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The introduction of the high-speed tableting machines and the lack of excipients with good flow and compaction properties required for direct compression process have increased research interest in the development of co-processed excipients. Melt granulation, as an environmentally friendly and cost-effective method, has recently been recognized as a promising co-processing technique. The aim of the present study was to prepare lipid-based co-processed excipients by in situ fluidized bed melt granulation and to investigated their suitability for direct compression process. Lactose monohydrate was co-processed with glyceryl dibehenate (Compritol® 888 ATO) or glyceryl palmitostearate (Precirol® ATO 5), as lipophilic meltable binders. Besides the flowability testing, dynamic compaction analysis was applied for thorough investigation into the tableting properties of developed co-processed excipients. Solid state characterization, performed by means of XRPD and DRIFT, confirmed the absence of chemical changes of the single components of co-processed excipients. Co-processed excipients showed improved flowability in comparison with single ingredients and corresponding physical mixtures. Novel co-processed excipients were found to have better tabletability profiles than physical mixtures of the ingredients, and were able to retain acceptable tensile strength values at high content of paracetamol in tableting mixture. Tablets with high tensile strength could be obtained with less work of compression needed in comparison with the commercial lactose-based excipients. Furthermore, novel lipid-based co-processed excipients were found to be highly superior regarding the antiadhesive and lubricating properties, with no additional lubricants required.

Different surface treatments including mercerization, stearic acid and growth of zinc oxide nanorods as well as their combinations were exploited to address their effects on the properties of green composites based on polylactic acid (PLA) and flax fabrics. The resulting fabrics were morphologically (SEM), crystallographically (XRD) and thermally (TGA) characterized, showing no significant changes with respect to the untreated samples. In contrast, tensile and flexural properties of composites produced by compression moulding were significantly influenced. A combination of mercerization and environmentally friendly stearic acid treatment turned the character of the flax fabric from hydrophilic to hydrophobic, and led to improved bending and tensile strengths by 20% and 12%, respectively, compared to untreated composites. The presence of ZnO nanorods promoted an increase in flexural and tensile stiffness by 58% and 31%, respectively, but at the expense of strength, with reductions ascribed to the degradation of polylactic acid under high-temperature conditions favoured by ZnO, as confirmed by a reduction in the initial thermal degradation temperature up to 26%. These latter composites can be suggested in those applications where a suitable combination of flexural properties and a shorter persistence in the environment is desired.

The effects of butylpyridinium bromide-based ionic liquids (ILs) on the vulcanization kinetics, mechanical properties and photo-actuation ability of styrene-butadiene rubber (SBR) composites filled with graphene nanoplatelets (GnPs) were investigated. Two different ILs, 1-butylpyridinium bromide (BBP) and 4-methyl-1-butylpyridinium bromide (BMBP), were introduced into rubber compounds. The methodology of IL incorporation into the rubber compounds was studied as well. The ILs were added either directly as a single component or after immobilization onto the GnPs surface. High values of the modulus and tensile strength, which are important mechanical properties, were observed for the composites filled with immobilized BMBP. Freely dispersed BBP resulted in composites with the fastest scorch time, highest thermal and electrical conductivity, and best photo-actuation response of 0.230 mm. © 2020 The Authors, Ministry of Education, Youth and Sports of the Czech republic - DKRVO [RP/CPS/2020/003]; National Science Centre, Poland through POLONEZ project [UMO-2016/23/P/ST5/02131]; European Unions's Horizon 2020 research and innovation program under Marie Sklodowska -Curie [665778]; Qatar University [QUCGCAM-19/20-2]

A biorefinery process was set up to simultaneously produce cellulose nanocrystals (CNCs) and an inorganic-organic material composed by silica and lignin starting from rice husk, a largely available agricultural side product. The opportunity to synthesize this new material, combining lignin and silica at the microscopic level, ensued naturally as the two substances were extracted simultaneously during the process. The main parameters influencing the yield, the composition, and the properties of the lignin-silica material (LSM) were optimized. The overall yield of the process was 35% (12% CNCs and 23% LSM). The sub-micrometric irregular particles constituting the LSM were approximately equally composed by lignin and silica. Larger batches were produced to assess the possibility to use the LSM as a reinforcing biofiller in elastomeric composites based on natural rubber. The lignin-silica material reinforced natural rubber (Ultimate elongation +17%, ultimate strength +198%). The overall effect was rationalized in terms of individual contributions of the two constituents: silica was supposed to contribute largely to the reinforcement, whereas lignin seemed to protect natural rubber from degradation, conveniently enhancing the elongation at break and lowering the total density of the biofiller.

Made available in DSpace on 2018-11-26T17:54:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-10-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Ministry of Science, Technology, and Innovation (MCTI/SISNANO) The ever-growing environmental concern arising from the unrestricted exploitation of fossil sources for the massive production of non-biodegradable materials encourages research on alternative renewable resources. We herein pave the route for the production of biodegradable biocomposites made up of carrot minimal processing waste (CMPW) by optimizing its combination with hydroxypropyl methylcellulose (HPMC) and high-pressure microfluidized cellulose fibers, which played ligand and mechanical reinforcement roles, respectively. Ternary mixture designs established mathematical models aimed at structure-composition-property correlations, allowing their mechanical performances to be innovatively predicted without the need for further experiments. The optimized formulation comprised 33 wt.% CPMW and led to biodegradable biocomposites featuring ca. 30 MPa of tensile strength, ca. 3% elongation at break, and ca. 2 GPa of Young's modulus, properties which are suitable for food packaging applications. Finally, the film-forming protocol was successfully scaled-up through a continuous casting approach, allowing the production of 1.56 m(2) of biodegradable biocomposite in each hour. While scaling up did not affect film's barrier to moisture, it did impair its mechanical behavior. Embrapa Instrumentat, LNNA, Rua 15 Novembro,1452, BR-13560979 Sao Carlos, SP, Brazil Univ Fed Sao Carlos, Dept Mat Engn, PPG CEM, Rod Washington Luis,Km 235, BR-13565905 Sao Carlos, SP, Brazil Embrapa Trop Agroind, Rua Dra Sara Mesquita 2270, BR-60511110 Fortaleza, Ceara, Brazil Sao Paulo State Univ, FEIS, Dept Chem & Phys, Ave Brasil 56, BR-15385000 Ilha Solteira, SP, Brazil Sao Paulo State Univ, FEIS, Dept Chem & Phys, Ave Brasil 56, BR-15385000 Ilha Solteira, SP, Brazil FAPESP: 2013/14366-7 FAPESP: 2014/23098-9 CNPq: 303796/2014-6 Ministry of Science, Technology, and Innovation (MCTI/SISNANO): 402287/2013-4

Hydrogen embrittlement behaviors of a high-Mn TWIP (twinning induced plasticity) steel with various grain sizes from coarse grains to ultra-fine grains were studied by hydrogen pre-charging and subsequent slow stain rate tensile tests. The results of the tensile tests showed that the yield strength and tensile strength were not influenced by hydrogen-charging, whereas the total elongation reduced with hydrogen-charging in coarse-grained specimen but no change in the ultrafine-grained specimen. Fracture surfaces showed dimple patterns in all specimens. The present results suggested that the grain refinement suppressed hydrogen embrittlement in the high-Mn TWIP steel, even though the diffusible hydrogen content increased by grain refinement.

This work was aimed at defining models to explain tensile properties of thermoplastic films derived from common wheat flours as a function of source flours characteristics. A total of 26 flours, two blends from an industrial mill and 24 single-cultivar flours collected over three different years of grain production (from 2013 to 2015) and cultivar grain hardness (from soft to hard) were used in a wide range of protein content (from 9.0 to 16.2%) and values of Chopin's alveograph parameters (as indexes of gluten characteristics), i.e., P (from 27 to 160 mm), L (from 32 to 236 mm), P / L (from 0.13 to 4.44), and W (from 63 to 398). The same plasticization recipe and filming procedure was adopted for all manufactures. The maximum tensile strength ( σ max ) and the elongation at break ( e max ), as well as the elastic modulus ( E ), stiffness ( k ) and energy at break ( w b ) of films from flours having moderate to high values of P (>60 mm), P / L (≥0.43) and W (>170) were positively correlated to P and negatively correlated to P / L and W , with all the variables significant ( p -value R 2 = 0.72 for σ max , 0.62 for e max , 0.81 for E , 0.83 for k and 0.72 for w b . The e max of films obtained from flours having moderate to low values of P (≤45 mm), P / L (≤0.42) and W (≤160) was negatively correlated to P , L and P / L , and positively correlated with W , with all the variables significant ( p -value R 2 = 0.86. On the contrary, no relationship was found for the σ max , as well as for E , k and w b of these films. Results encourage further research aimed at improving the robustness and reliability of models so that tensile properties of a thermoplastic film can be predicted for any given source flour.

To study the interaction of hydrogen and surface structure of iron, two types of tensile test are carried out under hydrogen gas environment and cathodic hydrogen charging condition. According to the tensile tests, hydrogen induces reduction of flow stress (softening) for the specimens without deformed surface, but increase of flow stress (hardening) for the one with deformed surface. The results of jump tests signify that hydrogen enhances the dislocation mobility by reducing the thermal activation volume for overcoming barriers, and because of this, in the samples with smooth surface, homogeneously distributed hydrogen leads to the softening effect. On the other hand, the deformed layer just under the surface has larger solubility of H due to trap sites provided by dislocation cell structures. As a result of hydrogen shielding effect, the strong interaction between dislocations in surface layer and multiplication of new defects causes the hardening effect.

Molecular mobility has long been established to relate to textural properties and stability of polymer films and is therefore an important property to characterise to better understand pharmaceutical film formulations. The molecular mobility of solvent cast hydroxyethyl cellulose (HEC) films has been investigated by means of thermally stimulated current (TSC) below the temperature at which the film was formed. Preliminary physical characterisation of the films was performed using XRPD, TGA, DSC and texture analysis (tensile properties). XRPD results showed the films to be completely amorphous with Tg determined by DSC to be 127 ± 1 °C. TGA analysis showed the films to contain 8 ± 1% water and film was dried to only 0.06 ± 0.01% water content when heated to 160 °C. Application of TSC detected molecular mobility in HEC films at sub-zero temperatures. Two motional transitions with average relaxation time of 50 ± 3 s were identified; a β-relaxation at −57 ± 2 °C, attributed to localised non-cooperative orientation of HEC polymer chain ends and the hydroxyethyl side groups and an α-relaxation, originating from cooperative segmental mobility, at −20 ± 2 °C. The tensile properties i.e., elongation, tensile strength and elastic modulus of the HEC film have been related to the molecular relaxation processes detected by TSC.

Made available in DSpace on 2018-11-26T16:17:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2016-01-01 FINEP/MCT Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Non-biodegradable food packaging materials have caused serious environmental problems due to their inappropriate discard. Biodegradable and renewable polymers (e.g., polysaccharides), when reinforced with nanostructures, have been used to produce novel, eco-friendly food packaging as alternatives to replace conventional packaging. This study aimed at adding chitosan nanoparticles (CSNPs) to high-(HDM) and low-methyl (LDM) pectin matrices to produce HDM pectin/CSNP and LDM pectin/CSNP nanocomposite films, as well as at evaluating the effect of CSNPs on films' mechanical, thermal, and barrier properties. Also, CSNPs were characterized as to zeta potential, average diameter, and FT-IR, whereas nanocomposites' thickness, appearance, structure, morphology, mechanical, thermal, and barrier properties were analyzed. CSNPs presented average diameter and zeta potential near to 110 nm and 50 mV, respectively. The addition of CSNPs improved the mechanical properties, being tensile strength the most affected mechanical attribute (increased from 30.81 to 46.95 MPa and from 26.07 to 58.51 MPa for HDM pectin/CSNP and LDM pectin/CSNP, respectively). These results show that the produced pectin/CSNPs nanocomposites had improved mechanical properties when compared with control pectin films, making these novel materials promising for food packaging production. (C) 2015 Elsevier Ltd. All rights reserved. Univ Fed Sao Carlos, Dept Chem, PPGQ, BR-13566905 Sao Carlos, SP, Brazil Univ Fed Sao Carlos, Dept Mat Engn, PPG CEM, BR-13566905 Sao Carlos, SP, Brazil Sao Paulo State Univ, FEIS, Dept Chem & Phys, BR-15385000 Ilha Solteira, SP, Brazil Embrapa Instrumentacao, LNNA, BR-13560970 Sao Carlos, SP, Brazil Sao Paulo State Univ, FEIS, Dept Chem & Phys, BR-15385000 Ilha Solteira, SP, Brazil CNPq: 402287/2013-4 CNPq: 303.796/2014-6 FAPESP: 2012/24362-6 FAPESP: 2014/23098-9

A diffusion bonding process, for joining of tungsten to ferritic steel using nickel as an interlayer, was developed for nuclear component application. The effect of joining temperature on the microstructure and tensile strength of the joint was investigated in this work. Metallographic analysis revealed that a good bonding was obtained at both the tungsten/nickel and nickel/steel interfaces, and the diffusion products were identified in the diffusion zone. Nano-indentation test across the joining interfaces demonstrated the effect of solid solution hardening in the diffusion zone. Tensile test showed that the maximum average tensile strength of not, vert, similar200 MPa was obtained for the joint diffusion bonded at 900 °C. The results were discussed in terms of the joining temperature and of the residual stress generated during joining process.

This manuscript describes the detailed characterization of edible films made from two different protein products e whey protein isolate (WPI) and whey protein concentrate (WPC), added with three levels of glycerol (Gly) e i.e. 40, 50 and 60%(w/w). The molecular structure, as well as barrier, tensile, thermal,surface and optical properties of said films were determined, in attempts to provide a better understanding of the effects of proteinaceous purity and Gly content of the feedstock. WPI films exhibited statistically lower (p < 0.05) moisture content (MC), film solubility (S), water activity, water vapor permeability (WVP), oxygen and carbon dioxide permeabilities (O2P and CO2P, respectively) and color change values, as well as statistically higher (p < 0.05) density, surface hydrophobicity, mechanical resistance, elasticity, extensibility and transparency values than their WPC counterparts, for the same content of Gly. These results are consistent with data from thermal and FTIR analyses. Furthermore,a significant increase (p < 0.05) was observed in MC, S, WVP, O2P, CO2P, weight loss and extensibility of both protein films when the Gly content increased; whereas a significant decrease (p < 0.05) was observed in thermal features, as well as in mechanical resistance and elasticity e thus leading to weaker films. Therefore, fundamental elucidation was provided on the features of WPI and WPC germane to food packaging e along with suggestions to improve the most critical ones, i.e. extensibility and WVP., Partial funding for this research work was provided by project Milkfilm, administered by Agência de Inovação e POCTI: Programa Operacional de Ciência, Tecnologia e Inovação (Portugal) Funding for author O. L. Ramos was via a postdoctoral fellowship (ref. SFRH/BPD/80766/2011), administered by Fundação para a Ciência e a Tecnologia (Portugal) and supervised by author F. X.Malcata. A minor part of the experimental work was performed in CBQF premises

The development of mixed systems, formed by locustbeangum (LBG), and κ-carrageenan (κ-car) can offer new interesting applications such as the development of ediblefilms with particular properties. κ-car/LBG blend films with different ratios were developed, and their effects on films’ physical properties were assessed. Thermogravimetric analysis (TGA), X-ray diffraction (XRD) patterns, dynamic mechanical analysis (DMA) and Fourier-transform infrared (FTIR) spectroscopy techniques were used to highlight the interactions between the two polysaccharides. The addition of κ-car to LBG improved the barrier properties of the films leading to a decrease of water vapor permeability (WVP). Improved values of elongation-at-break (EB) were registered when the ratio of κ-car/LBG was 80/20 or 40/60 (% w/w). Moreover, the κ-car/LBG blend films enhance the tensile strength (TS) compared to κ-car and LBG films. FTIR results suggested that hydrogen bonds interactions between κ-car and LBG have a great influence in films’ properties e.g. moisture content, WVP. Therefore, different κ-car/LBG ratios can be used to tailor ediblefilms with enhanced barrier and mechanical properties., J.T. Martins, M. A. Cerqueira, A. I. Bourbon and A. C. Pinheiro gratefully acknowledge the Fundacao para a Ciencia e Tecnologia (FCT, Portugal) for their fellowships (SFRH/BD/32566/2006, SFRH/BPD/72753/2010, SFRH/BD/73178/2010 and SFRH/BD/48120/2008, respectively), and B.W.S. Souza acknowledges the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES, Brazil). Prof. Cruz Pinto and Sandra Magina at CICECO-University of Aveiro are gratefully acknowledged for help with the DMA experiments.

Polysulfone/MMT nanocomposite membranes were prepared by a congruence of the wet-phase inversion and the solution dispersion techniques. Different clay contents and two kinds of polysulfone were used in order to investigate the changes in the nanocomposite structure as well as in the thermal and mechanical properties. The increase in the basal spacing with the clay content increase was revealed by SAXRD. TEM images depicted the presence of hybrid morphology and SEM images showed that the clay particles were trapped inside the cross-section pores. By increasing the clay content and polysulfone molar mass, the onset temperature of decomposition was increased and the mass loss was decreased. From DTA studies, it was observed that PSf P-1700 low clay content membranes had higher values of enthalpies and the enthalpy values of PSf P-3500 membranes did not present a regular behavior. Also in the tensile tests, the increase of the clay content up to 4.0 mass% promoted the increase of elongation at break and tensile strength.

Cassava and tree cassava starch films plasticized with glycerol were produced by casting method. Different glycerol contents (30, 35, 40 and 45 wt. % on starch dry basis) were used and the resulting films were fully characterized. Their water barrier and mechanical properties were compared. While increasing glycerol concentration, moisture content, water solubility, water vapour permeability, tensile strength, percent elongation at break and Young's modulus decreased for both cassava and tree cassava films. Tree cassava films presented better values of water vapour permeability, water solubility and percent elongation at break compared to those of cassava films, regardless of the glycerol content.