Chlorination Treatment of Meta-Aramid Fibrids and Its Effects on Mechanical Properties of Polytetramethylene Ether Glycol/Toluene Diisocyanate (PTMEG/TDI)-Based Polyurethane Composites

Meta-aramid fibrids (MAF) have attracted much attention. However, it is difficult for this high mechanical performance fiber to form sufficient interface adhesion between the MAF and polyurethane (PU) matrix due to the chemical inertness of its surface. Thus, the surface activity of MAF should be improved to obtain a high-performance MAF/PU composite. A novel methodology to modify the surface of MAF with a sodium dichloroisocyanurate solution (DCCNa) was developed to obtain chlorinated MAF (MAFC) in this study. A series of MAFC/PU composites was prepared by in situ polymerization processes. The results of Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) demonstrated that the chlorine-contained chemical groups were introduced onto the MAF surfaces after chlorination. Dynamic contact angle analysis (DCAA) revealed that the surface wettability and the surface free energy of the MAFC were significantly improved, which allowed for strong chemical bonding to PU. Scanning electron microscopy (SEM) showed a uniform distribution of MAFC and good interfacing bonding between the MAFC and PU. With the incorporation of 1.5 wt% MAFC into the polyurethane matrix, the tensile and tear strength values of MAFC/PU were 36.4 MPa and 80.1 kN·m−1 respectively, corresponding to improvements of approximately 43.3% and 21.1%, as compared to those of virgin PU as 25.4 MPa and 66.1 kN·m−1, respectively.

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Effects of grafting low-generation poly(amido amine) onto carbon fiber surface by in situ polymerization on the mechanical properties of fiber composites

High Performance Polymers ◽

10.1177/0954008316658534 ◽

2016 ◽

Vol 29 (7) ◽

pp. 808-815 ◽

Cited By ~ 2

Author(s):

Bo Gao ◽

Wentao Du ◽

Qinghai Ma ◽

Ruliang Zhang ◽

Chengguo Wang ◽

...

Keyword(s):

Mechanical Properties ◽

Photoelectron Spectroscopy ◽

In Situ Polymerization ◽

Dynamic Contact Angle ◽

Fiber Surface ◽

Dynamic Contact ◽

Fiber Composites ◽

Force Microscopy ◽

Hybrid Reinforcement

Low-generation poly(amido amine) (PAMAM)-grafted carbon fibers (CFs) emerged as a new reinforcement for improving the mechanical properties of fiber composites. In this work, hybrid reinforcement, which could greatly enhance the surface roughness and wettability of CF, was prepared via growing PAMAM onto fiber surface by in situ polymerization.The modified surface morphology and chemical composition were investigated by scanning electron microscopy, atomic force microscopy, dynamic contact angle analysis test, and X-ray photoelectron spectroscopy. Experimental results indicated PAMAM dendrimers grown on the CF significantly enhanced interfacial properties of the resulting composites. In addition, compared with the desized CF composites, the CF grafted with PAMAM composites exhibited 34.65% enhancement in the interfacial shear strength.

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Influence of Acid-Treated Carbon Nano-Tubes on the Microstructure and Properties of Carbon Nano-Tubes Polyurethane Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.146-147.805 ◽

2010 ◽

Vol 146-147 ◽

pp. 805-809

Author(s):

Ji You Gu ◽

Lan Zhang ◽

Xian Kai Jiang

Keyword(s):

Photoelectron Spectroscopy ◽

Acid Treatment ◽

In Situ Polymerization ◽

Mechanical Analysis ◽

X Ray ◽

Carbon Nano Tubes ◽

Dynamic Storage ◽

Treated Carbon ◽

Polyurethane Composites

The investigations including the acid treatment to multi-walled carbon nano-tubes (MWNTs) and the synthesis of MWNTs/polyurethane composites via in situ polymerization were done. X-ray Photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and dynamic mechanical analysis (DMA) were utilized for evaluating the effects of acid-treated MWNTs on the properties and microstructure of the composites. The results indicated that carboxyl groups could be successfully introduced onto the surface of MWNTs by acid treatment. The dynamic storage modulus and glass transition temperature of composites increased with the existence of MWNTs. The improvement of polyurethane by acid-treated MWNTs performed better compared to raw MWNTs.

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Effect of Plasticizer of Sizing Agent on the Surface of Carbon Fibers and Interface of its Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.337.10 ◽

2011 ◽

Vol 337 ◽

pp. 10-15 ◽

Cited By ~ 1

Author(s):

Huan Xia Zhang ◽

Amin Cao ◽

Yong Kang Luo ◽

Li Wei

Keyword(s):

Contact Angle ◽

Carbon Fibers ◽

Photoelectron Spectroscopy ◽

Interfacial Shear Strength ◽

Dynamic Contact Angle ◽

Dynamic Contact ◽

Interfacial Shear ◽

X Ray ◽

Physical Changes ◽

Contact Angle Analysis

In this work, carbon fibers were sized with different plasticizer of sizing agent in order to improve the performances of carbon fibers and the interface of carbon fibers composites. The chemical and physical changes induced by the treatments on carbon fibers surface are examined using dynamic contact angle analysis test(DCAT) , X-ray photoelectron spectroscopy (XPS). The interfacial shear strength (IFSS) of CF/EP composites are analysised by micro-droplet test. At the same time, the wear resistance was also studied in order to understand the effect of the plasticizer of sizing agent on the carbon fibers. The study shows that the 3# sized carbon fiber has the better wetting and surface energy. XPS results reveal that the 3# samples show a significant increase in oxygen-containing groups, such as–C–OH, -COOH, -C–O–C- and -COOR. 3#sizing agent also show better interface adhesion between fibers and matrix and has better wear resistant properties.

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Enhanced interfacial adhesion of UHMWPE fibers by alkali treatment and its behavior to PI resins

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705717743296 ◽

2017 ◽

Vol 32 (1) ◽

pp. 52-61 ◽

Cited By ~ 2

Author(s):

Gang Tang ◽

Xiong Hu ◽

Tianhao Tang ◽

Christophe Claramunt ◽

Chengliang Liu

Keyword(s):

Photoelectron Spectroscopy ◽

Interfacial Adhesion ◽

Alkali Treatment ◽

Dynamic Contact Angle ◽

Dynamic Contact ◽

Strength Analysis ◽

Uhmwpe Fiber ◽

Wetting Ability ◽

Uhmwpe Fibers ◽

Interlaminar Shear

The effect of alkali treatment on the UHMWPE fiber and interface of its composites was evaluated by atomic force microscopy, X-ray photoelectron spectroscopy, single-fiber tensile strength analysis, and dynamic contact angle analysis. The objective of this work is to improve the interlaminar shear strength of the composites by mixing the PI resin and modifying the UHMWPE fibers. Surface analysis showed that after treatment, the surface roughness and the wetting ability of UHMWPE fiber were increased. Results indicated that the alkali treatment plays a more important role in improving the surface property and interfacial adhesion of UHMWPE fibers’ composites.

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Development, Investigation, and Comparative Study of the Effects of Various Metal Oxides on Optical Electrochemical Properties Using a Doped PANI Matrix

Polymers ◽

10.3390/polym13193344 ◽

2021 ◽

Vol 13 (19) ◽

pp. 3344

Author(s):

Amina Bekhoukh ◽

Imane Moulefera ◽

Lilia Sabantina ◽

Abdelghani Benyoucef

Keyword(s):

Comparative Study ◽

Electrochemical Properties ◽

Photoelectron Spectroscopy ◽

High Performance ◽

In Situ Polymerization ◽

Polymeric Matrix ◽

Hybrid Nanocomposites ◽

X Ray ◽

Vis Spectroscopy ◽

Pani Matrix

A comparative study was performed in order to analyze the effect of metal oxide (MO) on the properties of a polymeric matrix. In this study, polyaniline (PANI)@Al2O3, PANI@TiC, and PANI@TiO2 nanocomposites were synthesized using in situ polymerization with ammonium persulfate as an oxidant. The prepared materials were characterized by various analytical methods such as X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), UV/visible (UV/Vis) spectroscopy, Fourier-transform infrared spectroscopy (FTIR), and transmission electron microscopy (TEM). Furthermore, the conductive properties of the materials were tested using the four-point probe method. The presence of MO in the final product was confirmed by XPS, XRD, FTIR, and TEM, while spectroscopic characterization revealed interactions between the MOs and PANI. The results showed that the thermal stability was improved when the MO was incorporated into the polymeric matrix. Moreover, the results revealed that incorporating TiO2 into the PANI matrix improves the optical bandgap of the nanocomposite and decreases electrical conductivity compared to other conducting materials. Furthermore, the electrochemical properties of the hybrid nanocomposites were tested by cyclic voltammetry (CV) and galvanostatic charge/discharge (GCD). The obtained results suggest that the PANI@TiO2 nanocomposite could be a promising electrode material candidate for high-performance supercapacitor applications.

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Adsorption of Hyperbranched Polysiloxysilane Modified with Triethoxy Group onto the Silicon Wafer

High Performance Polymers ◽

10.1177/0954008307081213 ◽

2007 ◽

Vol 19 (5-6) ◽

pp. 700-710 ◽

Cited By ~ 3

Author(s):

Yasuko Yamada ◽

Tomoyasu Hirai ◽

Ryohei Kikuchi ◽

Teruaki Hayakawa ◽

Masa-Aki Kakimoto

Keyword(s):

Contact Angle ◽

Silicon Wafer ◽

Photoelectron Spectroscopy ◽

Dynamic Contact Angle ◽

Dynamic Contact ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Wafer Surface ◽

Water Contact ◽

Silicon Wafer Surface

Triethoxysilyl functionalized hyperbranched polsiloxysilanes at the focal (FT-HBPSs) and terminal (TT-HBPSs) positions were synthesized to investigate adsorption behavior onto a silicon wafer surface. The surface of the silicon wafer adsorbed with the HBPSs was characterized by X-ray photoelectron spectroscopy, atomic force microscopy (AFM), static and dynamic water contact angle measurements. The AFM images indicated the formation size of dot-like structures were approximately 200 nm. The presence of vinyl terminal groups of FT-HBPSs permitted conversion of the surface from a non-polar hydrocarbon to a polar hydroxylated or carboxylated structures. After the polarity was changed, the surface properties were also studied using the above surface analysis techniques. The dynamic contact angle measurement indicated that the silicon wafer surface modified by FT-HBPSs was more hydrophilic in water than TT-HBPS. This behavior can be explained by the difference of connecting points between HBPS and the silicon wafer surface.

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Description of Dynamic Contact Angle on a Rough Solid Surface

Heat Transfer: Volume 3 ◽

10.1115/ht2003-47470 ◽

2003 ◽

Author(s):

X. F. Peng ◽

X. D. Wang ◽

D. J. Lee

Keyword(s):

Contact Angle ◽

Solid Surface ◽

Contact Line ◽

Mechanical Performance ◽

Solid Wall ◽

Dynamic Contact Angle ◽

Intrinsic Property ◽

Dynamic Contact ◽

Characteristic Parameter ◽

Precursor Film

An investigation was conducted to understand the contact line movement and associated contact angle phenomena. Contact line was supposed to move on a thin precursor film caused by molecular interaction between solid and liquid and asperity of solid surface. It is expected that contact line has a velocity and is subject to viscous stress on the film or geometrically on the solid surface. With the introduction of a characteristic parameter, λ′, the movement of contact line and contact angle phenomena were very well described in both physics and mathematics. The viscous shearing stress exerted by liquid on solid surface was derived, and the behavior of dynamic contact angle was recognized on rough solid surfaces. The analyses indicate that characteristic parameter, λ′, is dependent upon solid wall intrinsic property and mechanical performance, not liquid property. The comparison of theoretical predictions with available experimental data in open literature showed a quite good agreement with each other.

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