The signifcance of sample preparation of historical and contemporary poly(vinyl chloride) objects to investigate the distribution and changes of molar mass by SEC-MALS-dRIRijavec, Tjaša (Avtor) Pawcenis, Dominika (Avtor) Kruczała, Krzysztof (Avtor) Strlič, Matija (Avtor) Kralj Cigić, Irena (Avtor) aggregatesassociationsize-exclusion chromatographygel-permeation chromatographyPVCheritage collectionheritage scienceThe distribution of molar mass of historical and contemporary poly(vinyl chloride) objects was determined using size exclusion chromatography with multi-angle light scattering detection. The weight average molar mass was determined for a collection of 57 samples, ranging from 75 to 186 kg/mol with a median of 102 kg/mol. Rigid PVC objects were found to have a signifcantly lower weight average molar mass ($M_w$ =81 kg/mol) than plasticized ones ($M_w$ =102 kg/mol). Thin objects also exhibited signifcantly lower $M_w$ than bulky objects. A substantial presence of aggregates was noted and characterized as an‘aggregate ratio’ for the entire collection. Heating a solution of poly(vinyl chloride) in THF at 55 °C for 5 h proved successful in the dissociation of the aggregates and allowed for an accurate determination of molar mass. The uncertainty of the $M_w$ determination was statistically evaluated and used to study the efects of accelerated degradation on $M_w$. No statistically signifcant changes in Mw were observed in samples artifcially aged at 50 °C to 80 °C for up to 15 weeks, indicating that $M_w$ does not decrease during degradation of a PVC heritage object and that accelerated degradation does not lead to polymer crosslinking.20232023-08-02 10:14:49Članek v reviji148211UDK: 543.54:678.743.2:7.025ISSN pri članku: 2050-7445DOI: 10.1186/s40494-023-01003-5COBISS_ID: 160389891sl