate. This new monomer was homopolymerized and copolymerized with styrene and butylmethacrylate, respectively. FT-IR, TG, DSC and GPC characterized polymers.

Preparation of super water-repellent membrane by radiation-induced copolymerization

Co-reporter:Wang Qingjun, Quan Yiwu, Zhang Junsheng, Chen Qingmin

Surface and Coatings Technology 2006 Volume 200(18–19) pp:5493-5497

Publication Date(Web):8 May 2006

DOI:10.1016/j.surfcoat.2005.07.069

Super water-repellent surfaces are generally introduced by controlling the surface chemistry and surface roughness, which are applied by means of complex time-consuming processes. We describe a simple method for forming super water-repellent surfaces using 60Coγ irradiation induced hexafluoropropylene/ethyl methacrylate (HFP/EMA) vapor phase copolymerization under atmospheric pressure conditions. The resulting coral-reef-like microtexture surface has a water contact angle of 153°. The method described here could easily be extended to preparing superhydrophobic surface from a wide variety of materials.

Ultraviolet curing of liquid polysulfide thiourethane acrylate

Co-reporter:Yi Wu Quan;Wen Zhao Dong;Jiang Ling Fang;Qing Min Chen

Journal of Applied Polymer Science 2004 Volume 91(Issue 4) pp:2358-2363

Publication Date(Web):15 DEC 2003

DOI:10.1002/app.13378

A series of liquid polysulfide thiourethane acrylate prepolymers were synthesized by the reaction of liquid polysulfide with isocyanate and hydroxyethyl acrylate. With and without a combination of acrylic monomers, the prepolymers were cured with ultraviolet radiation. The films exhibited a higher soft-segment glass-transition temperature than metal oxide cured polysulfide. With the addition of a diluent, the tensile strength and modulus increased, whereas the ultimate elongation decreased. The polysulfide backbone, combined with the crosslink generated from the photopolymerization of acrylic, produced films with superior oil resistance. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2358–2363, 2004

The structural and mechanical properties of polysulfide-based polyurea

Co-reporter:Wenzhao Dong;Yiwu Quan;Junsheng Zhang

Polymer International 2003 Volume 52(Issue 12) pp:

Publication Date(Web):8 OCT 2003

DOI:10.1002/pi.1301

A series of polysulfide-based polyureas was synthesized, which were based on isophorone diisocyanate (IPDI), liquid polysulfide and 2,5-diamino-3,6-dimethylmercaptotoluene (Ethacure-300). The structure and mechanical properties of these elastomers were investigated using dynamic mechanical thermal analysis, differential scanning calorimetry, stress–strain analysis, water-resistance and oil-resistance tests. The results showed that there was phase segregation between soft and hard segments in polysulfide-based polyurea. With the increase in number-average relative molar mass and content of liquid polysulfide, the tensile strength decreased while the ultimate elongation increased. The effect of number-average relative molar mass of polysulfide and hard-segment content on oil resistance is also discussed. Copyright © 2003 Society of Chemical Industry

Mechanical and surface properties of polysulfide-based polyurea modified with aminoethylaminopropyl poly(dimethylsiloxane)

Co-reporter:Yi Wu Quan;Jiang Ling Fang;Qing Min Chen;Qing Jun Wang

Journal of Applied Polymer Science 2003 Volume 87(Issue 4) pp:584-588

Publication Date(Web):18 NOV 2002

DOI:10.1002/app.11270

A series of polysulfide-based polyureas with different siloxane contents were synthesized, and they were based on isophorone diisocyanate, liquid polysulfide oligomer, aminoethylaminopropyl poly(dimethyl siloxane) (AEAPS), and 2,5-diamino-3,6-dimethylmercapto-toluene. The mechanical and surface properties were investigated with attenuated total reflectance Fourier transform infrared spectroscopy, surface contact angles, electron spectroscopy for chemical analysis, and stress–strain analysis. Siloxane was enriched on the surfaces of these elastomers, and the tensile properties of the elastomers did not change markedly with the AEAPS modification. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 584–588, 2003

Structure and oil-resistant properties of HTPB-based polyurea modified with polysulfide

Co-reporter:Qingjun Wang;Wenzhao Dong;Yiwu Quan

Journal of Applied Polymer Science 2003 Volume 89(Issue 10) pp:2672-2675

Publication Date(Web):18 JUN 2003

DOI:10.1002/app.12381

A series of hydroxy-terminated polybutadiene (HTPB) polyureas modified with different liquid polysulfide content was synthesized and their structure and oil-resistant properties were studied by attenuated total reflectance–FTIR spectroscopy, dynamic mechanical analysis, isothermal aging and differential scanning calorimetry, stress–strain analysis, oil absorption, and oil-resistance test. The results showed that polysulfide–polybutadiene polyureas retained low temperature flexibility and had lower oil absorption and better oil resistance than that of HTPB-based polyureas. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2672–2675, 2003

Influence of different chemical modifications on the icephobic properties of superhydrophobic surfaces in a condensate environment

Co-reporter:Yuanyi Wang, Mingzhen Li, Ting Lv, Qingjun Wang, Qingmin Chen and Jianfu Ding

Journal of Materials Chemistry A 2015 - vol. 3(Issue 9) pp:NaN4975-4975

Publication Date(Web):2015/01/16

DOI:10.1039/C4TA07077A