Nanoparticle-coated elastomeric particulates and methods for production and use thereof

Patent metadata

Field	Value
Publication number	US-2021070953-A1
Application number	US-202016946626-A
Country	US
Kind code	A1
Filing date	Jun 30, 2020
Priority date	Sep 9, 2019
Publication date	Mar 11, 2021
Grant date	—

Abstract

Melt emulsification may be employed to form elastomeric particulates in a narrow size range when nanoparticles are included as an emulsion stabilizer. Such processes may comprise combining a polyurethane polymer and nanoparticles with a carrier fluid at a heating temperature at or above a melting point or a softening temperature of the polyurethane polymer, applying sufficient shear to disperse the polyurethane polymer as liquefied droplets in the presence of the nanoparticles in the carrier fluid at the heating temperature, cooling the carrier fluid at least until elastomeric particulates in a solidified state form, and separating the elastomeric particulates from the carrier fluid. In the elastomeric particulates, the polyurethane polymer defines a core and an outer surface of the elastomeric particulates and the nanoparticles are associated with the outer surface. The elastomeric particulates may have a D50 of about 1 μm to about 1,000 μm.

First claim

What is claimed is the following:

1 . A composition comprising:
a plurality of elastomeric particulates comprising a polyurethane polymer and a plurality of nanoparticles, the polyurethane polymer defining a core and an outer surface of the elastomeric particulates and the plurality of nanoparticles being associated with the outer surface;
wherein the elastomeric particulates have a D50 ranging from about 1 μm to about 1,000 μm

2 . The composition of claim 1 , wherein the elastomeric particulates have a standard deviation at the D50 ranging from about 80% to about 300% of the D50.

3 . The composition of claim 1 , wherein the plurality of nanoparticles comprises or consists essentially of a plurality of oxide nanoparticles.

4 . The composition of claim 3 , wherein the plurality of oxide nanoparticles comprises or consists essentially of silica nanoparticles.

5 . The composition of claim 4 , wherein the silica nanoparticles have a D50 ranging from about 1 nm to about 100 nm.

6 . The composition of claim 4 , wherein the silica nanoparticles are at least partially embedded in the outer surface.

7 . The composition of claim 4 , wherein the silica nanoparticles are coated as a substantially uniform layer on the outer surface.

8 . The composition of claim 1 , wherein at least a majority of the plurality of elastomeric particulates are substantially spherical in shape.

9 . A method comprising:
depositing the composition of claim 1 in a specified shape; and once deposited, heating at least a portion of the elastomeric particulates to promote consolidation thereof to form a consolidated body;
wherein the consolidated body is formed layer-by-layer and has a porosity of about 1% or less after being consolidated.

10 . The method of claim 9 , wherein depositing the composition and consolidating the elastomeric particulates takes place using a three-dimensional printing apparatus.

11 . The method of claim 9 , wherein the plurality of nanoparticles remain associated with the consolidated body.

12 . The method of claim 9 , wherein the plurality of nanoparticles comprises or consists essentially of a plurality of oxide nanoparticles.

13 . The method of claim 12 , wherein the plurality of oxide nanoparticles comprises or consists essentially of silica nanoparticles.

14 . A method comprising:
combining a polyurethane polymer and nanoparticles with a carrier fluid at a heating temperature at or above a melting point or a softening temperature of the polyurethane polymer;
wherein the polyurethane polymer and the carrier fluid are substantially immiscible at the heating temperature;
applying sufficient shear to disperse the polyurethane polymer as liquefied droplets in the presence of the nanoparticles in the carrier fluid at the heating temperature; after liquefied droplets have formed, cooling the carrier fluid to at least a temperature at which elastomeric particulates in a solidified state form, the elastomeric particulates comprising the polyurethane polymer and a plurality of the nanoparticles, the polyurethane polymer defining a core and an outer surface of the elastomeric particulates and the plurality of the nanoparticles being associated with the outer surface;
wherein the elastomeric particulates have a D50 ranging from about 1 μm to about 1,000 μm; and
separating the elastomeric particulates from the carrier fluid.

15 . The method of claim 14 , wherein the plurality of nanoparticles comprises or consists essentially of a plurality of oxide nanoparticles.

16 . The method of claim 15 , wherein the plurality of the oxide nanoparticles comprises or consists essentially of silica nanoparticles.

17 . The method of claim 14 , wherein the carrier fluid has a viscosity at 25° C. ranging from about 1,000 cSt to about 150,000 cSt.

18 . The method of claim 17 , wherein the carrier fluid comprises a silicone oil.

19 . The method of claim 14 , wherein a solids loading in the carrier fluid ranges from about 20% to about 50% by weight.

20 . The method of claim 14 , wherein a loading of the nanoparticles in the carrier fluid ranges from about 0.1 wt. % to about 5 wt. % with respect to a loading of the polyurethane polymer in the carrier fluid.

Assignees

• Xerox Corp

Inventors

• Resetco Cristina
• Sriskandha Shivanthi Easwari
• Zwartz Edward G
• Hawkins Michael S
• Farrugia Valerie M

Classifications

• Y02P10/25

  Process efficiency · CPC title

• C08L83/04 Primary

  Polysiloxanes · CPC title

• B29C64/295

  Heating elements · CPC title

• B29C64/106

  using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material · CPC title

• C08K2201/006

  Additives being defined by their surface area · CPC title