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Environmental fate & pathways

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According to a Mackay Level I model calculation, the main target compartments for Cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-, homopolymer, caprolactam-blocked will be sediment (50.1 %) and soil (49.5 %). The calculated Henry’s Law constant of <= 0.057 Pa m³/mol at 20 °C indicates very low volatility of Cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-, homopolymer, caprolactam-blocked from surface waters. With a log Koc of 6.1 l/kg, a „very high“ sorption potential of the substance to soil or sediment organic matter is expected (Blume scale). Very low release rates are expected in association with very high elimination via adsorption in waste water treatment plants.

 

The QSAR calculated rate constant for the OH sensitized photodegradation of Cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-, homopolymer, caprolactam-blocked (surrogate: blocked trimer) is approximately 112.1E-12 cm3/(molecule * s). At 500,000 OH radicals / cm3 (typical for central Europe), this corresponds to a half-life of 3.4 hours. Hydrolysis is very slow under environmental conditions (half-life > 1 year). While no ready biodegradation was observed in a manometric respirometry test, some adaptation and slow biodegradation are expected to occur in the environment. The partition coefficient 1-octanol/water was determined as log Kow = 8.6-9.6 at 23.3 °C and calculated as log Kow =15.22, indicating low potential for bioaccumulation due to low mobility.