Method of preparing a product comprising surface modified silver nanowires, and use of the product

Patent metadata

Field	Value
Publication number	US-11149153-B2
Application number	US-201716091856-A
Country	US
Kind code	B2
Filing date	Apr 4, 2017
Priority date	Apr 6, 2016
Publication date	Oct 19, 2021
Grant date	Oct 19, 2021

Abstract

Described is a method of preparing a product comprising an amount of surface modified silver nanowires, the method comprising the following steps: preparing or providing a first surface agent compound having one or more functional groups selected from the group consisting of thiol and amine, for attaching the first surface agent compound to the surface of a silver nanowire, preparing or providing an amount of silver nanowires, attaching said first surface agent compound prepared or provided in step (a) to the surface of said silver nanowires prepared or provided in step (b), so that surface modified silver nanowires result, and optionally (d) adding one or more further constituents and/or conducting one or more further steps so that said product results. Also described are a corresponding product, corresponding uses and a method of coating the surface of an article.

First claim

The invention claimed is:

1. A method of preparing a product comprising an amount of surface modified silver nanowires dispersed in a product dispersion medium, the method comprising
(a) preparing or providing a first surface agent compound having one or more functional groups selected from the group consisting of thiol, for attaching the first surface agent compound to the surface of a silver nanowire,
wherein said first surface agent compound comprises a poly(ethylene glycol) methyl ether thiol (PEGT),
(b) preparing or providing an amount of silver nanowires which is dispersed in an intermediate dispersion medium, attaching a second surface agent compound different from the first surface agent compound to the surface of said silver nanowires,
and/or
the amount of silver nanowires is prepared using a polyol process and a second surface agent compound different from the first surface agent compound is attached to the surface of said silver nanowires,
(c) attaching said first surface agent compound to the surface of said silver nanowires to obtain the surface modified silver nanowires,
after (b) and before, in or after (c), said intermediate dispersion medium is partially or completely exchanged against an additive dispersion medium which is different from the intermediate dispersion medium, and
said additive dispersion medium comprises one or more compounds selected from the group consisting of a substituted or an unsubstituted, a branched or a linear, and an aliphatic or an aromatic organic compound having a total number of carbon atoms of at least 4
and optionally
(d) adding one or more further constituents and/or conducting one or more further steps
to obtain said product.

2. The method according to claim 1 , wherein the product dispersion medium consists of an additive dispersion medium or a mixture of an additive dispersion medium and an intermediate dispersion medium.

3. The method according to claim 1 , wherein in (c) said second surface agent compound is partially or completely removed from the surface of said silver nanowires prepared or provided in (b).

4. The method according to claim 1 , wherein
in (b)
and
in one or more further steps after (c) said intermediate dispersion medium is partially or completely exchanged against an additive dispersion medium which is different from the intermediate dispersion medium.

5. The method according to claim 1 , wherein
in (b) the amount of silver nanowires is dispersed in the intermediate dispersion medium in a concentration of from 0.001 wt.-% to 2 wt.-%, based on a total amount of the intermediate dispersion, and the intermediate dispersion has a homogeneity index of at least 80%,
and/or
said product is a product dispersion which comprises an amount of the surface modified silver nanowires dispersed in the product dispersion medium in a concentration of from 0.001 wt.-% to 2 wt.-%, based on a total amount of the product dispersion and the product dispersion has a homogeneity index of at least 80%.

6. The method according to claim 1 , wherein said intermediate dispersion medium and/or said additive dispersion medium has a boiling point >30° C. at 1013 hPa.

7. The method according to claim 1 , wherein
a ratio of a total weight of surface agent compounds attached to the surface of said surface modified silver nanowires to a total weight of said surface modified silver nanowires is in the range of from 0.01 to 0.3 and is determined by thermogravimetry.

8. The method according to claim 1 , wherein said first surface agent compound has a weight average molecular weight of from 500 to 500 000 g/mol.

9. The method according to claim 1 , wherein the product dispersion medium comprises one or more compounds selected from the group consisting of water, ethanol, 2-propanol, dipropylene glycol methyl ether acetate, butyl acetate and THF.

10. The method according to claim 1 , wherein the intermediate dispersion medium comprises one or more compounds selected from the group consisting of water, acetone, methanol, ethanol, propan-1-ol, propan-2-ol, 1-hydroxybutane, 2-hydroxybutane, 1-hydroxy-2-methylpropane, 2-hydroxy-2-methylpropane, formic acid, acetic acid, propionic acid and aniline.

11. The method according to claim 1 , wherein the additive dispersion medium comprises one or more compounds selected from the group consisting of 1-hydroxypentane, 2-hydroxypentane, 1-hydroxy-2-methylpentane, 2-hydroxy-2-methylpentane, diethyl ether, tetrahydrofuran, diisopropyl ether, dipropylene glycol methyl ether acetate, ethyl acetate, butyl acetate, ethyl lactate, butyl hydroxyacetate, 2-butanone, 2-pentanone, 2-hexanone isophorone and an aromatic hydrocarbon.

Assignees

• Basf Se

Inventors

• Chu Fangfang
• Dietsch Herve
• Sturm Thomas
• Seyfried Danny

Classifications

• B22F1/0545 Primary

  Dispersions or suspensions of nanosized particles · CPC title

• B22F1/0547

  Nanofibres or nanotubes · CPC title

• C09D7/70

  characterised by shape, e.g. fibres, flakes or microspheres · CPC title

• C09D11/037

  characterised by the pigment · CPC title

• B22F2301/255

  Silver or gold · CPC title