�꾮Һ��ѡ����˳�����м��ؿ�ѧ��̽���̵Ĺؼ�����֮һ��ΪѰ��һ�����Ͱ�ȫ���������͵����꾮Һ�������������һԪ֬���������Ԫ֬���������ӽṹ�ص㣬�����ֲ�ͬ��������͵������ܽ����������о������������ֻ�����������ܶ����¶ȵı仯�����鷢�֣����¶��½�ʱ����������ȶ�����һ�����¶ȣ����¶ȵĸߵ������ķ��ӽṹ�������������Ӽ���������Ӱ�졣���������ɡ����ӽṹ�����Ӽ���������С��Ӱ���ܶ����¶ȵı仯��ϵ�������ܶȵĴ�С���ܶ����ӵ��ٶ�Ӱ��ϴ�

One of the key techniques of successfully completing the polar scientific drilling is to find a kind of available drilling fluid�� In order to find a new type of drilling fluid with low temperature resistance for safety and en- vironmental protection��the authors analyzed the structural characteristics of the monobasic fatty acid ester with a di- basic fatty acid ester molecule��and studied the capability of three mixed ester in low-temperature�� The changes of viscosity and density with temperature of the three kinds of mixed ester were tested�� The results showed that when the temperature dropped��the viscosity of the mixed ester had a thickening temperature��and the level of thickening temperature was effected by the ester molecular structure��molecular weight and intermolecular force�� The composi- tion of mixed ester��molecular structure and the intermolecular force were not affectted the changes of density with temperature��but the impact for the size and the increasing speed of density were bigger��