The structure of copolymer crystals formed from dilute solution and in bulk
The structure of copolymer crystals formed from dilute solution and in bulk
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DOI：
10.1002/pol.1984.180221003
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发表时间：
1984-10
期刊：
影响因子：
--
通讯作者：
R. Domszy;R. Alamo;P. Mathieu;L. Mandelkern
中科院分区：
文献类型：
--
作者：
R. Domszy;R. Alamo;P. Mathieu;L. Mandelkern
研究了一系列氢化聚丁二烯在本体和稀溶液中结晶的热力学和结构性质。这些聚合物是乙基支化乙烯共聚物，具有窄的相对分子质量和组成分布。尽管对于这两种结晶模式，这些无规序列共聚物都表现出层状结晶习性，但所有独立的物理化学测量结果在数量上是一致的，表明相对较薄的微晶具有较大的无定形无序覆盖层。这被认为是共聚物结晶的一个非常普遍的现象。由拉曼-拉曼光谱和小角X射线散射测定的堆芯厚度很好地吻合。从密度、熔化热、拉曼内模、拉曼林和小角x射线散射获得了结晶度的定量一致的值。值得注意的是，独立的热力学方法和结构方法给出了相同的结果。
The thermodynamic and structural properties of a series of hydrogenated polybutadienes, crystalized in the bulk and from dilute solution, have been investigated. These polymers are ethyl-branched ethylene copolymers with narrow molecular weight and composition distributions. Despite the fact that for both modes of crystallization these random-sequence copolymers display a lamellar crystalline habit, all of the independent physical chemical measurements are quantitatively consistent in indicating a relatively thin crystallite with a large amorphous disordered overlayer. This is seen to be a very general phenomenon for copolymer crystallization. The core thicknesses, determined from Raman LAM and from small-angle x-ray scattering, are in good agreement. Quantitatively consistent values of the degree of crystallinity are obtained from the density, enthalpy of fusion, Raman internal modes, Raman LAM, and small-angle x-ray scattering. It is significant that independent thermodynamic and structural methods give the same result.