In this study, the self-assembly phenomenon of nucleator N, N′-dicyclohexylterephthalamide (DCHT) in isotactic polypropylene (iPP) has been investigated and reexamined from the viewpoint of sublimation and condensation. A correlation between the crystallization temperature (T_c) of iPP and the final heating temperature (T_f) was constructed, in which a “V” shape phenomenon and its dependence on DCHT concentration are presented. With the increase of DCHT concentration, both the onset and the bottom of the “V” shift to a higher T_f, which is ascribed to faster saturation of DCHT vapor or slower sublimation rate of DCHT at same T_f for the hybrids with high DCHT concentration. A phase diagram distinguishing various assembly structures of DCHT with different nucleation ability is proposed based on the DSC and optical results, in which four regions are included. Considering the strong hydrogen bonding between DCHT molecules, a simulated condensation mechanism for the particular needle-like and agglomerates were presented. Rheology results also provide indirect evidence to the phase transformation or condensation process, where two step condensation is observed and the lower temperature step could be attributed to the formation of agglomerates structure due to the “cage effect” of iPP supercooling melt to DCHT vapor.

在这项研究中，从升华和缩合的角度研究和重新审视了成核剂 N, N'-二环己基对苯二甲酰胺 (DCHT) 在等规聚丙烯 ( i PP) 中的自组装现象。结晶化温度（之间的相关性Ť _Ç的）我PP和最终的加热温度（Ť _˚F）构建，其中“V”形现象及其对DCHT浓度依赖性被呈现。随着 DCHT 浓度的增加，“V”的起点和底部都向更高的T _{f 移动}，这归因于 DCHT 蒸气饱和更快或 DCHT 在相同T _{f 下}升华速度更慢对于具有高 DCHT 浓度的杂种。基于DSC和光学结果，提出了区分具有不同成核能力的DCHT的各种组装结构的相图，其中包括四个区域。考虑到 DCHT 分子之间的强氢键，提出了特定针状和团聚体的模拟缩合机制。流变学结果也为相变或冷凝过程提供了间接证据，其中观察到两步冷凝，较低的温度步骤可归因于由于i PP 过冷熔体对 DCHT 蒸汽的“笼子效应”而形成的附聚物结构。