Oberhausen Bastian, Kickelbick Guido
Saarland University, Inorganic Solid-State Chemistry Campus, Building C4.1 66123 Saarbrücken Germany
Nanoscale Adv. 2021 Aug 5;3(19):5589-5604. doi: 10.1039/d1na00417d. eCollection 2021 Sep 28.
Supramolecular interactions represent versatile, reversible, and intrinsic mechanisms for bond formation after the failure of materials. Ionic interactions excel through high flexibility and binding strength. In this study, ionic interactions between polymer matrices and inorganic nanoparticles were used to induce self-healing properties. Random, anionic polyelectrolyte copolymers consisting of di(ethylene glycol) methyl ether methacrylate and sodium-4-(methacryloyloxy)butan-1-sulfonate were synthesized by atom transfer radical polymerization. Differential scanning calorimetry measurements confirmed the adjustability of the glass transition temperature the polymer composition. Within the glass transition temperature window of the homopolymers from -23 °C to 126 °C, the range between -18 °C to 50 °C was examined, generating suitable matrices for self-healing. Superparamagnetic iron oxide nanoparticles with a size of 8 nm were synthesized by thermal decomposition of iron(iii) acetylacetonate and used as the inorganic filler. Positive surface charges were introduced by functionalization with ,,-trimethyl-6-phosphonhexan-1-aminium bromide. Functionalization was confirmed with FTIR, TGA, and zeta potential measurements. Ionic interactions between filler and polymer promote a uniform particle dispersion within the material. Self-healing experiments were performed at 80 °C and without the addition of further healing agents. Utilizing the magnetic properties induced by the iron oxide nanoparticles, spatially resolved healing within an alternating magnetic field was achieved on a μm scale.
超分子相互作用是材料失效后形成键的通用、可逆和固有机制。离子相互作用具有高灵活性和结合强度，表现出色。在本研究中，聚合物基体与无机纳米粒子之间的离子相互作用被用于诱导自修复性能。通过原子转移自由基聚合合成了由二（乙二醇）甲基醚甲基丙烯酸酯和4-（甲基丙烯酰氧基）丁烷-1-磺酸钠组成的无规阴离子聚电解质共聚物。差示扫描量热法测量证实了玻璃化转变温度随聚合物组成的可调性。在均聚物-23℃至126℃的玻璃化转变温度窗口内，研究了-18℃至50℃的范围，生成了适合自修复的基体。通过乙酰丙酮铁（III）的热分解合成了尺寸为8nm的超顺磁性氧化铁纳米粒子，并用作无机填料。通过用溴化，，，-三甲基-6-膦酰己烷-1-铵功能化引入正表面电荷。通过傅里叶变换红外光谱、热重分析和zeta电位测量证实了功能化。填料与聚合物之间的离子相互作用促进了材料内颗粒的均匀分散。自修复实验在80℃下进行，且未添加其他愈合剂。利用氧化铁纳米粒子诱导的磁性，在交变磁场中实现了微米尺度的空间分辨愈合。
