AN-g-casein浓溶液在毛细管流动中的末端校正

采用气压式毛细管流变仪，测定了实验室自制丙烯腈－酷素接枝共聚物（ＡＮ－ｇ－ｃａｓｅｉｎ）浓溶液的流变性能。实验结果发现：ＡＮ－ｇ－ｃａｓｅｉｎ浓溶液属切力变稀型非牛顿流体；在实验范围内，毛细管流动中的末端校正系数ｅ随切变速率的提高而增大，当切变速率较高时，ＡＮ－ｇ－ｃａｓｅｉｎ大分子在浓溶液中形成了束状物，拉伸变表受到了限制，ｅ值上升趋于极限；当切变速率较高，毛细管长径比较小时，真实剪切应力仅占表

End Correction in Capillary Flow of AN-g-casein Concentrated Solution

The rheological behaviour of AN g casein concentrated solution has been determined with a capillary rheometer. The results show that AN g casein concentrated solution is a kind of non Newtonian shear thinning fluid. The end correction factors at varied shear rate have been determined using capillaries of different length to radius ratio. The end correction factor increases with the increase of shear rate. The graft macromolecular sheaflike structure is formed and its stretching motion is limited as shear rate become higher, then the increase of value of end correction e tends towards the maximum. The real shear rate makes up only about 35 per cent of the total apparent shear rate when shear rate is higher and capillary ratio of length to radius is lower. It shows clearly that the end correction is necessary when rheology parameters are discussed.