×

Amorphous copolymers of perfluoro-2,2-dimethyl-1,3-dioxole

  • US 4,935,477 A
  • Filed: 06/05/1989
  • Issued: 06/19/1990
  • Est. Priority Date: 08/20/1981
  • Status: Expired due to Term
First Claim
Patent Images

1. An amorphous copolymer of 58-99 mole % of perfluoro-2,2-dimethyl-1,3-dioxole with complementary amounts of more than one comonomer selected from the class consisting of the following compounds:

  • (a) tetrafluoroethylene,(b) chlorotrifluoroethylene,(c) vinylidene fluoride,(d) hexafluoropropylene,(e) trifluoroethylene,(f) perfluoro(alkyl vinyl ethers) of the formula CF2 =CFORF, where RF is a normal perfluoroalkyl radical having 1-3 carbon atoms,(g) fluorovinyl ethers of the formula CF2 =CFOQZ, where Q is a perfluorinated alkylene radical containing 0-4 ether oxygen atoms, wherein the sum of the C and O atoms in Q is 2 to 10; and

    Z is a group selected from the class consisting of --COOR, --SO2 F, --CN, --COF, and --OCH3, where R is a C1 -C4 alkyl,(h) vinyl fluoride, and(i) (perfluoroalkyl)ethylene, Rf CH=CH2, where Rf is a C1 -C8 normal perfluoroalkyl radical;

    the glass transition temperature of the copolymer being at least 140°

    C.;

    the maximum mole percentage, Ma . . . Mi, of each comonomer in the copolymers being as follows;

    (a) for tetrafluoroethylene, Ma =35,(b) for chlorotrifluoroethylene, Mb =42,(c) for vinylidene fluoride, Mc =20,(d) for hexafluoropropylene, Md =15(e) for trifluoroethylene, Me =30(f) for CF2 =CFORF, Mf =30,(g) for CF2 =CFOQZ, Mg =20,(h) for vinyl fluoride, Mh =25, and(i) for Rf CH=CH2, Mi =10;

    and the amount of each comonomer other than perfluorodimethyl-1,3-dioxole being such that the sum, S, of the ratios of their mole percentages, ma . . . mi, to the maximum percentage of all such comonomers taken together, 42 mole %, is no larger than 1, as shown below;

    
    
    space="preserve" listing-type="equation">S=m.sub.a /42+m.sub.b /42+. . . +m.sub.i /42≦

    1.

View all claims
  • 2 Assignments
Timeline View
Assignment View
    ×
    ×