ADHESION TO PLASTIC WITH BLOCK COPOLYMERS OBTAINED USING RAFT

1 . A process for preparing an aqueous coating composition comprising a block copolymer and a polymer P; wherein the block copolymer comprises at least blocks [A] x [B] y , where at least block [A] is obtained by a controlled radical polymerisation of at least one ethylenically unsaturated monomer via a reversible addition-fragmentation chain transfer (RAFT) mechanism;

where block [A] comprises:

i) 0 to 50 mol % of ethylenically unsaturated monomer units bearing crosslinking functional groups;

ii) 20 to 100 mol % of ethylenically unsaturated monomer units bearing water-dispersing functional groups;

iii) 0 to 50 mol % of ethylenically unsaturated monomers units selected from linear or branched C 1 to C 8 alkyl(meth)acrylate monomers;

iv) 0 to 5 mol % of ethylenically unsaturated monomer units bearing plastic adhesion promoting functional groups; and

v) 0 to 10 mol % of ethylenically unsaturated monomers units different from those from i), ii), iii)+iv);

where i), ii), iii), iv)+v) add up to 100%;

block [A] has an average degree of polymerisation x, where x is an integer from 3 to 80;

where block [B] comprises:

i) 0 to 5 mol % of ethylenically unsaturated monomer units bearing crosslinking functional groups;

ii) 0 to 15 mol % of ethylenically unsaturated monomer units bearing water-dispersing functional groups;

iii) 0 to 50 mol % of ethylenically unsaturated monomers units selected from linear or branched C 1 to 0 8 alkyl(meth)acrylate monomers;

iv) 20 to 100 mol % of ethylenically unsaturated monomer units bearing plastic adhesion promoting functional groups; and

v) 0 to 10 mol % of ethylenically unsaturated monomers units different from those from i), ii), iii)+iv);

where i), ii), iii), iv)+v) add up to 100%;

block [B] has an average degree of polymerisation y, where y is an integer>10, where y>x; and

where polymer P is obtained in the presence of the block copolymer by an emulsion polymerisation process, and comprises:

i) 0 to 20 wt % of ethylenically unsaturated monomer units bearing crosslinking functional groups;

ii) 0 to 15 wt % of ethylenically unsaturated monomer units bearing water-dispersing functional groups;

iii) 50 to 100 wt % of ethylenically unsaturated monomers units selected from linear or branched C 1 to 0 8 alkyl(meth)acrylate monomers;

iv) 0 to 50 wt % of ethylenically unsaturated monomer units bearing plastic adhesion promoting functional groups; and

v) 0 to 10 mol % of ethylenically unsaturated monomers units different from those from i), ii), iii)+iv);

where i), ii), iii), iv)+v) add up to 100%.

2 . A process according to claim 1 , where block [A] is obtained and/or obtainable by a controlled radical polymerisation of at least one ethylenically unsaturated monomer via a reversible addition-fragmentation chain transfer mechanism in solution in the presence of a control agent and a source of free radicals.

3 . A process according to claim 2 , in which the aqueous coating composition is capable of being applied to plastic substrates to form a coating thereon.

4 . A process according to claim 1 , where block [B] is obtained and/or obtainable by a controlled radical polymerisation of at least one ethylenically unsaturated monomer via a reversible addition-fragmentation chain transfer mechanism in solution in the presence of a control agent and a source of free radicals.

5 . A process according to claim 1 , wherein the ethylenically unsaturated monomer units bearing plastic adhesion promoting functional groups are selected from the group consisting of C 6 to C 20 (preferably C 6 to C 15 ) optionally substituted alkyl, cyclo alkyl and or aryl(meth)acrylate monomers, styrenic monomers, C 6 to C 20 (preferably C 6 to C 15 ) optionally substituted alkyl(meth)acrylamide monomers, vinylic monomers and mixtures thereof.

6 . A process according to claim 1 , where, when the substrate is polyolefinic, then component iv) of Block [B] comprises at least 50 mol ° A) of isobornyl(meth)acrylate.

7 . A process according to claim 1 , wherein the control agent is selected from the group consisting of dithioosters, thioethers-thiones, trithiocarbonates, dithiocarbamates, xanthates and mixtures thereof.

8 . A process according to claim 1 where polymer P is at least partially grafted to blocks [A][B].

9 . An aqueous coating composition obtained and/or obtainable by a process as claimed in claim 1 .

10 . An aqueous coating composition as claimed in claim 9 , which is capable of being applied to plastic substrates to form a coating thereon.

11 . A mixture of i) block copolymer comprising at least blocks [A] x [B] y , and ii) polymer P; where said mixture is obtained and/or obtainable by a process as claimed in claim 1 .

12 . A block copolymer-polymer comprising as components thereof i) block copolymer comprising at least blocks [A] x [B] y and ii) polymer P, where said blockcopolymer-polymer is obtained and/or obtainable by a process as claimed in claim 1 .

13 . A coating obtained and/or obtainable from a coating composition as claimed in claim 9 , and/or block copolymer-polymer.

14 . A substrate and/or article coated with a coating as claimed in claim 13 .

15 . A coated substrate and/or coated article as claimed in claim 14 , where the substrate and/or article comprises hydrophobic plastic.

16 . A method of coating a substrate and/or article comprising the steps of

i) applying a coating composition as claimed in claim 9 and/or block copolymer-polymer to the substrate and/or article; and

ii) drying the substrate and/or article to form a coating thereon.

17 . A method as claimed in claim 16 , where the substrate and/or article comprises hydrophobic plastic.

18 . A coated substrate and/or coated article obtained and/or obtainable by a method as claimed in claim 16 .

19 . Use of a coating composition as claimed in claim 9 and/or block copolymer-polymer to coat a substrate and/or article.

20 . Use of a coating composition as claimed in claim 9 and/or a substrate and/or article to provide coatings on at least one material selected from the group consisting of:

plastic substrates

foams;

surfaces having low surface energy;

hydrophobic substrates;

polyolefins;

any combinations thereof; and

any mixtures thereof.

21 . A use as claimed in claim 20 , where the coating is applied to at least one article selected from the group consisting of:

vehicles;

consumer electronic articles;

furniture;

household articles,

biomedical articles,

any combinations thereof and

any mixtures thereof.

22 . A method of manufacture of a coating composition as claimed in claim 9 and/or a substrate and/or article for the purpose of being used in at least one of the applications.