# US 8,785,579 B2 · Linear perfluoropolyethers having an improved thermooxidative stability

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 8,785,579 B2
- Document ID: US8785579B2
- Status: Granted
- Kind: B2
- Application number: 13/028,859
- Filed: 2011-02-16
- Published: 2011-06-09
- Granted: 2014-07-22
- Earliest claimed: 2003-03-03
- Assignees: Solvay Solexis S.p.A.
- Applicants: Pier Antonio Guarda; Giuseppe Marchionni
- Inventors: Pier Antonio Guarda; Giuseppe Marchionni
- Web page: https://patentgrep.com/patent/US8785579B2

## CPC

- C08G 65/007: {containing fluorine}
- Y10T 428/3154: Of fluorinated addition polymer from unsaturated monomers
- C08G: MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

Linear perfluoropolyethers of formula: T-O (CF2O)n (CF2CF2O)m (CF2CF2CF2O)r (CF2CF2CF2CF2O)s-T1 (I) wherein n, m, r, s are integers such that the polymer number average molecular weight is comprised between 700 and 100,000 and the n/(n+m+r+s) ratio ranges from 0.05 to 0.40, and respective preparation process by addition of a peroxidic perfluoropolyether of formula (III): T4-O(CF2O)n, (CF2CF2O)m, (O)h-T5 (III) having a PO from 1.8 to 4, to a perfluoropolyether oil preheated at a temperature comprised between 150° C. and 250° C. and subsequent exhaustive fluorination of the obtained compound.

## Claims

### Claim 1

Linear perfluoropolyethers having the following structure formula:
T-O(CF2O)n(CF2CF2O)m(CF2CF2CF2O)r(CF2CF2CF2CF2O)s-T1 (I)
wherein:
T and T1, equal to or different from each other are selected from the group consisting of CF3—, CF3CF2—, C3F7—, C4F9—, CICF2— and —(CF2)COF wherein z=0, 1, 2, 3;
n, m, r, s are integers such that the number average molecular weight is comprised between 700 and 100,000;
the m/n ratio is comprised between 2 and 20;
the (r+s)/(n+m+r+s) ratio is comprised between 0.05 and 0.2;
the n/(n+m+r+s) ratio ranges from 0.05 to 0.40;
wherein the perfluorooxyalkylene units are statistically distributed along the polymeric chain, and wherein the total moles of the end groups comprise from 0.5% by moles to 50% by moles of “—(CF2)zCOF groups”.

### Claim 2 (depends on 1)

Perfluoropolyethers according to claim 1, wherein the number average molecular weight is in the range 1,500-20,000 (viscosity between 10 cSt and 1,000 cSt at 20° C.).

### Claim 3 (depends on 1)

Perfluoropolyethers according to claim 1, wherein the m/n ratio is comprised between 2 and 10.

### Claim 4 (depends on 1)

Perfluoropolyethers according to claim 1, wherein the (r+s)/(n+m+r+s) ratio is comprised between 0.07 and 0.2.

### Claim 5 (depends on 1)

Perfluoropolyethers according to claim 1, wherein the n/(n+m+r+s) ratio ranges from 0.1 to 0.3.

### Claim 6 (depends on 1)

Perfluoropolyethers according to claim 1, wherein the “—(CF2)zCOF end groups” are transformed into other functional groups.

### Claim 7 (depends on 6)

Perfluoropolyethers according to claim 6, wherein the functional end groups are selected from COOH, COOR (with R═CH3, C2H5, C3H7), aminic, alcoholic, aldehydic, salts, nitrilic, amidic functional groups.