Fluoropolymer blend

Patent metadata

Field	Value
Publication number	US-2016200907-A1
Application number	US-201414914364-A
Country	US
Kind code	A1
Filing date	Aug 28, 2014
Priority date	Aug 30, 2013
Publication date	Jul 14, 2016
Grant date	—

Abstract

The present invention relates to the preparation of a thermoplastic fluoropolymer blend composition exhibiting improved mechanical properties upon fabrication. The fluoropolymer blend composite on is produced by blending an emulsion latex of fluoropolymer (A) with an emulsion latex of fluorinated copolymer (B). Copolymer (B) emulsion has a small particle size, super high MW, and a low degree of crystallinity. The blending of the latex emulsions results in a morphology with small particles of copolymer (B) uniformly distributed within a matrix of fluoropolymer (A) in a manner that could not be achieved by a mere melt blending of the tow components.

First claim

1 . A fluoropolymer composite blend comprising:
a) 20 to 99 weight percent of a continuous fluoropolymer (A) phase; and b) 1 to 80 weight percent of uniformly dispersed discrete domains of fluorinated copolymer (B), wherein fluoropolymer (B) has a) a heat of fusion of 0 to 20 J/g or a modulus of less than 35,000 psi by ASTM D790, b) a high viscosity of greater than 25 kpoise by ASTM D3835 at 235° C. and 100 −1 sec, and c) a small domain size of 20-1000 nm.

2 . The fluoropolymer composite blend of claim 1 , wherein fluoropolymer (A) and copolymer (B) each comprise at least 70 mole percent of vinylidene difluoride (VDF) monomer units.

3 . The fluoropolymer composite blend of claim 2 , wherein copolymer (B) is a copolymer comprising 70 mole percent or more of VDF and 1 to 30 mole percent of one or more monomers selected from chlorotrifluoroethylene (CTFE), tetrafluoroethylene (TFE), hexafluoropropylene (HFP), perfluoro propyle vinyl ether (PPVE) and perfluoro methyl vinyl ether (PMVE).

4 . The fluoropolymer composite blend of claim 1 , wherein copolymer (B) has a) a heat of fusion of 0 to 15 J/g or a modulus of less than 20,000 psi by ASTM D790, b) a high viscosity of 30 to 60 kpoise by ASTM D3835 at 235° C. and 100 −1 sec, c) a small domain size of 20-500 nm.

5 . The fluoropolymer composite blend of claim 4 , wherein copolymer (B) has a) a heat of fusion of 0 to 10 J/g or a modulus of less than 10,000 psi by ASTM D790, b) a high viscosity of 35 to 55 kpoise by ASTM D3835 at 235° C. and 100 −1 sec, c) a small domain size of 50-300 nm.

6 . The fluoropolymer composite blend of claim 1 , wherein fluoropolymer (A) comprises 25-95 weight percent and copolymer (B) comprises 5-75 weight percent of the blend.

7 . The fluoropolymer composite blend of claim 1 , wherein fluoropolymer (A) comprises 40-90 weight percent and copolymer (B) comprises 10-60 weight percent of the blend.

8 . A process for forming a fluoropolymer composite blend of claim 1 , comprising the steps of:
a) forming a fluoropolymer (A) latex; b) forming a fluorinated copolymer (B) latex, wherein fluoropolymer (B) has a) a heat of fusion of 0 to 20 J/g or a modulus of less than 35,000 psi by ASTM D790, b) a high viscosity of greater than 25 kpoise by ASTM D3835 at 235° C. and 100 −1 sec, c) blending fluoropolymer latex (A) and fluorinated copolymer (B) to form a stable latex containing as solids: 20-99 weight percent of fluoropolymer latex (A) and 1 to 80 weight percent of fluorinated copolymer (B); d) isolating the polymer solids of the blend of c); to form a composite blend having a continuous phase of fluoropolymer (A) and small domains of copolymer (B) wherein said domains have a size of 20-1000 nm.

9 . The process of claim 8 , wherein said polymer is isolated in step d) by spray drying.

10 . The process of claim 9 , further comprising as step e) pelletizing the spray-dried polymer composite blend.

11 . an article comprising the polymer composite blend of claim 1 .

12 . The article of claim 11 , wherein said article is selected from the group consisting of: pipes, tubes, sheets, cable jacketing, rods, molded articles, melt-cast single or multi-layer films, and fibers.

Assignees

• Arkema Inc

Inventors

• Amin-Sanayei Ramin
• O'Brien Gregory S
• Zerafati Saeid

Classifications

• C08L2203/30

  used for thermoforming · CPC title

• C08L27/16 Primary

  Homopolymers or copolymers or vinylidene fluoride · CPC title

• B29C48/04

  Particle-shaped (making granules B29B9/00) · CPC title

• B29K2027/12

  containing fluorine · CPC title

• B29L2031/00

  Other particular articles · CPC title