动态膜渗透压法测定生漆多糖水溶液

<正> 生漆是一种性能优异的超耐久涂料,其主要成份为漆酚、漆酶、糖蛋白、多糖和水。多糖由D-半乳糖(65％),4-O-甲基-D-葡萄糖醛酸(24％),D-葡萄糖醛酸(3％),L-阿拉伯糖(4％)和鼠李糖(3％)组成。它带大量支链,在侧链上有大约1/4mol羧基从而显示聚电解质溶液性质。

DYNAMIC MEMBRANE OSMOMETRY OF LACQUER POLYSACCHARIDE IN AQUEOUS SOLUTION

The number average molecular weight Mn, second virial coefficient A2 and intrinsic viscosity [η] were measured for unfractionated and fractionated samples of a lacquer polysaccharide from Vietnam by dynamic membrane osmometry and vlscosimetry. The aqueous 0.5MKCl/10% cadoxen was chosen as a solvent, which not only rapidly dissolved the polysaccharide to form a particularly stable solution, but also did not destroy the regenerated cellulose membrane used for osmometry. The Mark-Houwink equation and A2~ Mn relationship for the polysaccharide in aqueous 0.5M KCl/10% cadoxen at 30℃ were found respectively to be =1.44×10-2 Mn0.55 and A2= 0.142Mn -0.48. This implies that branched polysaccharide in the aqueous solution takes a fairly compact coil conformation.