Nanocomposites and nanomaterials

Polymeric biocomposites ordered using magnetostatic field: a review 
Bolbukh Yu., Kozakevych R., Tertykh V.
Chuiko Institute of Surface Chemistry, NAS of Ukraine,
17 General Naumov Str., Kyiv 03164, Ukraine
E-mail: yu_bolbukh@yahoo.com

The investigation goal was elaboration of effective carriers of biological active substrate and coatings for stents or scaffolds based on filled polymers or co-polymers. An ideal scaffold for biomedical applications as known should be a three-dimensional constitution that is highly porous to guarantee oxygen permeability, sufficient nutrient transport to the cells, and removal of waste products. Additionally, the scaffold should have mechanical properties suitable for the in vivo tissue at the site of implantation and should be easily connected to the vascular system of the host. That’s why an orderly structure is essential characteristic of polymeric composites filed with nanotubes. One approach to solving this task is use of an external influence, such as magnetostatic field. 
The poly(2-hydroxyethylmethacrylate) (pHEMA) had been successfully applied as biomedical materials in plastic surgery, ophthalmology, and drug delivery because its excellent mechanical properties and high hydrophilicity made it suitable for conversion into different architectures. Unfortunately, pHEMA hydrogels are not biodegradable and are typically inserted into the body by surgical means, limiting their widespread application. Chitosan, a biodegradable, naturally occurring polymer, is especially attractive as a bone scaffold material because it supports the attachment and proliferation of osteoblast cells as well as formation of mineralized bone matrix.
In this review, we discuss the unique properties of chitosan and pHEMA films as a scaffolding material. We present the common methods for fabrication and characterization of scaffolds, and discuss the influence of material preparation on polymeric composite properties such as thermal degradation, mechanical strength, conductivity. Several types of polymeric materials based on chitosan or/and 2‑hydroxyethylmethacrylate (HEMA) and carbon nanotubes (MWCNT) were synthesized and tested. Polymeric composites have been prepared by desperation of carbon nanotubes into the monomer HEMA or the chitosan solution. Obtained materials were characterized using FTIR, ATR, DSC and TMA analysis. Beside this all materials were tested on conductivity.