Compact polyurethane

A process for producing a compact polyurethane having a density of ≥850 g/l, comprising the reaction of at least the components:

• i) a polyisocyanate composition;
• and
• ii) a polyol composition, comprising at least one polyether polyol (ii.1) which
• is obtained by reacting
• ii.1.1) a polyol starter with a functionality of 3 to 6
• with
• ii.1.2)propylene oxide and/or butylene oxide,
• in the presence of a boron-based, fluorine-containing Lewis acid catalyst (ii.1.3), wherein the polyether polyol (ii.1) has an equivalent molecular weight of 50 to 150 g/mol, and
• ii.1.4) optionally further auxiliaries and/or additives.

A method of using a compact polyurethane having a density of ≥850 g/l, obtained by reacting at least the components:

• i) a polyisocyanate composition;
• and
• ii) a polyol composition, comprising at least one polyether polyol (ii.1) which
• is obtained by reacting
• ii.1.1) a polyol starter with a functionality of 3 to 6
• with
• ii.1.2) propylene oxide and/or butylene oxide,
• in the presence of a boron-based, fluorine-containing Lewis acid catalyst (ii.1.3), wherein the polyether polyol (ii.1) has an equivalent molecular weight of 50 to 150 g/mol, and
• ii.1.4) optionally further auxiliaries and/or additives,
• the method comprising using the compact polyurethane for the production of a fiber composite.

A fiber composite material comprising the following components:

• a) a compact polyurethane having a density of ≥850 g/l, obtained by reacting at least the components:
• i) a polyisocyanate composition;
• and
• ii) a polyol composition, comprising at least one polyether polyol (ii.1)
• which is obtained by reacting
• ii.1.1) a polyol starter with a functionality of 3 to 6
• with
• ii.1.2) propylene oxide and/or butylene oxide,
• in the presence of a boron-based, fluorine-containing Lewis acid catalyst (ii.1.3),
• wherein the polyether polyol (ii.1) has an equivalent molecular weight of 50 to 150 g/mol, and
• ii.1.4) optionally further auxiliaries and/or additives;
• and
• b) fibers which are at least partially embedded in the compact polyurethane.

A process for producing a fiber composite, comprising:

• 1) providing fibers;
• 2) providing at least the components:
• i) a polyisocyanate composition;
• ii) a polyol composition, comprising at least one polyether polyol (ii.1) which is obtained by reacting
• ii.1.1) a polyol starter with a functionality of 3 to 6
• with
• ii.1.2) propylene oxide and/or butylene oxide,
• in the presence of a boron-based, fluorine-containing Lewis acid catalyst (ii.1.3);
• wherein the polyether polyol (ii.1) has an equivalent molecular weight of 50 to 150 g/mol, and
• ii.1.4) optionally further auxiliaries and/or additives;
• 3) mixing components i) and ii) of 2) to obtain a reactive mixture;
• 4) impregnating the fibers with the reactive mixture obtained as per 3);
• and
• 5) curing the reactive mixture to obtain a fiber composite, wherein the polyurethane is compact and has a density of ≥850 g/1.