Fabrication of teardrop-shaped silica particles in polyelectrolyte diluted solution through in situ sol–gel process

Spherical silica particles, with mean sizes about 1.2 μm, were prepared through TEOS sol-gel process catalyzed by ammonia. The silica particles have a smooth surface and a small specific surface area, 3.4 m2/g. The sol-gel process was monitored by React IRTMusing an in-situ technique. Based on the measurements, mechanism of TEOS hydrolyzation and succedent condensation polymerization was inferred. With the adding of ammonia, OH-anion attacks Si atomic nucleus directly and makes it showing negative electricity. Therefore the electron cloud shifts to the OR group on the other side. This weakens the Si-O bond and results in the removal of the OR group. Furthermore, silanol, generated from TEOS hydrolyzation, attracts Si-OR or other Si-OH around; thereby resulting rapid dehydration or dealcohol between molecular. So the condensation polymerization rate is elevated, and Si-O-Si bond comes into being. Lastly, cross-linking reaction among Si-O-Si bonds forms the particle.

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Synthesis and Intermolecularly Mediated Assembly of Organic Pigment in Hybrid Coating Films

MRS Proceedings ◽

10.1557/proc-519-103 ◽

1998 ◽

Vol 519 ◽

Author(s):

Y. Yan ◽

Z. Duan ◽

D.-G. Chen ◽

S. Ray Chaudhuri

Keyword(s):

Sol Gel ◽

Hybrid Coating ◽

Hypsochromic Shift ◽

Hybrid Films ◽

Coating Films ◽

Organic Pigment ◽

Inorganic Hybrid ◽

Matrix Interactions ◽

Sol Gel Process

AbstractThe insoluble, strongly hydrogen bonded organic pigment of 3,6-bis-(4-chlorphenyl)-l,4- diketopyrrolo [3,4-c] pyrrole was transiently blocked by adding carbamate groups, and consequently incorporated into organic-inorganic hybrid matrices by a sol-gel process. The homo- (pigment-pigment) and hetero-intermolecular (pigment-matrix) interactions were found to control both the assembly and dispersion of pigment molecules in the hybrid coating films. A weaker interaction between matrices and pigment molecules results in aggregation of the carbamate pigment in the methyl-silicate films. A stronger interaction forms a homogenous dispersion and coloration of the phenyl-silicate films. The as-prepared methyl- and phenylsilicate films doped with the organic pigment were distinguished by a morphology change and a blue (hypsochromic) shift in absorption from 550 to 460 nm. Thermal treatment can remove the carbamate groups and in-situ form the organic pigment in the hybrid films.

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Ultrahigh Surface Area Nanoporous Silica Particles via an Aero-Sol−Gel Process

Langmuir ◽

10.1021/la034864k ◽

2004 ◽

Vol 20 (7) ◽

pp. 2523-2526 ◽

Cited By ~ 42

Author(s):

S. H. Kim ◽

B. Y. H. Liu ◽

M. R. Zachariah

Keyword(s):

Surface Area ◽

Sol Gel ◽

Silica Particles ◽

Nanoporous Silica ◽

Sol Gel Process

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Control of Hierarchically Ordered Positive and Negative Replicas of Wood Cellular Structures by Surfactant-Directed Sol-Gel Mineralization

MRS Proceedings ◽

10.1557/proc-726-q5.4 ◽

2002 ◽

Vol 726 ◽

Author(s):

Yongsoon Shin ◽

Jun Liu ◽

Li-Qiong Wang ◽

Jeong Ho Chang ◽

William D. Samuels ◽

...

Keyword(s):

Silicic Acid ◽

Cell Walls ◽

Cellular Structure ◽

Sol Gel ◽

Ceramic Materials ◽

Silica Particles ◽

Low Ph ◽

Cellular Structures ◽

Inner Surface

AbstractWe here report the synthesis of ordered ceramic materials with hierarchy produced by an in-situ mineralization of ordered wood cellular structures with surfactant-templated sol-gel at different pH. At low pH, a silicic acid is coated onto inner surface of wood cellular structure and it penetrates into pores left, where degraded lignin and hemicellulose are leached out, to form a positive replica, while at high pH the precipitating silica particles due to fast condensation clog the cells and pit structures to form a negative replica of wood. The calcined monoliths produced in different pHs contain ordered wood cellular structures, multi-layered cell walls, pits, vessels well-preserved with positive or negative contrasts, respectively. The surfactant-templated mineralization produces ordered hexagonal nanopores with 20Å in the cell walls after calcination.

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Microporous Silica Particles Prepared by the Salt-Catalytic Sol-Gel Process with Extremely Low Content of Water

Journal of Sol-Gel Science and Technology ◽

10.1023/b:jsst.0000016133.24903.ff ◽

2004 ◽

Vol 29 (1) ◽

pp. 19-24 ◽

Cited By ~ 4

Author(s):

Yasushi Murakami ◽

Kazuhiko Tanaka ◽

Yusuke Takechi ◽

Saki Takahashi ◽

Yuuki Nakano ◽

...

Keyword(s):

Sol Gel ◽

Silica Particles ◽

Microporous Silica ◽

Sol Gel Process

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Fabrication of sulfonated poly(ether ether ketone)-based hybrid proton-conducting membranes containing carboxyl or amino acid-functionalized titania by in situ sol–gel process

Journal of Power Sources ◽

10.1016/j.jpowsour.2014.11.132 ◽

2015 ◽

Vol 276 ◽

pp. 271-278 ◽

Cited By ~ 50

Author(s):

Yongheng Yin ◽

Tao Xu ◽

Guangwei He ◽

Zhongyi Jiang ◽

Hong Wu

Keyword(s):

Amino Acid ◽

Sol Gel ◽

Proton Conducting ◽

Ether Ether Ketone ◽

Poly Ether Ether Ketone ◽

Sol Gel Process ◽

Ether Ketone ◽

Conducting Membranes ◽

Sulfonated Poly

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Preparation of the polymerizable titania oriented to 3D printing and the laser-induced crystallization

Rapid Prototyping Journal ◽

10.1108/rpj-03-2017-0041 ◽

2018 ◽

Vol 24 (9) ◽

pp. 1421-1427 ◽

Cited By ~ 2

Author(s):

Feng Liu ◽

Shaoai Xie ◽

Yan Wang ◽

Jianjun Yu ◽

Qinghua Meng

Keyword(s):

3D Printing ◽

Sol Gel ◽

Crystal Form ◽

Tetrabutyl Titanate ◽

Content Type ◽

Functional Additives ◽

Sol Gel Process ◽

Photosensitive Resin ◽

Induced Crystallization

PurposeThe titania (titanium dioxide) is one of the important functional additives in the photosensitive resin and encounters the problem of stabilization in the photosensitive resin for 3D printing. This study aims to achieve enhancement in stabilization by preparation of the polymerizable titania andin situlaser-induced crystallization during 3D printing.Design/methodology/approachA type of polymerizable titania (AAEM@TiO2) was designed and prepared from tetrabutyl titanate (TBT) and 2-(acetoacetoxy)ethyl methacrylate (AAEM) via the sol–gel process, which was characterized by Fourier-transform infrared (FTIR) spectra, ultraviolet–visible (UV-Vis) spectra, surface bonding efficiency (SBE) and settling height (H). AAEM acted on both bonding to the titania and polymerization with the monomer in resin for stabilization. The polymerizable titania could be converted to the pigmented titania by means of laser-induced crystallization. The photosensitive resin was then formulated on the basis of optimization and used in a stereolithography apparatus (SLA) for 3D printing.FindingsThe stabilization effect of AAEM on TiO2was achieved and the mechanism of competition in the light-consuming reactions during photocuring was proposed. The ratio of nAAEM/nTBTin AAEM@TiO2, the concentration of AAEM@TiO2and photoinitiator (PI) used in the photosensitive resin were optimized. The anatase crystal form was indicated by X-ray diffraction (XRD) and clustering of nanocrystals was revealed by scanning electron microscopy (SEM) after SLA 3D printing.Originality/valueThis investigation provides a novel method of pigmentation by preparation of the polymerizable titania andin situlaser-induced crystallization for SLA 3D printing.

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