Coaxial electrospinning, polymer

Q. Zhao, Y. Xin, Z. Huang, S. Liu, C. Yang, and Y. Li, Using poly[2-methoxy-5-(2 -ethyl-hexyloxy)-l,4-phenylene vinylene] as shell to fabricate the highly fluorescent nanofibers by coaxial electrospinning. Polymer, 48,4311-4315 (2007). 

Poly[2-methoxy-5-(2 -ethyl-hexyloxy)-l,4-phenylene vinylene] (MEH-PPV) is an excellent conjugated polymer and broadly used in polymer photoelectron devices, but is difficult to electronspin directly. In the work by Zhao et al, core-shell structured nanofibers were fabricated by coaxial electrospinning MEH-PPV (shell) in chlorobenzene and PVP (core) in 1,2-dichloroethane [64]. MEH-PPV was soluble in the above two solvents, which prevented the precipitation of MEH-PPV and enhanced the adhering action between the two polymers in the coaxial electrospinning process. It should be noted that this is an unusual example of core-shell nanofibers where (a nonprocessable) PPV was spun as the shell and not in the core. These uniform core/shell PVP/MEH-PPV nanofibers with a highly fluorescent property can have potential applications in the fabrication of polymer nanophotoelectron devices. 

As reported in other chapters in this volume, PLA is one of the most used materials for biomedical applications due to biocompatibility and biodegradability, but hydrophobic properties require the encapsulation of water-soluble agents to avoid decomposition and failure of the polymer as a drug-carrier substrate. One of the advantages of coaxial electrospinning is that solid or liquid drugs can be incorporated into electrospun nanofibres and it is possible to encapsulate drugs into a structural shell. 

Finally, the coaxial electrospinning technique is suitable to prepare coreshell fibres with high-molecular-weight molecules, such as proteins, in-eorporated into them. In this case the formation of the high-molecular-weight fibres is aided by the electrospinning of homogenous polymer solutions. ... 

Yu D G, Branford-White C, White K, Chatterton N P, Zhu L M, Huang L Y and Wang B (2011) A modified coaxial electrospinning for preparing fibers from a high concentration polymer solution,... 

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