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Magnetically stabilized fluidized bed reactor (MSFBR) is a sustainable and cost-effective biotechnological process, which justifies the increasing search for biocatalytic superparamagnetic supports to enzyme immobilization. This work, investigates the effect of modified nanomagnetite, Fe3O4 (nM), for biocatalytic support on properties associated with catalytic behavior and potential use in MSFBR. The nM was either synthesized and then modified with 3-aminopropyltriethoxysilano (nM-APTES) or stabilized with oleic acid (nM-OA) and later modified with chitosan (nM-OA-Cs). A novel correlation study was carried out about the support dimension effect, enzymatic surface loading and retained activity. Both nM-based supports were morphologically, structurally and magnetically characterized by X-ray diffraction, thermogravimetry, Mössbauer and Fourier-transform Infrared spectroscopies, as well as vibration sample magnetometry, scanning (SEM) and transmission (TEM) electron microscopies. The nM-APTES and nM-OA samples disclosed crystal sizes of 8.07 and 8.69 nm, respectively. From TEM imagens, the average particles sizes were 10.9 nm for nM-APTES and 12.6 nm for nM-OA. The nM-OA-Cs displayed an average particles size of 918.6 μm. These magnetic supports displayed high saturated magnetization, 79.6 emu/g for nM-APTES and 72.7 emu/g for nM-OA. The amano lipase AK enzyme was immobilized on supports activated with glutaraldehyde. The enzyme loading density of nM-APTES-GA-Lip (122 mg/g) with 61% immobilization yield was higher than that of nM-OA-Cs-GA-Lip (46 mg/g) with 23% immobilization yield. The catalytic activity of nM-APTES-GA-Lip (85%) was higher than that of nM-OA-Cs-GA-Lip (46%), which reflected the correlation between enzyme loading efficiency on the magnetic nanosupports and their relative activity, essential to potential use in MSFBR.
Ellen F. Bôa Morte; Darlan S. Marum; Elisa B. Saitovitch; Mariella Alzamora; Sergio Neves Monteiro; Ruben J. Sanchez Rodriguez. Modified magnetite nanoparticle as biocatalytic support for magnetically stabilized fluidized bed reactors. Journal of Materials Research and Technology 2021, 14, 1112 -1125.
AMA StyleEllen F. Bôa Morte, Darlan S. Marum, Elisa B. Saitovitch, Mariella Alzamora, Sergio Neves Monteiro, Ruben J. Sanchez Rodriguez. Modified magnetite nanoparticle as biocatalytic support for magnetically stabilized fluidized bed reactors. Journal of Materials Research and Technology. 2021; 14 ():1112-1125.
Chicago/Turabian StyleEllen F. Bôa Morte; Darlan S. Marum; Elisa B. Saitovitch; Mariella Alzamora; Sergio Neves Monteiro; Ruben J. Sanchez Rodriguez. 2021. "Modified magnetite nanoparticle as biocatalytic support for magnetically stabilized fluidized bed reactors." Journal of Materials Research and Technology 14, no. : 1112-1125.
Graphene oxide (GO) incorporation in natural fiber composites has recently defined a novel class of materials with enhanced properties for applications, including ballistic armors. In the present work, the performance of a 0.5 vol % GO-incorporated epoxy matrix composite reinforced with 30 vol % fabric made of ramie fibers was investigated by stand-alone ballistic tests against the threat of a 0.22 lead projectile. Composite characterization was also performed by Fourier-transform infrared spectroscopy, thermal analysis and X-ray diffraction. Ballistic tests disclosed an absorbed energy of 130 J, which is higher than those reported for other natural fabrics epoxy composite, 74–97 J, as well as plain Kevlar (synthetic aramid fabric), 100 J, with the same thickness. This is attributed to the improved adhesion between the ramie fabric and the composite matrix due to the GO—incorporated epoxy. The onset of thermal degradation above 300 °C indicates a relatively higher working temperature as compared to common natural fiber polymer composites. DSC peaks show a low amount of heat absorbed or release due to glass transition endothermic (113–121 °C) and volatile release exothermic (~132 °C) events. The 1030 cm−1 prominent FTIR band, associated with GO bands between epoxy chains and graphene oxide groups, suggested an effective distribution of GO throughout the composite matrix. As expected, XRD of the 30 vol % ramie fabric-reinforced GO-incorporated epoxy matrix composite confirmed the displacement of the (0 0 1) peak of GO by 8° due to intercalation of epoxy chains into the spacing between GO layers. By improving the adhesion to the ramie fabric and enhancing the thermal stability of the epoxy matrix, as well as by superior absorption energy from projectile penetration, the GO may contribute to the composite effective ballistic performance.
Artur Camposo Pereira; Andreza Menezes Lima; Luana Cristyne Da Cruz Demosthenes; Michelle Souza Oliveira; Ulisses Oliveira Costa; Wendell Bruno Almeida Bezerra; Sergio Neves Monteiro; Ruben Jesus Sanchez Rodriguez; Janine Feitosa De Deus; Wagner Anacleto Pinheiro. Ballistic Performance of Ramie Fabric Reinforcing Graphene Oxide-Incorporated Epoxy Matrix Composite. Polymers 2020, 12, 2711 .
AMA StyleArtur Camposo Pereira, Andreza Menezes Lima, Luana Cristyne Da Cruz Demosthenes, Michelle Souza Oliveira, Ulisses Oliveira Costa, Wendell Bruno Almeida Bezerra, Sergio Neves Monteiro, Ruben Jesus Sanchez Rodriguez, Janine Feitosa De Deus, Wagner Anacleto Pinheiro. Ballistic Performance of Ramie Fabric Reinforcing Graphene Oxide-Incorporated Epoxy Matrix Composite. Polymers. 2020; 12 (11):2711.
Chicago/Turabian StyleArtur Camposo Pereira; Andreza Menezes Lima; Luana Cristyne Da Cruz Demosthenes; Michelle Souza Oliveira; Ulisses Oliveira Costa; Wendell Bruno Almeida Bezerra; Sergio Neves Monteiro; Ruben Jesus Sanchez Rodriguez; Janine Feitosa De Deus; Wagner Anacleto Pinheiro. 2020. "Ballistic Performance of Ramie Fabric Reinforcing Graphene Oxide-Incorporated Epoxy Matrix Composite." Polymers 12, no. 11: 2711.
Magnetic particles coated with chitosan-based hydrogel were prepared and characterized by infrared spectroscopy, thermal analysis, atomic force microscopy (AFM), energy dispersive X-ray (EDX), wide angle X-ray diffraction (WAXD) and by vibrating sample magnetometry. A polyelectrolyte complex of chitosan (CH) and Sterculia striata gum (CHG) was employed as a coating. FT-IR analysis of the hydrogel obtained revealed the presence of main characteristic bands of CH, CHG and magnetite (Fe3O4). The thermograms showed a moderate efficiency of magnetite incorporation (26.0%) in the hydrogel, as well as evidence of interactions between functional groups of magnetite and biopolymers. Patterns of X-ray diffraction showed the presence of magnetite in the hydrogel with saturation magnetization of 36.5 emu g−1 and crystal average size of 20.8 nm. The hydrogel was found to present a negatively charged outer surface. EDX and AFM revealed that Fe3O4 nanoparticles were aggregated, forming large clusters. The CH /CHG hydrogel was shown to be suitable for magnetite coating, enabling its future application such as a drug carrier and a water remediation agent.
Vanessa De A. Pereira; Irisvan S. Ribeiro; Haroldo C.B. Paula; Regina C.M. de Paula; Rubem Luis Sommer; Ruben Jesus Sanchez Rodriguez; Flavia O.M.S. Abreu. Chitosan-based hydrogel for magnetic particle coating. Reactive and Functional Polymers 2019, 146, 104431 .
AMA StyleVanessa De A. Pereira, Irisvan S. Ribeiro, Haroldo C.B. Paula, Regina C.M. de Paula, Rubem Luis Sommer, Ruben Jesus Sanchez Rodriguez, Flavia O.M.S. Abreu. Chitosan-based hydrogel for magnetic particle coating. Reactive and Functional Polymers. 2019; 146 ():104431.
Chicago/Turabian StyleVanessa De A. Pereira; Irisvan S. Ribeiro; Haroldo C.B. Paula; Regina C.M. de Paula; Rubem Luis Sommer; Ruben Jesus Sanchez Rodriguez; Flavia O.M.S. Abreu. 2019. "Chitosan-based hydrogel for magnetic particle coating." Reactive and Functional Polymers 146, no. : 104431.
Biodegradable materials that combine bioactivity with sustained drug release have been proved promising for the treatment and prophylaxis of bone infection. In this work, injection-molded nanocomposites were formulated from poly(3-hydroxybutyrate-co-3-6%hydroxyvalerate) (PHBV), nanodiamond (nD) and nanohydroxyapatite (nHA) loaded with vancomycin (VC). The components were compounded using a rotary evaporator (PHBV/nHA/VC/nD-R) or a spray-dryer (PHBV/nHA/VC/nD-SD). The nanoparticles acted as a nucleating agent, increasing PHBV crystallinity from 57.1% to up to 73.3% (PHBV/nHA/VC/nD-SD). The nHA particles were found to be well distributed on the formulations fracture surface observed by SEM-EDS micrographs. PHBV/nHA/VC/nD-SD presented higher glass transition temperature (18.1 vs 14.8 °C) and stronger interface than PHBV/nHA/VC/nD-R, as determined by dynamic mechanical analysis (DMA). Furthermore, the incorporation of nanoparticles increased PHBV flexural elastic modulus by 34% and match the reported for human bone. Both systems were able to present a sustained release of VC for 22 days, reaching 7.1 ± 1.3%(PHBV/nHA/VC/nD-R) and 4.8 ± 0.6% (PHBV/nHA/VC/nD-SD). VC presented antibacterial activity even after being processed at 178 °C in an injection molding machine. Moreover, in vitro assays showed a good adhesion and growth of cells on the specimens and suggested a non-cytotoxic and non-cytostatic behavior. These findings indicate that these systems can be further explored as bone defect filling material.
Gabriel Rodrigues De Almeida Neto; Mariana Valinhos Barcelos; Maria Eduarda Araújo Ribeiro; Marcio Manhaes Folly; Ruben Jesus Sanchez Rodriguez. Formulation and characterization of a novel PHBV nanocomposite for bone defect filling and infection treatment. Materials Science and Engineering: C 2019, 104, 110004 .
AMA StyleGabriel Rodrigues De Almeida Neto, Mariana Valinhos Barcelos, Maria Eduarda Araújo Ribeiro, Marcio Manhaes Folly, Ruben Jesus Sanchez Rodriguez. Formulation and characterization of a novel PHBV nanocomposite for bone defect filling and infection treatment. Materials Science and Engineering: C. 2019; 104 ():110004.
Chicago/Turabian StyleGabriel Rodrigues De Almeida Neto; Mariana Valinhos Barcelos; Maria Eduarda Araújo Ribeiro; Marcio Manhaes Folly; Ruben Jesus Sanchez Rodriguez. 2019. "Formulation and characterization of a novel PHBV nanocomposite for bone defect filling and infection treatment." Materials Science and Engineering: C 104, no. : 110004.
Nowadays there is an increasing tendency to reuse industrial residues in order to reduce their environmental impact. A typical alternative for a residue is to be incorporate into a productive process that could be economically viable. In this work, 80 wt% of residues, quarry dust and chamotte from brick industries, were incorporated into 20 wt% of epoxy resin for the production of a novel artificial ornamental stone to be used in civil construction. For preparation of test specimens the granulometric composition associated with the best packaging of residues was determined by the Simplex method. Artificial stone plates were produced using vibration and vacuum processes. Specimens were tested for mechanical, physical and thermal properties as well as chemical resistance. The developed artificial stone presented mechanical properties within the standard expected range, with rupture stress of 30 MPa. Density and thermal behavior were also found to comply with values of natural ornamental stones applied in civil construction. This artificial stone was resistant to chemical attack by HCl, one of the most aggressive acid, which caused a weight loss of only 0.08 g. According to wear test, the thickness reduction indicated that the artificial stone could be used for high traffic pavement.
Maria Luiza P.M. Gomes; Elaine A.S. Carvalho; Larissa N. Sobrinho; Sergio Monteiro; Ruben Jesus Sanchez Rodriguez; Carlos Maurício F. Vieira. Production and characterization of a novel artificial stone using brick residue and quarry dust in epoxy matrix. Journal of Materials Research and Technology 2018, 7, 492 -498.
AMA StyleMaria Luiza P.M. Gomes, Elaine A.S. Carvalho, Larissa N. Sobrinho, Sergio Monteiro, Ruben Jesus Sanchez Rodriguez, Carlos Maurício F. Vieira. Production and characterization of a novel artificial stone using brick residue and quarry dust in epoxy matrix. Journal of Materials Research and Technology. 2018; 7 (4):492-498.
Chicago/Turabian StyleMaria Luiza P.M. Gomes; Elaine A.S. Carvalho; Larissa N. Sobrinho; Sergio Monteiro; Ruben Jesus Sanchez Rodriguez; Carlos Maurício F. Vieira. 2018. "Production and characterization of a novel artificial stone using brick residue and quarry dust in epoxy matrix." Journal of Materials Research and Technology 7, no. 4: 492-498.
One of the major concerns of mining companies is the safety of their tailing dams. Among the cares required to operate such a dam, a proper treatment of the effluent composing its waste stands out, since that, waste must be treated before returned to the environment. In the process of bauxite beneficiation, the effluent level of turbidity is the discard parameter that deserves attention. In this work, quaternized chitosan (TMCCl−) derivative with cationic charge was synthetized and investigated to be used as coagulant in bauxite treatment for tailing dam effluent. The chitosan (CHT) was quaternized by methylation reaction. The quaternized chitosan structure was characterized by the following techniques: FTIR Spectroscopy and 1H nuclear magnetic resonance (NMR). Its thermal stability was analyzed by differential scanning calorimetry (DSC) and thermogravimetric analysis. After quaternized chitosan was obtained, analysis with aluminum sulfate, protonated and quaternized chitosan were executed in jar-test apparatus. The tests were conducted in order to find the optimum pH, velocity gradient, coagulant and alkalizer dosages, as well as coagulation, flocculation and decantation time. The studied coagulants showed good results and reduced the effluent turbidity to levels below determined by legislation. By comparing the coagulants, it was possible to state that quaternized chitosan presented higher reduction of effluent turbidity levels; the tests were performed in the same conditions.
Rodrigo Gonçalves Bigogno; Ruben Jesus Sanchez Rodriguez; Marlon De Freitas Abreu. Quaternized Chitosan for Ecological Treatment of Bauxite Mining Effluents. Journal of Polymers and the Environment 2018, 26, 4169 -4175.
AMA StyleRodrigo Gonçalves Bigogno, Ruben Jesus Sanchez Rodriguez, Marlon De Freitas Abreu. Quaternized Chitosan for Ecological Treatment of Bauxite Mining Effluents. Journal of Polymers and the Environment. 2018; 26 (11):4169-4175.
Chicago/Turabian StyleRodrigo Gonçalves Bigogno; Ruben Jesus Sanchez Rodriguez; Marlon De Freitas Abreu. 2018. "Quaternized Chitosan for Ecological Treatment of Bauxite Mining Effluents." Journal of Polymers and the Environment 26, no. 11: 4169-4175.
The incorporation of calcite marble waste in epoxy resin for the production of artificial stone can represent a technical-economical method and environmentally viable, reducing the amount of discarded residue in the environment, and adding economic value to marble waste and enabling the generation of jobs. The production of natural stone in Brazil recorded an exorbitant amount of waste generated in marble processing. Only 75% of marble taken from the deposits it becomes the finished product the rest is discarded. This study aimed to evaluate the mechanical and physical properties of produced artificial marble based in calcite marble waste and epoxy resin. The vacuum vibro compression was used for production as artificial marble and the specimens were cut according to standart NBR 15845. The results indicated that the artificial stones exhibit physical and mechanical results within the expected range for these kinds of materials. Artificial marble with a maximum flexural strength of 31,8 MPa, maximum compressive strength of 85,2 MPa, water absorption below 0.05% and a satisfactory adhesion between load and resin were obtained for the materials produced with 80% wt marble particles and 20% wt epoxy resin, enabling the development of an alternative material for civil construction applications.
Fernanda Souza Silva; Carlos Eduardo Gomes Ribeiro; Ruben Jesus Sanchez Rodriguez. Physical and Mechanical Characterization of Artificial Stone with Marble Calcite Waste and Epoxy Resin. Materials Research 2017, 21, 1 .
AMA StyleFernanda Souza Silva, Carlos Eduardo Gomes Ribeiro, Ruben Jesus Sanchez Rodriguez. Physical and Mechanical Characterization of Artificial Stone with Marble Calcite Waste and Epoxy Resin. Materials Research. 2017; 21 (1):1.
Chicago/Turabian StyleFernanda Souza Silva; Carlos Eduardo Gomes Ribeiro; Ruben Jesus Sanchez Rodriguez. 2017. "Physical and Mechanical Characterization of Artificial Stone with Marble Calcite Waste and Epoxy Resin." Materials Research 21, no. 1: 1.
Carlos E. Gomes Ribeiro; Rubén J. Sanchez Rodriguez; Eduardo A. de Carvalho. Microstructure and mechanical properties of artificial marble. Construction and Building Materials 2017, 149, 149 -155.
AMA StyleCarlos E. Gomes Ribeiro, Rubén J. Sanchez Rodriguez, Eduardo A. de Carvalho. Microstructure and mechanical properties of artificial marble. Construction and Building Materials. 2017; 149 ():149-155.
Chicago/Turabian StyleCarlos E. Gomes Ribeiro; Rubén J. Sanchez Rodriguez; Eduardo A. de Carvalho. 2017. "Microstructure and mechanical properties of artificial marble." Construction and Building Materials 149, no. : 149-155.
Several studies of biodegradable polymers and copolymers have been carried for different applications in the biomedical area. This current study aims to develop a biocomposite to be used as an orthopedic device, using poly(3-hydroxybutyrate-co-3-hydroxyvalerate) P(HB-HV), a biodegradable copolymer, with 94%HB and 6%HV, as matrix; and nanodiamonds (ND) with primary grains of 4-6nm, as reinforcement. The nanodiamonds were previously encapsulated by P(HB-HV) and specimens were prepared using a hydraulic press and injection molding machine, in order to evaluate which method presents a better performance. Thermal and mechanical analyses were done to compare their behavior. The biocomposite and pure P(HB-HV) samples were analyzed by flexural testing, nanoidentation, DMA, XRD, TGA. The distribution of nanodiamonds on the specimen fracture surface were investigated by SEM. The SEM micrographs allowed us to concluded that the encapsulation of nanodiamonds by P(HB-HV) was successfully performed, promoting a better interface and distribution in the polymeric matrix. The presence of ND in the polymeric matrix decreased the P(HB-HV) crystallinity, inhibiting the crystallite growth. The mechanical properties obtained from flexural test, nanoidentation and DMA of the injection-molded specimens were superior to compression-molded, due to its homogeneous and continuous structure. In vitro analysis was performed to evaluate the samples cytoxicity. Keywords: PHBV; nanodiamonds; biomaterials
Mariana Valinhos Barcelos; Gabriel Rodrigues De Almeida Neto; Fabrício Moreira Almeida; Ruben Jesus Sanchez Rodriguez; José Gregório Cabrera Gomez. Thermo-Mechanical Properties of P(HB-HV) Nanocomposites Reinforced by Nanodiamonds. Materials Research 2017, 20, 167 -173.
AMA StyleMariana Valinhos Barcelos, Gabriel Rodrigues De Almeida Neto, Fabrício Moreira Almeida, Ruben Jesus Sanchez Rodriguez, José Gregório Cabrera Gomez. Thermo-Mechanical Properties of P(HB-HV) Nanocomposites Reinforced by Nanodiamonds. Materials Research. 2017; 20 (suppl 2):167-173.
Chicago/Turabian StyleMariana Valinhos Barcelos; Gabriel Rodrigues De Almeida Neto; Fabrício Moreira Almeida; Ruben Jesus Sanchez Rodriguez; José Gregório Cabrera Gomez. 2017. "Thermo-Mechanical Properties of P(HB-HV) Nanocomposites Reinforced by Nanodiamonds." Materials Research 20, no. suppl 2: 167-173.
Ramie ( Boehmeria nivea ) fiber is one of several lignocellulosic fibers with superior strength, but the least investigated, particularly as reinforcement in strong, tough polymeric composites. This paper presents mechanical properties for polyester reinforced with aligned ramie fibers up to 30% by volume. It was found that adding 30 vol% of ramie fibers increases the flexural strength of polyester about three times (212 ± 12 MPa vs. 63 ± 7 MPa) and tensile strength by a factor of two (89 ± 9 MPa vs. 53 ± 3 MPa). Polyester-ramie fiber composites also displayed a significant improvement in toughness. The impact energy values, as measured by Charpy and Izod impact tests, increased nearly two orders of magnitude for 30 vol% ramie fiber composite as compared to neat polyester. Additionally, fractographic studies revealed reasonable wetting of fibers by the polyester resin, and FTIR analysis confirmed a hydrophilic nature of ramie fibers. In spite of weak adhesion between hydrophilic fibers and hydrophobic matrix, composites of improved strength and toughness were demonstrated in this study. Limited fiber-matrix adhesion was reflected in preferential longitudinal propagation of cracks along the fiber/polyester interfaces, indicating also that most of the fracture area is associated with the fiber surface. Keywords: Ramie fiber; Biofibers; Polyester; Thermal Molding; Flexural Properties; Fracture; Impact Strength; Toughness
Noan Tonini Simonassi; Artur Camposo Pereira; Sergio Neves Monteiro; Frederico Muylaert Margem; Ruben Jesus Sanchez Rodriguez; Janine Feitosa De Deus; Carlos Mauricio Fontes Vieira; Jaroslaw Drelich. Reinforcement of Polyester with Renewable Ramie Fibers. Materials Research 2017, 20, 51 -59.
AMA StyleNoan Tonini Simonassi, Artur Camposo Pereira, Sergio Neves Monteiro, Frederico Muylaert Margem, Ruben Jesus Sanchez Rodriguez, Janine Feitosa De Deus, Carlos Mauricio Fontes Vieira, Jaroslaw Drelich. Reinforcement of Polyester with Renewable Ramie Fibers. Materials Research. 2017; 20 (suppl 2):51-59.
Chicago/Turabian StyleNoan Tonini Simonassi; Artur Camposo Pereira; Sergio Neves Monteiro; Frederico Muylaert Margem; Ruben Jesus Sanchez Rodriguez; Janine Feitosa De Deus; Carlos Mauricio Fontes Vieira; Jaroslaw Drelich. 2017. "Reinforcement of Polyester with Renewable Ramie Fibers." Materials Research 20, no. suppl 2: 51-59.
Biopolymers as polyhydroxyalkanoates (PHA) composed by different co-monomers 3-hydroxybutyrate and 3-hydroxyhexanoate [P(3HB-co-3HHx)] has attracted interest since its properties are similar to low density polyethylene. Burkholderia sacchari produces this copolymer with a very low 3HHx molar fraction, about 2 mol%. B. sacchari mutant (unable to produce polymer) was engineered to host PHA biosynthesis genes (phaPCJ) from Aeromonas sp. In addition, a two-step bioprocess to increase biopolymer production was developed. The combination of these techniques resulted in the production of P(3HB-co-3HHx) with 3HHx content up to 20 mol%. The PHA content was about 78% of dry biomass, resulting in PHA volumetric productivities around 0.45glh. The P(3HB-co-3HHx) containing 20 mol% of 3HHx presented an elongation at brake of 945%, higher than reported before for this PHA composition. Here we have described an approach to increase 3HHx content into the copolymer, allowing the precise control of the 3HHx molar fractions.
Thatiane T. Mendonça; Rafaela R. Tavares; Lucas G. Cespedes; Ruben J. Sánchez-Rodriguez; Jan Schripsema; Marilda K. Taciro; José G.C. Gomez; Luiziana F. Silva. Combining molecular and bioprocess techniques to produce poly(3-hydroxybutyrate- co -3-hydroxyhexanoate) with controlled monomer composition by Burkholderia sacchari. International Journal of Biological Macromolecules 2017, 98, 654 -663.
AMA StyleThatiane T. Mendonça, Rafaela R. Tavares, Lucas G. Cespedes, Ruben J. Sánchez-Rodriguez, Jan Schripsema, Marilda K. Taciro, José G.C. Gomez, Luiziana F. Silva. Combining molecular and bioprocess techniques to produce poly(3-hydroxybutyrate- co -3-hydroxyhexanoate) with controlled monomer composition by Burkholderia sacchari. International Journal of Biological Macromolecules. 2017; 98 ():654-663.
Chicago/Turabian StyleThatiane T. Mendonça; Rafaela R. Tavares; Lucas G. Cespedes; Ruben J. Sánchez-Rodriguez; Jan Schripsema; Marilda K. Taciro; José G.C. Gomez; Luiziana F. Silva. 2017. "Combining molecular and bioprocess techniques to produce poly(3-hydroxybutyrate- co -3-hydroxyhexanoate) with controlled monomer composition by Burkholderia sacchari." International Journal of Biological Macromolecules 98, no. : 654-663.
Studies regarding biodegradable nanocomposites to be used as orthopedics devices have been intensified. This work aims to investigate the influence of ND dispersion on thermal and mechanical properties of a biocomposite of poly(3-hydroxybutyrate) (P(3HB)) reinforced with nanodiamonds (ND) intended to be used as orthopedics devices, with advantages as biodegradability. In order to improve its dispersion, P(3HB) has encapsulated ND in three different mass ratios: P(3HB):ND(16:1), (12:1) and (8:1). However, for all formulations, NDs are presented as agglomerates, in different intensities. In order to relate the distribution of ND within the polymer matrix and biocomposite properties, TGA, DSC, and DMA analysis were done. The formulation with higher content of ND, P(3HB):ND(8:1), presents larger aggregates; thus, decreasing its properties. With smaller and more distributed agglomerates, the 12:1 ratio composite displayed superior storage modulus and glass transition temperature, probably due to better polymer chain restriction.
Gabriel Rodrigues De Almeida Neto; Mariana Valinhos Barcelos; Ruben Jesus Sanchez Rodriguez; José Gregório Cabrera Gomez. Influence of Encapsulated Nanodiamond Dispersion on P(3HB) Biocomposites Properties. Materials Research 2017, 20, 768 -774.
AMA StyleGabriel Rodrigues De Almeida Neto, Mariana Valinhos Barcelos, Ruben Jesus Sanchez Rodriguez, José Gregório Cabrera Gomez. Influence of Encapsulated Nanodiamond Dispersion on P(3HB) Biocomposites Properties. Materials Research. 2017; 20 (3):768-774.
Chicago/Turabian StyleGabriel Rodrigues De Almeida Neto; Mariana Valinhos Barcelos; Ruben Jesus Sanchez Rodriguez; José Gregório Cabrera Gomez. 2017. "Influence of Encapsulated Nanodiamond Dispersion on P(3HB) Biocomposites Properties." Materials Research 20, no. 3: 768-774.
Carlos Maurício F. Vieira; Regina M. Pinheiro; Ruben J. Sanchez Rodriguez; Veronica Scarpini Candido; Sergio N. Monteiro. Clay bricks added with effluent sludge from paper industry: Technical, economical and environmental benefits. Applied Clay Science 2016, 132-133, 753 -759.
AMA StyleCarlos Maurício F. Vieira, Regina M. Pinheiro, Ruben J. Sanchez Rodriguez, Veronica Scarpini Candido, Sergio N. Monteiro. Clay bricks added with effluent sludge from paper industry: Technical, economical and environmental benefits. Applied Clay Science. 2016; 132-133 ():753-759.
Chicago/Turabian StyleCarlos Maurício F. Vieira; Regina M. Pinheiro; Ruben J. Sanchez Rodriguez; Veronica Scarpini Candido; Sergio N. Monteiro. 2016. "Clay bricks added with effluent sludge from paper industry: Technical, economical and environmental benefits." Applied Clay Science 132-133, no. : 753-759.
Alline Sardinha Cordeiro Morais; Carlos Maurício Fontes Vieira; Rubén Jesus Sanchez Rodriguez; Sergio Neves Monteiro; Veronica Scarpini Candido; Carlos Luiz Ferreira. Fluorescent Lamp Glass Waste Incorporation into Clay Ceramic: A Perfect Solution. JOM 2016, 68, 2425 -2434.
AMA StyleAlline Sardinha Cordeiro Morais, Carlos Maurício Fontes Vieira, Rubén Jesus Sanchez Rodriguez, Sergio Neves Monteiro, Veronica Scarpini Candido, Carlos Luiz Ferreira. Fluorescent Lamp Glass Waste Incorporation into Clay Ceramic: A Perfect Solution. JOM. 2016; 68 (9):2425-2434.
Chicago/Turabian StyleAlline Sardinha Cordeiro Morais; Carlos Maurício Fontes Vieira; Rubén Jesus Sanchez Rodriguez; Sergio Neves Monteiro; Veronica Scarpini Candido; Carlos Luiz Ferreira. 2016. "Fluorescent Lamp Glass Waste Incorporation into Clay Ceramic: A Perfect Solution." JOM 68, no. 9: 2425-2434.
Blends of cellulose acetate (CA) and poly(3-hydroxybutyrate) (PHB) were prepared by the solvent-casting method in both the presence and the absence of a compatibilizer agent. The compatibilizer was synthesized by reactive processing between CA and PHB. From the differential scanning calorimetric analysis, it has been identified that CA/PHB blends are immiscible in the range of PHB content studied. The existence of interactions between the components was observed due to the displacement of glass transition temperature relative to PHB phase in the blend. The grafting copolymer promoted the increase of interactions between the phases specifically to compatibilized CA/40%wtPHB blend. This composition shows significant changes in crystalline percentage compared to the uncompatibilized blend. The existence of phase interactions modified the viscoelastic behavior of the compatibilized blends by introducing changes in the chain segment mobility due to the addition of compatibilizer as the dynamic mechanical analysis has pointed out. It was observed that different of the blends with lower PHB content, CA/40%wtPHB compatibilized blend with same compatibilizer content did not reach PHB saturation. This difference in behavior can be attributed to the fact that the content of compatibilizer agent used was the proper amount to promote both PHB domain size reduction and dispersion. POLYM. ENG. SCI., 2016. © 2016 Society of Plastics Engineers
Djalma Souza; Ruben Jesus Sanchez Rodriguez; Marcelo Gomes Da Silva; Teresa Eligio Castillo; Marcos Lopes Dias. Compatibilization of cellulose acetate/poly(3-hydroxybutyrate) blends by grafting copolymer. Polymer Engineering & Science 2016, 56, 689 -696.
AMA StyleDjalma Souza, Ruben Jesus Sanchez Rodriguez, Marcelo Gomes Da Silva, Teresa Eligio Castillo, Marcos Lopes Dias. Compatibilization of cellulose acetate/poly(3-hydroxybutyrate) blends by grafting copolymer. Polymer Engineering & Science. 2016; 56 (6):689-696.
Chicago/Turabian StyleDjalma Souza; Ruben Jesus Sanchez Rodriguez; Marcelo Gomes Da Silva; Teresa Eligio Castillo; Marcos Lopes Dias. 2016. "Compatibilization of cellulose acetate/poly(3-hydroxybutyrate) blends by grafting copolymer." Polymer Engineering & Science 56, no. 6: 689-696.
The present work is part of an innovation research project aiming to develop artificial stone from industrial wastes. In principle, the project goal is to fabricate artificial stones with improved characteristics to be used as plates for housing and road construction. In this work, the specific industrial residue was an electrostatically precipitated powder obtained from the initial sintering stage of an integrated steelmaking plant. Plates were produce by vacuum vibro-compression of epoxy resin mixed with 80 and 85 wt% of this specific residue. After curing, the plates were characterized for physical parameters and mechanical properties. The microstructural aspect of the finishing surface was analyzed for both novel artificial stones by scanning electron microscopy. The results indicated that the 80% residue incorporated artificial stone is superior to the 85% residue incorporated and markedly stronger than a commercial artificial stone, incorporated with granite residue, with comparable density and water absorption. These characteristics favor the technical substitution of the presently investigated artificial for the commercial stone. In particular, based on wear tests, the residue incorporated artificial stone would be restricted to application as pavement in medium traffic roads.
Elaine Aparecida Santos Carvalho; Vinícius Ribeiro Marques; Ruben Jesus Sanchez Rodriguez; Carlos Eduardo Gomes Ribeiro; Sérgio Neves Monteiro; Carlos Maurício Fontes Vieira. Development of Epoxy Matrix Artificial Stone Incorporated with Sintering Residue from Steelmaking Industry. Materials Research 2015, 18, 235 -239.
AMA StyleElaine Aparecida Santos Carvalho, Vinícius Ribeiro Marques, Ruben Jesus Sanchez Rodriguez, Carlos Eduardo Gomes Ribeiro, Sérgio Neves Monteiro, Carlos Maurício Fontes Vieira. Development of Epoxy Matrix Artificial Stone Incorporated with Sintering Residue from Steelmaking Industry. Materials Research. 2015; 18 (suppl 2):235-239.
Chicago/Turabian StyleElaine Aparecida Santos Carvalho; Vinícius Ribeiro Marques; Ruben Jesus Sanchez Rodriguez; Carlos Eduardo Gomes Ribeiro; Sérgio Neves Monteiro; Carlos Maurício Fontes Vieira. 2015. "Development of Epoxy Matrix Artificial Stone Incorporated with Sintering Residue from Steelmaking Industry." Materials Research 18, no. suppl 2: 235-239.
Compact artificial stones are widely used in buildings around the world, and the expected demand to the next years is increasing. In this study, stone fragments from marble processing are recycled as raw materials for produce compact artificial stones using compaction in a vacuum environment (100 mm Hg). Crushed marble waste (80 and 85%wt) are mixed with unsaturated polyester resin as binder. Materials were processed under compaction pressures of 1 and 10 MPa, for 20 minutes at 90 °C. Artificial marble with flexural ultimate strength of 25 MPa, water absorption below 0.2% and homogeneous particles distribution were obtained to materials produced with 80%wt of marble particles. To artificial marbles with 85%wt of particles, lower flexural ultimate strength and higher water absorption were observed (18 MPa and 0.4% respectively). In addition, the greater compaction pressure used improves slightly values obtained in 3 points bending test. Furthermore, tangent delta peaks at 115 °C were observed to evaluated artificial marbles.
Carlos Eduardo Gomes Ribeiro; Ruben Jesus Sanchez Rodriguez. Influence of Compaction Pressure and Particle Content on Thermal and Mechanical Behavior of Artificial Marbles with Marble Waste and Unsaturated Polyester. Materials Research 2015, 18, 283 -290.
AMA StyleCarlos Eduardo Gomes Ribeiro, Ruben Jesus Sanchez Rodriguez. Influence of Compaction Pressure and Particle Content on Thermal and Mechanical Behavior of Artificial Marbles with Marble Waste and Unsaturated Polyester. Materials Research. 2015; 18 (suppl 2):283-290.
Chicago/Turabian StyleCarlos Eduardo Gomes Ribeiro; Ruben Jesus Sanchez Rodriguez. 2015. "Influence of Compaction Pressure and Particle Content on Thermal and Mechanical Behavior of Artificial Marbles with Marble Waste and Unsaturated Polyester." Materials Research 18, no. suppl 2: 283-290.
This paper reports on a study of the influence of sodium alginate concentration and iron addition on the ion exchange kinetics of calcium alginate ferrogel beads produced by external gelation. The calcium absorption and sodium release of the beads were fitted to Fick's second law for unsteady state diffusion in order to obtain the effective diffusion coefficients of Na(+) and Ca(2+). The dried beads were characterized concerning their thermal stability, particle size distribution and morphology. The gelation kinetics showed that an increase in alginate concentration from 1% to 2% increased the Ca(2+) equilibrium concentration, but presented no effect on Ca(2+) effective diffusion coefficient. Alginate concentration higher than 2% promoted saturation of binding sites at the bead surfaces. The addition of iron promoted faster diffusion of Ca(2+) inside the gel beads and reduced the Ca(2+) equilibrium concentration. Also, iron particles entrapped in the alginate gel beads promoted greater absorption of water compared to pure alginate gel and lower thermal stability of the beads. The main diffusion of Ca(2+) into and Na(+) out from the bead took place during the first 60 min, during which almost 85-90% of the Ca(2+) equilibrium concentration is achieved, indicating that this period is sufficient to produce a Ca-alginate bead with high crosslinking of the polymer network.
Vânea Ferreira Torres Teixeira; Nádia Rosa Pereira; Walter Ruggeri Waldman; Ana Luiza Cassiano Dias Ávila; Victor Haber Pérez; Ruben Jesus Sanchez Rodriguez. Ion exchange kinetics of magnetic alginate ferrogel beads produced by external gelation. Carbohydrate Polymers 2014, 111, 198 -205.
AMA StyleVânea Ferreira Torres Teixeira, Nádia Rosa Pereira, Walter Ruggeri Waldman, Ana Luiza Cassiano Dias Ávila, Victor Haber Pérez, Ruben Jesus Sanchez Rodriguez. Ion exchange kinetics of magnetic alginate ferrogel beads produced by external gelation. Carbohydrate Polymers. 2014; 111 ():198-205.
Chicago/Turabian StyleVânea Ferreira Torres Teixeira; Nádia Rosa Pereira; Walter Ruggeri Waldman; Ana Luiza Cassiano Dias Ávila; Victor Haber Pérez; Ruben Jesus Sanchez Rodriguez. 2014. "Ion exchange kinetics of magnetic alginate ferrogel beads produced by external gelation." Carbohydrate Polymers 111, no. : 198-205.
Polymer composites reinforced with natural fiber that were obtained as industrial wastes, are of particular interest due to both the environmental benefits and economical advantages. In the present work sugarcane bagasse fibers, obtained as a waste from sugar and ethanol production, were incorporated in an amount of 25wt% into a polypropylene matrix. These fibers were previously alkali treated with NaOH to improve their adherence to the composite matrix. Thermal analyses were conducted in both types of composites, with untreated fibers and with alkali treated fiber. The result indicated that the alkali treatment improves the compatibility between the bagasse fiber and the polypropylene matrix, which then provides more thermal resistance.
Paula Gomes De Paula; Ruben Jesus Sanchez Rodriguez; Luís Philipe Rangel Duarte; Verônica Scarpini Cândido; Sérgio Neves Monteiro. Formulation and Characterization of Polypropylene Composites Alkali Treated Bagasse Fiber. Materials Science Forum 2014, 775-776, 319 -324.
AMA StylePaula Gomes De Paula, Ruben Jesus Sanchez Rodriguez, Luís Philipe Rangel Duarte, Verônica Scarpini Cândido, Sérgio Neves Monteiro. Formulation and Characterization of Polypropylene Composites Alkali Treated Bagasse Fiber. Materials Science Forum. 2014; 775-776 ():319-324.
Chicago/Turabian StylePaula Gomes De Paula; Ruben Jesus Sanchez Rodriguez; Luís Philipe Rangel Duarte; Verônica Scarpini Cândido; Sérgio Neves Monteiro. 2014. "Formulation and Characterization of Polypropylene Composites Alkali Treated Bagasse Fiber." Materials Science Forum 775-776, no. : 319-324.
Modified montmorilonite additivated films of poly 3 (hydroxybutyrateco-8%-hydroxyvalerate) were formulated by solvent evaporation technique and then characterized by means of X-ray diffraction, scanning electron microscopy, atomic force microscopy and scanning differential calorimetry. A preliminary characterization using these analyses revealed the formation of nanocomposites with partially exfoliated and interlayered structures. These nanocamposites display changes in the crystalline structure of the precursor biodegradable polymer.
Emilene Rita Pimental Da Silva; Ruben Jesus Sanchez Rodriguez; Flávio Costa Miguens; Djalma Souza; Sérgio Neves Monteiro; Verônica Scarpini Cândido. Nanocomposites Obtained by Montmorilonite Clay Additivation in P3 (HB-8%HV). Materials Science Forum 2014, 775-776, 465 -470.
AMA StyleEmilene Rita Pimental Da Silva, Ruben Jesus Sanchez Rodriguez, Flávio Costa Miguens, Djalma Souza, Sérgio Neves Monteiro, Verônica Scarpini Cândido. Nanocomposites Obtained by Montmorilonite Clay Additivation in P3 (HB-8%HV). Materials Science Forum. 2014; 775-776 ():465-470.
Chicago/Turabian StyleEmilene Rita Pimental Da Silva; Ruben Jesus Sanchez Rodriguez; Flávio Costa Miguens; Djalma Souza; Sérgio Neves Monteiro; Verônica Scarpini Cândido. 2014. "Nanocomposites Obtained by Montmorilonite Clay Additivation in P3 (HB-8%HV)." Materials Science Forum 775-776, no. : 465-470.