Polymers of hexafluoropropene oxide and process of making

• US 6,034,207 A
• Filed: 04/01/1999
• Issued: 03/07/2000
• Est. Priority Date: 04/01/1998
• Status: Expired due to Term

• Current Assignee: Shin-Etsu Chemical Company Limited
• Original Assignee: Shin-Etsu Chemical Company Limited
• Inventors: Matsuda, Takashi, Sato, Shinichi, Koike, Noriyuki
• Primary Examiner(s): Acquah, Samuel A.
• Application Number:
  US09/285,008
• Time in Patent Office: 341 Days
• Field of Search: 528/26, 528/70, 528/341, 528/402, 528/425, 525/180, 525/187, 525/190, 525/191, 568/615, 524/755, 524/757, 524/792, 524/795, 524/839, 524/845
• US Class Current: 528/402
• CPC Class Codes: C08G 65/226 containing fluorine

Abstract

A hexafluoropropene oxide polymer of formula (1) having a dispersity Mw/mn of up to 1.10 is useful as a raw material for liquid rubber. In formula (1), R is --COF, --I, --Br, --CH₂ OH, --CH₂ OCH₂ CH═CH₂, --COOR¹ or --CONR² R³ wherein R¹, R² and R³ are independently hydrogen or monovalent C_1-20 hydrocarbon groups which may contain N, O, Si or S, or R² and R³ form a ring with the N atom, Rf is a C_1-6 perfluoroalkylene group or a C_2-10 perfluorooxyalkylene group, and x+y=30 to 400. ##STR1##

Claims

1. A hexafluoropropene oxide polymer represented by the following general formula (1):

##STR29## wherein R is --COF, --I, --Br, --CH₂ OH, --CH₂ OCH₂ CH═

CH₂, --COOR¹ or --CONR² R³ wherein R¹, R² and R³ are independently hydrogen or monovalent hydrocarbon groups of 1 to 20 carbon atoms which may contain a nitrogen, oxygen, silicon or sulfur atom, R² and R³ may be the same or different, or R² and R³, taken together, form a ring with the nitrogen atom,

Rf is a perfluoroalkylene group of 1 to 6 carbon atoms or a perfluorooxyalkylene group of 2 to 10 carbon atoms having an ether bond, which may contain a cyclic structure, and

x and y are positive numbers and the sum of x and y is from 30 to 400,

said polymer having a dispersity Mw/Mn of up to 1.10, the dispersity being given as a weight average molecular weight (Mw) divided by a number average molecular weight (Mn).

2. The hexafluoropropene oxide polymer of claim 1 having a number average degree of polymerization of 30 to 400.

5. A process for preparing a hexafluoropropene oxide polymer, comprising the steps of:

dissolving in an aprotic polar solvent having at least 4 ether bonds a polymerization initiator represented by the following general formula (2);

space="preserve" listing-type="equation">CsOCF.sub.2 --Rf--CF.sub.2 OCs (2)

wherein Rf is a perfluoroalkylene group of 1 to 6 carbon atoms or a perfluorooxyalkylene group of 2 to 10 carbon atoms having an ether bond, which may contain a cyclic structure, to form a polymerization initiator solution,

treating the polymerization initiator solution with a perfluoroolefin at a temperature higher than a polymerization temperature,

adding a hydrocarbon solvent having 1 to 3 ether bonds in a molecule to the polymerization initiator solution before or after the treatment, and

feeding hexafluoropropene oxide to the treated polymerization initiator solution for effecting polymerization of hexafluoropropene oxide at the polymerization temperature,

thereby yielding a reaction product containing as the main component a hexafluoropropene oxide polymer of formula (1) as set forth in claim 1 wherein R is --COF, said reaction product having a dispersity Mw/Mn of up to 1.10, the dispersity being given as a weight average molecular weight (Mw) divided by a number average molecular weight (Mn).

6. The process of claim 5 wherein the reaction product consists essentially of a polymer represented by the following general formula (1a):

##STR31## wherein Rf is a perfluoroalkylene group of 1 to 6 carbon atoms or a perfluorooxyalkylene group of 2 to 10 carbon atoms having an ether bond, which may contain a cyclic structure, x and y are positive numbers and the sum of x and y is from 30 to 400,

said reaction product containing n moles of FOC--CF(CF₃)-- terminal groups and m moles of CF₃ CF₂ CF₂ -- terminal groups in a relationship satisfying 2m/(m+n)<

0.15.

7. The process of claim 5 wherein the polymerization temperature is in the range of -45°

C. to -30°

C.

3. A hexafluoropropene oxide polymer product obtained by feeding hexafluoropropene oxide to a compound represented by the following general formula (2):

space="preserve" listing-type="equation">CsOCF.sub.2 --Rf--CF.sub.2 OCs (2)

wherein Rf is a perfluoroalkylene group of 1 to 6 carbon atoms or a perfluorooxyalkylene group of 2 to 10 carbon atoms having an ether bond, which may contain a cyclic structure,

said polymer product consisting essentially of a polymer represented by the following general formula (1a);

##STR30## wherein Rf is as defined above, x and y are positive numbers and the sum of x and y is from 30 to 400,

said polymer product containing n moles of FOC--CF(CF₃)-- terminal groups and m moles of CF₃ CF₂ CF₂ -- terminal groups in a relationship satisfying 2m/(m+n)<

0.15,

said polymer product having a dispersity Mw/Mn of up to 1.10, the dispersity being given as a weight average molecular weight (Mw) divided by a number average molecular weight (Mn).

4. The hexafluoropropene oxide polymer product of claim 3 having a number average degree of polymerization of 30 to 400.