Лако-красочные материалы — производство

Many polymers, especially polyethylene, are degraded by UV radiation under atmo­spheric conditions. Blacks can confer long-term stability to such polymers, firstly by absorbing the UV radiation and secondly by acting as free-radical acceptors to inactivate the active intermediate species formed in the degradation process. The stabilizing effect is improved with decreasing particle size and with increasing black concentration up to about 2-3%. Blacks with primary particle sizes of 20-25 nm are commonly used. The radical-accepting ability of blacks used as stabilizers can interfere with the free radical cross-linking of polymers [4.30].

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