Two-part curable composition
The present invention concerns a two-part curable composition comprising: ⋅ a first part (component A) comprising at least 51% by weight based on the total weight of the first part, of one or more cyanoacrylate monomer(s), provided that at least one of the cyanoacrylate monomer(s) is a cyanoacrylate monomer comprising a group —X—O—R b wherein X is a linear or branched alkylene radical optionally interrupted with one or several oxygen atom(s), and R b is an alkyl group; ⋅ a second part (component B) comprising: at least one Michael acceptor M selected from the group consisting of (meth)acrylic monomers, (meth)acrylic functionalized oligomers, (meth)acrylic functionalized resins, and mixtures thereof, provided that at least one of the Michael acceptor(s) M comprises at least one group of formula —O(CHR a —CH 2 O) n — where n ranges from 1 to 10 (Michael acceptor M1), and R a represents CH 3 or H; and a nucleophilic initiator.
1. A two-part curable composition comprising:
a first part (component A) comprising at least 51% by weight based on the total weight of the first part, of one or more cyanoacrylate monomer(s), provided that at least one of the cyanoacrylate monomer(s) is a cyanoacrylate monomer comprising a group —X—O—R b wherein X is a linear or branched alkylene radical optionally interrupted with one or several oxygen atom(s), and R b is an alkyl group; and
a second part (component B) comprising:
at least one Michael acceptor M selected from the group consisting of (meth)acrylic monomers, (meth)acrylic functionalized oligomers, (meth)acrylic functionalized resins, and mixtures thereof, provided that at least one of the Michael acceptor(s) M comprises at least one group of formula —O(CHR a —CH 2 O) n — where n ranges from 1 to 10 (Michael acceptor M1); and
a nucleophilic initiator;
wherein in the second part:
the total content of Michael acceptor(s) M1 is of at least 20% by weight based on the total weight of the second part; and
it does not comprise cyanoacrylate monomer.
2. The two-part curable composition according to claim 1 , wherein at least one of the one or more cyanoacrylate monomer(s) has the general formula (I):
wherein R is selected from the group consisting of C 1 -C 18 linear or branched alkyl, C 3 -C 20 alkoxyalkyl, trimethylsilylated C 1 -C 3 alkyl, furfuryl, allyl, cyclohexyl, and a group having the following formula: —R i —O—C(O)—C(R j )═CH 2 with R i being an organic moiety, and R j being H or CH 3 .
3. The two-part curable composition according to claim 2 , wherein at least one of the one or more cyanoacrylate monomer(s) has the formula (I) wherein R has the general formula (II):
wherein R 1 =CH 3 or H, R 2 =C 1 -C 4 linear or branched alkyl, and m ranges from 1 to 3.
4. The two-part curable composition according to claim 1 , wherein the total content of cyanoacrylate monomer(s) in the first part is higher than 60% by weight, based on the total weight of the first part.
5. The two-part curable composition according to claim 1 , wherein the first part of the composition comprises at least 20% by weight of at least one cyanoacrylate monomer comprising a group —X—O—R b wherein X is a linear or branched alkylene radical optionally interrupted with one or several oxygen atom(s), and R b is an alkyl group, based on the total weight of the first part of the composition.
6. The two-part curable composition according to claim 1 , wherein the cyanoacrylate monomer comprising a group —X—O—R b is characterized in that X is a linear alkylene comprising from 2 to 5 carbon atoms.
7. The two-part curable composition according to claim 1 , wherein the cyanoacrylate monomer comprising a group —X—O—R b is chosen from the group consisting of 2-methoxyethyl cyanoacrylate, 2-ethoxyethyl cyanoacrylate, 2-(1-methoxy) propyl cyanoacrylate, 2-(2′-methoxy)-ethoxyethyl-2″-cyanoacrylate, 2-(2′-ethoxy)-ethoxyethyl-2″-cyanoacrylate, 2-(2′-propyloxy)-ethoxyethyl-2″-cyanoacrylate, 2-(2′-butoxy)-ethoxyethyl-2″-cyanoacrylate, 2-(2′-pentyloxy)-ethoxyethyl-2″-cyanoacrylate, 2-(2′-hexyloxy)-ethoxyethyl-2″-cyanoacrylate, 2-(2′-methoxy)-propyloxypropyl-2″-cyanoacrylate, 2-(2′-ethoxy)-propyloxypropyl-2″-cyanoacrylate, 2-(2′-propyloxy)-propyloxypropyl-2″-cyanoacrylate, 2-(2′-butyloxy)-propyloxypropyl-2″-cyanoacrylate, 2-(2′-pentyloxy)-propyloxypropyl-2″-cyanoacrylate, 2-(2′-hexyloxy)-propyloxypropyl-2″-cyanoacrylate, 2-(2′-methoxy)-butyloxybutyl-2″-cyanoacrylate, 2-(2′-ethoxy)-butyloxybutyl-2″-cyanoacrylate, 2-(2′-butyloxy)-butyloxybutyl-2″-cyanoacrylate, 2-(3′-methoxy)-propyloxyethyl-2″-cyanoacrylate, 2-(3′-methoxy)-butyloxyethyl-2″-cyanoacrylate, 2-(3′-methoxy)-propyloxypropyl-2″-cyanoacrylate, 2-(3′-methoxy)-butyloxypropyl-2″-cyanoacrylate, 2-(2′-methoxy)-ethoxypropyl-2″-cyanoacrylate, 2-(2′-methoxy)-ethoxybutyl-2″-cyanoacrylate, and mixtures thereof.
8. The two-part curable composition according to claim 1 , wherein the first part of the composition contains at least one additive chosen from the group consisting of: a thixotropic agent, a thickening agent, a toughening agent, an accelerating agent, a per-compound, an adhesion promoter, a pigment, a colorant, a stabilizing agent, an antioxidant, a plasticizer, and mixtures thereof.
9. The two-part curable composition according to claim 1 , wherein the (meth)acrylic monomer is chosen from the group consisting of:
i. a compound of general formula (III):
a . CH 2 ═CR 3 (CO 2 R 4 ) (III),
wherein R 3 represents methyl or H, and R 4 is a hydrogen atom, a C 1 -C 8 linear or branched alkyl, a C 2 -C 6 linear or branched alkoxyalkyl, a furfuryl or a isobornyl group;
ii. a compound selected from the group consisting of: butanediol di(meth)acrylate, hexanediol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethyleneglycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, neopentylglycol diacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, bisphenol-A-diacrylate, bisphenol-A-dimethacrylate, ethoxylated bisphenol-A-diacrylate, propoxylated bisphenol-A-diacrylate, and mixtures thereof; and
iii. mixtures thereof.
10. The two-part curable composition according to claim 1 , wherein the second part of the composition comprises more than 30% by weight of Michael acceptor M based on the total weight of the second part.
11. The two-part curable composition according to claim 1 , wherein the Michael acceptor M1 is chosen from the group consisting of: ethoxylated bisphenol-A-di(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, polyethylene glycol diacrylate, propoxylated neopentyl glycol diacrylate, tetraethylene glycol diacrylate, triethylene glycol diacrylate, tripropylene glycol diacrylate, and mixtures thereof.
12. The two-part curable composition according to claim 1 , wherein the Michael acceptors M of the second part of the composition are Michael acceptors M1.
13. The two-part curable composition according to claim 1 , wherein the nucleophilic initiator is selected from the group consisting of:
organic bases;
salts of hard anions;
Ca 2+ , Zn 2+ or Mg 2+ salts of (meth)acrylic acid; and
mixtures thereof.
14. The two-part curable composition according to claim 1 , wherein the nucleophilic initiator in the second part of the composition is caffeine.
15. The two-part curable composition according to claim 1 , wherein the second part of the composition further contains at least one additive chosen from the group consisting of: a thixotropic agent, a thickening agent, a toughening agent, an accelerating agent, a per-compound, an adhesion promoter, a pigment, a colorant, a stabilizing agent, an antioxidant, a plasticizer, and mixtures thereof.
16. The two-part curable composition according to claim 1 , wherein the volume ratio first part:second part ranges from 1:1 to 10:1.
17. The two-part curable composition according to claim 1 , comprising:
a first part (component A) comprising:
at least 70% by weight based on the total weight of the first part, of one or more cyanoacrylate monomer(s), provided that at least one of the cyanoacrylate monomer(s) is a cyanoacrylate monomer comprising a group —X—O—R b wherein X is a linear or branched alkylene radical optionally interrupted with one or several oxygen atom(s), and R b is an alkyl group;
from 0.001% to 0.2% of stabilizing agent(s);
from 2% to 8% by weight of thixotropic agent(s);
from 2% to 8% by weight of thickening agent(s); and
a second part (component B) comprising:
at least 40% by weight of at least one Michael acceptor M selected from the group consisting of (meth)acrylic monomers, (meth)acrylic functionalized oligomers, (meth)acrylic functionalized resins, and mixtures thereof, provided that at least one of the Michael acceptor(s) M comprises at least one group of formula —O(CHR a —CH 2 O) n — where n ranges from 1 to 10 (Michael acceptor M1), and R a represents CH 3 or H; and
from 0.01% to 1% by weight of nucleophilic initiator(s) based on the total weight of the second part;
from 0% to 5% of thixotropic agent(s);
the second part being characterized in that the total content of Michael acceptor(s) M1 is of at least 40% by weight based on the total weight of the second part.
18. Syringe or cartridge or dispense heads comprising the two-part curable composition as defined in claim 1 .
19. Method for bonding substrates comprising the steps of:
applying a two-part curable composition as defined in claim 1 , to at least one of the substrates,
mating together the substrates for a time sufficient to permit an adhesive bond to form between the mated substrates; and
optionally heating the mated (and optionally clamped) substrates, to a temperature higher than 100° C.