Sallat Aladdin, Das Amit, Schaber Jana, Scheler Ulrich, Bhagavatheswaran Eshwaran S, Stöckelhuber Klaus W, Heinrich Gert, Voit Brigitte, Böhme Frank
Leibniz Institut für Polymerforschung Dresden, Hohe Straße 6 D-01062 Dresden Germany
Organische Chemie der Polymere, Technische Universität Dresden D-01062 Dresden Germany.
RSC Adv. 2018 Jul 27;8(47):26793-26803. doi: 10.1039/c8ra04631j. eCollection 2018 Jul 24.
Rubber composites were prepared by mixing bromobutyl rubber (BIIR) with silica particles in the presence of 1-butylimidazole. In addition to pristine (precipitated) silica, silanized particles with aliphatic or imidazolium functional groups, respectively, were used as filler. The silanization was carried out either separately or during compounding. The silanized particles were characterized by TGA, H-Si cross polarization (CP)/MAS NMR, and Zeta potential measurements. During compounding, the bromine groups of BIIR were converted with 1-butylimidazole to ionic imidazolium groups which formed a dynamic network by ionic association. Based on DMA temperature and strain sweep measurements as well as cyclic tensile tests and stress-strain measurements it could be concluded that interactions between the ionic groups and interactions with the functional groups of the silica particles strongly influence the mechanical and viscoelastic behavior of the composites. A particularly pronounced reinforcing effect was observed for the composite with pristine silica, which was attributed to acid-base interactions between the silanol and imidazolium groups. In composites with alkyl or imidazolium functionalized silica particles, the interactions between the filler and the rubber matrix form dynamic networks with pronounced self-healing behavior and excellent tensile strength values of up to 19 MPa. This new approach in utilizing filler-matrix interactions in the formation of dynamic networks opens up new avenues in designing new kinds of particle-reinforced self-healing elastomeric materials with high technological relevance.
通过在1-丁基咪唑存在下将溴化丁基橡胶（BIIR）与二氧化硅颗粒混合来制备橡胶复合材料。除了原始（沉淀）二氧化硅外，分别具有脂肪族或咪唑鎓官能团的硅烷化颗粒用作填料。硅烷化反应可以单独进行，也可以在混炼过程中进行。通过热重分析（TGA）、H-Si交叉极化（CP）/魔角旋转（MAS）核磁共振以及Zeta电位测量对硅烷化颗粒进行了表征。在混炼过程中，BIIR的溴基团与1-丁基咪唑反应转化为离子型咪唑鎓基团，这些基团通过离子缔合形成动态网络。基于动态热机械分析（DMA）温度和应变扫描测量以及循环拉伸试验和应力-应变测量，可以得出结论，离子基团之间的相互作用以及与二氧化硅颗粒官能团的相互作用强烈影响复合材料的力学和粘弹性行为。对于含有原始二氧化硅的复合材料，观察到了特别显著的增强效果，这归因于硅醇基团和咪唑鎓基团之间的酸碱相互作用。在含有烷基或咪唑鎓官能化二氧化硅颗粒的复合材料中，填料与橡胶基体之间的相互作用形成了具有显著自愈行为和高达19 MPa优异拉伸强度值的动态网络。这种在动态网络形成过程中利用填料-基体相互作用的新方法为设计具有高技术相关性的新型颗粒增强自愈弹性体材料开辟了新途径。
