Nanostructured Surface Coating Layer of Calcium Carbonate Composite Particles

2007 ◽  
Vol 280-283 ◽  
pp. 593-596 ◽  
Author(s):  
S.M. Fan ◽  
Guo Sheng Gai ◽  
Yu Fen Yang ◽  
Shao Yun Fu ◽  
He Zhuo Miao
Keyword(s):  
Calcium Carbonate ◽  
Heterogeneous Nucleation ◽  
Surface Coating ◽  
Coating Layer ◽  
Physical Adsorption ◽  
Composite Particles ◽  
Nanostructured Surface ◽  
Compact Structure ◽  
The Core ◽  
Carbonate Particle

The calcium carbonate composite particles with nanostructured surface were prepared by heterogeneous nucleation. The calcium carbonate composite particles consisted of a core of groundcalcium carbonate particle and a shell of nanometer calcium carbonate particles. The thickness of theshell of composite calcium carbonate was observed by TEM. The bond intensity between the core and the shell was measured by means of ultrasonic comminution and stirred ball milling. It was found that the composite calcium carbonate had a compact structure. The linkage between the core and shell was so strong that it must be chemical bond instead of physical adsorption.

Influence of the Coating Layer Characteristics on the Dynamic Permeability and Printing of Ink-Jet Paper

2015 ◽  
Vol 731 ◽  
pp. 447-451
Author(s):  
Zheng Jian Zhang ◽  
Ji Hui Xin ◽  
Li Ying Yang ◽  
Bo Tao Liu
Keyword(s):  
Calcium Carbonate ◽  
Polyvinyl Alcohol ◽  
Surface Coating ◽  
Coating Layer ◽  
Single Layer ◽  
Hole Diameter ◽  
Precipitated Calcium Carbonate ◽  
Dynamic Permeability ◽  
Ink Jet ◽  
Color Density

In order to investigate the influence of coating layer characteristics on the dynamic permeability and printing of ink-jet paper, coating was prepared by the precipitated calcium carbonate (PCC) and white latex used as bottom coating (recipe label:A,B),and coating formula was made by silica (SiO2) and polyvinyl alcohol used as surface coating (recipe label:a,b,c).Then paper were coated respectively on single bottom, single surface and multilayer. Then the dynamic permeability and printing of ink-jet paper were analyzed systematically. The results showed that whether single layer or multilayer, the values of Ct, Ci were minimum when the ration of pigment and adhesive was 70:30, because the hole diameter of the coating layer was smallest, and the absorption was strongest, so the dynamic permeability was best, and the ability of ink absorption was best, color density and tone reproducibility were best. It concluded that when the proportion of SiO2 and PVA was 70:30, the dynamic permeability and printing ability of ink-jet paper were relative better.

A method for measuring the in-plane compressive strength and the compression behavior of coating layers

TAPPI Journal ◽  
2011 ◽  
Vol 10 (7) ◽  
pp. 29-34
Author(s):  
TEEMU PUHAKKA ◽  
ISKO KAJANTO ◽  
NINA PYKÄLÄINEN
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Calcium Carbonate ◽  
Coating Layer ◽  
Test Methods ◽  
Coating Films ◽  
Precipitated Calcium Carbonate ◽  
Coating Color ◽  
Mineral Coatings ◽  
Styrene Butadiene

Cracking at the fold is a quality defect sometimes observed in coated paper and board. Although tensile and compressive stresses occur during folding, test methods to measure the compressive strength of a coating have not been available. Our objective was to develop a method to measure the compressive strength of a coating layer and to investigate how different mineral coatings behave under compression. We used the short-span compressive strength test (SCT) to measure the in-plane compressive strength of a free coating layer. Unsupported free coating films were prepared for the measurements. Results indicate that the SCT method was suitable for measuring the in-plane compressive strength of a coating layer. Coating color formulations containing different kaolin and calcium carbonate minerals were used to study the effect of pigment particles’ shape on the compressive and tensile strengths of coatings. Latices having two different glass transition temperatures were used. Results showed that pigment particle shape influenced the strength of a coating layer. Platy clay gave better strength than spherical or needle-shaped carbonate pigments. Compressive and tensile strength decreased as a function of the amount of calcium carbonate in the coating color, particularly with precipitated calcium carbonate. We also assessed the influence of styrene-butadiene binder on the compressive strength of the coating layer, which increased with the binder level. The compressive strength of the coating layer was about three times the tensile strength.

Release Profile of a Model Protein Drug Depending on the Stability of Microspheres Based on Polyelectrolyte Complex

2007 ◽  
Vol 342-343 ◽  
pp. 505-508
Author(s):  
Sung Won Kim ◽  
Yun Sik Nam ◽  
Yeon Jin Min ◽  
Jong Ho Kim ◽  
Kwang Meyong Kim ◽  
...  
Keyword(s):  
Polyelectrolyte Complex ◽  
Coating Layer ◽  
Great Influence ◽  
Release Profile ◽  
Core Material ◽  
Glycol Chitosan ◽  
The Core ◽  
Key Factor ◽  
Model Protein ◽  
The Stability

Stability and disintegration of natural polyelectrolyte complex microspheres for protein drugs delivery have been extensively investigated because of their great influence on the drug release patterns. In this study, we tested stability of microspheres with alginate (Alg) core layered by either chitosan (Chi) or glycol chitosan (GChi) by examining release profiles of fluorophorelabeled bovine serum albumin (BSA) and lysozyme (Lys) from the microspheres. While GChi shell was disintegrated quickly, Chi-shell microspheres showed good stability in PBS. Disintegration of the coated layer induced the core material instable. The results indicated that while the charges of the shell material provided additional diffusion barrier against the protein release, the key factor to hold the proteins inside the microspheres was the integrity of the outer coating layer.

Effect of a thin surface coating layer on thermal stresses within an elastic half-plane

2006 ◽  
Vol 185 (3-4) ◽  
pp. 227-243 ◽  
Author(s):  
J. Yoon ◽  
C. Q. Ru ◽  
A. Mioduchowski
Keyword(s):  
Half Plane ◽  
Surface Coating ◽  
Thermal Stresses ◽  
Coating Layer

Characterization of Fe3O4@CS@NMDP magnetic nanoparticles with core–shell structure prepared by chemical cross-linking method

2017 ◽  
Vol 10 (05) ◽  
pp. 1750056 ◽  
Author(s):  
Huiping Shao ◽  
Jiangcong Qi ◽  
Tao Lin ◽  
Yuling Zhou ◽  
Fucheng Yu
Keyword(s):  
Magnetic Nanoparticles ◽  
Shell Structure ◽  
High Performance ◽  
Cross Linking ◽  
Composite Particles ◽  
Core Shell ◽  
The Core ◽  
Targeting Delivery ◽  
Core Shell Structure ◽  
Chemical Cross Linking

The core–shell structure composite magnetic nanoparticles (NPs), Fe3O4@chitosan@nimodipine (Fe3O4@CS@NMDP), were successfully synthesized by a chemical cross-linking method in this paper. NMDP is widely used for cardiovascular and cerebrovascular disease prevention and treatment, while CS is of biocompatibility. The composite particles were characterized by an X-ray diffractometer (XRD), a Fourier transform infrared spectroscopy (FT-IR), a transmission electron microscopy (TEM), a vibrating sample magnetometers (VSM) and a high performance liquid chromatography (HPLC). The results show that the size of the core–shell structure composite particles is ranging from 12[Formula: see text]nm to 20[Formula: see text]nm and the coating thickness of NMDP is about 2[Formula: see text]nm. The saturation magnetization of core–shell composite NPs is 46.7[Formula: see text]emu/g, which indicates a good potential application for treating cancer by magnetic target delivery. The release percentage of the NMDP can reach 57.6% in a short time of 20[Formula: see text]min in the PBS, and to 100% in a time of 60[Formula: see text]min, which indicates the availability of Fe3O4@CS@NMDP composite NPs for targeting delivery treatment.

scholarly journals The Effects of Magnetic Nanoparticles Incorporated in Polyelectrolyte Capsules

2017 ◽  
Vol 54 (4) ◽  
pp. 630-634
Author(s):  
Carmen Stavarache ◽  
Mircea Vinatoru ◽  
Timothy Mason ◽  
Larysa Paniwnyk
Keyword(s):  
Iron Oxide ◽  
Magnetic Nanoparticles ◽  
Calcium Carbonate ◽  
Ferric Oxide ◽  
Iron Content ◽  
Single Layer ◽  
Oxide Nanoparticles ◽  
Polyelectrolyte Multilayer ◽  
The Core ◽  
Calcium Carbonate Template

Polyelectrolyte multilayer capsules are synthesized comprising of 12 total layers each containing a single layer of iron oxide nanoparticles in shells 4, 6, 8 or 10. A protein-labelled dye is embedded in the calcium carbonate template core as a model for the encapsulation of a drug. The core is dissolved after 6 layers are formed. Two types of magnetic nanoparticles are incorporated into various capsule shells: ferric oxide (Fe2O3, 50 nm) and iron oxide (Fe3O4, 15 nm), a 1:1 (vol.) mixture of the two types of nanoparticles suspensions is also used. Nanoparticle inclusion reduces the capsule sizes in all cases with the order of effect Fe3O4 [ Fe2O3 [ Fe2O3/Fe3O4 mixture. When Fe3O4 or a Fe2O3/Fe3O4 mixture is incorporated in layer 6 the reduction in size of the final capsules is less than expected. The number of surviving capsules containing nanoparticles are lower than control regardless of which of the nanoparticles is used but here the effect of Fe3O4 or a mixture of the two types of nanoparticles incorporated in layer 6 was slightly out of step. The amount of iron incorporated is almost the same regardless of which shell the nanoparticles were incorporated but the iron content using 50 nm nanoparticles is generally slightly higher than that obtained with 15 nm nanoparticles.

scholarly journals Evaluation of Calcium Carbonate Inhibitors Using Sintered Metal Filter in a Pressurized Dynamic System

Materials ◽  
2019 ◽  
Vol 12 (11) ◽  
pp. 1849 ◽  
Author(s):  
Adriana Velloso Alves de Souza ◽  
Francisca Rosário ◽  
João Cajaiba
Keyword(s):  
Calcium Carbonate ◽  
Dynamic System ◽  
Heterogeneous Nucleation ◽  
Oil And Gas ◽  
Production Systems ◽  
Dynamic Test ◽  
Gas Production ◽  
Oil And Gas Production ◽  
Sintered Metal ◽  
Organophosphorus Inhibitors

Calcium carbonate scale is formed during oil and gas production. Tube-blocking tests (TBTs) are used to define the minimum inhibitory concentration (MIC) in order to prevent scale adhesion in the petroleum production system equipment. However, non-adhered crystals may favor heterogeneous nucleation to other deposits such as calcium naphthenates, causing a more severe scale problem, increasing production losses and treatment costs. The objective of the present work was to develop a new dynamic test methodology to determine the MIC for CaCO3 using a sintered metal filter. Organophosphorus inhibitors were selected for comparison with the conventional dynamic tube-blocking system. The results demonstrated that the use of the filter allowed an MIC of the inhibitors to be obtained considering the precipitation prevention. The inhibitor concentration in the conventional tube-blocking system does not prevent precipitation, acting only on adhesion and crystal growth on the capillary wall. Tests to evaluate the potential of calcium naphthenates formation in a naphthenate flow rig dynamic system demonstrated the influence of heterogeneous nucleation from non-adhered carbonate crystals, potentially aggravating deposition problems in oil and gas production systems.

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