Selectively-Releasable Adhesives
In one embodiment, a selectively-releasable adhesive includes a copolymer formed from a multifunctional alcohol and a multifunctional carboxylic acid, wherein the copolymer has been cured the equivalent of up to approximately 20 hours at 120° C. and 100 milliTorr.
1 .- 40 . (canceled)
41 . A selectively-releasable adhesive comprising:
a cured copolymer formed from a multifunctional alcohol and a multifunctional carboxylic acid;
the adhesive exhibiting a peel strength of at least approximately 2 N/100 mm when tested according to ASTM D3330-78 PSTC-1 using a peel speed of 3.8 mm/s.
42 . The adhesive of claim 41 , wherein the multifunctional alcohol is selected from the group consisting of glycerol, monomeric carbohydrates, and small polyols.
43 . The adhesive of claim 41 , wherein the multifunctional alcohol is glycerol.
44 . The adhesive of claim 41 , wherein the multifunctional carboxylic acid is selected from the group consisting of diacids and triacids.
45 . The adhesive of claim 41 , wherein the multifunctional carboxylic acid is sebacic acid.
46 . The adhesive of claim 41 , wherein the copolymer is poly(glycerol-sebacate).
47 . The adhesive of claim 41 , wherein the adhesive has a peel strength of at least approximately 5 N/100 mm.
48 . The adhesive of claim 41 , wherein the adhesive has a peel strength of at least approximately 10 N/100 mm.
49 . The adhesive of claim 41 , wherein the adhesive has a peel strength of approximately 14 N/100 mm.
50 . The adhesive of claim 41 , wherein the copolymer has a crosslink density that does exceed 4 percent.
51 . The adhesive of claim 41 , wherein the copolymer has a crosslink density of approximately 1 to 3 percent.
52 . The adhesive of claim 41 , wherein the copolymer has a crosslink density that does not exceed approximately 0.05 moles per liter.
53 . The adhesive of claim 41 , wherein the copolymer has a crosslink density of approximately 0.01 to 0.04 moles per liter.
54 . The adhesive of claim 41 , wherein the multifunctional carboxylic acid has been purified multiple times.
55 . The adhesive of claim 41 , wherein the adhesive strength of the adhesive is significantly reduced when exposed to a solvent selected from the group consisting of alcohols, ketones, ethers, amides, sulfoxides, and esters.
56 . A selectively-releasable adhesive comprising:
a copolymer formed from a multifunctional alcohol and a multifunctional carboxylic acid, wherein the copolymer has been cured at an elevated temperature to increase the cohesiveness of the copolymer;
wherein the adhesive has inherent adhesive strength and therefore adheres to objects to which it is applied.
57 . The adhesive of claim 56 , wherein the copolymer has been cured in an oven at a temperature well above room temperature.
58 . The adhesive of claim 56 , wherein the copolymer has been cured at a temperature of approximately 120° C.
59 . The adhesive of claim 56 , wherein the copolymer has a crosslink density that does exceed 4 percent.
60 . The adhesive of claim 56 , wherein the copolymer has a crosslink density of approximately 1 to 3 percent.
61 . The adhesive of claim 56 , wherein the copolymer has a crosslink density that does not exceed approximately 0.05 moles per liter.
62 . The adhesive of claim 56 , wherein the copolymer has a crosslink density of approximately 0.01 to 0.04 moles per liter.
63 . The adhesive of claim 56 , wherein the multifuncational alcohol is glycerol and the multifuncational carboxylic acid is sebacic acid.