Immiscible polyurethane pultrusion formulations and processes

1 . A reaction system for the preparation of a fiber reinforced composite according to the pultrusion process comprising:

continuous fiber reinforcing material; and

an immiscible polyurethane formulation comprising

a polyisocyanate component containing at least one polyisocyanate, and

an isocyanate-reactive component containing at least one isocyanate-reactive compound.

2 . The reaction system according to claim 1 , wherein the fiber reinforcing material is selected from the group consisting of single strands, braided strands, woven mat structures, non-woven mat structures and combinations thereof.

3 . The reaction system according to claim 1 , wherein the fiber reinforcing material comprises one or more of glass fibers, glass mats, carbon fibers, polyester fibers, natural fibers, aramid fibers, basalt fibers and nylon fibers.

4 . The reaction system according to claim 1 , wherein the fiber reinforcing material comprises glass fibers.

5 . The reaction system according to claim 1 , wherein the at least one polyisocyanate is selected from the group consisting of ethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,12-dodecane diisocyanate, cyclobutane-1,3-diisocyanate, cyclohexane-1,3-and -1,4-diisocyanate, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclohexane (“isophorone diisocyanate”), 2,4- and 2,6-hexahydrotoluene diisocyanate, dicyclohexylmethane-4,4′-diisocyanate (“hydrogenated MDI”, or “HMDI”), 1,3- and 1,4-phenylene diisocyanate, 2,4- and 2,6-toluene diisocyanate (“TDI”), diphenylmethane-2,4′- and/or -4,4′-diisocyanate (“MDI”), naphthylene-1,5-diisocyanate, triphenyl-methane-4,4′,4″-triisocyanate, polyphenyl-polymethylene-polyisocyanates (“crude MDI”), norbornane diisocyanates, m- and p-isocyanatophenyl sulfonylisocyanates, perchlorinated aryl polyisocyanates, carbodiimide-modified polyisocyanates, urethane-modified polyisocyanates, allophanate-modified polyisocyanates, isocyanurate-modified polyisocyanates, urea-modified polyisocyanates, biuret-containing polyisocyanates, isocyanate-terminated prepolymers and mixtures thereof.

6 . The reaction system according to claim 1 , wherein the at least one isocyanate-reactive compound is selected from the group consisting of softblock polyols, rigid polyols, chain extenders, crosslinkers and combinations thereof.

7 . A pultrusion process for preparing a fiber reinforced polyurethane composite, the process comprising:

continuously pulling a roving or tow of continuous fiber reinforcing material successively through an impregnation chamber and a die;

continuously feeding an immiscible polyurethane formulation comprising a polyisocyanate component containing at least one polyisocyanate and an isocyanate-reactive component containing at least one isocyanate-reactive compound to the impregnation chamber;

contacting the fiber reinforcing material with the formulation in the impregnation chamber such that substantially complete wetting of the material by the formulation occurs;

directing the fiber reinforcing material through a die heated to reaction temperature to form a solid composite; and

drawing the composite from the die,

wherein conditions in the impregnation chamber are such that substantially no polymerization takes place.

8 . The pultrusion process according to claim 7 , wherein the fiber reinforcing material is selected from the group consisting of single strands, braided strands, woven mat structures, non-woven mat structures and combinations thereof.

9 . The pultrusion process according to claim 7 , wherein the fiber reinforcing material comprises one or more of glass fibers, glass mats, carbon fibers, polyester fibers, natural fibers, aramid fibers, basalt fibers and nylon fibers.

10 . The pultrusion process according to claim 7 , wherein the fiber reinforcing material comprises glass fibers.

11 . The pultrusion process according to claim 7 , wherein the at least one polyisocyanate is chosen from ethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,12-dodecane diisocyanate, cyclobutane-1,3-diisocyanate, cyclohexane-1,3-and -1,4-diisocyanate, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclohexane (“isophorone diisocyanate”), 2,4- and 2,6-hexahydrotoluene diisocyanate, dicyclohexylmethane-4,4′-diisocyanate (“hydrogenated MDI”, or “HMDI”), 1,3- and 1,4-phenylene diisocyanate, 2,4- and 2,6-toluene diisocyanate (“TDI”), diphenylmethane-2,4′- and/or -4,4′-diisocyanate (“MDI”), naphthylene-1,5-diisocyanate, triphenyl-methane-4,4′,4″-triisocyanate, polyphenyl-polymethylene-polyisocyanates (“crude MDI”), norbornane diisocyanates, m- and p-isocyanatophenyl sulfonylisocyanates, perchlorinated aryl polyisocyanates, carbodiimide-modified polyisocyanates, urethane-modified polyisocyanates, allophanate-modified polyisocyanates, isocyanurate-modified polyisocyanates, urea-modified polyisocyanates, biuret-containing polyisocyanates, isocyanate-terminated prepolymers and mixtures thereof.

12 . The pultrusion process according to claim 7 , wherein the at least one isocyanate-reactive compound is selected from the group consisting of softblock polyols, rigid polyols, chain extenders, crosslinkers and combinations thereof.

13 . The fiber reinforced polyurethane composite made by the process according to claim 7 .

14 . In a process for preparing a fiber reinforced polyurethane composite by pultrusion, the improvement comprising including a phase separated polyurethane formulation.

15 . The process according to claim 14 , wherein the phase separated polyurethane formulation comprises a polyisocyanate component containing at least one polyisocyanate and an isocyanate-reactive component containing at least one isocyanate-reactive compound.

16 . The process according to claim 14 , wherein the fiber reinforcing material is selected from the group consisting of single strands, braided strands, woven mat structures, non-woven mat structures and combinations thereof.

17 . The process according to claim 14 , wherein the fiber reinforcing material comprises one or more of glass fibers, glass mats, carbon fibers, polyester fibers, natural fibers, aramid fibers, basalt fibers and nylon fibers.

18 . The process according to claim 14 , wherein the fiber reinforcing material comprises glass fibers.

19 . The process according to claim 14 , wherein the at least one polyisocyanate is selected from the group consisting of ethylene diisocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,12-dodecane diisocyanate, cyclobutane-1,3-diisocyanate, cyclohexane-1,3-and -1,4-diisocyanate, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclohexane (“isophorone diisocyanate”), 2,4- and 2,6-hexahydrotoluene diisocyanate, dicyclohexylmethane-4,4′-diisocyanate (“hydrogenated MDI”, or “HMDI”), 1,3- and 1,4-phenylene diisocyanate, 2,4- and 2,6-toluene diisocyanate (“TDI”), diphenylmethane-2,4′- and/or -4,4′-diisocyanate (“MDI”), naphthylene-1,5-diisocyanate, triphenyl-methane-4,4′,4″-triisocyanate, polyphenyl-polymethylene-polyisocyanates (“crude MDI”), norbornane diisocyanates, m- and p-isocyanatophenyl sulfonylisocyanates, perchlorinated aryl polyisocyanates, carbodiimide-modified polyisocyanates, urethane-modified polyisocyanates, allophanate-modified polyisocyanates, isocyanurate-modified polyisocyanates, urea-modified polyisocyanates, biuret-containing polyisocyanates, isocyanate-terminated prepolymers and mixtures thereof.

20 . The process according to claim 14 , wherein the at least one isocyanate-reactive compound is selected from the group consisting of softblock polyols, rigid polyols, chain extenders, crosslinkers and combinations thereof.