Damage function for poly(vinyl chloride) in heritage collections

Yellowing of plastic objects as a consequence chemical degradation is common heritage conservation challenge. In the case poly(vinyl chloride) elimination hydrogen chloride leads to formation polyene sequences that act chromophores. The objective this work was quantitatively evaluate rate observed yellowing, relevant room conditions during long-term storage collections. Degradation quantified increase in b* colour coordinate accelerated at 50 and 70 °C function temperature, relative humidity, plasticizer content, polymer molecular weight. significance each variable investigated with multiple linear regression. Lower lower higher weight content were associated rates. activation energy 86 kJ/mol calculated. concept ‘1- °C-equivalent’ introduced enable prioritisation from management aspect. resulting model can be used shape environmental guidelines identify most vulnerable