Degradable cellulose‐based polymer brushes with controlled grafting densities
Degradable cellulose‐based polymer brushes with controlled grafting densities
复制标题
DOI：
10.1002/pola.29481
复制
发表时间：
2019-12
期刊：
影响因子：
--
通讯作者：
Mateusz Olszewski;Lingchun Li;Guojun Xie;A. Keith;S. Sheiko;K. Matyjaszewski
中科院分区：
文献类型：
--
作者：
Mateusz Olszewski;Lingchun Li;Guojun Xie;A. Keith;S. Sheiko;K. Matyjaszewski
通过 ATRP 从纤维素衍生的主链上接枝聚丙烯酸正丁酯 (PBA) 侧链，合成了具有可变接枝密度和低分散性的纤维素基聚合物刷。市售醋酸纤维素与 2-溴异丁酰溴 (2-BiBB) 在 NMP 中的酯化反应提供了基于纤维素的大分子引发剂，平均每个双葡萄糖单元有一个引发位点。通过在 LiCl/DMAc 溶剂系统中用 2-BiBB 酰化微晶纤维素 (MCC)，制备平均每个重复双葡萄糖单元多达 6 个起始位点的 ATRP 大引发剂。采用分级沉淀法得到了一系列具有窄MWD的线性大分子引发剂。通过元素分析确定引发位点的含量。然后从纤维素基大分子引发剂接枝（甲基）丙烯酸酯侧链。所制备的纤维素基聚合物刷显示出可调节的降解率，具体取决于刷的接枝密度，遵循两种不同的降解途径，即主链断裂或侧链分离。 © 2019 Wiley periodicals, Inc. J. Polym。科学，A 部分：聚合物。化学.2019,57, 2426–2435
Cellulose‐based polymer brushes with variable grafting densities and low dispersity were synthesized by grafting poly(n‐butyl acrylate) (PBA) side chains from cellulose‐derived backbones via ATRP. Esterification of commercially available cellulose acetate with 2‐bromoisobutyryl bromide (2‐BiBB) in NMP provided cellulose‐based macroinitiators averaging one initiation site per double glucose unit. ATRP macroinitiators averaging up to 6 initiation sites per repeating double glucose unit were prepared by acylation of microcrystalline cellulose (MCC) in LiCl/DMAc solvent system with 2‐BiBB. A series of linear macroinitiators with narrow MWD were obtained by fractional precipitation process. The content of initiating sites was determined by elemental analysis. (Meth)acrylate side chains were then grafted from the cellulose‐based macroinitiators. The prepared cellulose‐based polymer brushes showed tunable degradation rates dependent on grafting density of the brush, following two different degradation pathways, either cleavage of the main chain or detachment of the side chains. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.2019,57, 2426–2435