Preparation and Characterization of Surface-Modified β-Tricalcium Phosphate/Ploy(L-Lactide) Biocomposites

A new surface modification method by modifying low molecular weight ploy (L-lactide) (LMW PLLA) onto the β-tricalcium phosphate (β-TCP) superfine particles has been developed. The surface-modified β-TCP is characterized by FT-IR, XRD, digital microscope and contact angle measurement, et al. FT-IR spectra confirmed that LMW PLLA was connected onto the β-TCP surface through ionic interaction. XRD results indicated that the LMW PLLA did not affect the crystalline form of β-TCP, but the XRD patterns of the p-β-TCP showed a little difference with β-TCP. The p-β-TCP particles could be dispersed uniformly in dichloromethane. In contrast, unmodified β-TCP particles are apt to agglomerate after dispersed into dichloromethane. Wet angle measurement showed that hydrolyzed LMW PLLA significantly improves hydrophobicity of modified β-TCP particles. For the preparation of composites, PLLA was mixed with β-TCP and p-β-TCP, respectively, in a ratio of 85/15 (w/w) and moulded into tensile test specimens. Tensile tests showed that mechanical properties were improved, scanning electron microscopy (SEM) exhibited that modified β-TCP is an effective approach to prepare a homogeneous composites, moreover, it indicated a better interfacial phase interaction in the composite with the p-β-TCP. Chemical bonds between filler and PLLA matrix are assumed to be formed by ionic interaction.

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Synthesis and characterization of the polyacrylate latex functionalized by fluorine and silicon

e-Polymers ◽

10.1515/epoly.2007.7.1.554 ◽

2007 ◽

Vol 7 (1) ◽

Author(s):

Xiaofeng Ding ◽

Rong Guan ◽

Peizhi Chen

Keyword(s):

Surface Energy ◽

Water Resistance ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Latex Films ◽

Water Contact ◽

Energy Estimation ◽

Ratio Measurement ◽

Ft Ir

AbstractNovel functionalized polyacrylate latex with fluorine and silicon was prepared by semi-continuous dropping technique. 19F NMR, elemental analysis of the silicon (EAS) and FT-IR measurements prove that 2,2,2-trifluoroethyl methacrylate (TFEMA) and α,ω-bis(hydroxyl)polydimethylsiloxane (PDMSH) is successfully polymerized. TEM demonstrates that the functionalized latex particles were spherical, uniform and stable. Contact angle measurement and surface energy estimation show that the highest water contact of the functionalized latex films were 118.3° and the surface energy was as low as 11.7 mJ/m2. Water absorption ratio measurement reveals that the water resistance of the functionalized latex films is improved. The heat resistance of the functionalized latex films does not show a large difference from that of the original polyacrylate in our investigated systems.

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Surface Chemical Modification and Characterization of Nano Fe2O3

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.345.180 ◽

2013 ◽

Vol 345 ◽

pp. 180-183

Author(s):

Yan Liu ◽

He Yi Ge ◽

Xiu Zhi Zhang ◽

Shi Feng Huang ◽

Xin Cheng

Keyword(s):

Contact Angle ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Organic Polymer ◽

X Ray Diffraction ◽

The Matrix ◽

Ft Ir ◽

Acidic Conditions ◽

Surface Chemical Modification

The surface of nanoFe2O3 was modified with silane coupling agent 3-(methacryloyloxy) propyltrimethoxysilane (KH-570) under acidic conditions in order to improve the dispersity of particles in organic polymer and to enhance the interfacial bonding with the matrix. Contact angle measurement, thermogravimetric analysis (TG), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) were adopted to characterize and analyze the unmodified and modified nanoFe2O3. Through TG curves, it was calculated that when the KH-570 content was 25%, the grafting rate of Fe2O3 reached a maximum value at 7.28%. The FT-IR and XRD results indicated that KH-570 successfully modified the nanoFe2O3 with its organic functional groups chemically bonded on the surface of nanoFe2O3 which contributed to prevent particles from conglomerating. The surface treatment of nanoFe2O3 had no significant effect on the nanoparticles crystalline form. Contact angle measurement investigated that the hydrophile of modified nanoFe2O3 was decreased.

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The effect of molecular assembly between collectors and inhibitors on the flotation of pyrite and talc

Royal Society Open Science ◽

10.1098/rsos.191133 ◽

2019 ◽

Vol 6 (10) ◽

pp. 191133 ◽

Cited By ~ 2

Author(s):

Tao Long ◽

Wei Xiao ◽

Wei Yang

Keyword(s):

Copper Sulfide ◽

Guar Gum ◽

Magnesium Silicate ◽

Selective Inhibition ◽

Contact Angle Measurement ◽

Molecular Assembly ◽

Angle Measurement ◽

Pyrite Surface ◽

Flotation Process ◽

Ft Ir

In the flotation process, the traditional dosing sequence is to add an inhibitor first, followed by a collector. However, in the sorting process of copper sulfide ore, this method of dosing does not effectively separate sulfide minerals and layered magnesium silicate minerals. In this study, the effect of adding a guar gum (as an inhibitor) and potassium amyl xanthate (as a collector, shortened as PAX) sequence to the flotation separation of pyrite and talc was investigated by micro-flotation tests, adsorption amount measurements, contact angle measurement and FT-IR analysis. The results show that the collector only adsorbs on the pyrite surface, while the inhibitor has a strong adsorption capacity on the pyrite and talc surface. Through the change of the order of the flotation reagent addition, PAX preferentially adsorbs on the pyrite surface, thereby preventing guar gum from adsorbing on the pyrite surface and achieving the selective inhibition of talc by guar gum. This study will help in understanding the molecular assembly between collectors and inhibitors to further treat complex copper sulfide nickel ore.

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Synthesis and Characterization of Ag/Graphene Nanocomposites by Solid-Liquid Sonochemical Reactions

Materials Science Forum ◽

10.4028/www.scientific.net/msf.804.119 ◽

2014 ◽

Vol 804 ◽

pp. 119-122 ◽

Cited By ~ 1

Author(s):

Tomofumi Mochizuki ◽

Yamato Hayashi ◽

Jun Fukushima ◽

Hirotsugu Takizawa

Keyword(s):

Silver Oxide ◽

Graphene Nanocomposites ◽

Hummers Method ◽

Ft Ir ◽

Physical Effects ◽

Diffraction Patterns ◽

Xrd Patterns ◽

Short Time ◽

Solid Liquid

In this study, Graphite Oxide (GO) and Ag/Graphene nanocomposites were synthesized by solid-liquid sonochemical reactions easily and briefly. GO was synthesized by means of Hummers method using sonication or stirring. From XRD patterns and FT-IR spectra, chemical and physical effects of ultrasound promoted the oxidation of Graphite. Ag/graphene nanocomposites were synthesized from GO and silver oxide by sonication. UV-vis spectra showed the peaks of Graphene oxide and Ag nanoparticle plasmon resonance absorption. EDX images and electron diffraction patterns confirmed Ag nanoparticles were decorated on Graphene sheets by ultrasound. Using sonication, GO and Ag/Graphene nanocomposites could be synthesized easily in short time.

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Physicochemical characterization of actinomycetes isolated from decayed cedar wood: contact angle measurement

Journal of Adhesion Science and Technology ◽

10.1080/01694243.2014.943341 ◽

2014 ◽

Vol 28 (20) ◽

pp. 2046-2053 ◽

Cited By ~ 3

Author(s):

Hajar Maataoui ◽

Hassan Barkai ◽

Moulay Sadiki ◽

Abdellatif Haggoud ◽

Saad Ibnsouda Koraichi ◽

...

Keyword(s):

Contact Angle ◽

Physicochemical Characterization ◽

Contact Angle Measurement ◽

Angle Measurement

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SYNTHESIS AND CHARACTERIZATION OF SUPERHYDROPHOBIC ZnO HIERARCHICAL STRUCTURES

NANO ◽

10.1142/s1793292011002500 ◽

2011 ◽

Vol 06 (03) ◽

pp. 265-269 ◽

Cited By ~ 1

Author(s):

QUNBING ZHANG ◽

SHIHE CAO ◽

JUN WANG

Keyword(s):

Contact Angle ◽

Hydrothermal Process ◽

Hierarchical Structures ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Zno Films ◽

Water Contact ◽

Simple Method ◽

Microscopy Images

ZnO films with well-aligned hierarchical structures have been successfully synthesized at moderate temperatures using a simple catalyst-free hydrothermal process. The synthesized ZnO films are found to be single-phase, with a hexagonal wurtzite-type structure. Scanning electron microscopy images show that the well-aligned hierarchical structures are assembled with interlaced parallel sheets grown on the (400) silica surface. The water contact angle measurement indicates that the water on the films has a contact angle of about 156.3°. This clearly demonstrates that the ZnO films synthesized by this simple method have superhydrophobic properties and may be important for applications in self-cleaning surfaces, biology, and so on.

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Preparation and Characterization of Polystyrene/TiO2 Core-Shell Nanospheres via Suspension Technique

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.829.120 ◽

2013 ◽

Vol 829 ◽

pp. 120-125

Author(s):

Mona Shahshojaei ◽

Hossein Behniafar ◽

Masoud Shaabanzadeh

Keyword(s):

Deionized Water ◽

Poly Vinyl Alcohol ◽

Core Shell ◽

Nanosized Particle ◽

Sem Images ◽

Modification Factor ◽

Ft Ir ◽

Surface Modified ◽

Ultrasonic Homogenizer

In the present work, at first, nanoTiO2particles in anatase form were effectively surface modified via reacting with NCO groups of 4,4-methylenediphenyl disocyanate (MDI). Secondly, a solution of azobisisobutyronitrile (AIBN) (0.1 g) in inhibitor-free styrene (10 g) was poured into a 150 mL flask containing poly (vinyl alcohol) (PVA) suspending agent (0.1 g) in deionized water (60 mL) under N2flow, while stirring. The reaction mixture was then heated to 80 °C, and stirred for another 1 h. Next, it was divided to two portions; one for the synthesis of pure PS, and the other for the synthesis of PS/TiO2nanocomposites. Each aqueous portion was individually mixed with dichloromethane in a separating funnel. For PS/TiO2nanocomposites, the organic phase was charged with nanoTiO2particles (MDI-treated and/or untreated) (0.05 g), and then fully homogenized using ultrasonic homogenizer. Methanol non solvent was eventually used to precipitate the products. All samples involving pure PS, PS/surface modified TiO2nanocomposite, and PS/surface unmodified TiO2nanocomposite were thoroughly washed, filtered, and dried in vacuum at 50 °C for 12 h. From SEM images a core-shell relation could be clearly detected between the nanoTiO2particles and PS matrix. Meanwhile, the surface modified TiO2was dispersed into the PS matrix with better homogeneity compared to that of unmodified one. Undoubtedly, beside the surface modification factor, PVA suspending agent as an effective nanosized particle stabilizer, too, played a basic role in this high homogeneity. Also, FT-IR and XRD analyses led to promising results.

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Characterization of Lipid Membrane Properties for Tunable Electroporation

ASME 2012 Third International Conference on Micro/Nanoscale Heat and Mass Transfer ◽

10.1115/mnhmt2012-75321 ◽

2012 ◽

Author(s):

H. Jeremy Cho ◽

Shalabh C. Maroo ◽

Evelyn N. Wang

Keyword(s):

Lipid Bilayers ◽

Lipid Membrane ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Membrane Properties ◽

Force Microscopy ◽

Packing Structure ◽

Atomic Force ◽

Dynamics Simulations

Lipid bilayers form nanopores on the application of an electric field. This process of electroporation can be utilized in different applications ranging from targeted drug delivery in cells to nano-gating membrane for engineering applications. However, the ease of electroporation is dependent on the surface energy of the lipid layers and thus directly related to the packing structure of the lipid molecules. 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) lipid monolayers were deposited on a mica substrate using the Langmuir-Blodgett (LB) technique at different packing densities and analyzed using atomic force microscopy (AFM). The wetting behavior of these monolayers was investigated by contact angle measurement and molecular dynamics simulations. It was found that an equilibrium packing density of liquid-condensed (LC) phase DPPC likely exists and that water molecules can penetrate the monolayer displacing the lipid molecules. The surface tension of the monolayer in air and water was obtained along with its breakthrough force.

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Preparation and Characterization of Fluoroalkyl Methacrylate Copolymer Emulsion Using in Glass Fiber

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.580.548 ◽

2012 ◽

Vol 580 ◽

pp. 548-551

Author(s):

Yi Ming Sun ◽

Xia Xie ◽

Xu Huang Chen ◽

Yan Lin Chen

Keyword(s):

Glass Fiber ◽

Contact Angle Measurement ◽

Angle Measurement ◽

Copolymer Film ◽

Latex Film ◽

Hydrophobic Property ◽

Particle Size Analyzer ◽

The Stability ◽

Methacrylate Copolymer

Copolymer emulsions containing fluorine were prepared by emulsion polymerization with MMA, BA and G06B using SDBS as emulsifier. The copolymer was characterized by FTIR and DSC. The size and distribution of the latex particle in emulsion were obtained by particle size analyzer. The stability of emulsion was observed and the solvent resistance of latex films was investigated. Surface properties of the copolymer film were investigated by contact angle measurement. The results showed that adding fluorine group to copolymer could increase hydrophobic property of the latex film and decrease the surface free energy of copolymer film. Glass fiber will have excellent properties when combining with the copolymer emulsion.

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