Ikeda Junko, Kurihara Tomoki, Ogura Keiju, Akama Shota, Kawai Mika, Mitsumata Tetsu
Graduate School of Science and Technology, Niigata University, Niigata 950-2181, Japan.
Gels. 2021 May 6;7(2):56. doi: 10.3390/gels7020056.
The relationship between rheological features in the absence of a magnetic field and magnetic response was investigated for κ-carrageenan magnetic hydrogels containing carbonyl iron particles. The concentration of carrageenan was varied from 1.0 to 5.0 wt%, while the concentration of carbonyl iron was kept at 70 wt%. The magnetic response revealed that the change in storage modulus Δ decreased inversely proportional to the carrageenan concentration. A characteristic strain γ where ' equals to ″ was seen in a strain range of 10. It was found that Δ' was inversely proportional to the characteristic stress at γ. Another characteristic strain γ where the loss tangent significantly increased was also analyzed. Similar to the behavior of γ, Δ' was inversely proportional to γ. The characteristic stresses at γ and γ were distributed at 80-720 Pa and 40-310 Pa, respectively. It was revealed that a giant magnetorheology higher than 1 MPa can be observed when the characteristic stresses at γ and γ are below approximately 240 Pa and 110 Pa, respectively.
研究了含羰基铁颗粒的κ-卡拉胶磁性水凝胶在无磁场时的流变特性与磁响应之间的关系。卡拉胶浓度在1.0至5.0 wt%之间变化，而羰基铁浓度保持在70 wt%。磁响应表明，储能模量的变化Δ与卡拉胶浓度成反比。在10的应变范围内观察到一个特征应变γ，此时“等于”“。发现Δ'与γ处的特征应力成反比。还分析了另一个损耗角正切显著增加的特征应变γ。与γ的行为类似，Δ'与γ成反比。γ和γ处的特征应力分别分布在80 - 720 Pa和40 - 310 Pa。结果表明，当γ和γ处的特征应力分别低于约240 Pa和110 Pa时，可以观察到高于1 MPa的巨磁流变效应。
