Lehrstuhl für Chemische Technologie der Materialsynthese, Universität Würzburg, Würzburg, Germany.
Institut für Organische Chemie & Center for Nanosystems Chemistry (CNC), Universität Würzburg, Würzburg, Germany.
Biopolymers. 2019 Apr;110(4):e23259. doi: 10.1002/bip.23259. Epub 2019 Feb 7.
The self-assembly of block copolymers has captured the interest of scientists for many decades because it can induce ordered structures and help to imitate complex structures found in nature. In contrast to proteins, nature's most functional hierarchical structures, conventional polymers are disperse in their length distribution. Here, we synthesized hydrophilic and hydrophobic polypeptoids via solid-phase synthesis (uniform) and ring-opening polymerization (disperse). Differential scanning calorimetry measurements showed that the uniform hydrophobic peptoids converge to a maximum of the melting temperature at a much lower chain length than their disperse analogs, showing that not only the chain length but also the dispersity has a considerable impact on the thermal properties of those homopolymers. These homopolymers were then coupled to yield amphiphilic block copolypeptoids. SAXS and AFM measurements confirm that the dispersity plays a major role in microphase separation of these macromolecules, and it appears that uniform hydrophobic blocks form more ordered structures.
几十年来，嵌段共聚物的自组装一直吸引着科学家们的兴趣，因为它可以诱导有序结构，并有助于模拟自然界中发现的复杂结构。与自然界中最具功能性的层次结构——蛋白质不同，传统聚合物在长度分布上是分散的。在这里，我们通过固相合成（均一）和开环聚合（分散）合成了亲水性和疏水性多肽。差示扫描量热法测量表明，均匀的疏水性多肽在比其分散类似物短得多的链长下达到熔融温度的最大值，这表明不仅链长而且分散度对这些均聚物的热性能有相当大的影响。然后将这些均聚物偶联以得到两亲性嵌段共聚酯。小角 X 射线散射和原子力显微镜测量证实，分散度在这些大分子的微相分离中起着主要作用，似乎均匀的疏水性嵌段形成更有序的结构。
