Novel macro-xanthate agents containing azo initiator and polyethylene glycol (PEG) were synthesized to prepare block copolymers via macromolecular design by an interchange of xanthate (MADIX) polymerization. In this system, the multifunctional agents were used as both macromolecular chain transfer agents and free radical sources. Polystyrene–polyethylene glycol–polystyrene (PS-PEG-PS) copolymers were prepared easily with molecular weight (M_n) from 23,000 to 43,000 g/mol by MADIX copolymerization of styrene using PEG-N = N-PEG (M_n, PEG = 600, 1000, 1500, and 3000 g/mol) as the macro-MADIX agents. In this process, the molar mass (M_n) increased over time for a controlled MADIX polymerization process, but the polydispersity varied slightly. The controlled polymerizations showed typical living properties, and polymers having low polydispersity (below Đ < 1.4) were obtained with well-defined macromolecular structures. As a result, the macro-MADIX agents and the azo-initiator macromolecules were performed successful formation of the block copolymers. The obtained block copolymers were characterized by gel permeation chromatography, differential scanning calorimetry, Fourier transform infrared spectroscopy, and hydrogen nuclear magnetic resonance (¹H NMR) spectroscopy.

合成了含有偶氮引发剂和聚乙二醇 (PEG) 的新型大黄原酸酯试剂，通过黄原酸酯 (MADIX) 交换聚合的大分子设计制备嵌段共聚物。在该系统中，多功能试剂既用作大分子链转移剂又用作自由基源。聚苯乙烯-聚乙二醇-聚苯乙烯 (PS-PEG-PS) 共聚物很容易制备，分子量 (M _n ) 为 23,000 至 43,000 g/mol，通过使用 PEG-N = N-PEG (M _n , PEG = 600、1000、1500 和 3000 g/mol) 作为大分子 MADIX 试剂。在这个过程中，摩尔质量（M _n) 对于受控的 MADIX 聚合过程，随着时间的推移而增加，但多分散性略有不同。受控聚合显示出典型的活性特性，并且获得了具有明确定义的大分子结构的具有低多分散性（低于 Đ < 1.4）的聚合物。结果，大分子 MADIX 试剂和偶氮引发剂大分子成功地形成了嵌段共聚物。所得嵌段共聚物通过凝胶渗透色谱、差示扫描量热法、傅里叶变换红外光谱和氢核磁共振（¹ H NMR）光谱表征。