Polymer matrix composites comprising intumescent particles and methods of making the same

Patent metadata

Field	Value
Publication number	US-2019144625-A1
Application number	US-201816191554-A
Country	US
Kind code	A1
Filing date	Nov 15, 2018
Priority date	Nov 16, 2017
Publication date	May 16, 2019
Grant date	—

Abstract

Polymer matrix composite comprising a porous polymeric network; and a plurality of intumescent particles distributed within the polymeric network structure; wherein the intumescent particles are present in a range from 15 to 99 weight percent, based on the total weight of the intumescent particles and the polymer (excluding the solvent); and wherein the polymer matrix composite volumetrically expands at least 2 times its initial volume when exposed to at least one temperature greater than 135° C.; and methods for making the same. The polymer matrix composites are useful, for example, as fillers, thermally initiated fuses, and fire stop devices.

First claim

What is claimed is:

1 . A polymer matrix composite comprising:
a porous polymeric network structure; and a plurality of intumescent particles distributed within the polymeric network structure, wherein the intumescent particles are present in a range from 15 to 99 weight percent, and wherein the polymer matrix composite volumetrically expands at least 2 times its initial volume when exposed to at least one temperature greater than 135° C.

2 . The polymer matrix composite of claim 1 , wherein the polymer matrix composite has a density of at least 0.3 g/cm 3 .

3 . The polymer matrix composite of claim 1 , wherein the polymer matrix composite has a porosity at least 5 percent.

4 . The polymer matrix composite of claim 1 , wherein the intumescent particles comprise at least one of sodium silicate, intercalated graphite, aluminum hydroxide, magnesium hydroxide, ammonium polyphosphate, clay, or vermiculite.

5 . The polymer matrix composite of claim 1 , wherein the intumescent particles have an average particle size in a range from 500 nanometers to 7000 micrometers.

6 . The polymer matrix composite of claim 1 , wherein the porous polymeric network structure comprises at least one of polyurethane, polyester, polyamide, polyether, polycarbonate, polyimide, polysulfone, polyethersulfone, polyphenylene oxide, polyacrylate, polymethacrylate, polyacrylonitrile, polyolefin, styrene or styrene-based random and block copolymer, chlorinated polymer, fluorinated polymer, or copolymers of ethylene and chlorotrifluoroethylene.

7 . The polymer matrix composite of claim 1 , wherein the porous polymeric network structure comprises a phase-separated plurality of interconnected morphologies.

8 . The polymer matrix composite of claim 1 , wherein the porous polymeric network structure comprises a polymer having a number average molecular weight in a range from of 5×10 4 to 1×10 7 g/mol, and wherein the polymer matrix composite is in the form of a layer having a thickness in a range from 50 to 7000 micrometers.

9 . A method of making the polymer matrix composite of claim 1 , the method comprising:
combining a thermoplastic polymer, a solvent, and a plurality of intumescent particles to provide a slurry; forming the slurry in to an article; heating the article in an environment to retain at least 90 percent by weight of the solvent in the article, based on the weight of the solvent in the article, and solubilize at least 50 by weight percent of the thermoplastic polymer, based on the total weight of the thermoplastic polymer; and inducing phase separation of the thermoplastic polymer from the solvent to provide the polymer matrix composite.

10 . The method of claim 9 , further comprising removing at least a portion of the solvent from the formed article after inducing phase separation of the thermoplastic polymer from the solvent.

11 . The method of claim 10 , wherein no solvent is removed from the formed article.

12 . The method of claim 9 , wherein inducing phase separation includes thermally induced phase separation.

13 . The method of claim 9 , wherein the polymer in the slurry has a melting point, wherein the solvent has a boiling point, and wherein combining is conducted below the melting point of the polymer in the slurry, and below the boiling point of the solvent.

14 . The method of claim 9 , wherein the polymer in the slurry has a melting point, and wherein inducing phase separation is conducted at less than the melting point of the polymer in the slurry.

15 . The method of claim 9 , further comprising compressing the polymer matrix composite.

16 . The method of claim 9 , further comprising applying vibratory energy to the polymer matrix composite simultaneously with the applying a compressive force.

17 . A method of making the polymer matrix composite of claim 1 , the method comprising:
combining a thermoplastic polymer, a solvent for the thermoplastic, and a plurality of intumescent particles to form a suspension of intumescent particles in a miscible thermoplastic polymer-solvent solution; inducing phase separation of the thermoplastic polymer from the solvent; and removing at least a portion of the solvent to provide the polymer matrix composite.

18 . The method of claim 17 , wherein inducing phase separation includes at least one of thermally induced phase separation or solvent induced phase separation.

19 . The method of claim 18 , wherein the polymer in the miscible thermoplastic polymer-solvent solution has a melting point, wherein the solvent has a boiling point, and wherein combining is conducted above the melting point of the miscible thermoplastic polymer-solvent solution, and below the boiling point of the solvent.

20 . The method of claim 17 , wherein the polymer in the miscible thermoplastic polymer-solvent solution has a melting point, and wherein inducing phase separation is conducted at less than the melting point of the polymer in the miscible thermoplastic polymer-solvent solution.

21 . The method of claim 17 , further comprising compressing the polymer matrix composite.

22 . The method of claim 17 , further comprising applying vibratory energy to the polymer matrix composite simultaneously with the applying a compressive force.

23 . An apparatus comprising the polymer matrix composite of claim 1 .

Assignees

• 3M Innovative Properties Co

Inventors

• Acharya Bharat R
• Bartling Brandon A
• Dehn Derek J
• Hines Paul T
• Waller Jr Clinton P
• Nayar Satinder K

Classifications

• C08J2205/05

  Open cells, i.e. more than 50% of the pores are open · CPC title

• C08J3/212

  and solid additives · CPC title

• C08L101/14

  the macromolecular compounds being water soluble or water swellable, e.g. aqueous gels · CPC title

• C08K2003/2227

  of aluminium · CPC title

• C08K2201/005

  Additives being defined by their particle size in general · CPC title