Process for preparing urea urethane polymer

A process for preparing a urea urethane, the process comprising:

• i) introducing toluene diisocyanate into a reactor;
• ii) adding at least one monohydroxyl compound of formula (I)
• R—OH (I),
• wherein R is linear or branched alkyl comprising 4 to 22 carbon atoms, linear or branched alkenyl comprising 4 to 22 carbon atoms, cycloalkyl comprising 6 to 12 carbon atoms, aralkyl comprising 7 to 12 carbon atoms, a radical of formula CmH2m+1(O—CnH2n)x—, a radical of formula CmH2m+1[O—C(═O)—CvH2v]x—, or a radical of formula CmH2m+1(O—CnH2n)x−1[O—C(═O)—CvH2v]x—, wherein m is an integer from 1 to 22, n is an integer from 2 to 4, x is an integer from 1 to 15 and v is an integer from 4 to 6,
• to obtain at least one monoisocyanate adduct;
• whereby a molar ratio of the at least one monohydroxyl compound of formula (I) to the toluene diisocyanate is in a range of ≥1.05:1.0 to ≤1.2:1.0;
• iii) preparing a pre-mix by mixing at least one diamine, at least one polar aprotic solvent, and at least one lithium salt;
• and
• iv) feeding the pre-mix obtained in iii) into the reactor to react with the at least one monoisocyanate adduct obtained in ii), to obtain the urea urethane.