VroniPlag Wiki

This Wiki is best viewed in Firefox with Adblock plus extension.

MEHR ERFAHREN

VroniPlag Wiki
Registrieren

Angaben zur Quelle [Bearbeiten]

Autor     Evonik
Titel    Technical Bulletin Fine Particles AEROSIL® Fumed Silica in Unsaturated Polyester Resins and Vinyl Ester Resins
Herausgeber    Evonik Degussa GmbH
Jahr    2009
URL    http://web.archive.org/web/20140913000210/http://www.aerosil.com/product/aerosil/Documents/TB-54-AEROSIL-in-UP-Resins-and-Vinyl-Ester-Resins-EN.pdf

Literaturverz.   

no
Fußnoten    no
Fragmente    3


Fragmente der Quelle:
[1.] Mrs/Fragment 037 13 - Diskussion
Zuletzt bearbeitet: 2015-05-16 13:17:58 Hindemith
Evonik 2009, Fragment, Gesichtet, Mrs, SMWFragment, Schutzlevel sysop, Verschleierung

Typus
Verschleierung
Bearbeiter
SleepyHollow02
Gesichtet
Yes
Untersuchte Arbeit:
Seite: 37, Zeilen: 13-20
Quelle: Evonik 2009
Seite(n): 4, Zeilen: l.col.: 19 ff.
Siloxane (ºSi-O-Siº) and silanol (ºSi-OH) groups are situated on the surface of fumed silica particles. This latter type (i.e. silanol) of functional groups in particular is responsible for the hydrophilic behavior of non-after treated fumed silica types. Figure 3.4 shows the surface groups of hydrophilic AEROSIL fumed silica. AEROSIL fumed silica can be surface-modified by reacting the silanol groups with suitable compounds such as silanes. For example Aerosil R972, is produced by reacting hydrophilic silica with dimethylchlorosilane as shown in Figure 3.5 .this product exhibits chemically bound dimethyl silyl groups on its surface and can no longer be wetted with water – in other words, it is hydrophobic. Siloxane and silanol groups are situated on the surface of AEROSIL® particles. This latter type of functional group in particular is responsible for the hydrophilic behavior of non-aftertreated AEROSIL® types. Figure 1 shows the surface groups of hydrophilic AEROSIL® fumed silica. For basic details and applications of AEROSIL® fumed silica, see issue number 11 of the pigments publication series [1].

AEROSIL® fumed silica can be surface-modified by reacting the silanol groups with suitable compounds such as silanes. AEROSIL® R 972 is obtained by reaction with dimethyl-dichlorosilane, for example; this product exhibits chemically bound dimethyl silyl groups on its surface and can no longer be wetted with water – in other words, it is hydrophobic.


(1) Technical Bulletin Fine Particles, No. 11, Basic Characteristics of AEROSIL® fumed silica, 6th edition 2003, Degussa AG, D-40402 Düsseldorf, Germany

Anmerkungen

The source is not mentioned.

Sichter
(SleepyHollow02), Hindemith


[2.] Mrs/Fragment 038 01 - Diskussion
Zuletzt bearbeitet: 2015-05-16 13:09:33 Hindemith
BauernOpfer, Evonik 2009, Fragment, Gesichtet, Mrs, SMWFragment, Schutzlevel sysop

Typus
BauernOpfer
Bearbeiter
SleepyHollow02
Gesichtet
Yes
Untersuchte Arbeit:
Seite: 38, Zeilen: 1 ff. (entire page)
Quelle: Evonik 2009
Seite(n): 4, Zeilen: r.col.: 1 ff.
Mrs 038a diss

Figure 3.4 potential SiO2 surface groups of hydrophilic silicas [140]

AEROSIL R 972 became the first hydrophobic silica to be manufactured on an industrial scale in 1962. Further hydrophobic AEROSIL grades are now available, produced by similar industrial-scale methods using corresponding silanes. Figure 3.5 provides a sampling of the many hydrophobic grades available and highlights the difference between them and hydrophilic AEROSIL grades according to the schematically represented surface groups. All hydrophobic AEROSIL types carry the suffix “R“ to indicate their water-repellent character.

Mrs 038b diss

Figure 3.5 Hydrophobic Aerosil grade and their surface groups [140]


[140] Technical Bulletin Fine Particles, No. 11, Basic Characteristics of AEROSILR fumed silica, 6th edition 2003, Degussa AG, D-40402 Dusseldorf,Germany

Figure 1 Potential SiO 2 surface groups of hydrophilic silicas

Mrs 038a source

AEROSIL® R 972 became the first hydrophobic silica to be manufactured on an industrial scale in 1962. Further hydrophobic AEROSIL® grades are now available, produced by similar industrial-scale methods using corresponding silanes. Figure 2 provides a sampling of the many hydrophobic grades available and highlights the difference between them and hydrophilic AEROSIL® grades according to the schematically represented surface groups. All hydrophobic AEROSIL® types carry the suffix „R“ to indicate their water-repellent character.

Figure 2 Hydrophobic AEROSIL® grades and their surface groups

Mrs 038b source

Anmerkungen

The reference [140] might be a previous edition of the source documented here.

The figures are therefore referenced appropriately, the text between the figures, however, is not referenced at all.

Sichter
(SleepyHollow02), Hindemith


[3.] Mrs/Fragment 039 01 - Diskussion
Zuletzt bearbeitet: 2015-05-16 13:15:16 Hindemith
Evonik 2009, Fragment, Gesichtet, Mrs, SMWFragment, Schutzlevel sysop, Verschleierung

Typus
Verschleierung
Bearbeiter
SleepyHollow02
Gesichtet
Yes
Untersuchte Arbeit:
Seite: 39, Zeilen: 1-9
Quelle: Evonik 2009
Seite(n): 5, Zeilen: l.col.: 1 ff.
Hydrophilic and hydrophobic fumed silica grades have proven effective for numerous areas of application. In view of their use in the plastics industry, the principal properties of fumed silicas are listed below:

• Reinforcing fillers

• Thickening and thixotropic agent for resins

• Anti-sedimentation agent for cast resins and adhesives

• Free flow aid for powder coatings [sic!] In contrast to silicas of mineral origin, meaning quartz powder which is used mainly as a “filler“ in the true sense of the word, the desired effects can be obtained by adding only relatively small amounts of synthetic silicas.

Hydrophilic and hydrophobic AEROSIL® grades have proven effective for numerous areas of application. In view of their use in the plastics industry, the principal properties of fumed silicas are listed below:

• Reinforcing fillers

• Thickening and thixotropic agent for resins

• Anti-sedimentation agent for cast resins and adhesives

• Free flow aid for powder coatings

In contrast to silicas of mineral origin, meaning quartz powder which is used mainly as a „filler“ in the true sense of the word, the desired effects can be obtained by adding only relatively small amounts of synthetic silicas.

Anmerkungen

The source is not mentioned. At the place marked with [sic!] an empty line is missing. Note that when copying and pasting from the source text, the empty line in the source text is omitted.

Sichter
(SleepyHollow02), Hindemith