| With the advancement of society, development of science and application of high-tech, there is need for materials with better performance. This kind of materials should not only exhibit the enhancement of the single performance, but also exhibit the combination of manifold functions. One of efficient ways to achieve this aim is forming composite materials. Recently, due to their unique structure and excellent properties, carbon nanotubes have triggered considerable interest in the fields of physics, chemistry and material science. In addition, the organic or polymeric magnetic materials have received more and more attentions for their characteristics of structural diversity, low density, easy process and the controllable magnetic feature in the submolecular level. If it were possible to chemically combine carbon nanotubes and organic ferromagnet, this would afford novel materials that can not only possess strongpoints of both components, but also have the effective combination of various functions. The novel materials with electric and magnetic properties will have great application prospect in many areas such as ultrahigh frequency equipments, high density memory materials, microwave-absorbing materials, micromation of electron products, universe sail systems, etc. So, the synthesis and study of novel organic magnets containing carbon nanotubes is of great theoretical significance in the fields of magnetic materials and nano-sicience.The development and status in quo of carbon nanotubes and organic magnetic materials have been reviewed in this paper. The main purpose of this work is focused on finding new organic magnetic materials with better performance, studying the relationship between structure and properties, enriching the organic magnet theories. Therefore, carbon nanotubes-grafted polymer containing bithiazole rings and corresponding complexes were synthesized and their magnetic properties were investigated. Based on the analysis of magnetic data, a possible magnetic model was proposed to explain the phenomena of "magnetism transition". The major contributions of this paper are as follows:1. For the first time, a series of novel single-walled carbon nanotubes (SWNT) / poly(amic acid) (PAA) graft composites were synthesized, and their complexes were prepared using the capability of coordination from poly(amic acid) containing bithiazole rings. The magnetic properties and conductivity of complexes were measured as well. One of the important results in this work is that, this kind of materials possesses both ferromagnetic properties and conductivity, overcoming the non-magnetic property of carbon nanotubes and utilizing the good conductivity of carbon nanotubes. Magnetic measurement also shows that there exists magnetic interaction between introduced magnetic ions in the system, and the complexes SWNT-PAA-Mn+ (Mn+=Fe2+, Nd3+) have a relative high magnetization (M). Furthermore, the magnetic status has a relationship with the sort and content of metal ions.2. Novel composites of SWNT-connected heteroaromatic poly(schiff base) were synthesized, and two complexes, SWNT~TAPDA-Nd3+and SWNT-PDTEN -Nd3+, were prepared through polymers coordinating with NdCb, respectively. Their magnetic properties were investigated, especially the complex SWNT-PDTEN-Nd3+, by analysis the curves of magnetization versus temperature (M-T) and the curves of magnetization versus applied field (M-H). The magnetic data indicate the structure which polymer donor ligands incorporate rare earth ions into the main chain will be of benefit to the magnetic coupling between rare earth ions and forming the magnetic order state. SWNT-PDTEN-Nd3+ exhibits soft-ferromagnetic properties with a coercive field of 165 Oe and a remnant magnetization of 0.008 emu/g. Non-normal magnetic phenomena were observed that SWNT -PDTEN-Nd3+ is ferromagnetic at T < 125 K and turns to diamagnetic at T > 125 K. The ferromagnetism of polymeric complexes directly turns to diamagnetism at a transition temperature, which does not follow the behaviors of...
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