One-step process for rapid structure repair
This invention, relates to a one-step process for rapidly repairing structures. The process uses a binder comprising a polyisocyanate-terminated pre-polymer containing a divalent metal catalyst, and preferably a tertiary amine catalyst, which cures in the presence of moisture.
1 . A process for filling a space comprising:
adding a binder composition to said space, where said binder is packaged as one-part and said binder composition comprises a polyisocyanate pre-polymer containing free isocyanate groups and an effective catalytic amount of a divalent metal catalyst, under conditions where sufficient moisture is present to cure said binder composition after it has been added to said space.
2 . The process of claim 1 wherein said pre-polymer is the reaction product of a polyol and a polyisocyanate.
3 . The process of claim 2 wherein the content of free isocyanate groups in said pre-polymer is from 9 to 14 percent.
4 . The process of claim 3 wherein the polyol is selected from the group consisting of polyester polyols, polyether polyols, phenolic resole resins, and mixtures thereof.
5 . The process of claim 4 wherein the moisture is present in the space to be filled or is added to the space to be filled prior to adding said space-filling composition.
6 . The process of claim 5 wherein said binder composition further comprises an aggregate.
7 . The process of claim 6 wherein said space to be filled contains an aggregate.
8 . The process of claim 6 wherein the divalent metal catalyst is dibutyltindilaurate.
9 . The process of claim 7 wherein the divalent metal catalyst is dibutyltindilaurate.
10 . The process of claim 7 wherein the aggregate is selected from the group consisting of sand, crushed concrete, pea gravel, and rock.
11 . The process of claim 10 wherein the amount of divalent metal catalyst is from 0.2 to 0.6 parts by weight based upon the parts by weight of the polyisocyanate pre-polymer.
12 . The process of claim 11 wherein the amount of aggregate is from 50 to 95 parts by weight based upon 100 parts by weight of said binder.
13 . The process of claim 12 wherein space to be filled is an opening in an airport runway.
14 . The process of claim 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , or 13 also contains a catalytically effective amount of a tertiary amine catalyst.
15 . The process of claim 14 wherein the binder composition is solvent-free.
16 . The process of claim 15 wherein the tertiary amine is selected from the group consisting of 2,2′-dimorpholinodiethylether and N,N′-dimethylpiperazine.