Curable polyurethane prepolymer composition
The present invention relates generally to a curable polyurethane prepolymer composition comprising polyurethane prepolymer obtained by the reaction of toluene diisocyanate (TDI) and at least one polyol and an ortho alkyl disubstituted dianiline, preferably 4,4′-methylene-bis-(3-chloro-2,6-diethylaniline) (MCDEA), wherein 50 to 100 wt % of the at least one polyol is at least one polycarbonate polyol.
1 . A curable polyurethane prepolymer composition, comprising:
a polyurethane prepolymer obtained by reacting components comprising a toluene diisocyanate and a polyol; and
an ortho alkyl disubstituted dianiline of formula (I)
RI independently being a linear C 1 -C 6 alkyl, branched C 1 -C 6 alkyl, R2 being hydrogen or halogen, and A being —O—, —CH 2 —, —C(CH 3 ) 2 , —SO 2 —, or —CO 2 (CH 2 ) n O 2 C—, with n being 1, 2, 3, 4, 5 or 6.
wherein the polyol comprises a polycarbonate polyol in a range of from 50 to 100 w wt. %, based on total polyol weight, and
wherein the polyurethane prepolymer comprises less than 0.1 wt. % of free TDI monomer, based on a total weight of the polyurethane prepolymer.
2 . The composition of claim 1 , wherein, in the ortho alkyl disubstituted dianiline of formula (I),
R1 is independently a linear C 1 -C 6 alkyl,
R2 is either hydrogen or halogen, and
A is —CH 2 — or —C(CH 3 ) 2 .
3 . The composition of claim 1 , wherein the ortho alkyl disubstituted dianiline comprises 4,4′-methylene-bis-(3-chloro-2,6-diethylaniline), 4,4′-methylene-bis-(2,6-diethylaniline), 4,4′-methylene-bis-(2,6-diisopropylaniline), and/or 4,4′-methylene-bis-(2-methyl-6-isopropylaniline).
4 . The composition of claim 1 , wherein the ortho alkyl disubstituted dianiline is 4,4′-methylene-bis-(3-chloro-2,6-diethylaniline).
5 . The composition of claim 1 , wherein the polycarbonate polyol comprises poly(hexamethylene carbonate) diol.
6 . The composition of claim 1 , wherein the toluene diisocyanate comprises toluene-2,4-diisocyanate and toluene-2,6-diisocyanate.
7 . The composition of claim 1 , wherein a molar ratio of the polyurethane prepolymer to a curative is in a range of from 0.5:1 to 1.5:1.
8 . The composition of claim 1 , wherein the polyurethane prepolymer has a free NCO content (NCO %) of no greater than 8.5% NCO.
9 . The composition of claim 1 , wherein the polyol is poly (hexamethylene carbonate) diol, and
wherein the ortho alkyl disubstituted dianiline is 4,4′-methylene-bis-(3-chloro-2,6- diethylaniline).
10 . A process for preparing a polyurethane elastomer, the process comprising:
reacting the polyurethane prepolymer and curative of the curable polyurethane prepolymer composition of claim 1 to form a polyurethane elastomer.
11 . A polyurethane elastomer, prepared by the process of claim 10 .
12 . An article comprising:
the polyurethane elastomer of claim 11 .
13 . A curable polyurethane prepolymer composition, comprising:
a polyurethane prepolymer comprising, in polymerized form, a toluene diisocyanate and a polyol; and
an ortho alkyl disubstituted dianiline of formula (I)
R1 independently being a linear C 1 -C 6 alkyl, branched C 1 -C 6 alkyl, R2 being hydrogen or halogen, and A being —O—, —CH 2 —, —C(CH 3 ) 2 —, —SO 2 —, or —CO 2 (CH 2 )nO 2 C—, with n being 1, 2, 3, 4, 5 or 6,
wherein the polyol comprises polycarbonate polyol in a range of from 50 to 100 wt. %, based on total polyol weight,
wherein the polyurethane prepolymer comprises less than 0.1 wt. % of free TDI monomer, based on total polyurethane prepolymer weight, and
wherein the polycarbonate polyol comprises poly (hexamethylene carbonate) diol.
14 . The composition of claim 13 , wherein, in the ortho alkyl disubstituted dianiline of formula (I):
R1 is independently a linear Ci 1 -C 6 alkyl,
R2 is hydrogen or halogen, and
A is —CH 2 — or —C(CH 3 ) 2 —.
15 . The composition of claim 12 , wherein the ortho alkyl disubstituted dianiline comprises 4,4′-methylene-bis-(3-chloro-2,6-diethylaniline), 4,4′-methylene-bis-(2,6- diethylaniline), 4,4′methylene-bis-(2,6-diisopropylaniline), and/or 4,4′-methylene-bis-(2- methyl-6-isopropylaniline).
16 . The composition of claim 13 , wherein the ortho alkyl disubstituted dianiline is 4,4′-methylene-bis-(3-chloro-2,6-diethylaniline).
17 . The composition of claim 1 , wherein, in the ortho alkyl disubstituted dianiline of formula (I),
R1 is independently a branched C 1 -C 6 alkyl,
R2 is either hydrogen or halogen, and
A is —CH 2 — or —C(CH 3 ) 2 —.
18 . The composition of claim 13 , wherein, in the ortho alkyl disubstituted dianiline of formula (I),
R1 is independently a branched C 1 -C 6 alkyl,
R2 is either hydrogen or halogen, and
A is —CH 2 — or —C(CH 3 ) 2 —.
19 . The composition of claim 1 , wherein R2 is C1.
20 . A mud pump piston, header ring, seal, valve seat, power transmission belt, wheel, roller, bushing, or bearing, comprising:
the polyurethane elastomer of claim 11 .