ASSESSMENT OF 28-YEARS OLD CELLULOSE TRICAR BANILATE SAMPLES: MOLECULAR WEIGHT DISTRIBUTION AND VISCOMETRY MEASUREMENT
Twenty eight years old cellulose tricarbanilate samples (CTCs) prepared by Lauriol in 1983 (PhD thesis) from bleached cotton cellulose, submitted to various hydrolysis and oxidation treatments, were assessed for their molecular weight distribution and intrinsic viscosity using a Viscotek TDA 302 sizeexclusion chromatography instrument. All the samples had been preserved at ambient laboratory atmosphere and temperature in closed brown glass flasks. Since 1983, some flasks had been occasionally opened and closed. The comparison between old and new SEC-LALS measurements relies not only on the effect of polymer aging but also on the use of modern versus old chromatographic instruments and detectors. The main features of the results obtained were: (1) molecular weight remained constant after aging for high DP samples (untreated or mildly treated cellulose) and for low DP samples (severely treated cellulose); for some medium DP samples, slight depolymerisation was observed; and (2), a small decrease of polydispersity after aging was observed, but this also might be due to differences in the chromatographic systems used (effect of axial dispersion). The TDA instrument provided data for calculation of the Mark-HouwinkSakurada parameters of CTCs in THE Almost identical values for K and α (α=0.76) were found either by correlating
cellulose carbanilate aging molecular weight distribution viscometry Mark-Houwink-Sakurada parameters
G. Mortha C. Arnoldi
Universit(e) de Grenoble, INP-Pagora,Laboratoire de G(e)nie des Proc(e)d(e)s Papetiers, 461 rue de la Papeterie, BP 65, F-38402 Saint Martin dH(e)res Cedex, France
国际会议
16th International Symposium on Wood,Fiber and Pulping Chemistry(第十六届木材、纤维及制浆化学国际会议)
天津
英文
391-396
2011-06-08（万方平台首次上网日期，不代表论文的发表时间）