CHARACTERIZATION OF PHOTOCHEMICALLY DEGRADED NEWSPRINT SOLUBLES .2. FURTHER NMR-STUDIES

Newsprint was exposed to direct or indirect sunlight for periods ranging from 5 days to 15 months and then extracted with 85% acetone-water. The yield and composition of the acetone-water soluble degradation products was determined, the latter using I3C NMR spectroscopy. The major monomeric product was vanillin initially, but vanillic acid rapidly became and stayed the major lignin fragment. The aliphatic acid content increased throughout. Carbohydrate fragments became a significant component äs the yield increased. At comparable yield, direct sunlight products had a slightly different composition from indirect sunlight products. Pre-extraction of the newsprint had little effect on the degradation process. © 1990 Walter de Gruyter