传统的高斯链自洽场理论不适用于聚合物链高度强伸展的体系。为了弥补这一缺陷，发展了一种基于聚合物珠链模型的自洽场理论方法，其中聚合物链上的珠子通过非线性Warner弹簧势（Warner spring potential）连接。通过赝谱方法求解自洽场方程，并将该方法应用于两嵌段共聚物的微相行为研究，验证了方法的有效性。研究中，构建了层状结构周期与 Flo ry‐H ug‐gins参数、非键势作用范围及聚合度的标度关系，发现所得的标度关系与强分离理论预测的结果吻合。此外，研究了极限键长对微相行为的影响，研究表明通过改变极限键长可以将自由结合链模型和高斯链模型关联起来。该方法可应用于传统高斯链自洽场理论不适合的体系，如低盐浓度下的强聚电解质体系等。%Conventional self‐consistent field theory (SCFT ) ,based on Gaussian chains ,cannot be applied to polymer systems with highly extended chains .To overcome this drawback ,we developed a SCFT method based on discrete polymer chains involving a finite number of beads that are connected by a Warner spring potential .The SCFT of Warner spring chains numerically performed using a pseudospectral algorithm ,was found to be equally efficient to that of Gaussian chains .To test the effectiveness ,this de‐veloped SCFT was employed to study the phase behavior of diblock copolymers .The scaling of lamellar period was constructed with respect to the Flory‐Huggins parameter ,finite range of nonbonded interactions ,and degree of polymerization .The scaling law agrees well with the prediction by strong‐stretching theory .In addition ,the effect of the maximum extension of a bond on the phase behavior was examined .It was found that the SCFT of Warner spring chains can bridge the gap between those of freely jointed chains and discrete Gaussian chains ,depending on the maximum extension of a bond .The present model could be applied to many special systems such as polyelectrolytes under low salt conditions for which the standard SCFT is not suited .
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