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Sex: Female
Education:

  • Doctor of Philosophy in Materials Science and Engineering, University of the Philippines-Diliman, 2004
  • Master of Science in Materials Science and Engineering, University of New South Whales, Australia, 1997
  • Bachelor of Science in Chemical Engineering, FEATI University, 1978

Field of Specialization:
Mechanical Properties
Polymers
Material Characterization
Advanced Materials
Nanomaterials
SEM Analysis
X-ray Diffraction
Microstructure
Ceramics
Surface Engineering

Researches:

Article title: Surface Design of 3D-printed PEEK by Controlling Slicing Parameters
Authors: Carlo S. Emolaga, Shaun Angelo C. Arañez, Persia Ada N. de Yro, Jocelyn P. Reyes, Brigida A. Visaya, Blessie A. Basilia, and Rigoberto C. Advincula
Publication title: Mechanical Engineering and Robotics Research 11(3), 2022

Abstract:
Additive manufacturing of high-performance materials such as polyether ether ketone (PEEK) is constantly gaining attention because of its applications in diverse fields. PEEK is a semicrystalline thermoplastic that exhibits superior mechanical properties, biocompatibility, and wear resistance that makes it suitable for biomedical and other industrial applications. Most of these applications call for surface designs where roughness and porosity are a major consideration. In this study, PEEK samples with different surface designs were prepared by modifying slicing parameters such as wall line, infill density, and raster angle. The samples were printed using fused deposition modelling and were characterized using a non-destructive method, X-ray micro computed tomography (X-ray micro-CT). X-ray tomograms and void content analysis show that voids usually occur at the junction between the walls and the infill for all three designs. Reducing the infill travel path by adding inner walls resulted to higher defect volume ratio. Defect volume ratio increased from 0.06% to 0.36% after the addition of inner walls. Reduction in infill density further increased the defect volume ratio. These results show that different surface and internal designs can be prepared by modifying slicing parameters and its defects/void content can be readily evaluated by X-ray micro-CT.
Full text available upon request to the author

Article title: Effect of Fiber Loading on the Chemical, Structural and Mechanical Properties of 3D Printed Polylactic Acid/Abaca Microcrystalline Cellulose Composites
Authors: Cyron L. Custodio, Joel M. Cabañero, Marissa A. Paglicawan, Blessie A. Basilia
Publication title: Materials Science Forum 1041:3-9, August 2021

Abstract:
In an attempt to improve the physical properties of 3D printed poly lactic acid (PLA), this study aims to develop a microcrystalline cellulose fiber and observe the effects of fiber loading on the PLA/cellulose composites to the composition, crystallinity, morphology, and tensile properties of the resulting 3D printed material. Microcrystalline cellulose (MCC) have been extracted from indigenous raw abaca fibers and used as the fiber reinforcement for the PLA matrix. Composites of 1 and 3 wt% MCC fibers with PLA were processed using the twin-screw extruder to produce filaments. The resulting composite filaments were 3D printed utilizing the fused deposition modeling technology. FTIR, XRD, digital microscopy, and mechanical testing were used in characterizing the various 3D printed PLA/MCC composite. With the incorporation of cellulose, the PLA/MCC had up to 32% increase in tensile strength and 43% increase in modulus at just 3 wt% fiber loading due to the inherent high modulus of abaca cellulose. The MCC significantly influences the chemical, structural and mechanical properties of the 3D printed PLA/MCC composites.
Full text available upon request to the author

Article title: Characterization of Cellulose Acetate Based Scaffolds Derived from Kapok Fiber (Ceiba pentandra (L) Gaertn)
Authors: Sharyjel R. Cayabyab*, Josefina R. Celorico, Cyron L. Custodio, Blessie A. Basilia
Publication title: Key Engineering Materials 891:77-82, July 2021

Abstract:
Utilization of natural biopolymers has shown potential in generating innovations for tissue engineering applications. This study aims to fabricate scaffolds from cellulose acetate derived from kapok fiber. Cellulose is extracted from raw kapok fibers by alkali treatment and delignification then synthesized into cellulose acetate. Kapok cellulose acetate (KCA) is dissolved in dimethyl sulfoxide to fabricate the scaffold. Materials were characterized using Attenuated Total Reflectance – Fourier Transform Infrared (ATR-FTIR) spectrometer, X-ray diffractometer (XRD) and Differential Scanning Calorimeter (DSC). FTIR analysis has shown that cellulose was extracted from kapok and cellulose acetate was successfully synthesized. XRD analysis also confirmed the presence of cellulose acetate. Results have also shown that synthesized KCA seems to have higher crystallinity than commercially available cellulose acetate (CCA). The degree of substitution (DS) of KCA was found to be 2.85 which is close to the DS value of tri-substituted cellulose acetate. DSC analysis has shown lower glass transition temperature of 52.15°C but higher degradation temperature of 300.43°C than the CCA. Moreover, the values for the enthalpy of fusion for two endotherms of KCA (44.0556 J/g and 18.6946 J/g) are higher than the values for CCA by 344% and 261%, respectively; thus, indicating the higher degree of crystallinity for synthesized KCA samples.
Full text available upon request to the author

Article title: A Study on the Release of Nanoparticles to the Environment from Nano-Enabled Asphalt by Weathering Experiment
Authors: M J Llana, M S Tolentino, N C C Valeza, J P Reyes and B A Basilia
Publication title: IOP Conference Series Materials Science and Engineering 1117(1):012030, March 2021

Abstract:
Researches in the field of nanotechnology is continuously gaining a lot of interest due to its wide range of applications. This study focused on the incorporation of halloysite nanotubes (HNT's) on asphalt and on the investigation of the release of the said nanoparticles from the asphalt to the environment through accelerated weathering experiment. Two (2) samples were prepared: asphalt with HNT (A1) and asphalt only (A2). SEM-EDX results showed that A1 initially had nanoparticles on the surface which can be attributed to the added HNT. SEM images further showed the changes on the surface morphologies of A1 and A2 after accelerated weathering experiment. These changes can be further correlated to the intercalation and exfoliation reactions that happened on the surface of asphalt during UV irradiation. Release studies revealed that Al and Si nanoparticles were being released on the surface due to the layer by layer degradation of the asphalt matrix. Hence, continuous exposure of asphalt could result to further degradation of asphalt, leading to the surfacing and release of more nanoparticles.
Full text link https://tinyurl.com/249p42ud

Article title: Release Analysis of Nano-Titanium Dioxide (TiO 2 ) from Paint: An Accelerated Weathering Experiment
Authors: M J Llana, M S Tolentino, N C C Valeza, J P Reyes and B A Basilia
Publication title: IOP Conference Series Materials Science and Engineering 1117(1):012029

Abstract:
Engineered nanomaterials (ENM's), particularly TiO2 nanoparticles are being incorporated on paints due to their capabilities to enhance optical properties and to scatter UV radiation, which eventually protects the paint from discoloration. In this study, the release of these nano-TiO2 from paint was investigated. Two (2) types of paint were used, one containing pigment- and nano-TiO2 (P1), while the other only contains pigment-TiO2 (P2). The paints were subjected to accelerated weathering wherein the paints were exposed to cycles of UV irradiation and water condensation. The SEM-EDX results showed the distribution of the pigment- and nano-TiO2 on the surface of P1 and P2, and the changes in the morphologies before and after weathering. The photomicrograph revealed the formation of cracks on the surface of P1 brought about by the photocatalytic degradation due to the presence of nano-TiO2. Leachate samples were also collected weekly in the duration of the weathering test and were analysed using ICP-OES. The presence of Ti, which can be correlated to the release TiO2, on the samples was detected. The release of Ti from P1 and P2 showed a decreasing trend throughout the weathering experiment, having the following initial amounts of release: 1.38 mg/L and 2.10 mg/L for P1 and P2, respectively. Moreover, a graphical release mechanism for the nano-TiO2 release was conceptualized based on the results of the study. In general, potential release of nano-TiO2 from paints could happen since these TiO2 nanoparticles serve as a photocatalyst in the paint degradation when exposed to prolonged weathering conditions.
Full text link https://tinyurl.com/2p8reuue

Article title: Powder Loading Effects on the Physicochemical and Mechanical Properties of 3D Printed Poly Lactic Acid/Hydroxyapatite Biocomposites
Authors: Cyron L. Custodio, Phoebeliza Jane M. Broñola, Sharyjel R. Cayabyab, Vivian U. Lagura1, Josefina R. Celorico, and Blessie A. Basilia
Publication title: International Journal of Bioprinting 7(1):326, January 2021

Abstract:
This study presents the physicochemical and mechanical behavior of incorporating hydroxyapatite (HAp) with polylactic acid (PLA) matrix in 3D printed PLA/HAp composite materials. Effects of powder loading to the composition, crystallinity, morphology, and mechanical properties were observed. HAp was synthesized from locally sourced nanoprecipitated calcium carbonate and served as the filler for the PLA matrix. The 0, 5, 10, and 15 wt. % HAp biocomposite filaments were formed using a twin-screw extruder. The resulting filaments were 3D printed in an Ultimaker S5 machine utilizing a fused deposition modeling technology. Successful incorporation of HAp and PLA was observed using infrared spectroscopy and X-ray diffraction (XRD). The mechanical properties of pure PLA had improved on the incorporation of 15% HAp; from 32.7 to 47.3 MPa in terms of tensile strength; and 2.3 to 3.5 GPa for stiffness. Moreover, the preliminary in vitro bioactivity test of the 3D printed PLA/HAp biocomposite samples in simulated body fluid (SBF) indicated varying weight gains and the presence of apatite species’ XRD peaks. The HAp particles embedded in the PLA matrix acted as nucleation sites for the deposition of salts and apatite species from the SBF solution
Full text link https://tinyurl.com/2p45594x

Article title: Exploring the corrosion inhibition capability of FAP-based ionic liquids on stainless steel
Authors: Julius Kim A. Tiongson1, Kim Christopher C. Aganda4,Dwight Angelo V. Bruzon2, Albert P. Guevara4,Blessie A. Basilia4, Giovanni A. Tapang2and Imee Su Martinez
Publication title: Royal Society Open Science 7(7):200580, July 2020

Abstract:
Corrosion is clearly one of the more common causes of materials failure in stainless steel. To manage corrosion, chemical inhibitors are often used for prevention and control. Ionic liquids due to their hydrophobic and corrosion-resistant property are being explored as alternative protective coatings and anti-corrosion materials. In this particular study, ionic liquids containing functionalized imidazolium cations and tris(pentafluoroethyl)trifluorophosphate (FAP) anions were investigated for their ability to inhibit corrosion on stainless steel surfaces in acidic environment. Using surface characterization techniques, specifically scanning electron microscopy and energy-dispersive X-ray (EDX), the morphology and the elemental composition of the steel surfaces before and after corrosion were determined. Contact angle measurements were also performed to determine how these ionic liquids were able to wet the stainless steel surface. In addition, potentiodynamic studies were carried out to ensure that corrosion inhibition has occurred. Results show that these ionic liquids were able to inhibit corrosion on the stainless steel surfaces. This indicates promise in the use of these FAP-based ionic liquids for corrosion management in stainless steel.
Full text link https://tinyurl.com/35fjhh4m

Article title: Development and physico-chemical characterization of Polyvinylidene fluoride (PVDF) flat sheet membranes with antibacterial properties against E. coli and S. aureus
Authors: Jose Gabriel Escoria, Stephen Paolo Lanzanas, Kirstine Joy Berjamin, Marielle Hannah Caliolio1, Ericson Dimaunahan, Vivian Lagura, Lumen Milo and Blessie Basilia
Publication title: Journal of Physics Conference Series 1593(1):012042, July 2020

Abstract:
The use of silver-modified montmorillonite (Ag-MMT) nanoclay from local montmorillonite ore as an additive for the development of PVDF flat sheet membranes with antibacterial properties for use in water disinfection was the focus of this study. It covers the development of PVDF flat sheet membranes with Ag-MMT nanoclay. The physico-chemical characterization was done through XRD, AFM, contact angle measurement, and FE-SEM while the antibacterial properties against gram-positive S. aureus and gram-negative E. coli were through inhibition zone and contact inhibition assessment. XRD results showed exfoliation of the Ag-MMT nanoclay in the PVDF flat sheet membrane, with minimal intercalations and similar functional group interactions. AFM results showed an increased surface roughness for every increase in Ag-MMT nanoclay which correlates to the contact angle measurement of membranes, demonstrating high contact angle measurement and high hydrophobicity for rougher surfaces, showing high hydrophilicity for the 0.250% Ag-MMT nanoclay membrane with a contact angle of 79.5 degrees. FE-SEM results reveal the morphology of the membrane. All experimental membranes are negative in contact inhibition against E. coli and S. aureus . However, the Ag-MMT nanoclay has been found to have antibacterial properties with the formation of inhibition zones, showing a higher sensitivity against E. coli .
Full text link https://tinyurl.com/5n6m92bn

Article title: Synthesis and Characterization of Polycaprolactone(PCL)/Organo-Montmorillonite(O-MMT) Blendvia Solvent Casting
Authors: Rey Mark A. Ramos, Ruth R. Aquino, Marvin S. Tolentino, Elisa G. Eleazar, Blessie A. Basilia
Publication title: Materials Science Forum 998:255-260, June 2020

Abstract:
Polycaprolactone (PCL) is a hydrophobic, semi-crystalline polymer that has been broadly applied in long term implants, drug release applications, and in the tissue engineering field due to its availability, relatively inexpensive price and suitability for modification. Organo-montmorillonite (O-MMT) clay has been extensively used for various polymer-nanocomposite studies and widely used as adsorbent due to its high specific surface area. Most polymer clay nanocomposites are involved in biomedical applications such as in drug delivery systems and wound healing. In this study, O-MMT was incorporated to PCL via solvent casting, which resulted into film membranes that were characterized to identify its surface morphology, chemical structure, wettability, mechanical property, pore size, and antibacterial properties upon its varying concentrations. The SEM and FTIR results indicated the presence of both PCL and O-MMT within the membrane. The mechanical properties of the film membranes showed an improvement upon reaching an optimal point. An increase in pore size was determined relative to its hydrophilicity. The film membrane showed an antibacterial activity only at the higher concentrations of the O-MMT using the S. aureus strain. As such, the results showed that there is an improvement in the mechanical, wettability, water absorption and antibacterial properties of the PCL with the incorporation of the O-MMT, making it a viable candidate dressing material for wound healing.
Full text available upon request to the author

Article title: Fabrication of Polythiourea-Copper Complex Composite Membrane and its Anti-fouling Property
Authors: M T Margarito1,2, A B Beltran1, MA Promentilla1, A Orbecido1, B Basilia2, R Damalerio1 and U Bigol
Publication title: IOP Conference Series Materials Science and Engineering 778(1):012178, May 2020

Abstract:
A Composite Flat Sheet Membrane Containing Polythiourea-Copper (PTU-Cu) Complex was fabricated through a two-step phase separation involving complexation and/or crosslinking of the polymer by copper ions (Cu2+) on the first step and non-solvent induced phase separation on the second step. The surface topography of the membrane was analysed using Atomic Force Microscope (AFM) in non-contact mode. The incorporation of copper at the surface was confirmed through Scanning Electron Microscope-Energy Dispersive X-ray (SEM-EDX) mapping wherein other elements such as Sulfur (S), Carbon (C) and Oxygen (O) of the polymer were conducted. The fabricated membrane was rigid as shown by high value (about 2.15 GigaPascal) of measured Young's modulus using the Pinpoint Nanomechanical Analysis Mode of AFM. In addition, the surface charge and hydrophobicity were measured using the Electrostatic Force Microscope (EFM) and water contact angle respectively. The antifouling characteristics of the membrane was evaluated through antimicrobial membrane surface contact test wherein E. coli was used as test microorganism. Other membrane properties such as pore size distribution and pure water flux were measured using a porometer and a filtration apparatus.
Full text link https://tinyurl.com/bddsx843

Article title: Assessing the Performance of Thin-Film Nanofiltration Membranes with Embedded Montmorillonites
Authors: Micah Belle Marie Yap Ang, Amira Beatriz Gaces Deang, Ruth R. Aquino, Blessie A. Basilia, Shu-Hsien Huang, Kueir-Rarn Lee, and Juin-Yih Lai
Publication title: Membranes 10(5):79, April 2020

Abstract:
In this study, the basal spacing of montmorillonite (MMT) was modified through ion exchange. Two kinds of MMT were used: sodium-modified MMT (Na-MMT) and organo-modified MMT (O-MMT). These two particles were incorporated separately into the thin-film nanocomposite polyamide membrane through the interfacial polymerization of piperazine and trimesoyl chloride in n-hexane. The membrane with O-MMT (TFNO-MMT) has a more hydrophilic surface compared to that of membrane with Na-MMT (TFNNa-MMT). When various types of MMT were dispersed in the n-hexane solution with trimesoyl chloride (TMC), O-MMT was well-dispersed than Na-MMT. The poor dispersion of Na-MMT in n-hexane led to the aggregation of Na-MMT on the surface of TFNNa-MMT. TFNO-MMT displayed a uniform distribution of O-MMT on the surface, because O-MMT was well-dispersed in n-hexane. In comparison with the pristine and TFNNa-MMT membranes, TFNO-MMT delivered the highest pure water flux of 53.15 ± 3.30 L∙m−2∙h−1 at 6 bar, while its salt rejection for divalent ions remained at 95%–99%. Furthermore, it had stable performance in wide operating condition, and it exhibited a magnificent antifouling property. Therefore, a suitable type of MMT could lead to high separation efficiency.
Full text link https://tinyurl.com/yeykemur

Article title: Adsorptive removal of Ni 2+ ions in wastewater using electrospun cellulose acetate / iron-modified nanozeolite nanostructured membrane
Authors: M S Tolentino, R R Aquino, M R C Tuazon, B A Basilia, M J Llana and J A M C Cosico
Publication title: IOP Conference Series Earth and Environmental Science 344(1):012044, November 2019

Abstract:
Release of heavy metal contaminated wastewater is one of the major problems being encountered by many industries due to its hazardous effect on the ecosystem, specifically its negative impacts on human health. Although essential in small quantities, nickel (Ni) and other heavy metals could be very dangerous to human health when uptaken at high concentrations. In this regard, this undertaking focused on the fabrication of nanofibers of cellulose acetate (CA) with varying concentrations (0, 1.0, 1.2 and 1.4 wt%) of iron-modified nanozeolite (Fe-MNZ) through electrospinning technique for the adsorption of Ni ²⁺ ions in simulated wastewater. The membranes produced underwent different characterization techniques to determine the effect of Fe-MNZ addition on the nanofibers. FTIR result showed changes in the broadness of some bank peaks which signifies the interaction between CA and Fe-MNZ. SEM results showed increasing fiber diameter with increasing Fe-MNZ concentration having an 848.08 nm maximum diameter. Lastly, Freundlich isotherm and pseudo-first order kinetics govern the adsorption of the Ni ²⁺ ions, with the highest adsorption capacity of 7.46 mg Ni ²⁺ / g membrane.
Full text link https://tinyurl.com/2p8a8ze7

Article title: Antibacterial Activities of Zinc Oxide Nanostructures with Different Structures
Authors: Rolen Brian P. Rivera, Melchor J. Potestas, Ma. Reina Suzette B. Madamba, Rey Y. Capangpangan, Bernabe L. Linog and Blessie A. Basilia and Arnold C. Alguno
Publication title: Diffusion and Defect Data Pt.B: Solid State Phenomena 294:36, July 2019

Abstract:
We report on antibacterial activities of Zinc oxide (ZnO) with different structures. Fast furrier transform infrared spectroscopy ZnO nanostructures showed peaks in the range between 450-600 cm-1 indicating the successful growth through the presence of Zn-O stretching. On the other hand, impurities such as zinc complexes might be present due to the appearance of peaks at 1110 cm-1, 1390 cm-1 and 1506 cm-1. Furthermore, SEM images revealed that nanorods and sea-urchin like nanostructures are present in the produced ZnO nanostructures. Nanorods exhibit a better antibacterial response than the sea-urchin like structure. The change in structural morphology along with its purity has greatly influenced the area of bacterial inhibition zone during antibacterial testing.
Full text link https://tinyurl.com/bdzfkepj

Article title: Controlling the Growth of Zinc Oxide/Polyaniline Nanocomposites on Platinum-Coated Substrate for Possible Solar Cell Applications
Authors: Arnold C. Alguno, Katherine M. Emphasis, Melchor J. Potestas, Reynaldo M. Vequizo, Rey Y. Capangpangan, Bernabe L. Linog and Blessie A. Basilia
Publication title: Diffusion and Defect Data Pt.B: Solid State Phenomena 294:30, July 2019

Abstract:
We report on the growth of zinc oxide/polyaniline (ZnO/PANI) nanocomposites deposited on platinum (Pt)-coated glass substrate via chemical bath deposition and dip-casting technique is reported. Scanning electron micrographs of the nanocomposites revealed that etching of ZnO nanorods takes place during growth which turn into plate-like and distorted nanostructures. We found out that increasing the concentration of NH4OH triggered increase in nanostructure diameter. The surface morphology of nanocomposites significantly changed as the molar concentration of NH4OH precursor varies. Fast fourier transform infrared spectroscopy results showed the interaction of ZnO and PANI by observing the shift of peaks to the higher wavenumbers. The measured optical band gap of the nanocomposites are in good aggreement with the reported values.This result indicates that the grown ZnO/PANI nanocomposites is a good material for solar cell device.
Full text available upon request to the author

Article title: Functionalized Carbon-based Quantum Dots: Optical Characterization and Potential Application as Bio-fluorophore
Authors: R A T Cruz, A N Soriano, P A N de Yro, G M O Quiachon, C S Emolaga, M L M Ysulat1, U G Bigol and B A Basilia
Publication title: IOP Conference Series Materials Science and Engineering 559(1):012003, June 2019

Abstract:
Carbon quantum dots (CQDs), in comparison to heavy metal-based quantum dots offer renewable, non-toxic, low cost and easy synthesis production route while having excellent physicochemical properties for biomedical or environmental use. This paper discusses development and application of functionalized carbon quantum dots from glycerol as primary carbon source and tetraethylene pentamine as functionalizing agent. As-synthesized CQDs were characterized by Fourier Transform Infrared Spectrometer (FTIR), UV-Vis Spectrophotometer and Spectrofluorometer. FTIR spectra confirmed functionalization of resulting CQDs with emission wavelength peaks at 314.18 nm and 381.15 nm and observed strong blue luminescence under UV lamp. The performance of produced CQDs as bio-fluorophore for Gram-stained bacterial models was validated. Results indicated that CQDs can effect fluoresced images but a more distinct image can be observed on S. aureus compared to E. coli. An attachment mechanism of carbon quantum dots to the bacteria surfaces was also proposed here
Full text link https://tinyurl.com/2p86vujt

Article title: Nanostructured Membrane of Sodium Montmorillonite Reinforced Cellulose Acetate for Adsorption of Ca(II) and Mg(II) Ions in Hard Water
Authors: Ruth R. Aquino, Marvin S. Tolentino, Diana Jean C. Ramolete, Arra M. Calingasan, Minerhiza N. Dela Cruz, Blessie A. Basilia
Publication title: Key Engineering Materials 801:319-324, May 2019

Abstract:
Permanent hard water softening was conducted with the use of cellulose acetate (CA)/sodium montmorillonite (Na+-MMT) nanostructured membranes. Fabrication of the nanostructured membranes with various Na+-MMT loading (0%, 5%, 10%, 15%) was made possible by electrospinning technique, which was carried out at 25°C, 30 kV applied voltage, needle size of 25G and a tip to collector distance of 18 cm. The effect of Na+-MMT content on the morphology of the fiber was examined with the use of Scanning Electron Microscope (SEM). It was determined that increasing the Na+-MMT loading decreases the average fiber diameter. The molecular structure of the blend nanostructured membranes were investigated using Fourier Transform Infrared (FTIR) Spectroscopy and the existence of CA and Na+-MMT in the electrospun nanostructured membrane was confirmed. Better adsorption performance was observed for the blend with 15% Na+-MMT as compared to pure CA and maximum uptake rate was attained at 7 hours for pure CA and only 5 hours for CA/Na+-MMT (85%/15%) blend. Increasing the initial hard water concentration increases the driving force for diffusion and in turn increases adsorption capacity of both pure CA and the CA/Na+-MMT (85%/15%) blend. More so, the results of the experiment best fitted the pseudo-second order kinetic model and the Freundlich isotherm model. Integration of Na+-MMT in CA increases the surface area for adsorption of the nanostructured membrane, and thus, could be used as an effective adsorbent for hard water softening.
Full text available upon request to the author

Article title: Effect of Polysulfone/Organomontmorillonite Blends on Nanocomposite Membrane Properties
Authors: Ruth R. Aquino, Marvin S. Tolentino, Mira L. Esmalde, Dara Veromica B. Condol, Blessie A. Basilia
Publication title: Key Engineering Materials 801:331-336, May 2019

Abstract:
In this study, an organically modified montmorillonite (OMMT) hydrophilic clay was incorporated in PSf through non-solvent induced phase separation fabrication process to improve its properties. Afterwards, hand casting was done and the PSf/OMMT membranes produced were characterized to determine the effect of OMMT addition to its structural, mechanical and thermal properties, and hydrophilicity. Scanning electron microscope (SEM) images of the surfaces showed a denser surface as the OMMT content increases but the pores on the images were not pronounced unlike the SEM images of the cross-section which depicted spherical macrovoids for 1.0% while wider macrovoids were observed for 3.0% and 5.0% OMMT. The mechanical properties of the nanocomposite with clay content up to 3.0% were improved. The glass transition temperatures of the PSf/OMMT nanocomposites were lower than the pure PSf while no significant difference was observed for the melting point. By statistical analysis, the addition and variation of the clay concentrations has no significant effect to the thermal properties. The hydrophilicity of the membranes improved with the increasing OMMT concentration, but was found to be insignificant. The overall data gathered showed that the clay addition had improved characteristics compared to the pure PSf membrane, which implies that PSf/OMMT nanocomposite could be likely used in filtration applications.
Full text available upon request to the author

Article title: Adsorptive removal of lead (Pb 2+ ) ion from water using cellulose acetate/polycaprolactone reinforced nanostructured membrane
Authors: R R Aquino1,3, M S Tolentino1,3, R M P D Elacion1, R Ladrillono1, T R C Laurenciana1 and B A Basilia
Publication title: IOP Conference Series Earth and Environmental Science 191(1):012139, November 2018

Abstract:
Nanostructured membranes of cellulose acetate (CA) with various polycaprolactone (PCL) loadings (0%, 10%, 20% and 30%) were produced via electrospinning process for the removal of Pb²⁺ ion from wastewater. Optimized electrospinning parameters were utilized: voltage supply (30 kV), temperature (25 °C), tip to collector distance (18 cm) and needle size (25 G). Certain characterization techniques were used to investigate the effect of PCL addition on CA nanostructured membranes. The surface morphology was examined through Scanning Electron Microscopy (SEM), and chemical composition and molecular structure were determined using Scanning Electron Microscope - Energy Dispersive X-ray Spectroscopy (SEM-EDX) and Fourier Transform Infrared Spectroscopy (FTIR), respectively. Results showed that the incorporation of PCL in CA produced finer fiber diameter which gave the membrane a larger surface area; thus, increasing the adsorption sites. Based on the results, adsorption capacity was improved from 43.96 mg Pb²⁺/g of pure CA membrane to 70.50 mg Pb²⁺/g of CA/PCL doped membrane. Moreover, the results of this experiment best fitted the pseudo second-order kinetics, and the Freundlich isotherm which appropriately describe the adsorption process. CA membranes are widely used in several separation processes, and the results showed, its capability can be further enhanced by the incorporation of PCL to produce nanostructured membranes.
Full text link https://tinyurl.com/bdeztnsn

Article title: Preparation of cellulose acetate blended with chitosan nanostructured membrane via electrospinning for Cd 2+ adsorption in artificial wastewater
Authors: R R Aquino, M S Tolentino, S C S Amen, M A V Arceo, M E S Dolojan and B A Basilia
Publication title: IOP Conference Series Earth and Environmental Science 191(1):012137, November 2018

Abstract:
This study focused on using chitosan (CS) as the functional polymer in the cellulose acetate (CA) matrix to provide reactive ion exchange sites for heavy metal ions. Pure CA and CA/CS blends (wt % 95:5, 90:10 and 85:15) were electrospun to determine the most qualified blend for the adsorption experiment. The morphologies of the electrospun nanostructured membranes were investigated using Scanning Electron Microscopy. The average fiber diameter was found to decrease with increasing CS concentration. CA and CS interaction was confirmed using Fourier Transform Infrared Spectroscopy. Upon characterization, the blend with 15% CS had the best properties for the adsorption process. The adsorption capacities of pure CA and CA/CS blend at different membrane loading and initial concentration showed a significant increase from 67.25 mg Cd²⁺/g pure CA membrane to 110.48 mg/g CS doped membrane. The experiment revealed that the adsorption kinetics of pure CA and CA/CS blend for Cd²⁺ were described by the pseudo-second order reaction model. The adsorption isotherm data for Cd²⁺on the surface of pure CA and CA/CS blend best fit the Freundlich isotherm and can be used to describe adsorption of Cd²⁺. This study produced an innovative nanostructured membrane for the removal of Cd²⁺ in wastewater.
Full text link https://tinyurl.com/2p8fwsef

Article title: Fabrication and Characterization of Electrospun Polysulfone (PSf) / Halloysite (HAL) Nanocomposite Membrane
Authors: Ruth R. Aquino, Marvin S. Tolentino, Jeremiah C. Millare, Clarisse D. Balboa, Christine Julia B. Castro, Blessie A. Basilia
Publication title: Materials Science Forum 934:55-60, October 2018

Abstract:
Polysulfone (PSf) is one of the commonly used polymeric membrane materials due to its excellent properties. One of the major concern however is that PSf membranes are mostly hydrophobic in nature. The presence of fillers like halloysite nanotubes (HNTs) into the polymer matrix can decrease this hydrophobicity and may also alter some of its important properties. This study focused on the fabrication of nanofibrous membranes by electrospinning method and characterization using SEM, UTM and contact angle goniometer to determine the effect of HNT concentration to the membrane’s surface morphology, mechanical properties and wettability. Results showed that samples subjected at the highest voltage produced finer fibers. The initial addition of HNTs also creates fiber strands with smaller diameters until beading in the fibers due to perturbation of the polymer jet caused by the increased viscosity of the solution and particle agglomeration was observed at higher concentrations. In terms of response to mechanical load, the tensile strength was higher upon HNT integration showing an effective transfer of stress to the dispersed phase despite the morphological imperfections. The contact angle results showed a decrease in hydrophobicity at the highest HNT concentration reflecting the water-loving character of the filler. The overall data gathered showed that the addition of nanoclay improved the properties of PSf matrix making them a suitable material for different filtration applications particularly in water treatment systems.
Full text available upon request to the author

Article title: Dispersion and electrokinetics of scattered objects in ethanol-water mixtures
Authors: Jeremiah C. Millare and Blessie A.Basilia
Publication title: Fluid Phase Equilibria 481, October 2018

Abstract:
Scattered objects ranging from 100 to 300 nm were detected in ethanol-water mixtures at increasing concentrations – 10–90% v/v ethanol using a particle size analyzer. To evaluate the structural transitions, two mechanisms of nanostructure formation from previous studies were considered: (1) molecular clustering and (2) nanobubble formation. Measurement of particle counts, polydispersities and sub-micron particle diameters were made available with the Dynamic Light Scattering (DLS) system and high resolution of detectors on the equipment (as small as 1 nm under dilute conditions). The electrokinetic property of colloidal dispersion through its zeta potential was simultaneously determined using the Phase Analysis Light Scattering (PALS) function of the instrument. Results suggest that the structural changes can be rooted, starting from an accumulation and amphiphilic encapsulation of gaseous phases forming nanobubble-like clusters at initial additions of ethanol, followed by bigger, and mostly aggregated ethanol-water and ethanol-ethanol clusters at higher concentrations. An inflection in the measured particle counts and zeta potentials at about 20% v/v ethanol as may be caused by the substantial amount of nanobubble clusters was observed similar to the reported anomalous trend in the measured thermophysical properties of ethanol-water mixtures.
Full text available upon request to the author

Article title: Nanobubbles from Ethanol-Water Mixtures: Generation and Solute Effects via Solvent Replacement Method
Authors: Jeremiah C. Millare and Blessie A.Basilia
Publication title: ChemistrySelect 3(32):9268-9275, August 2018

Abstract:
Replacement of ethanol‐water solutions (70 – 100% v/v) with deionized water was performed in a flow cell of a particle size analyzer. The resulting alcohol solutions were found to contain bulk nanoscale bubbles due to air supersaturation as can be induced by the difference in gas solubility of the solvents. The effect of charged and polar solutes (salt and sugar) that may influence the formation and surface chemistry of nanobubbles was also determined. Dispersion characteristics such as hydrodynamic diameter, particle concentration, along with the particle‘s electrokinetic property were measured all at once using light scattering techniques after solution replacement with and without the solute species. Light scattering results showed that the resulting solutions upon exchange have higher particle quantities than the starting ethanol‐water solvents with smaller diameters ranging from 80 to 160 nm due to nanobubble formation. The claim for air supersaturation forming nanobubbles that may have resulted to the increase in particle density can also be deduced from the obtained optical images in a microscope. The electrokinetic potential or zeta potential was also higher for the solvent exchange protocols entailing for a selective orientation of ethanol molecules in a bubble surface. More importantly, In terms of solute effects, it appears that while salt anions promote gaseous diffusion, sugar molecules inhibit it.
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Article title: Controlling the Absorption Spectra of Gold Nanoparticles Synthesized via Green Synthesis Using Brown Seaweed (Sargassum crassifolium) Extract
Authors: Johnny Jim S. Ouano, Mar Christian O. Que, Blessie A. Basilia and Arnold C. Alguno
Publication title: Key Engineering Materials 772:78-82, July 2018

Abstract:
Gold nanoparticles were synthesized using brown seaweed ( Sargassum crassifolium ) extract and chloroauric acid solution. This is an easy, cheap and environment friendly synthesis method for the formation of gold nanoparticles. The gold nanoparticles with varying amount of seaweed extract was characterized using Ultraviolet-visible spectroscopy. Moreover, Transmission Electron Microscopy characterization was used to observe the shape and size of gold nanoparticles. Experimental results revealed that varying the amount of brown seaweed extract can control the optical absorption spectra of the produced gold nanoparticles. Greater amount of brown seaweed extract will exhibit peak in the lower wavelength while smaller amount of seaweed extract will exhibit peak in the higher wavelength. It is believed that the wavelength of free surface electrons resonance is related to the shift of absorption peak. TEM images revealed a more spherical and smaller particles as the amount of brown seaweed extract was increased. This simple green synthesis method of gold nanoparticles will give a cost effective route in the mass production of gold nanoparticles for biomedical applications.
Full text link https://tinyurl.com/2p8ajt94

Article title: Controlling the Absorption of Gold Nanoparticles via Green Synthesis Using Sargassum crassifolium Extract
Authors: Angeline F. Maceda, Johnny Jim S. Ouano, Mar Christian O. Que, Blessie A. Basilia, Melchor J. Potestas, Arnold C. Alguno
Publication title: Key Engineering Materials 765:44-48, March 2018

Abstract:
This work controls the absorption of gold nanoparticles (GNPs) via green synthesis utilizing Sargassumcrassifolium extract. The amount of seaweed extract acts as both reducing (from Au ⁺ to Au ⁰ ) and capping agent. The S.crassifolium extract is mainly composed of biomolecules such as protein and phenolic compounds which are responsible for the synthesis of GNPs. The synthesized GNPs were characterized using UV-Visible spectroscopy, Fourier Transform Infrared (FTIR) spectroscopy and Transmission Electron Microscopy (TEM). UV-Vis spectra revealed peaks around 505 nm to 544 nm which corresponds to the Surface Plasmon Resonance (SPR) of GNPs. FTIR spectroscopy analysis showed peak at 825 cm ⁻¹ and 1144 cm ⁻¹ which corresponds to the signature peaks of GNPs. Polydisperse GNPs with varied sizes (between 5 nm to 300 nm) were further confirmed by TEM analysis.
Full text link https://tinyurl.com/37u3hhf5

Article title: Synthesis and Characterization of Polysulfone (PSU)/Philippine Halloysite (PH-HAL) Nanostructured Membrane via Electrospinning
Authors: Ruth R. Aquino, Marvin S. Tolentino, Niel Karl G. Arcamo, John Patrick N. Gara1, and Blessie A. Basilia
Publication title: MATEC Web of Conferences 213(7-8):03001, January 2018

Abstract:
Membrane technology is widely used in many separation processes because of its multi-disciplinary characteristics. One of the techniques that is used in the fabrication of membranes is the electrospinning process which can create nanofibers from a very wide range of polymeric materials. In this study, electrospun nanostructured fibrous composite membranes of polysulfone (PSU), commercial halloysite (COM-HAL), and Philippine halloysite (PH-HAL) were synthesized. The concentrations of COM-HAL and PH-HAL were both varied from 0.5%, 1%, and 2%. The FTIR results showed that there were changes in the intensity of the PSU-IR spectra which confirmed the presence of COM-HAL and PH-HAL in the synthesized membranes. The SEM revealed that nanofibers can be successfully produced by the addition of LiCl salt in PSU with varying HAL concentrations. Also, it was observed that the addition of HAL with varying concentrations have no significant effect on wettability due to the strong hydrophobic character of the PSU membrane. Moreover, it was found from the analysis of mechanical properties that the tensile strength of the membranes weakened by the addition of HAL due to its weak interaction with PSU.
Full text link https://tinyurl.com/2p95dk74

Article title: Facile Synthesis of Nitrogen-doped Carbon Quantum Dots for Bio-imaging
Authors: Persia Ada N. de Yro, Beejay T. Salon , Blessie A. Basilia , Mark Daniel de Luna and Peerasak Paopraser
Publication title: MATEC Web of Conferences 43:04002, January 2016

Abstract:
Carbon quantum dots (CQD) with fascinating properties has gradually become a rising star as a new nanocarbon member due to its nonthreatening, abundant and inexpensive nature. This study reports on a facile preparation of fluorescent carbon quantum dots (CQD) from iota Carrageenan. CQD from iota Carrageenan was produced by hydrothermal method with a quantum yield (QY) of 16 to 20%. Doping the CQD with nitrogen by the addition of tetraethylene pentamine (TEPE) produced CQD with a QY of 77%. FTIR data confirmed the formation of hydroxyl, carboxylic and carbonyl functional groups as confirmed by the ToFSIMS data due to the presence of nitrogen bonds on the N-CQD produced with TEPE. The CQD and N-CQD produced are crystalline with graphitic structures because of the presence of sp2 graphitic d line spacing with the sizes ranging from 2 to 10nm. To examine the feasibility of using the CQD as nanoprobe in practical applications, labelling and detection of E.coli was performed. The E.coli fluoresced proving CQD as an effective probe in bio imaging application. This study has successfully demonstrated a facile approach of producing CQD with significant high quantum yields to fluorescent CQD for bio imaging applications.
Full text link https://tinyurl.com/tn6vden5

Article title: Ethylenediamine and ethylene glycol stabilized colloidal PbX (X=S, Se, Te) nanocrystals via amide- and ester-derivatives of 1-(propanoic acid)-3-methylimidazolium bromide ionic liquid
Authors: Anna Zarina Ladaga, Katrina Veia Manalang, Irwin Romero, Jo Ann Sya, Ian Harvey Arellano, Blessie Basilia
Publication title: Materials Letters 136:420-423, December 2014

Abstract:
The stability of colloidal nanocrystals in common solvents such as water is paramount in the processibility and practical application of these materials in industrial scale. Herein, we show that a bifunctional ionic liquid (IL) 1-(propanoic acid)-3-methylimidazolium bromide is an effective capping agent in the solvothermal synthesis of water-stable colloidal lead chalcogenide, PbX (X=S, Se, Te), nanocrystals. IL-capped PbX were produced using ethylenediamine (ED) and ethylene glycol (EG) as solvents. The addition of EG or ED in water at 50% (v/v) produced higher quality nanocrystals compared with nanocrystals produced in pure water, EG or ED. This enhancement originated from direct stabilization from the in situ formation of amide- and ester-derivatives of the IL in aqueous ED and EG, respectively.
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Article title: Plasma-treated Abaca Fabric/Unsaturated Polyester Composite Fabricated by Vacuum-assisted Resin Transfer Molding
Authors: Marissa A. Paglicawan, Byung Sun Kim, Blessie A. Basilia1, Carlo S. Emolaga, Delmar D. Marasigan, and Paul Eric C. Maglalang
Publication title: International Journal of Precision Engineering and Manufacturing-Green Technology 1(3):241-246, June 2014

Abstract:
To improve the adhesion and wetting between the abaca fibers and matrix, the surface of abaca fabric was modified using plasma polymerization. Different plasma exposure times were conducted to determine the effect of plasma treatment on the properties of the composites. A combination of plasma and other surface modification processes was also investigated to determine whether double treatments could further enhance the properties of these composites. Combined treatments involve plasma polymerization of the fabric after pretreatment with one of the following surface-modification reagents: a) γmethacrylopropyltrimethylsilane, b) triethoxyvinylsilane, and c) 2%w/w NaOH (aq).The abaca fabric/unsaturated polyester composites were fabricated using the vacuumassisted resin transfer molding (VARTM) technique.SEM results showed that 10 to 20 seconds plasma treatment gave the right amount of surface roughness for maximum fiber and matrix adhesion leading to improved mechanical properties of the composites. Longer plasma treatment time and double treatment however resulted in composites with lower mechanical properties. Although the composite with alkali and plasma-treated fabric showed the lowest mechanical properties it exhibited the lowest water uptake in both distilled water and brine solution.
Full text link https://tinyurl.com/m72ar575

Article title: Facile in situ thermolytic growth of ZnS quantum dots in polystyrene matrix from zinc pyrrolidinedithiocarbamate as single source precursor
Authors: Mar Christian O. Que, Mari Montesa, Jo Ann Sy, Blessie A. Basilia, Ian Harvey J. Arellano
Publication title: Materials Letters 109:186-189, October 2013

Abstract:
Polystyrene (PS) embedded ZnS QDs were prepared via thermolysis of the single source precursor, zinc pyrrolidinedithiocarbamate (ZnPDTC). The in situ growth of 4-6 nm QDs was realized by thermal treatment at 375 degrees C and 475 degrees C at different durations, chosen to represent the rubbery and molten state of the polymer matrix. The morphology of the PS/ZnPDTC nanocomposite film was evaluated using AFM. The growth kinetics was found to be faster at the polymer's molten state compared to its rubbery state.
Full text available upon request to the author

Article title: Water Uptake and Tensile Properties of Plasma Treated Abaca Fiber Reinforced Epoxy Composite
Authors: Marissa A. Paglicawan, Blessie A. Basilia, Byung Sun Kim
Publication title: Composites Research 26(3):165-169, June 2013

Abstract:
This work presents the tensile properties and water uptake behavior of plasma treated abaca fibers reinforced epoxy composites. The composites were prepared by vacuum assisted resin transfer molding. The effects of treatment on tensile properties and sorption characteristics of abaca fiber composites in distilled water and salt solution at room temperature were investigated. The tensile strength of the composites increased with plasma treatment. With plasma treatment, an improvement of 92.9% was obtained in 2.5 min exposure time in plasma. This is attributed to high fiber-matrix compatibility. Less improvement on tensile properties of hybrid treatment of sodium hydroxide and plasma was obtained. However, both treatments reduced overall water uptake in distilled water and salt solution. Hydrophilicity of the fibers decreased upon plasma and sodium hydroxide treatment, which decreases water uptake.
Full text link https://tinyurl.com/4d3hkv64

Article title: Influence of Nanoclay on the Properties of Thermoplastic Starch/Poly(lactic acid) Blends
Authors: Paglicawan, Marissa A.; Basilia, Blessie A.; Navarro, Ma. Teresa V.; Emolaga, Carlo S.
Publication title: Journal of Biobased Materials and Bioenergy 7(1):102-107, February 2013

Abstract:
Thermoplastic starch is a type of biodegradable material based on starch. However, this material has high water solubility and may lose their mechanical properties in humid conditions. To solve this, biodegradable blends were prepared by melt blending of thermoplastic starch (TPS) and synthetic polylactic acid. The thermoplastic starch with different amounts of locally produced nanoclay was prepared by mixing the 70% starch with glycerol and water in a single screw extruder. The blends were composed of TPS nanocomposites andpolylactic acid in the presence of maleic anhydride. The blend ratios of TPS with nanoclay and PLA were 70:30 and 30:70. The mechanical properties of the biodegradable blends, thermal characteristics, structural behavior, microstructures and water resistance were evaluated. The mechanical properties of PLA/TPS nanocomposite with maleic anhydride were higher than the physical blends of PLA/TPS without maleic anhydride and nanoclay. The XRD result showed that the biodegradable blend nanocomposites exhibited the intercalation of nanoclay within the blends matrix. The microstructure of the blends in the presence of maleic anhydride showed homogenous and smoother surface. The crystallization temperature of the biodegradable blends shifted to a lower temperature compared to the physical blend of TPS nanoclay/PLA. The blends showed better water resistance compared to the physical blend of TPS and PLA.
Full text available upon request to the author

Article title: Study of recycled plastic aluminates relative to environmental physical stresses as barrier material
Authors: Delia B. Senoro, Albert A. Grino, Jr., Donamel M. Saiyari and Blessie A. Basilia
Publication title: Sustain. Environ. Res., 22(6), 387-394, January 2012

Abstract:
This study investigated the capability of recycled plastic aluminates (RPAs) against environ-mental stresses. These environmental physical stresses of concern are: water, leachate and gas vapour permeation; thermal conductivity, and environmental stress cracking (ESC). RPAs possess properties potential as environmental protection material. The permeation properties with respect to water, gas, leachate, as well as thermal insulation and ESC, that would aid in concluding that RPAs as a barrier material has not been investigated. Hence, this study was carried out with the objective to investigate the above mentioned properties. Flexible plastic aluminium laminate trimmings (FPALTs) and vari-able weight percentages of organoclay (OC) were formulated, processed, characterized and ex-amined. Methods of examination followed those procedures of American Society for Testing and Materials and International Standards Organization. Fourier Transformed Infrared (FTIR) approach was used for the investigation of ESC resistance. Results showed that impregnation of OC improved the water vapour permeability and thermal insulation property. RPA with 10% OC is the best per-forming RPAs for thermal insulation. All RPAs batches are considered water and leachate vapour barrier, gas vapour retarder, and moderate thermal insulator. FTIR showed that all pristine RPAs, i.e., regardless of thickness and FPALT particle size, are ESC resistant. With the above mentioned results of the study, it was concluded that RPAs are indeed a barrier and moderate insulator material that would have potential economic value for public consumption. However, it is recommended to con-duct further investigation to fully understand the effects of OC concentration in reduced permeability of RPAs. Also, detailed study on economic related analysis and risk assessment is necessary to ensure environmental and public health safety.
Full text link https://tinyurl.com/4yfsnm5z

Article title: Synthesis and characterization of RPET/organo-montmorillonite nanocomposites
Authors: Blessie A. Basilia, Herman D. Mendoza, Dr. Eng. and Leonorina G. Cada, Ph.D.
Publication title: Philippine Engineering Journal (2002) XXII1 (2): 19-34, January 2011

Abstract:
Recycled polyethylene terephthalate (RPET)/organo-montmorillonite nanocomposites were synthesized by direct melt intercalation method. The effect of this processing technique in the nanomorphology, thermal stability and mechanical behavior of the intercalated products were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), small angle x-ray scattering (SAXS), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and mechanical analysis. The difference of using recycled PET (RPET) vis-à-vis virgin PET (VPET) as matrix in the polymer nanocomposites, using synthesized Philippine organo-montmorillonite or commercial organoclay as the layered-silicate, was evaluated. • Results showed that direct melt intercalation by twin-screw extrusion method gave generally exfoliated structures especially at <5% clay loading, based on powder XRD patterns. SAXS patterns and HRTEM micrographs revealed laminated structures at the basal (001) reflections resulting to a d-spacing of 14nm in localized areas not observed by powder diffraction. Higher levels of orientation of the layered silicates were obtained with commercial organoclay compared with the synthesized clay. Thermal degradation has been decreased and tensile strength increased with the increase in clay loading. RPET resin was intercalated in a similar manner with VPET in the layered silicates of Philippine organo-montmorillonite.
Full text link https://tinyurl.com/yf4yt3fk