Stabilizers for urea urethanes

A process for obtaining a urea urethane, encompassing or consisting of the following steps:

• (a) providing a monohydroxyl compound of formula (I)
• R—OH (I)
• in which R is n-alkyl or isoalkyl containing 4 to 22 carbon atoms, cycloalkyl containing 6 to 12 carbon atoms, aralkyl containing 7 to 12 carbon atoms or a radical of the formula CmH2m+1(O—CnH2n)x— or CmH2m+1(OOC—CvH2v)x—, and m stands for an integer of from 1 to 22, n stands for an integer of 2 to 4, x for an integer of 1 to 15 and v means 4 or 5;
• (b) providing a diisocyanate compound of formula (II)
• OCN-[A]-NCO (II)
• in which A stands for a linear or branched alkylene radical having 2 to 10 carbon atoms or a toluene radical;
• (c) reacting said monohydroxyl compound and said diisocyanate compound to form a pre-polymer;
• (d) reacting said pre-polymer with a diamine compound, said diamine compound being selected from the group consisting of
• (d1) compound (III)
• H2N—[B]—NH2 (III)
• where B stands for a linear or branched alkylene group having 2 to 12 carbon atoms;
• and/or
• (d2) compound (IV)
• and/or
• (d3) compound (V)
• in which R′″ stands for hydrogen or a methyl group,
• wherein the formation of the urea urethane takes place in the presence of at least one stabilizer according to formula (VI)
• wherein R1, R2, R3, R4 and R5 independently from each other represent hydrogen, a linear or branched, saturated or unsaturated aliphatic, cycloaliphatic or aromatic hydrocarbon group having 1 to 12 carbon atoms, or
• wherein R1 and R2 and/or R3 and R4 and/or R5 form parts of an aromatic or heteroaromatic ring system having 5 to 12 carbon atoms and being optionally substituted.