A scattering function for correlated lamellae
A scattering function for correlated lamellae
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相关片层的散射函数
DOI：
10.1016/j.polymer.2021.124281
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发表时间：
2021
期刊：
影响因子：
4.6
通讯作者：
Sukumaran Sathish K.
中科院分区：
文献类型：
--
作者：
Camara Michael;Rishi Kabir;Beaucage Gregory;Sukumaran Sathish K.
熔融结晶的聚合物显示出由堆叠的层状单晶组成的涌现的、多层次的、有序的结构，所述层状单晶形成纤维状或其它介观结构，所述纤维状或其它介观结构进而形成宏观微晶。这些复杂组件的小角度散射的一个主要特征是与堆叠周期相关的相关峰。提出了一种新的基于模型的功能，从这种相关的层状多层次结构的小角散射数据。通常，散射数据的常规使用仅限于一维分析，以根据洛伦兹校正数据（I（q）q2 versusq）确定长周期。有时使用数据的傅立叶变换来确定电子密度分布的1-D成对相关函数，该函数已根据这些材料的结构进行了进一步分析。Hermans（1944; Hosemann，1950）[1，2]在20世纪40年代引入了一个简单的1-D拟合模型，该模型仅限于无限宽的2-D片，并取得了一定的成功。提出了一种新的方法，统一Born-Green函数（UBG），使用的统一功能，适用于相关的层状结构，并结合了Born-Green描述的一维相关性。UBG拟合允许量化的平均片层纵横比，堆叠内的局部结晶度，量化的堆叠与非堆叠无定形，和两种类型的无序除了堆叠周期和片层厚度。UBG可以解释更高水平的结构，例如嵌段共聚物中的结晶域和卷曲的层状结构。将UBG拟合与Hermans（1944; Hosemann，1950）[1，2]和混合Hermans函数进行比较。显示了与各种聚乙烯数据集的拟合，范围从等温结晶的分子量标准样品到从熔体中淬火的商业HDPE和茂金属吹膜样品。从文献中的其他几个例子进行了探讨。结果表明，统一的适合允许新的理解的影响的热和机械的历史，链结构，填料，成核剂，和添加剂的晶体结构和由此产生的物理性能。UBG方法的局限性。
Melt crystallized polymers display an emergent, multi-hierarchical, ordered structure made up of stacked lamellar single crystals that form fibrous or other meso structures which, in turn, form macroscopic crystallites. A dominant feature of small-angle scattering from these complex assemblies is a correlation peak associated with the stacking period. A new model-based function is proposed for small-angle scattering data from such correlated lamellar multi-hierarchical structures. Generally, routine use of scattering data has been limited to a 1-d analysis to determine the long period from Lorentz corrected data (I(q)q2versusq). Fourier transforms of the data are sometimes used to determine the 1-d pairwise correlation function for the electron-density distribution which has been further analyzed in terms of the structure of these materials. A simple 1-d fitting model limited to infinite width 2-d sheets was introduced by Hermans (1944; Hosemann, 1950) [1,2] in the 1940s with some success. A new approach, the Unified Born-Green Function (UBG), is proposed that uses the Unified Function as adapted to correlated lamellar structures and incorporates a Born-Green description of one-dimensional correlations. The UBG fit allows quantification of the average lamellar aspect ratio, the local degree of crystallinity within a stack, quantification of the stacking versus non-stacking amorphous, and two types of disorder in addition to the stacking period and lamellar thickness. UBG can account for higher levels of structure such as crystalline domains in block copolymers and convoluted lamellar structure. The UBG fit is compared to the Hermans (1944; Hosemann, 1950) [1,2] and a hybrid-Hermans function. Fits to data sets from a wide range of polyethylene are shown ranging from molecular weight standard samples that are isothermally crystallized, to commercial HDPE quenched from the melt and a metallocene blown film sample. Several other examples from the literature are explored. It is shown that the Unified fit allows for new understanding of the impact of thermal and mechanical history, chain structure, fillers, nucleating agents, and additives on the crystalline structure and the resulting physical properties. Limitations of the UBG approach are noted.
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影响因子：
3.4
作者：
Burger, Christian;Zhou, Hong-wen;Glimcher, Melvin J.
通讯作者：
Glimcher, Melvin J.
半结晶聚合物：SAXS 的层状形态
DOI：
10.1016/b0-08-043152-6/01807-6
发表时间：
2002
期刊：
--
影响因子：
--
作者：
B. Hsiao
通讯作者：
B. Hsiao
非线性聚乙烯的 X 射线衍射研究 I. 室温观察。
DOI：
10.1002/pol.1985.180231210
发表时间：
1985
期刊：
Journal of Polymer Science Part B
影响因子：
--
作者：
C. G. Vonk;A. Pijpers
通讯作者：
A. Pijpers
自组装取向层状纳米复合薄膜的 SAXS：一种先进的评估方法
影响因子：
6.1
作者：
W. Ruland;B. Smarsly
通讯作者：
B. Smarsly
聚乙烯的小角 X 射线散射：扭曲的层状结构
影响因子：
3
作者：
C. Marega;A. Marigo;V. Causin
通讯作者：
V. Causin