Friedel-Crafts alkylation modification and hydrophilic soft finishing of meta aramid

Based on the Friedel-Crafts alkylation reaction, epichlorohydrin is applied to decorate the meta aramid to enhance the comfort of the fabrics. It is obviously more perfect that the samples are treated with the hydrophilic soft finishing agent. In this paper, the effects of modification and finishing time on the structure and properties of meta aramid are studied. The results indicate that the surface roughness, polarity, active point, and wetting property of the modified fabrics are increased, and the loading rate and fastness of the finishing agent on the meta aramid are enhanced. After finishing, the wetting time and the time of water transfer from the surface to the bottom become shorter in the fabrics, and the water absorption rate becomes faster, the core absorption height rises by 60%, the bending stiffness lowers by 39%, the moisture permeability increases by 5.9%, the permeability decreases by 3.6%, and the friction electric voltage reduces by 78%, The longitudinal and weft secondary combustion time increase by 0.3 s and 0.2 s, the smoldering time increase by 0.3 s, and the improving rate of damage length are 5.4% and 7.6%, respectively.

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Preparation, Structure and Properties of FeCrAl Honeycombs

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.833.305 ◽

2013 ◽

Vol 833 ◽

pp. 305-309

Author(s):

Jiao Yu ◽

Yu Jie Du ◽

Yun Zhou

Keyword(s):

Cross Section ◽

Alloy Powder ◽

Xrd Analysis ◽

Cell Number ◽

Structure Parameters ◽

Time Increase ◽

Structure And Properties ◽

Active Components ◽

Fecral Alloy ◽

Sintering Time

FeCrAl alloy powder is used to mix with an additive to prepare a powder mixed paste. FeCrAl alloy honeycombs are fabricated by extruding the powder mixed paste, then dried and sintered. While sintering at 1200°C, with sintering time increase, the volume of sintered honeycombs increase and density decrease. The structure parameters and properties of sintered honeycombs were obtained by measuring and calculating. Results show that wall thickness 0.18~0.23mm, cell number (1/in2) 316~339, clear cross section (%) 69~74, specific surface Sv (sq m/cu dm)2.35~2.52; specific heat capacity Cp(J/g.K) 0.60~0.70, heat conductivity κ (W/m.K) 6.52~6.78. SEM/XRD analysis shows that a large number of oxides formed on the surface of sintered honeycombs during sintering, such as Fe2Cr204, Fe2Si04, Al2O3.These oxides connect together to form film on surface of sintered honeycombs. By impregnating and baking test, the surface of sintered honeycomb can firmly adhere γ-Al2O3catalytic washcoat. The oxide film formed on the surface sintered honeycombs is benefit for adhering and supporting the catalytic active components.

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Effect of Li2O on Structure and Properties of Glass-Ceramic Bonds

10.21203/rs.3.rs-55577/v1 ◽

2020 ◽

Author(s):

Zichen Guo ◽

Feng He ◽

Zuhao Li ◽

Dongyang Yan ◽

Bing Zhang ◽

...

Keyword(s):

Glass Ceramic ◽

Bending Strength ◽

Sintering Temperature ◽

Linear Shrinkage ◽

Interfacial Bonding ◽

Structure And Properties ◽

Interfacial Bonding Strength ◽

Wetting Property ◽

Sintering Properties ◽

Abrasive Tools

Abstract SiO2-B2O3-Al2O3-CaO vitrified bonds are widely used in the diamond abrasive tools preparation. The effect of Li2O on structure and properties of the glass-ceramic bonds was investigated. The structure of the glass-ceramic bonds was analyzed by XRD and FTIR. The bending strength, the sintering properties of different glass-ceramic bonds and the thermal expansion coefficient were tested at meantime. The sintering and interfacial bonding state between L-4 glass-ceramic bonds and diamond grains were observed by SEM. The results showed that with the increasing of Li2O, the sintering temperature of the glass-ceramic bonds was impactful reducing. When the content of Li2O was 4 wt%, the sintering temperature corresponding to the optimal bending strength was 630 °C, which had a certain reduction compared with other studies. The main crystal phase precipitated in the glass-ceramic bonds was LixAlxSi3−xO6. With the increase of Li2O, the number of crystals in the glass-ceramic bonds gradually increased. The highest bending strength could attain about 136 MPa. Meanwhile, the bending strength performed regular change as the rising of temperature accompanied by the linear shrinkage rate. The L-4 glass-ceramic bonds and diamond grains were found to have very good wetting property and the interfacial bonding strength was insured enhance. The average bending strength of the composite sinter of the glass-ceramic bonds and diamond was up to 87.8 MPa.

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Structure of second phases in TiAl alloys containing Cr and B

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100087197 ◽

1991 ◽

Vol 49 ◽

pp. 576-577

Author(s):

Ernest L. Hall ◽

Shyh-Chin Huang

Keyword(s):

Grain Size ◽

Second Phase ◽

Structure And Properties ◽

Tial Alloys ◽

Second Phases ◽

Interstitial Elements

Addition of interstitial elements to γ-TiAl alloys is currently being explored as a method for improving the properties of these alloys. Previous work in which a number of interstitial elements were studied showed that boron was particularly effective in refining the grain size in castings, and led to enhanced strength while maintaining reasonable ductility. Other investigators have shown that B in γ-TiAl alloys tends to promote the formation of TiB2 as a second phase. In this study, the microstructure of Bcontaining TiAl alloys was examined in detail in order to describe the mechanism by which B alters the structure and properties of these alloys.

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Relationships between hierarchical structure and properties in macromolecular systems

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126950 ◽

1987 ◽

Vol 45 ◽

pp. 440-443

Author(s):

E. Baer

Keyword(s):

Uniaxial Tension ◽

Hierarchical Structure ◽

Inorganic Material ◽

Hierarchical Structures ◽

Bone Collagen ◽

Structure And Properties ◽

Connective Tissues ◽

Scale Level ◽

Fibrous Protein ◽

Macromolecular Systems

The most advanced macromolecular materials are found in plants and animals, and certainly the connective tissues in mammals are amongst the most advanced macromolecular composites known to mankind. The efficient use of collagen, a fibrous protein, in the design of both soft and hard connective tissues is worthy of comment. Very crudely, in bone collagen serves as a highly efficient binder for the inorganic hydroxyappatite which stiffens the structure. The interactions between the organic fiber of collagen and the inorganic material seem to occur at the nano (scale) level of organization. Epitatic crystallization of the inorganic phase on the fibers has been reported to give a highly anisotropic, stress responsive, structure. Soft connective tissues also have sophisticated oriented hierarchical structures. The collagen fibers are “glued” together by a highly hydrated gel-like proteoglycan matrix. One of the simplest structures of this type is tendon which functions primarily in uniaxial tension as a reinforced elastomeric cable between muscle and bone.

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The Structure and Properties of MoSi2 Thin Film in Mos Process

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600001379 ◽

1980 ◽

Vol 38 ◽

pp. 326-327

Author(s):

C.K. Wu ◽

P. Chang ◽

N. Godinho

Keyword(s):

Thin Film ◽

Integrated Circuits ◽

High Performance ◽

Large Scale ◽

Process Development ◽

Structure And Properties ◽

Metal Silicides ◽

High Oxidation ◽

Important Approach ◽

High Oxidation Resistance

Recently, the use of refractory metal silicides as low resistivity, high temperature and high oxidation resistance gate materials in large scale integrated circuits (LSI) has become an important approach in advanced MOS process development (1). This research is a systematic study on the structure and properties of molybdenum silicide thin film and its applicability to high performance LSI fabrication.

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