| Autor: |
Zhou Y; Chair of Materials Science, Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Löbdergraben 32, 07743 Jena, Germany.; School of Materials Engineering, Xi'an Aeronautical University, Xi'an 710077, P.R. China., Firkowska-Boden I; Chair of Materials Science, Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Löbdergraben 32, 07743 Jena, Germany., Arras MML; Chair of Materials Science, Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Löbdergraben 32, 07743 Jena, Germany., Jandt KD; Chair of Materials Science, Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Löbdergraben 32, 07743 Jena, Germany.; Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Philosophenweg 7, 07743 Jena, Germany. |
| Abstrakt: |
Block copolymers (BCPs) have previously been identified as powerful multiwalled carbon nanotube (MWCNT) dispersants in solution. However, relatively high costs and limited dispersibility hinder the use of BCPs in large-scale practical applications. Partial replacement of BCP with a low-cost homopolymer (HP) offers a promising approach to produce cost-effective MWNCT dispersions. The effect of HP/BCP blends on MWNCT dispersion degree and stability has yet to be elucidated. In this work, we tested the hypothesis that HP-induced BCP micelle size variation affects MWCNT dispersibility. Here, blends of the BCP poly(styrene)- block -poly(2-vinylpyridine) and the HP polystyrene (PS) were applied to examine BCP micelles' size dependence on the MWCNT dispersion degree. Light microscopy results showed that using HP/BCP blends, MWCNT dispersion was enhanced by up to 263% compared to pure BCP at a constant weight ratio of BCP to MWCNTs. Based on the correlation of increased MWCNT dispersion degree with increased BCP micelle size, as revealed by dynamic light scattering, an MWCNT dispersion mechanism is proposed. The mechanism includes a rationale for the unexpected finding that HP PS swells the BCP micelle's PS corona in a good solvent for PS. Using HP to increase MWCNT dispersion is a promising approach with possible applications in the production of high-performance composite materials. This holds especially for formulations of practical relevance where often (BCP) dispersants are only one of many components in the material. |
