METHODS OF SYNTHESIZING MULTI-HYDROGEN BONDING OLIGOMERS

1 . A method for synthesizing an oligomer mixture with one or more moieties capable of forming a multi-hydrogen bonding dimer, the method comprising the steps of:

(1) providing an intermediate reaction product which is the reaction product of a multi-hydrogen bonding group precursor compound having an amino group with a multifunctional isocyanate compound;

(2) adding a polyol component directly to the intermediate reaction product to yield an oligomer mixture comprising one or more multi-hydrogen bonding groups;

(3) further reacting the oligomer mixture with an isocyanate-reactive compound also optionally having at least one additional reactive group to yield one or more multi-hydrogen bonding oligomers;

wherein a quantity of unreacted isocyanate groups remains present in the intermediate reaction product after completion of step (1) and in the oligomer mixture after completion of step (2); and

wherein, relative to all reagents used in the synthesis of the one or more multi-hydrogen bonding oligomers, solvents comprise less than 50% of the total by weight.

2 . The method according to claim 1 , wherein no separation, distillation, or isolation of the of the intermediate reaction product occurs prior to the adding step (2).

3 . The method according to claim 1 , wherein no separation, distillation, or isolation of the oligomer mixture occurs prior to the further reacting step (3).

4 . The method according to claim 1 , wherein the method is a continuous or one-pot process.

5 . The method according to claim 1 , wherein the oligomer mixture and/or the one or more multi-hydrogen bonding oligomers comprise less than 40 wt. % of solvents.

6 . The method according to claim 1 , wherein the multi-hydrogen bonding group precursor compound having an amino group comprises 2 amino-4-hydroxy-6-alkyl-pyrimidines.

7 . The method according to claim 1 , wherein the multifunctional isocyanate compound comprises trimethylhexamethylene diisocyanate, 2,4-tolylenediisocyanate, 2,6-tolylenediisocyanate, isophorone-diisocyanate, diphenylmethane-4,4′-diisocyanate, hexamethylenediisocyanate, cyclohexanediisocyanate, dicyclohexylmethylene diisocyanate, phenylenediisocyanate, naphthalene diisocyanate, triphenylmethanetriisocyanate, toluene-2,4,6-triisocyanate, or mixtures thereof.

8 . The method according to claim 1 , wherein the polyol component comprises a polyether polyol, a polyester polyol, a poly(dimethylsiloxane), a disulfide polyol, or mixtures thereof.

9 . The method according to claim 1 , wherein the isocyanate-reactive compound possesses a hydroxyl, amino, or thiol group and further comprises triols or hydroxyl-functional (meth)acrylate monomers.

10 . The method according to claim 1 , wherein step (1) is preceded by the step of reacting the multi-hydrogen bonding group precursor compound having an amino group with the multifunctional isocyanate compound at a temperature of between 110-160° C. until mixture becomes clear.

11 . The method according to claim 1 , wherein

step (2) is carried out at a temperature of between 60-120° C. for a mixing duration until all or substantially all hydroxyl groups from the polyol component have reacted with the multifunctional isocyanate compound, as determined according to an NCO titration method.

12 . The method according to claim 1 , wherein step (2) comprises adding the polyol component directly to the intermediate reaction product in the presence of a catalyst and/or an inhibitor.

13 . The method according to claim 1 , wherein step (3) comprises further reacting the oligomer mixture in the presence of a catalyst and/or an inhibitor.

14 . The method according to claim 1 , wherein step (3) comprises removing nitrogen protection and controlling the reaction at a temperature of between 60-120° C. for a mixing duration until reaction completion, as determined according to an NCO titration method.

15 . The method according to claim 12 , wherein the catalyst comprises organometallic tin, bismuth, zinc, lead, copper, iron, dibutyltin dilaurate, dibutyltin diacetate, stannous octoate, bismuth octoate, bismuth neodecanoate, zinc 2-ethylhexanote, or lead octoate, or combinations thereof;

and/or

wherein the inhibitor comprises phenolic inhibitors.

16 . The method according to claim 1 , wherein a ratio of the equivalents of the multi-hydrogen bonding group precursor compound having an amino group to the

a. the multifunctional isocyanate compound is from 1:3 to 1:8;

b. the polyol component is from 1:1.5 to 1:6;

c. the isocyanate-reactive compound also optionally having at least one additional reactive group is from 1:0.5 to 1:1.5.

17 . The method according to claim 1 , wherein the one or more multi-hydrogen bonding oligomers is according to formula (VII):

[UPy-(D m -U-D m ) (2+q )]-[A(G) (n−1) -D m ] k -Z  (VII);

wherein

UPy represents a UPy group, wherein the UPy group is a 2-ureido-4-pyrimidinone;

U represents —NHC(O)E- or -EC(O)NH—, wherein E is O, NH, N(alkyl), or S;

q is a number greater than or equal to 0 and less than or equal to 10;

k is a number from 0 to 20;

A is selected from carbon and nitrogen;

n is 2 or 3, wherein when A is an sp3 carbon, n=3, and when A is an sp2 carbon or a nitrogen, n=2;

m is an integer from 0 to 500;

D is, for each occurrence of m, a divalent spacer independently chosen from —O—,

—C(O)—, -Aryl-, —C≡C—, —N═N—, —S—, —S(O)—, —S(O)(O)—, —(CT 2 ) i -, —N(T)-, —Si(T) 2 (CH 2 ) i —, —(Si(T) 2 O) i —, —C(T)═C(T)-, —C(T)═N—, —C(T)=, —N═, or combinations thereof;

wherein

for each instance in D of a single bond, a single bond is connected thereto, and

for each instance in D of a double bond, a double bond is connected thereto;

wherein

each T is selected for each occurrence from single valent units including hydrogen, F, Cl, Br, I, C 1 -C 8 alkyl, C 1 -C 8 alkoxy, substituted amino, or substituted aryl;

wherein each T can also be selected from divalent D m and connects to another divalent T that's also selected from D m and form a ring structure; and

i is an integer from 1-40;

Z is chosen from a hydrogen, acryloyloxy, methacryloyloxy, hydroxy, amino, vinyl, alkynyl, azido, silyl, siloxy, silylhydride, thio, isocyanato, protected isocyanato, epoxy, aziridino, carboxylic acid, hydrogen, F, Cl, Br, I, or maleimido group; and

G is, for each occurrence of n, independently selected from hydrogen, -D m -Z, or a self-healing moiety according to the following structure (VII-b):

(Z-D m ) j -X-D m -  (VII-b);

wherein

X is a multi-hydrogen bonding group, a disulfide group, or a urea group;

j=1 when X is divalent, and j=0 when X is monovalent.

18 . The method according to claim 1 , wherein the one or more multi-hydrogen bonding oligomers possesses one of the following structures (XI), (XII), (XIII), (XVIII), (XXI), or (XXXIV):

or mixtures thereof; and

wherein n is greater than 0 and may be any number provided that the MW theo of the oligomer is maintained to less than 5000 g/mol.

19 . The method according to claim 1 , wherein the one or more multi-hydrogen bonding oligomers possesses one of the following structures (IX), (X), (XIV)-(XVII), (XXII), (XXIII), (XXV)-(XXVII), (XXIX), (XXX), (XXXII), (XXXIII), (XXXV)-(XXXVII), or (XL):

or mixtures thereof;

wherein n and m are greater than 0 and may be independently any number provided that the MW theo of the oligomer is maintained to less than 5000 g/mol;

wherein, for each occurrence of an acrylate group above, a methacrylate group alternatively may be substituted therefor, and for each occurrence of a methacrylate group above, an acrylate group alternatively may be substituted therefor.

20 . The method according to claim 1 , wherein the one or more multi-hydrogen bonding oligomers comprises the following structure (XXXI):

wherein, for each occurrence of an acrylate group above, a methacrylate group alternatively may be substituted therefor, and for each occurrence of a methacrylate group above, an acrylate group alternatively may be substituted therefor.