Moisture curable hot melt sealant composition including silane functional polyurethane
A moisture curable hot melt sealant composition that includes a silane-functional polyurethane that is free of isocyanate groups, a thermoplastic elastomer having a weight average molecular weight of at least 100,000 grams per mole and being derived from 0% by weight to no greater than 30% by weight styrene, based on the weight of the thermoplastic elastomer, the thermoplastic elastomer being selected from the group consisting of butyl rubber, ethylene-propylene rubber, ethylene-propylene diene rubber, thermoplastic polyolefin elastomer, styrene block copolymer, and combinations thereof, a first tackifying agent that includes from 0% by weight to less than 15% by weight aromaticity based on the weight of the tackifying agent, the first tackifying agent being selected from the group consisting of aliphatic tackifying agent, aromatic-modified aliphatic tackifying agent, cycloaliphatic tackifying agent, aromatic-modified cycloaliphatic tackifying agent, and combinations thereof, a liquid butene component selected from the group consisting of polyisobutylene, polyisobutene, polybutene, and combinations thereof, and optionally a second rosin-based tackifying agent.
1. A moisture curable hot melt sealant composition comprising:
from 1% by weight to no greater than 12% by weight of a silane-functional polyurethane that is free of isocyanate groups;
at least 10% by weight of a thermoplastic elastomer having a weight average molecular weight of at least 100,000 grams per mole (g/mol) and being derived from 0% by weight to no greater than 30% by weight styrene, based on the weight of the thermoplastic elastomer, the thermoplastic elastomer being selected from the group consisting of butyl rubber, polyisobutylene rubber, ethylene-propylene rubber, ethylene-propylene diene rubber, thermoplastic polyolefin elastomer, styrene block copolymer, and combinations thereof;
at least 10% by weight of a first tackifying agent that includes from 0% by weight to less than 15% by weight aromaticity based on the weight of the first tackifying agent, the first tackifying agent being selected from the group consisting of aliphatic tackifying agent, aromatic-modified aliphatic tackifying agent, cycloaliphatic tackifying agent, aromatic-modified cycloaliphatic tackifying agent, and combinations thereof;
a second rosin-based tackifying agent; and
a liquid butene component selected from the group consisting of polyisobutylene, polyisobutene, polybutene, and combinations thereof.
2. The sealant composition of claim 1 further comprising a thermoplastic polyalphaolefin having a weight average molecular weight of less than 100,000 g/mol, the thermoplastic polyalphaolefin being selected from the group consisting of silane functional amorphous polyalphaolefin, amorphous polyalphaolefin, and combinations thereof.
3. The sealant composition of claim 1 comprising from 2% by weight to 30% by weight of the liquid butene component.
4. The sealant composition of claim 1 , wherein the thermoplastic elastomer comprises butyl rubber.
5. The sealant composition of claim 1 comprising at least 10% by weight of the butyl rubber.
6. The sealant composition of claim 1 further comprising filler.
7. The sealant composition of claim 6 , wherein the filler comprises talc.
8. The sealant composition of claim 1 , wherein the thermoplastic elastomer comprises the styrene block copolymer and the styrene block copolymer is selected from the group consisting of styrene-butadiene-styrene, styrene-isoprene-styrene, styrene-ethylene/propylene-styrene, styrene-ethylene/butene-styrene block copolymer, and combinations thereof.
9. The sealant composition of claim 2 comprising at least 10% by weight of the thermoplastic polyalphaolefin.
10. The sealant composition of claim 1 further comprising from 10% by weight to 30% by weight of a thermoplastic silane functional amorphous polyalphaolefin having a weight average molecular weight of less than 100,000 g/mol.
11. The sealant composition of claim 1 , comprising
from 1% by weight to 10% by weight of the silane functional polyurethane,
from 10% by weight to 30% by weight of the thermoplastic elastomer, and
no greater than 40% by weight total tackifying agent.
12. The sealant composition of claim 1 , comprising
from 1% by weight to 10% by weight of the silane functional polyurethane,
from 10% by weight to 30% by weight of the thermoplastic elastomer,
from 10% by weight to 25% by weight of the first tackifying resin, and
from 5% by weight to 20% by weight of the second rosin-based tackifying agent.
13. The sealant composition of claim 12 further comprising at least 5% by weight amorphous polyalphaolefin.
14. The sealant composition of claim 12 further comprising from 10% by weight to 30% by weight silane functional amorphous polyalphaolefin.
15. The sealant composition of claim 1 , wherein the sealant composition exhibits a moisture vapor transmission rate of no greater than 25 g/m 2 /day.
16. The sealant composition of claim 1 , wherein the sealant composition exhibits a property selected from the group consisting of
at least 100% elongation,
a shear adhesion failure temperature of at least 70° C.,
a 60° C. dead load of at least 200 minutes, and
combinations thereof.
17. A moisture curable hot melt sealant composition comprising:
from 1% by weight to no greater than 10% by weight of a silane-functional polyurethane that is free of isocyanate groups;
at least 10% by weight of a thermoplastic elastomer having a weight average molecular weight of at least 100,000 g/mol and being derived from 0% by weight to no greater than 30% by weight styrene, based on the weight of the thermoplastic elastomer, the thermoplastic elastomer being selected from the group consisting of butyl rubber, polyisobutylene rubber, ethylene-propylene rubber, ethylene-propylene diene rubber, thermoplastic polyolefin elastomer, styrene block copolymer, and combinations thereof;
at least 10% by weight of a first tackifying agent that includes from 0% by weight to less than 15% by weight aromaticity based on the weight of the first tackifying agent, the first tackifying agent being selected from the group consisting of aliphatic tackifying agent, aromatic-modified aliphatic tackifying agent, cycloaliphatic tackifying agent, aromatic-modified cycloaliphatic tackifying agent, and combinations thereof; and
a liquid butene component selected from the group consisting of polyisobutylene, polyisobutene, polybutene, and combinations thereof.
18. The sealant composition of claim 17 , wherein the sealant composition exhibits a property selected from the group consisting of
a peel strength of at least 20 pounds per linear inch (pli) when tested according to the 180 Degree Peel Adhesion test method using a glass substrate and a black line stainless steel substrate,
a peel strength of at least 50 pli when tested according to the Climbing Drum Peel test method using a glass substrate and a black line stainless steel substrate,
a peel strength to polyvinyl chloride of at least 12 pli when tested according to the 180 Degree Peel Adhesion test method using a polyvinyl chloride substrate and a 30 mesh steel screen substrate,
a peel strength of at least 20 pli to a polar substrate having a surface energy greater than 32 dynes/cm when tested according to the 180 Degree Peel Adhesion test method using a glass substrate and a polar substrate having a surface energy greater than 32 dynes/cm, and combinations thereof.
19. An insulating glass unit comprising:
a first pane of glass;
a second pane of glass;
a spacer disposed between the first pane of glass and the second pane of glass, and
the sealant composition of claim 1 in contact with the first pane of glass, the second pane of glass, and the spacer.
20. A window comprising:
an insulating glass unit comprising
a first pane of glass,
a second pane of glass,
a spacer disposed between the first pane of glass and the second pane of glass, and
a first sealant composition in contact with the first pane of glass, the second pane of glass, and the spacer,
a frame; and
a second sealant composition in contact with the insulating glass unit and the frame, the second sealant composition comprising the sealant composition of claim 17 .