Adhesives and related methods
Cure in place pressure sensitive adhesive compositions are described that comprise one or more of a bodying component, a structural diluent, a radical diluent as well as additives such as crosslinkers, external catalysts, photoinitiators and stabilizers/process aids. The bodying component can be acrylic or non-acrylic.
1. A cure in place composition comprising:
a pressure sensitive adhesive comprising 50-80 wt % of an acrylic base polymer having a molecular weight (Mw) of 250,000-750,000;
20-40 wt % of at least one structural diluent containing crosslinkable functionality for crosslinking in place;
0-0.5 wt % of at least one metal chelate crosslinker;
0.01-2 wt % of a curative; and
0-10 wt % of stabilizer/process aid,
wherein the pressure sensitive adhesive converts to a structural adhesive upon exposure to a stimulus, and
wherein the stimulus is selected from the group consisting of radiation, heat, moisture, pressure, ultrasound, chemical exposure, and combinations thereof.
2. A cure in place composition comprising:
a pressure sensitive adhesive comprising 50-80 wt % of an acrylic base polymer having a molecular weight (Mw) of 250,000-750,000;
20-40 wt % of at least one structural diluent containing crosslinkable functionality for crosslinking in place;
0-30 wt % of at least one acrylic-epoxy functional component;
0-0.5 wt % of at least one metal chelate crosslinker;
0.01-2 wt % of curative; and
0-10 wt % of stabilizer/process aid,
wherein the pressure sensitive adhesive converts to a structural adhesive upon exposure to a stimulus, and
wherein the stimulus is selected from the group consisting of radiation, heat, moisture, pressure, ultrasound, chemical exposure, and combinations thereof.
3. A cure in place liquid composition comprising:
a pressure sensitive adhesive comprising 70-80 wt % of a bodying component comprising an acrylic base polymer having a molecular weight (Mw) of 15,000-250,000;
15-20 wt % of at least one structural diluent containing crosslinkable functionality for crosslinking in place;
0.01-5 wt % of a photoinitiator; and
0-10 wt % stabilizer/process aid,
wherein the pressure sensitive adhesive converts to a structural adhesive upon exposure to a stimulus, and
wherein the stimulus is selected from the group consisting of radiation, heat, moisture, pressure, ultrasound, chemical exposure, and combinations thereof.
4. The cure in place liquid composition of claim 3 wherein the acrylic backbone base polymer has a Mw of 18,000 to 70,000.
5. The cure in place composition of claim 1 wherein the curative is a catalyst, and the stabilizer/process aid is 1,4,4-trimethyl-2,3-diazabicyclo-[3.2.2]-non-2-ene-2,3-dioxide.
6. A construction comprising:
a substrate; and
the cure in place composition of claim 1 disposed on the substrate.
7. A construction comprising:
a substrate; and
the cure in place composition of claim 2 disposed on the substrate.
8. A construction comprising:
a substrate; and
the cure in place liquid composition of claim 3 disposed on the substrate.
9. The cure in place liquid composition of claim 1 wherein the structural diluent is selected from the group consisting of 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate (S-21), Bis[(3,4-epoxycyclohexyl)methyl]adipate (S-28), difunctional bisphenol A/epichlorohydrin derived liquid epoxy resin (Epon 828), Bisphenol A epoxy resin having a weight per epoxide of 235-263 g/eq as measured by ASTM D1652 (Epon 834), beta-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (A-186), gamma-glycidoxypropyltrimethoxysilane (A-187), glycidyl ester of neodecanoic acid (EP-10), isocyanate-functional urethane acrylate (Desmolux D100), isocyanate-bearing urethane acrylate (Desmolux D200), aliphatic polyisocyanate (low-viscosity hexamethylene diisocyanate (HDI) biuret) (Desmodur N3200), aliphatic polyisocyanate (hexamethylene diisocyanate (HDI) biuret) (Desmodur N100), aliphatic polyisocyanate (hexamethylene diisocyanate (HDI) trimer) (Desmodur N3300), poly(propylene oxide) (PPO) oligomer having a molecular weight (Mw) of less than 5,000 daltons, trimethylolpropane oxetane (TMPO), poly(ethylene oxide) (PEO) oligomer having a molecular weight (Mw) of less than 5,000 daltons, ethyl hexyl oxetane (2EH oxetane), difunctional oxetane, trimethylolpropane triacrylate (TMPTA) of the following formula (5), tripropyleneglycol diacrylate (TPGDA) of the following formula (6), ethoxylated bisphenol A diacrylate of the following formula (7) in which n+m=3, ethoxylated trimethylolpropane triacrylate of the following formula (8), bisphenol A diglycidyl ether diacrylate of the following formula (9), 1,2-cyclic ethers, 1,3-cyclic ethers, 1,4-cyclic ethers, anhydrides, lactones, lactams, cyclic ethers, siloxanes, oxazolines, oxalidines, and bismaleimides;
10. The cure in place liquid composition of claim 1 wherein the acrylic base polymer is a pre-polymerized acrylic backbone base polymer.
11. The cure in place liquid composition of claim 2 wherein the acrylic base polymer is a pre-polymerized acrylic backbone base polymer.
12. The cure in place liquid composition of claim 3 wherein the acrylic base polymer is a pre-polymerized acrylic backbone base polymer.
13. The cure in place liquid composition of claim 1 wherein the glass transition temperature of the acrylic base polymer is less than 0° C.
14. The cure in place liquid composition of claim 10 wherein the pre-polymerized acrylic backbone base polymer is completely/fully polymerized.
15. The cure in place composition of claim 10 wherein the pre-polymerized acrylic backbone base polymer does not contain any ethylenic unsaturation or acrylate unsaturation along the polymer chain.
16. The cure in place composition of claim 11 wherein the pre-polymerized acrylic backbone base polymer does not contain any ethylenic unsaturation or acrylate unsaturation along the polymer chain.
17. The cure in place liquid composition of claim 12 wherein the pre-polymerized acrylic backbone base polymer does not contain any ethylenic unsaturation or acrylate unsaturation along the polymer chain.