Rigid PUR/PIR foams of isopropylidenediphenol-based polyethers

1. An ethoxylated Bisphenol A (BPA) resin, comprising

a) at least 10% by weight, based on 100% by weight of said ethoxylated BPA resin, of an ethoxylate of 4,4′-isopropylidenediphenol,

b) at least 5% by weight, based on 100% by weight of said ethoxylated BPA resin, of an ethoxylate of 2,4′- and 2,2′-isopropylidenediphenol, and

c) at least 10% w/w by weight, based on 100% by weight of said ethoxylated BPA resin, of an ethoxylate of components containing the structural elements which are derived from phenol, acetone and/or isopropylidenediphenol, but which are not isomers of the isopropylidenediphenol.

2. The ethoxylated Bisphenol A (BPA) resin according to claim 1 with a hydroxyl value of 100 to 400 mg KOH/g, and a viscosity measured at 25° C. of 600 to 10000 mPas.

3. A method for producing an ethoxylated Bisphenol A (BPA) resin according to claim 1 , comprising reacting a BPA resin comprising at least 10% by weight, based on 100% by weight of said BPA resin, of 4,4′-Isopropylidendiphenol, at least 5% by weight, based on 100% by weight of said BPA resin, of the 2,4′- and 2,2′-isomers of the bisphenol base body and at least 10% by weight, based on 100% by weight of said BPA resin, of compounds with chromane and/or indane base bodies with an ethylene oxide-containing alkylene oxide mixture comprising at least 50% by weight, based on 100% by weight of said ethylene oxide-containing alkylene oxide mixture, of ethylene oxide.

4. The method according to claim 3 , wherein the reaction is carried out in the homogeneous phase.

5. The method according to claim 3 , wherein at least 1.5 mols of an ethylene oxide-containing alkylene oxide mixture are used per mol of phenolic hydroxyl group in the BPA resin in the reaction.

6. The method according to claim 4 , wherein the reaction occurs in the presence of a tertiary amine catalyst having with aliphatic, cycloaliphatic, aromatic and/or araliphatic residues bound to the nitrogen atom, and/or an aromatic amine catalyst.

7. The method according to claim 6 , wherein the amine is neutralised after the reaction of the BPA resin with the ethylene oxide-containing alkylene oxide mixture.

8. The method according to claim 3 , wherein no solvent is present during the reaction.

9. An ethoxylated Bisphenol A (BPA) resin, obtainable by the method according to claim 3 .

10. A method for producing a PUR/PIR-rigid foam, comprising reacting

a) a polyol component

c) at least one propellant,

d) at least one catalyst,

e) if necessary, at least one flame retardant and/or further auxiliary substances and additives, and

f) if necessary, at least one further compound with at least two groups reactive with respect to isocyanates,

with a polyisocyanate b), wherein the polyol component a) comprises an ethoxylated Bisphenol A (BPA) resin according to claim 1 .

11. A method according to claim 10 , comprising reacting

a) 19 to 29% by weight, based on 100)% by weight of components a), b, c) d), e) and f), of a BPA resin ethoxylate according to claim 1 ,

c) 0.7 to 15% by weight, based on 100% by weight of components a), b), c), d), e) and f) of a at least one propellant,

d) 0.06 to 3% by weight, based on 100% by weight of components a), b), c), d), e) and f), of at least one catalyst,

e) 0.5 to 5% by weight, based on 100% by weight of components a), b), c), d), e) and f), of a flame retardant and/or further auxiliary substances and additives,

f) 0-10% by weight, based on 100% by weight of components a), b), c), d), e) and f) of further compounds with at least two groups reactive with respect to isocyanates, with

b) 56 to 74% by weight, based on 100% by weight of components a), b), c), d), e) and f), of a at least one polyisocyanate.

12. A method according to claim 10 , wherein said polyisocyanate b) comprises at least one of toluylene diisocyanate (tdi), diphenylmethane diisocyanate (mdi), polyphenylene polymethylene polyisocyanates (polymeric mdi), or combinations thereof, and said propellant c) comprises at least one of water, cyclopentane, n-pentane, iso-pentane, fluorocarbons with 3 or 4 carbon atoms, partly-halogenated alkenes with 3 or 4 carbon atoms, or combinations thereof.

13. A method according to claim 10 , wherein the foaming is carried out against at least one surface layer while forming a compound element comprising the PUR/PIR rigid foam and at least one surface layer.

14. A method according to claim 13 , wherein at least one surface layer consists of a material comprising paper, cardboard, concrete, wood, particle board, aluminium, copper, steel, stainless steel, plastic, or combinations thereof.

15. The PUR/PIR rigid foam obtained according to the method of claim 10 .