URETHANGRUPPEN AUFWEISENDE DIISOCYANATE, EIN VERFAHREN ZU IHRER HERSTELLUNG UND IHRE VERWENDUNG ALS BINDEMITTEL BZW. BINDEMITTELKOMPONENTE IN POLYURETHANLACKEN.

摘要

Di-isocyanates of formula R1-(-O(R2O-)n-CONH-R3-NCO)2 (I) are new. R1 = -CH(CMe3)-C(Me)2-CH2-; R2 = -CH2CH2-, -CH2CH(CH3)-, or -CO(CH2)5-; R3 = difunctional hydrocarbon residue, opt. contg. ester gps., joining NCO gps. of an organic di-isocyanate of mol. wt. 132-336; n = 0, 1, or 2. Opt. (I) are mixt. with up to 90 wt.% on wt. mixt., urethane gp.- contg. polyisocyanate (II) of formula R4-(O-CONH-R3-NCO)m and opt. iwth minor amts. of oligomeric polyisocyanates (III) contg. urethane gps., where R4 = m-valent aliphatic 2-10C hydrocarbon gp. different from R, opt. contg. ether gps., and m = 2 or 3. Prepn. of (I) is effected by urethane formation between di-isocyanate of formula R3(NCO)2 and alcohol of formula R1 O-(R2O)nH 2 or mixt. with alcohol of formula R4(OH)m at NCO/OH equiv. ratio 1.7-15:1 then opt. removing any remaining R3(NCO)2 to max. 2% on (I).