CN-122013171-A - Iron particle passivation

Abstract

The present invention relates to iron particle passivation. The present disclosure provides a coated iron particle or a reaction product thereof that includes an iron particle and a thiol coating disposed on the iron particle. The present disclosure also provides a composition comprising coated iron particles and a polymer or adhesion promoter. The present disclosure also provides an assembly having a surface and the composition of the present disclosure disposed on the surface. A method of passivating iron particles may include introducing a passivating agent having one or more sulfur moieties into a solvent to form a passivating solution, and contacting the iron particles with the passivating solution to form coated iron particles. A method of passivating iron particles may include introducing iron particles into a solvent to form an iron particle solution, and contacting a passivating agent having one or more sulfur moieties with the iron particle solution to form coated iron particles.

Inventors

• P.J. Karen

Assignees

• 波音公司

Dates

Publication Date

20260512

Application Date

20181011

Priority Date

20171103

Claims (10)

1. 1. A coated iron particle or reaction product thereof, comprising: iron particles having a diameter of about 0.5 microns to about 1,000 microns, and A thiol coating disposed on the iron particles.
2. 2. The coated iron particle of claim 1, wherein the iron particle has a diameter of about 1 micron to about 1,000 microns.
3. 3. The coated iron particle of claim 2, wherein the iron particle has an iron content of about 99wt% or greater.
4. 4. The coated iron particle of claim 1, wherein the thiol coating has a thickness of about 10 angstroms to about 1,000 angstroms.
5. 5. The coated iron particle of claim 4, wherein the coated iron particle has a thiol coating content of about 1vol% to about 10vol%, based on the total volume of the thiol coated iron particle, as determined by the difference in weight and density of the particle before and after coating the particle.
6. 6. The coated iron particle of claim 4, wherein the coated iron particle has a thiol coating content of about 1wt% to about 10wt%, based on the total weight of the thiol coated iron particle, as determined by the difference in weight of the particle before and after coating the particle.
7. 7. The coated iron particle of claim 6, wherein the coated iron particle has a thiol coating content of about 2wt% to about 5wt%, based on the total weight of the thiol coated iron particle, as determined by the difference in weight of the particle before and after coating the particle.
8. 8. The coated iron particle of claim 1, wherein the ratio of Xs to particle diameter of the coated iron particle is from about 0.5:1 to about 1.5:1.
9. 9. The coated iron particle of claim 1, wherein the thiol coating comprises a thiol compound selected from the group consisting of heterocyclic thiols, disulfides, thiolate compounds, and alkyl polythiols, or a reaction product thereof.
10. 10. The coated iron particle of claim 9, wherein the thiol coating comprises an alkyl polythiol selected from the group consisting of ethanedithiol, propanedithiol, butanedithiol, pentanedithiol, hexanedithiol, pentanedithiol, octanedithiol, nonanedithiol, and decanedithiol, or a reaction product thereof.

Description

Iron particle passivation The application is a divisional application, the application date of the original application is 2018, 10, 11, 2018111815451, and the application is named as iron particle passivation. Technical Field Aspects of the present disclosure provide thiol-coated iron particles, compositions comprising thiol-coated iron particles, components on which the compositions are disposed, and methods of passivating iron particles. Background In recent years, magnetic particles have received significant attention, particularly iron particles, which are commonly used due to their excellent magnetic properties. They can be applied in various technical fields, biomedical applications, absorption and catalyst processes or in the production of magnetorheological fluids and composites. The iron particles may be nano, micro or macro sized, depending on the size desired. For example, carbonyl iron particles are a major component for designing magnetic type electromagnetic wave absorbers. Carbonyl iron is substantially pure iron (99.9% iron content or greater) formed from iron-containing carbonyl moieties such as Fe (CO) 5. For example, carbonyl Iron Powder (CIP) has specific magnetic properties, is useful in many applications and is an ideal additive for coatings due to these magnetic properties. However, carbonyl iron is susceptible to oxidation and corrosion at high temperatures, resulting in reduced magnetic properties. Furthermore, uniform dispersion of CIP is a challenge, and failure to properly disperse can affect CIP performance. For example, processes such as coating particles with polymers may cause agglomeration of the particles and may hinder dispersion of the particles. For example, iron silicate (silicon iron) has been used instead of carbonyl iron because it is less susceptible to corrosion and easier to process. Known passivation techniques for carbonyl iron or iron silicate include carbon dioxide passivation, cobalt electroless plating, polyaniline passivation, microwave plasma processes, and silica coatings. These methods involve numerous/complex processing steps, resulting in a substantial increase in the mass and volume of the particles, resulting in aggregation of the resulting particles, and may reduce the magnetic properties of the particles. There is a need for passivated iron particles with retained or improved magnetic properties and improved methods of passivating iron particles. Disclosure of Invention The present disclosure provides coated iron particles or reaction products thereof comprising iron particles and a thiol coating disposed on the iron particles. Aspects of the present disclosure also provide compositions comprising coated iron particles and a polymer or adhesion promoter. Aspects of the present disclosure also provide components, such as vehicle components, that include a surface and the composition of the present disclosure disposed on the surface. Aspects of the present disclosure also provide methods of passivating iron particles by introducing a passivating agent having one or more sulfur moieties into a solvent to form a passivating solution, and contacting the iron particles with the passivating solution to form coated iron particles. Aspects of the present disclosure further provide methods of passivating iron particles by introducing the iron particles into a solvent to form an iron particle solution, and contacting a passivating agent having one or more sulfur moieties with the iron particle solution to form coated iron particles. Drawings So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to some of the aspects thereof which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical aspects of this disclosure and are therefore not to be considered limiting of its scope, for the disclosure may admit to other equally effective aspects. Fig. 1 is an aircraft including a vehicle component in accordance with at least one aspect of the present disclosure. Fig. 2 is a flow chart of a method for forming thiol-coated iron particles according to at least one aspect of the present disclosure. Fig. 3A is a scanning electron microscope image of a carbonyl iron particle without thiol passivation in accordance with at least one aspect of the present disclosure. Fig. 3B is a scanning electron microscope image of a carbonyl iron particle without thiol passivation in accordance with at least one aspect of the present disclosure. Fig. 3C is a scanning electron microscope image of a carbonyl iron particle without thiol passivation in accordance with at least one aspect of the present disclosure. Fig. 4A is a scanning electron microscope image of carbonyl iron particles passivated with 2, 5-dimercapto-1, 3, 4-thiadiazole in accordance with at least one aspect