×

Fluoroalkyl siloxane/vinyl copolymer dispersions and pressure-sensitive adhesives having improved solvent resistance prepared therefrom

  • US 5,482,991 A
  • Filed: 09/16/1994
  • Issued: 01/09/1996
  • Est. Priority Date: 09/18/1992
  • Status: Expired due to Term
First Claim
Patent Images

1. An adhesive comprising a cured adhesive composition, wherein the adhesive composition comprises:

  • a dispersion comprising the polymerization product of a mixture comprising;

    (a) about 5 to about 40 parts by weight of a fluoroalkyl siloxane of the formula ##STR3## wherein;

    R9 is independently selected from the group consisting of --CH2 CH2 Rf and -R7,Rf is a fluoroalkyl group independently selected from the group consisting of Cm F2m-1 and Cn F.sub.(2n+1)-q Hq,m is an integer ranging from about 1 to about 20;

    n is an integer ranging from about 1 to about 20;

    q is an integer ranging from about 0 to about 2n;

    x is an integer of about 11 or greater;

    the fluoroalkylsiloxane comprises 10 or greater --CH2 CH2 Rf groups;

    the fluoroalkylsiloxane comprises at least 1 R7 group;

    wherein R1, R2, R3, R4, R5, R6, and R8 are each independently selected from the group consisting of alkyl groups comprising about 1 to about 12 carbon atoms, aralkyl, alkaryl, alkoxy, alkylamino, hydroxyl, fluoroalkyl, and hydrogen; and

    R7 is an organic group having at least two carbon atoms wherein at least 1 olefinic moiety is contained within R7 ;

    wherein the ratio of R7 to --CH2 CH2 Rf is such that the mole percent of the olefinic moiety content contributed by R7 of the fluoroalkyl siloxane is between about 0.1 and about 4;

    (b) about 60 to about 95 parts by weight of free radically polymerizable monomer, wherein the free-radically polymerizable monomer comprises;

    (i) about 1 to about 20 percent by weight of free radically polymerizable polar monomer; and

    (ii) about 80 to about 99 percent by weight of free radically polymerizable non-polar monomer;

    wherein the weight percentages of (i) and (ii) are based upon the total weight of (i) plus (ii); and

    wherein the total weight of (a) plus (b) equals 100 parts by weight total;

    (c) about 0.1 to about 1 part by weight of a free radical initiator based upon 100 parts by weight total of (a) plus (b);

    (d) about 2 to about 10 parts by weight of a stabilizer based upon 100 parts by weight of total of (a) plus (b) wherein said stabilizer has a number average molecular weight ranging from about 8000 to about 25,000 and wherein said stabilizer is selected from the group consisting of;

    (i) a copolymer comprising (A) about 40 to about 60 parts by weight of monomer selected from the group consisting of vinyl esters of C1 to C8 monocarboxylic acids and C1 to C12 alkyl (meth)acrylates, and (B) about 60 to about 40 parts by weight of monomer selected from the group consisting of N-vinylpyrrolidone, acrylamide, N,N-dimethylacrylamide, N-vinylcaprolactam, and mixtures thereof wherein said copolymer stabilizer comprises 100 parts by weight total of the monomers of (i)(A) plus (i)(B); and

    (C) about 0.5 to about 5 weight percent of a chain transfer agent based upon the weight of the monomers of (i)(A) plus (i)(B);

    (ii) a macromonomer comprising the reaction product of the copolymer of (d)(i) wherein said chain transfer agent selected provides said copolymer with at least one functional group selected from the group consisting of --NH2, --COOH, --OH, and combinations thereof, with an endcapping agent selected from the group consisting of isocyanatoethyl methacrylate, alpha, alpha-dimethyl-meta-isopropenyl benzylisocyanate, vinyl azlactone, para(chloromethyl) styrene, glycidyl methacrylate, and mixtures thereof, wherein at least about 95% of the functional groups selected from the group consisting of --NH2, --COOH, --OH, and combinations thereof, of the copolymer are reacted with the endcapping agent; and

    (iii) mixtures thereof; and

    (e) about 30 to about 95 percent by weight of an organic solvent based upon the total weight of (a) plus (b) plus (c) plus (d) plus (e).

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×