Radiation curable compositions containing vinyl ether functional polysiloxanes and methods for the preparation

A method of making a curable coating composition comprising mixing:

• (A) a random siloxane polymer having its general formula selected from the group consisting of:
• ##STR22## wherein R is a monovalent hydrocarbon radical or halohydrocarbon radical having from 1 to 20 carbon atoms, R.sup.1 is a monovalent hydrocarbon or halohydrocarbon radical having from 1 to 8 carbon atoms or is a group having the formula --R.sup.2 OCH.dbd.CH.sub.2 wherein R.sup.2 is a divalent hydrocarbon or halohydrocarbon radical having from 1 to 20 carbon atoms, w is a mole percent of from greater than 0 to less than 100, x is a mole percent of from greater than 0 to less than 100, y is a mole percent of from greater than 0 to less than 100, z is a mole percent of from greater than 0 to less than 100, a is an integer of from 0 to 3, b is an integer of from 0 to 2, the sum of w+x+y, the sum of w+x+z, the sum of w+y+z, the sum of w+z, and the sum of w+y being equal to 100 mole percent, with the proviso that at least one --R.sup.2 OCH.dbd.CH.sub.2 group exists in each molecule;
• and
• (B) a photocleavable acid selected from the group consisting of an onium salt having its formula selected from the group consisting of R.sub.2 I.sup.+ MX.sub.n.sup.-, R.sub.3 S.sup.+ MX.sub.n.sup.-, R.sub.3 Se.sup.+ MX.sub.n.sup.-, R.sub.4 P.sup.+ MX.sub.n.sup.-, and R.sub.4.sup.N.sup.+ MX.sub.n.sup.- wherein each R is independently an organic radical having from 1 to 30 carbon atoms, and MX.sub.n.sup.- is a non-basic, non-nucleophilic anion and nitrobenzyl sulfonate esters.

A coated article prepared by a method comprising the steps of:

• (I) applying a composition to a solid substrate, said composition prepared by mixing:
• (A) a random siloxane polymer having its general formula selected from the group consisting of:
• ##STR25## wherein R is a monovalent hydrocarbon radical or halohydrocarbon radical having from 1 to 20 carbon atoms, R.sup.1 is a monovalent hydrocarbon or halohydrocarbon radical having from 1 to 8 carbon atoms or is a group having the formula --R.sup.2 OCH.dbd.CH.sub.2 wherein R.sup.2 is a divalent hydrocarbon or halohydrocarbon radical having from 1 to 20 carbon atoms, w is a mole percent of from greater than 0 to less than 100, x is a mole percent of from greater than 0 to less than 100, y is a mole percent of from greater than 0 to less than 100, z is a mole percent of from greater than 0 to less than 100, a is an integer of from 0 to 3, b is an integer of from 0 to 2, the sum of w+x+y, the sum of w+x+z, the sum of w+y+z, the sum of w+z, and the sum of w+y being equal to 100 mole percent, with the proviso that at least one --R.sup.2 OCH.dbd.CH.sub.2 group exists in each molecule;
• and
• (B) a photocleavable acid selected from the group consisting of an onium salt having its formula selected from the group consisting of R.sub.2 I.sup.+ MX.sub.n.sup.-, R.sub.3 S.sup.+ MX.sub.n.sup.-, R.sub.3 Se.sup.+ MX.sub.n.sup.-, R.sub.4 P.sup.+ MX.sub.n.sup.-, and R.sub.4 N.sup.+ MX.sub.n.sup.- wherein each R is independently an organic radical having from 1 to 30 carbon atoms, and MX.sub.n.sup.- is a non-basic, non-nucleophilic anion and nitrobenzyl sulfonate esters;
• and
• (II) exposing the coating to an energy source selected from the group consisting of (i) actinic radiation and (ii) actinic radiation in combination with heat in an amount sufficient to cure the coating.