TY - BOOK AU - Bonfils F AU - Allet Don A AU - Koman Achi A AU - Laigneau J C AU - Sainte Beuve J AU - Sylla X TI - Steric exclusion chromatography study of natural rubber films prepared from fresh field latex PY - 1995/// PB - Journal of Natural Rubber Research KW - Hevea brasiliensis KW - Latex KW - Steric exclusion chromatography N2 - Cyclohexane was used to replace tetrahydrofuran (THF) as the elution phase in analysis of natural rubber by steric exclusion chromatography. The films, which were prepared from fresh field latex and dissolved in cyclohexane, had high gel rates up to 50;in some cases and overestimated average molecular weights. These problems were linked to certain hydrophilic non-rubber constituents and more particularly to the crosslinking they seem to bring about under certain conditions. This study showed that these crosslinking, which are not covalent, could be overcome by adding hydroxylamine neutral sulphate to the latex prior to film preparation, or by washing the films in deionised water before dissolving them. Using a mixed solvent, such as a cyclohexane and THF mixture (95/5,;v/v), to dissolve this type of samples also significantly limited the proportion of gel ER -