Keskin Damla, Clodt Juliana I, Hahn Janina, Abetz Volker, Filiz Volkan
Institute of Polymer Research, Helmholtz-Zentrum Geesthacht , Max-Planck-Str. 1, 21502 Geesthacht, Germany.
Langmuir. 2014 Jul 29;30(29):8907-14. doi: 10.1021/la501478s. Epub 2014 Jul 14.
The surfaces of polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) diblock copolymer membranes were modified in order to obtain polymer brushes by using surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP). Isoporous membranes were prepared by the combination of self-assembly of PS-b-P4VP diblock copolymers and the nonsolvent induced phase separation process, also known as "phase inversion". In order to allow further functionalization, the membranes were modified with an ATRP initiator, 2-bromoisobutyryl bromide (BIBB). Therefore, the mussel-inspired poly(dopamine) coating was used to attach BIBB on the membranes surface. In the next step the coated membranes were postmodified by using surface-initiated ARGET ATRP with the hydrophilic monomer 2-hydroxyethyl methacrylate (HEMA). HEMA as a hydrophilic methacrylate was chosen for the modification in order to enhance the membrane characteristics and to obtain a surface with antifouling properties. The surface-initiated ARGET ATRP reaction was carried out using different reaction times and environments. PHEMA could successfully incorporate on the membrane surface as confirmed by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), (1)H nuclear magnetic resonance spectroscopy ((1)H NMR), scanning electron microscopy (SEM), and contact angle measurements. Furthermore, stability tests against heat and solvents were performed, and water flux was measured for the raw and modified membranes. Stability against heat and hydrophilicity could be increased with this type of modification for diblock copolymer membranes.
为了通过使用由电子转移原子转移自由基聚合（ARGET ATRP）再生的表面引发剂来获得聚合物刷，对聚苯乙烯-嵌段-聚（4-乙烯基吡啶）（PS-b-P4VP）二嵌段共聚物膜的表面进行了改性。通过PS-b-P4VP二嵌段共聚物的自组装与非溶剂诱导相分离过程（也称为“相转化”）相结合制备了等孔膜。为了实现进一步功能化，用ATRP引发剂2-溴异丁酰溴（BIBB）对膜进行改性。因此，采用受贻贝启发的聚多巴胺涂层将BIBB附着在膜表面。在下一步中，使用表面引发的ARGET ATRP，用亲水性单体甲基丙烯酸2-羟乙酯（HEMA）对涂覆的膜进行后改性。选择HEMA这种亲水性甲基丙烯酸酯进行改性，以增强膜的性能并获得具有防污性能的表面。表面引发的ARGET ATRP反应在不同的反应时间和环境下进行。衰减全反射傅里叶变换红外光谱（ATR-FTIR）、核磁共振氢谱（¹H NMR）、扫描电子显微镜（SEM）和接触角测量证实，PHEMA能够成功地结合到膜表面。此外，还对原始膜和改性膜进行了耐热性和耐溶剂性稳定性测试，并测量了水通量。通过这种类型的改性，二嵌段共聚物膜的耐热性和亲水性可以得到提高。
