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Abstract：
Due to their diverse and unique physical properties, miktoarm star copolymers (μ-SCPs) have garnered significant attention. In our study, we employed α-monobomoisobutyryl-terminated polydimethylsiloxane (PDMS-Br) to carry out styrenics-assisted atom transfer radical coupling (SA ATRC) in the presence of 4-vinylbenzyl alcohol (VBA) at 0 °C. By achieving high coupling efficiency (χc = 0.95), we obtained mid-chain functionalized PDMS-VBAm-PDMS polymers with benzylic alcohols. Interestingly, matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) analysis revealed the insertion of only two VBA coupling agents (m = 2). Subsequently, the PDMS-VBA2-PDMS products underwent mid-chain extensions using ε-caprolactone (ε-CL) through ring-opening polymerization (ROP) with an efficient organo-catalyst at 40 °C, resulting in the synthesis of novel (PDMS)2-μ-(PCL)2 μ-SCPs. Eventually, novel (PDMS)2-μ-(PCL)2 μ-SCPs were obtained. The obtained PDMS-μ-PCL μ-SCPs were further subjected to examination of their solid-state self-assembly through small-angle X-ray scattering (SAXS) experiments. Notably, various nanostructures, including lamellae and hexagonally packed cylinders, were observed with a periodic size of approximately 15 nm. As a result, we successfully developed a simple and effective reaction combination (Є) strategy (i.e., SA ATRC-Є-ROP) for the synthesis of well-defined PDMS-μ-PCL μ-SCPs. This approach may open up new possibilities for fabricating nanostructures from siloxane-based materials.
摘要：
由于其多样化和独特的物理性质，miktoarm星形共聚物（μ-SCP）引起了极大的关注。在我们的研究中,我们使用α-单溴异丁酰基封端的聚二甲基硅氧烷（PDMS-Br）在0°C下在4-乙烯基苄醇（VBA）的存在下进行苯乙烯辅助的原子转移自由基偶联（SAATRC）。通过实现高耦合效率(χc=0.95)，我们用苄醇获得了中链官能化的PDMS-VBAm-PDMS聚合物。有趣的是,基质辅助激光解吸/电离飞行时间质谱（MALDI-TOFMS）分析显示仅插入了两种VBA偶联剂（m=2）。随后，PDMS-VBA2-PDMS产品使用ε-己内酯（ε-CL）通过开环聚合（ROP）在40°C下用有效的有机催化剂进行中链延伸，导致合成新型(PDMS)2-μ-(PCL)2μ-SCP。最终,获得了新型（PDMS）2-μ-（PCL）2μ-SCP。通过小角度X射线散射（SAXS）实验，进一步对获得的PDMS-μ-PCLμ-SCP进行固态自组装检查。值得注意的是,各种纳米结构，包括薄片和六角形包装的圆柱体，观察到具有约15nm的周期性尺寸。因此,我们成功开发了一种简单有效的反应组合()策略(即，SAATRC--ROP）用于合成定义明确的PDMS-μ-PCLμ-SCP。这种方法可以为从硅氧烷基材料制造纳米结构开辟新的可能性。
