Method of making cured parts

Patent metadata

Field	Value
Publication number	US-11208540-B2
Application number	US-201816499866-A
Country	US
Kind code	B2
Filing date	Mar 23, 2018
Priority date	Mar 31, 2017
Publication date	Dec 28, 2021
Grant date	Dec 28, 2021

Abstract

The invention pertains to a method of making cured parts from a composition comprising certain fluoroelastomers and certain bromine-containing compounds under conditions suitable for delivering cured parts possessing outstanding mechanical and sealing properties and incorporating suitable amounts of bromine-containing compounds, so that these cured parts, when submitted to wear/damage would release Br-containing compounds, which can easily detected using appropriate analytical techniques, so as to monitor and anticipate critical failures thereof.

First claim

The invention claimed is:

1. A method of making a cured shaped article [article (P)], said method comprising:
molding a composition (C) under heating for a time of at least 30 minutes at a temperature of at most 200° C., wherein composition (C) is a fluoroelastomer composition comprising:
at least one fluoroelastomer (A) comprising from 0.1 to 10.0% moles, with respect to total moles of recurring units of fluoroelastomer (A), of recurring units derived from at least one cure-site containing monomer having at least a nitrile group [monomer (CS-N)];

at least one curing agent [agent (A)]; and
at least one bromine-containing marker [marker (B)], wherein marker (B) complies with formula (B-1) below:

wherein Ar B1 is an aromatic group, optionally comprising fluorine atoms; and n is zero or is an integer of 1 to 4.

2. The method according to claim 1 , wherein the agent (A) is selected from compounds possessing catalytic activity towards activation of nitrile groups of monomer (CS-N), and wherein the agent (A) is referred to as an agent (A cat ), and is selected from the group consisting of:
an organic ammonia-generating compound, able to generate ammonia upon heating; and
an organotin compound.

3. The method according to claim 2 , wherein the agent (A cat ) is selected from the group consisting of:
(A cat -1): (thio)urea compounds of formula (U) and salts thereof:

wherein E is O or S, and each of R u , equal to or different from each other, is independently selected from the group consisting of hydrogen and C 1 -C 6 hydrocarbon groups;
(A cat -2): cyclic addition products of ammonia or primary amine and aldehyde;
(A cat -3): (thio)carbamates of formula (C):

wherein E is oxygen or sulphur; R b is a C 1 -C 36 hydrocarbon group, and R c is H or a C 1 -C 6 alkyl group; and
(A cat -4): ammonium salts of organic and inorganic acids.

4. The method according to claim 3 , wherein agent (A cat ) is selected from the group consisting of:
(A cat -1-A) (thio)ureas of formula (U-2):

wherein E′ is O or S;
(A cat -2-A) cyclic aldehyde adducts trimers of formula (T):

wherein each of R a , equal to or different from each other, is selected from the group consisting of hydrogen and C 1 -C 6 hydrocarbon groups;
(A cat -2-B) hexamethylene tetramine of formula:

(A cat -3-A) carbamates of formula (C-1):

wherein R′ d is a C 1 -C 36 hydrocarbon group.

5. The method according to claim 3 , wherein the agent (A cat -4) is selected from the group consisting of (j) ammonium carboxylates optionally containing fluorine; (jj) ammonium sulfonates optionally containing fluorine; (jjj) ammonium phosphates optionally containing one or more fluorine-alkyl groups, phosphonates or sulfonates; (jv) ammonium salts of sulfuric acid, carbonic acid, nitric acid and phosphoric acid.

6. The method according to claim 2 , wherein the organotin compound is selected from the group consisting of allyl- propargyl-, triphenyl-, and allenyl-tin curatives, and tetraalkyl or tetraaryl tin compounds.

7. The method of claim 1 , wherein the agent (A) is selected from compounds possessing a plurality of groups having reactivity towards the nitrile groups of monomer (CS-N) and wherein the agent (A) is referred to as an agent (A func ), and is selected from the group consisting of:
(A func -1) bis-amino(thio)phenol compounds [aminophenol (AP)] of formula:

wherein:
A is a bond, —SO 2 —, —O—, —C(O)—, or a (fluoro)alkyl of 1 to 10 carbon atoms;
each of E, equal of different at each occurrence, is oxygen or sulphur, and wherein the amino and -EH groups are interchangeably in ortho, meta or para positions with respect to the group A;

(A func -2) aromatic tetraamine compounds [amine (TA)] of formula:

wherein:
A′ is a bond, —SO 2 —, —O—, —C(O)—, or a (fluoro)alkyl of 1 to 10 carbon atoms;
each of R N , equal to or different from each other, is a hydrogen atom or a C 1 -C 12 hydrocarbon group; and
the amino groups are interchangeably in ortho, meta or para positions with respect to the group A′,
(A func -3)′bis-amidoxime/amidine/amidrazone compounds of formula:

wherein R a1 is —OH or —H, and R a2 is H or NH 2 , and E is a C 1 -C 18 divalent group, optionally comprising fluorine atoms; and
(A func -4) bis-imidoylamidine compounds of formula:

wherein E b is a C 1 -C 18 divalent group, optionally comprising fluorine atoms, and R b is a C 1 -C 12 group, optionally fluorinated.

8. The method of claim 5 , wherein the agent (A func ) is 4,4′-[2,2,2-trifluoro-1-(trifluoromethyl)-ethylidene]bis(2-aminophenol), otherwise known as bis-aminophenol AF, having formula:

9. The method according to claim 7 , wherein
agent (A) is agent (A func -1), A is —C(CF 3 ) 2 — and each of E, equal to or different at each occurrence, is oxygen; or
agent (A) is agent (A func -2), A′ is —C(CF 3 ) 2 —, and each of R N , equal to or different from each other, is an aryl group.

10. The method of claim 1 , wherein marker (B) is selected from the group consisting of 4,4′-dibromooctafluorobiphenyl of formula:

and 4-bromobiphenyl of formula:

11. The method according to claim 1 , wherein composition (C) comprises:
marker (B), in an amount ranging from 0.10 to 10 phr, with respect to fluoroelastomer (A); and/or
agent (A), in an amount ranging from 0.10 to 10 phr, with respect to fluoroelastomer (A).

12. The method according to claim 11 , wherein composition (C) comprises:
marker (B), in an amount ranging from 0.25 to 6 phr, with respect to fluoroelastomer (A); and/or
agent (A), in an amount ranging from 0.25 to 5 phr, with respect to fluoroelastomer (A).

13. The method according to claim 1 , wherein the cure-site containing monomer of type (CS-N) is selected from the group consisting of:
(CS-N1) perfluorovinyl ethers containing nitrile groups of formula CF 2 ═CF—(OCF 2 CFX CN ) m —O—(CF 2 ) n —CN, with X CN being F or CF 3 , m being 0, 1, 2, 3 or 4; n being an integer from 1 to 12; and
(CS-N2) perfluorovinyl ethers containing nitrile groups of formula CF 2 ═CF—(OCF 2 CFX CN ) m′ —O—CF 2 —CF(CF 3 )—CN, with X CN being F or CF

Assignees

• Solvay Specialty Polymers It

Inventors

• Bossolo Stefano
• Fantoni Matteo
• Avataneo Marco
• Cox Michael J

Classifications

• H10W74/47

  comprising organic materials, e.g. plastics or resins · CPC title

• H10W74/016

  using moulds · CPC title

• H10W74/01

  Manufacture or treatment · CPC title

• C08K5/405

  Thioureas; Derivatives thereof · CPC title

• C08K5/03 Primary

  aromatic {, e.g. C6H5-CH2-Cl} · CPC title