The chain arrangement within the crystalline lamellae has been the focus of polymer crystallizations. In this study, a series of protiated (H) and deuterated (D) poly (ɛ-caprolactone) (PCL) blends, block and random copolymers were investigated by small-angle neutron scattering (SANS) measurements. The spatial inhomogeneities of block copolymers were analyzed via Debye-Bueche method and temperature dependence of Flory-Huggins interaction parameter χ in the melt was extracted from fitting the scattering data to the random phase approximation model. Studying the changes of SANS signals further revealed that the copolymers exhibit cooling rate-dependent crystallization behaviors. A unique SANS double-peak pattern was found in D4/D10 50/50 blend and D10-D0-D10 triblock copolymers (where D0, D4, and D10 indicate PCL with different levels of deuteration), as a result of two types of contrasts: scattering length density (SLD) difference between lamellae of different components and density difference between amorphous and lamellar domains. These detailed findings complement our understanding of the complex crystallization processes of deuterated polyesters, which also suggest an avenue for fine control of crystal structures that adds to materials design.

结晶薄片内的链排列一直是聚合物结晶的焦点。在这项研究中，通过小角中子散射（SANS）测量研究了一系列多官能（H）和氘代（D）聚（ε-己内酯）（PCL）共混物，嵌段共聚物和无规共聚物。通过Debye-Bueche方法分析了嵌段共聚物的空间不均匀性以及Flory-Huggins相互作用参数χ的温度依赖性通过将散射数据拟合到随机相位近似模型中，可以提取熔体中的碳纳米管。研究SANS信号的变化进一步表明，该共聚物表现出依赖于冷却速率的结晶行为。在D4 / D10 50/50共混物和D10-D0-D10三嵌段共聚物（其中D0，D4和D10表示氘化程度不同的PCL）中发现了独特的SANS双峰图案：不同组分的薄片之间的散射长度密度（SLD）差异以及非晶和层状结构域之间的密度差异。这些详细的发现补充了我们对氘化聚酯复杂结晶过程的理解，这也为精细控制晶体结构提供了一条途径，从而增加了材料设计。