Composites and nanocomposites
A polymer composite is a multi-component material in which reinforcing fillers are integrated with a polymer matrix, contributing to harmonious mechanical properties that are different from the individual components’ features.
In a similar context, a polymer nanocomposite is a composite material containing a polymer or a copolymer with nanostructured particles or nanofillers, mixed or dispersed in the polymer matrix phase. The fillers can be layered materials, fibers or particles embedded in a wide variety of natural or synthetic polymers. Actually, the idea behind nanocomposites is the utilization of building blocks in nanometer scale to design innovative materials with unique verstaility and ameliorated physical properties.
Polymer nanocomposites are possibly one the most multipurpose materials today, utilized in almost every area of life counting biomedicine, automotive, aerospace, electronics, electrical, sports, marine, energy, etc.​
In Bikiaris Lab, we search efficient ways to significantly improve the properties of several polymeric matrices after the incorporation of various nanofillers.
Our research activity covers the design, synthesis and characterization of nanocomposite polymers, and though, explores the effect of the added fillers to the final thermal and mechanical material’s properties.
The most frequently used synthesis techniques, including ultrasonication-assisted solution mixing, in-situ polymerization, melt mixing as well as other ex situ and in situ processing methods, are investigated in the context of their applicability, the controlling parameters, and the scale-up dynamic for industrial applications.
Polymer nanocomposites are applicable in modern fields and could be divided into two main categories:
1. Engineering purposes
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Fillers augment specific properties of polymers and polymer nanocomposites, particularly based on nanoclays, which have received wide attention due to their ability to improve mechanical, thermal, barrier and fire-retardant properties of polymers. It has been found that these materials have properties equal to or better than those of polymer composites with conventional filler.
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Inorganic nanoscale fillers, which are viewed as being very important, include layered silicates (such as montmorillonite), nanotubes (mainly carbon nanotubes, CNTs), SiO2, metal oxides (e.g., TiO2, Fe2O3 Al2O3), nanoparticles of metals (e.g., Au, Ag), semiconductors (e.g., PbS, CdS), carbon black, nanodiamonds, etc.
Some related achievements of Bikiaris group at this field, are the synthesis of:
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polymer nanocomposites based on poly(butylene 2,5-furan dicarboxylate) (PBF) and clay nano-inclusions via the in-situ transesterification and polycondensation method
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polymer nanocomposites (PNCs) based on a poly(propylene furanoate) (PPF)
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polypropylene-random-copolymer (PPR) nanocomposites with multi-walled carbon nanotubes (MWC-NTs) and nanodiamonds (NDs) in various concentrations, to study the effects of the nanoparticles on the thermal behavior of PPR
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poly(ε-caprolactone) (PCL) reinforced with amino-functionalized multi-walled carbon nanotubes (f-MWCNTs), by an in situ ring opening polymerization (ROP) procedure
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polymer composites based on poly(lactic acid) (PLA) and three fillers, graphene oxide (GO), silica nanoparticles, and a nanohybrid consisting of silica doped GO
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HDPE nanocomposites containing different amounts of copper nanofibers,by melt mixing
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poly(butylene succinate) (PBSu) reinforced with nanofillers of different shapes, sizes and geometries such as silver, silica (SiO2), multi-walled carbon nanotubes (MWCNTs) and graphene oxide (GO).
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poly(butylene naphthalate) (PBN) and its nanocomposites containing pristine multi-walled carbon nanotubes (MWCNTs), as well as functionalized MWCNTs with amino and carboxyl groups (MWCNTs-NH2 and MWCNTs-COOH), in situ prepared by applying the melt polycondensation method
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different series of HDPE nanocomposites by melt mixing, containing 2.5 wt% of multiwall carbon nanotubes, pristine and modified montmorillonite, and SiO2 nanoparticles
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HDPE composites containing different concentrations of silver (Ag) nanoparticles (0.5%, 1%, 2%, 3%, and 5 wt%), by melt mixing
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in situ introduced to poly(propylene furanoate) PPF matrix low amounts of carbon nanotubes (CNT) and graphene oxide (GO) platelets
2. Biomedical applications
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Polymer nanocomposites have great potential in different biomedical applications. Biodegradation is an important aspect in such applications, which can be controlled through the incorporation of suitable nanomaterials in the desired polymer matrices. Biodegradable and biocompatible polymer nanocomposites are dynamic potential candidates in the field of biomedical science as implantable materials, scaffold materials, materials for tissue engineering, drug delivery vehicles, antimicrobial materials, biosealant, etc.
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One area of intense research involves electrospinning for the production of bioresorbable nanofiber scaffolds for tissue engineering, biodegradable surgical sutures, stent, and other applications.
In our research team, we have developed bio-composite polymeric systems with ameliorated biological properties, such related attempts are:
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the incorporation of bioactive ceramics with similar microstructure to native bone structure, into poly(butylene succinate) (PBSu), for greater bioactivity and new bone growth enhancing bone formation
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synthesis and integration of mesoporous bioactive glasses (SiO2-CaO-P2O5 and SiO2-SrO-P2O5) into PCL thin membranes, by spin coating
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high surface area drug-laden mesoporous silica foam with cellular pore morphology (MCF), entrapped in PLA and PLGA copolymer microspheres, used for injectable drug delivery
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high surface area mesoporous silica (SBA-15) loaded with anticancer agent and further entrapped into poly(lactic acid-co-glycolic acid) (PLGA) microparticles (MPs) for drug delivery purposes
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PBSu nanocomposites containing strontium hydroxyapatite [Sr5(PO4)3OH] nanorods (SrHAp nrds), prepared by in situ polymerization.