STUDY ON THE KINETICS OF LIGNIN METHYLOLATION

被引:16
作者
PENG, W [1 ]
RIEDL, B [1 ]
BARRY, AO [1 ]
机构
[1] UNIV LAVAL, FAC FORESTERIE & GEOMAT, DEPT SCI BOIS, CTR RECH SCI & INGN MACROMOLEC, Ste Foy G1K 7P4, PQ, CANADA
关键词
D O I
10.1002/app.1993.070481009
中图分类号
O63 [高分子化学(高聚物)];
学科分类号
070305 ; 080501 ; 081704 ;
摘要
The kinetics of lignin (ammonium-based lignosulfonate and sodium-based lignosulfonate) methylolation were studied in solution by monitoring the rate of disappearance of formaldehyde and by using differential scanning calorimetry (DSC) techniques under an isothermal program, at 20, 40, 50, and 60-degrees-C, respectively. The kinetic parameters obtained from these two methods agree with each other. The results show that the degree of lignin methylolation depends on the number and availability of reactive sites per C-9 unit of lignin. Lignin methylolation has a lower activation energy and a lower preexponential factor than that of phenol methylolation. Lignins took a shorter time to reach complete methylolation than did phenol at the low temperatures used here.
引用
收藏
页码:1757 / 1763
页数:7
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