Alberto Maceiras

• PhD in Materials Science
• Research technician at Basque Center for Materials, Applications and Nanostructures

Alternating different donor-acceptor monomers, conjugated polyimides (PI) are successfully synthesized by chemical imidization through in situ silylation of diamines. A detailed photophysical characterization is performed in the monomers and different polymers in tetrahydrofuran solutions. The emission spectra of the related donor-acceptor polymers...

The use of polymer based magnetoelectric materials for sensing and actuation applications has been the subject of increasing scientific and technological interest. One of the drawbacks to be overcome in this field is to increase the temperature range of application above 100 °C. In this way, a nanocomposite material composed by a mixture of two aro...

A series of amorphous polyimides and copolyimides that contained nitrile were obtained by a two-step procedure. The first step consisted of a polycondensation reaction of 4,4’-oxydiphtalic anhydride (ODPA) with one or two aromatic diamines, namely 1,3-Bis-2-cyano-3-(3-aminophenoxy)phenoxybenzene (diamine 2CN) and 1,3-Bis(3-aminophenoxy)benzene (dia...

A thermal protection system is subject to high forces, in particular compression, bending and wear, to aggressive environments of high temperatures, high velocity gases and particle shock. Typically, ceramic materials appear as a first barrier or outer shield over a metallic substrate responsible for the structure. When it comes to a coating due to...

Three composite materials with different CaZrO3/MgO fractions (2/3, 1/2, 1/3) and two single-phase materials (CaZrO3 and MgO) were fabricated and their thermal conductivity was investigated. Complete thermal and mechanical characterizations (thermal expansion coefficient, thermal diffusivity, specific heat, hardness and toughness) of the materials...

One of the most relevant problems of nano-reinforced resins is the uniform dispersion of nanoparticles. This problem is even more relevant when they are involved in the production of laminated composites. In this case, in addition to the agglomeration of nanoparticles, air bubbles are also very frequent during the manufacturing process of laminated...

Olives’ consumption produces copious agricultural byproducts that have accompanied humanity for millennia, but the increasing worldwide production complicates its management. Most wastes are generated during olive oil production in form of olive stones and other lignocellulosic derivatives. Industrial processes of chemical or physical nature to rec...

Epoxy with carbon nanofibers (CNFs) are effective nano enhanced materials that can be prepared by easy and low-cost method. The present paper compares the improvements, in terms of flexural and viscoelastic properties, of two epoxy resins reinforced with different weight percentages (wt.%) of CNFs. These epoxy resins have different viscosities, and...

Multifunctional composites can be achieved by adding two different fillers with complementary properties to a polymer matrix. In this work, novel tri-composite multifunctional materials based on the incorporation of dielectric BaTiO3 (BT) and magnetic CoFe2O4 (CFO) nanoparticles into poly(vinylidene fluoride) (PVDF) have been developed with enhance...

Thermosetting polymers are very popular in the automotive and aeronautic industry, in particular epoxy resin is widely used as matrix thermoset in carbon and glass fibre reinforced composites. The properties of these epoxy-based polymers can be improved with the addition of particulate or small fibre materials in order to construct a lightweight ma...

Starting from synthetic raw materials (CaZrO3 and MgO), microstructural and mechanical properties were optimized in order to obtain dense multiphasic ceramic, then finite element method (FEM) of an equimolar (1:1) CaZrO3-MgO composite was performed in order to obtain the effective elastic modulus. Composite presents two main phases of orthorhombic...

Cellulose nanocrystals (CNCs) were incorporated into poly (vinylidene fluoride) (PVDF) to tailor the mechanical and dielectric properties of this electroactive polymer. PVDF/CNC nanocomposites with concentrations up to 15 wt.% were prepared by solvent-casting followed by quick vacuum drying in order to ensure the formation of the electroactive γ-ph...

Poly(vinylidene fluoride) (PVDF), poly(vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE), poly(vinylidene fluoride-co-hexafluropropylene) (PVDF-HFP) and poly(vinylidene fluoride-co-chlorotrifluoroethylene) (PVDF-CTFE) were evaluated for the development of ionic liquid (IL) - polymer composite bending actuators. The selected guest IL, 1-ethyl-3-...

Conducting polymer composites are increasingly investigated for the development of piezoresistive materials for sensor applications due to their outstanding electromechanical properties. In this work, the effect of different surfactants on the piezoresistive response of triblock copolymer styrene-butadiene-styrene (SBS)/carbon nanotubes (CNT) compo...

Biomaterials processed in the form of electrospun fiber mats have already been explored to mimic different types of extracellular matrix in the human body once human body shows both aligned and randomly oriented cell/tissues. Knowing that numerous cell functions are regulated by mechanical signals, it is of key importance to quantitatively taken in...

CoFe2O4 (CFO) ferrite nanoparticles with an average size of 15 nm were synthesized by a hydrothermal method and used to develop magnetodielectric (MD) composites with the piezoelectric diamine 2CN/diamine 0CN as polymer matrix. It is shown that the dielectric constant, dielectric loss, and saturation magnetization values of the composites increase...

Separator membranes based on poly(vinylidene fluoride), PVDF, poly(vinylidene fluoride-co-trifluoroethylene), PVDF-TrFE, poly(vinylidene fluoride-co-hexafluropropylene), PVDF-HFP and poly(vinylidene fluoride-co-chlorotrifluoroethylene), PVDF-CTFE were prepared by solvent casting method using N,N-dimethylformamide (DMF) as solvent. In all cases, the...

A magnetic cellulosic material composed of cellulose nanocrystals (CNC) and cobalt ferrite (CoFe2O4) nanoparticles was developed through evaporation-induced self-assembly (EISA). Nanoparticles demonstrated good dispersibility within the cellulose nanocrystal template. The addition of glucose to CNC network allows the development of homogeneous crac...

This chapter reviews the different types of piezoelectric polymers that can be used as piezoelectric elements in magnetoelectric (ME) composites for high temperature applications. It then explains the main characteristics of each polymer, their main advantages and disadvantages. Ramadan et al. classified piezoelectric polymers based on their operat...

Three polyimide membranes (polymer 0CN, copolymers 0CN/2CN (50/50) and polymer 2CN), with and without CN dipolar groups, have been prepared by electrospinning and evaluated as lithium-ion battery separators. The prepared membranes show average fiber diameters between 0.5 and 1.09 μm and a degree of porosity of ~ 80%. The thermal stability, uptake,...

Poly(vinylidene fluoride), PVDF, has been blended with different ionic liquids (IL) in order to evaluate the effect of the different IL anions and cations on the electroative β -phase, thermal, mechanical and electrical properties of the polymer blend. [C2MIM][Cl], [C6MIM][Cl], [C10MIM][Cl], [C2MIM][NTf2], [C6MIM][NTf2], [C10MIM][NTf2] have been se...

Polyimide copolymers have been prepared based on different diamines as comonomers: a diamine without CN groups and a novel synthesized diamine with two CN groups prepared by polycondensation reaction followed by thermal cyclodehydration. Dielectric spectroscopy measurements were performed, and the dielectric complex function, ac conductivity and el...

Magnetoelectric response at the radio frequency range has been studied as a function of temperature. For that purpose, we have fabricated sandwich-type laminated composites in which the Fe61.6Co16.4Si10.8B11.2 alloy was used as the magnetostrictive element and polyvinylidene fluoride (PVDF) as the piezoelectric one. The Fe61.6Co16.4Si10.8B11.2 amor...

Piezoelectricity in amorphous polymers is mainly due to the orientation polarization of the molecular dipoles. Aromatic polyimides are high-performance polymeric materials possessing large molecular dipoles. We already reported good magnetoelectric performance of laminate composites with Vitrovac 4040 (R) as magnetostrictive component and the 2,6(b...