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The main goal of this study is to improve the mechanical properties of low-alloy steels using an austempering heat treatment that involves combined molten bismuth and gallium (Bi-Ga) alloys. The cooling media is an alternative to the salt media, which is commonly used for austampering heat treatment. The steel was maintained at a constant temperature of 500 °C by immersing it in a cooling medium containing gallium and bismuth. The steel achieved an improvement of 229% in hardness and a 50% increase in tensile strength. Some slight decreases in thermal conductivity and diffusivity occurred as a result of the development of bainite in austempered steel, which affected the thermal behavior of the material. Through the process of bismuth diffusion into the steel grains, phase hardening was improved. To accomplish this, maintaining carbide stability and encouraging uniform carbon distribution were key. 500 °C was the best choice for austempering, where improved mechanical qualities were equally balanced. With its enhanced tensile strength, lightweight applications are now within reach, and the steel's enhanced hardness makes it perfect for uses requiring high durability and resistance to wear. This research emphasizes the potential of molten Bi-Ga austempering to enhance the performance of low-alloy steel across several industrial applications.

The development of transforming Belulang grass (Eleusine indica) fiber into high-value-added products has not been explored. Microcrystalline cellulose (MCC) is a promising natural material that has been widely used in several sectors. This study is focused on the MCC isolation from Belulang grass fibers using alkalization, bleaching, and acid hydrolysis. The effects of these treatments on the chemical composition, surface morphology, crystallinity, and thermal stability of the fibers were evaluated using various techniques. Fourier-transform infrared (FTIR) analysis confirmed the removal of lignin and hemicellulose content through treatments like alkalization and acid hydrolysis. Scanning electron microscopy (SEM) revealed a transformation in the fiber surface from a bundled structure to individual rods with average lengths of 15.64 μm after acid hydrolysis. Acid hydrolysis significantly increased the cellulose content by 119.2 %, while simultaneously reducing hemicellulose and lignin contents by 72.6 % and 84.1 %, respectively. X-ray diffraction (XRD) analysis demonstrated a remarkable increase in crystallinity index from 51.87 % to 75.76 % following hydrolysis. Moreover, thermogravimetric analysis (TGA) confirmed the enhanced thermal stability of MCC, with a decomposition temperature reaching up to 366.53 °C. These findings suggest that MCC derived from Belulang grass has the potential to be a sustainable alternative to synthetic materials for reinforcing biocomposites.

Sansevieria trifasciata fiber (STF) has a high cellulose content and considerable potential as a polymer composite reinforcement. This study aims to investigate the effect of alkali treatment on the physicochemical properties, tensile strength, thermal properties, and surface characteristics of STF. We explored the chemical changes in STF that had undergone alkali treatment and achieved an optimum increase in cellulose content of 51.8 % by weight. Soaking the STF for 120 minutes significantly changed its chemical composition. XRD analysis results indicated an increase in crystallinity index and fiber size by 75 % and 68 nm, respectively. After surface treatment, the density of STF increased to 1225 kg/m3, while the percentage of total weight decreased. Thermogravimetric testing provided relevant data for mechanical and thermal characteristics, including an increase in tensile strength to 535 MPa, a tensile modulus of 4.23 GPa, and thermal stability up to 371 °C. In addition, modification of the fiber surface by alkalization increased the wettability of the matrix, which in turn improved the ability of the fibers to interact with the resin. Observation of fiber morphology showed a reduction in lignin and hemicellulose content, which in turn improved the properties of the resulting composite. These results indicate that STF with optimized surface modification has the potential to be an excellent reinforcement for polymer composites.

Purun fiber (PF), which has been used as a raw material for handicrafts, can be used as a filler in composite materials. The purpose of this study is to determine the characteristics of polyester composites with the addition of PF filler at concentrations (5, 10, and 15 %) with arrangements, namely parallel, random, and woven. In this study, the method used was the press molding method with a size of 20 × 20 × 0.3 cm. The resulting composite was analyzed for functional groups, physical properties, morphological properties, mechanical properties, and thermal properties. The functional group results of PF treatment showed a sharp absorption at wave numbers 1724–2983 cm−1, indicating the presence of C=C vibrations in the aromatic ring. For all fiber arrangements, the addition of 10 % PF resulted in the best composite structure. The results of the highest composite physical properties include density, water absorption, and thickness swelling of 0.958 g/cm−3, 10.079 %, and 24.57 × 10−3, respectively. The results of the highest composite mechanical properties are tensile strength, tensile modulus, elongation, and flexural strength of 813.9519 MPa, 9345.737 MPa, 14.06 MPa, and 58.8399 MPa, respectively. While the results of the thermal properties that can be seen from the percent weight loss of the composite obtained the best results in random samples with a variation of 10 %, the effect of the PF filler ratio on composite heat flow obtained the best results, namely in samples parallel to 5 % with a temperature of 500.87 °C. It can be summarized that PF has the potential as a filler in the manufacture of composites.

Carbon-containing compositions of refractory products with additives of aluminum, silicon, graphite of fractional composition have been developed and optimized, and their technical properties, as well as the phase-mineral composition, have been determined.An experimental setup has been developed to study temperature parameters in given hypothetical layers, calculated heat fluxes and temperature stresses of carbon containing products up to 1300 °C.Temperature stresses and specific heat flows are calculated at the heating rate of the working surface from 4.3 °C/min to 55 °C/min with isothermal exposure of products at 700 °C, 950 °C and 1300 °C.This study is devoted to the technology of obtaining carbon-containing refractories by solid-state combustion method (in SHS mode) with the maximum transformation of low-melting phases into refractory ones using ferroalloy metallurgy waste, as well as to the study of thermophysical properties, composition, and influence of specific heat fluxes on temperature stresses in conditional hypothetical layers obtained carbon-containing SHS refractory products.

The influence of functionalised graphene nanoplatelets with melamine on the thermal and mechanical properties of a 3D-printed photopolymerisable resin is investigated. In this work, a liquid-based 3D printer and stereolithography were employed to fabricate the 3D-printed parts, and a commercial dimethacrylate-based resin was used. The 3D-printed parts were subjected to ultraviolet and thermal post-curing stages to improve thermal and mechanical behaviour. The quality of the graphene nanoplatelets’ functionalisation was characterised by Fourier transform infrared spectroscopy and thermogravimetric analysis. Thermal and mechanical characterisations were performed via thermogravimetric, tensile, and Izod impact tests. The fractured surfaces were observed via scanning electron microscopy. The degree of graphene nanoplatelet dispersion in the polymer matrix is enhanced by bonding with melamine via π–π interactions and inhibited surface defect formation. Results show property enhancements of up to 35% in tensile strength, 78% in impact strength, and 38% in residual weight at 400 °C.

• Tannic acid is neither a good flame retardant nor a highly swelling material. • TA combined with CLS reduces flammability of biocomposite by 30 % compared to PLA. • Mixing of TA with CLS in melt doesn't allow for PHRR reduction of more than 20 %. The purpose of this study was to determine the quantitative and qualitative effects of the form of natural phenolic compounds (NPCs) on the decomposition of polylactide (PLA) under different measurement conditions. For this purpose, thermogravimetry analysis (TGA), differential scanning calorimetry (DSC), and pyrolysis-combustion flow calorimetry (PCFC) analyses were carried out not only on individual raw materials like calcium lignosulfonate (BX), tannic acid (TA), BX chemically modified with TA (BMT), but also on PLA/BX, PLA/TA, and PLA/BMT composites with 3, 6, and 9 wt.% of filler. Moreover, the work checked whether to obtain satisfactory results it is necessary to carry out chemical modification lasting many hours, or whether simple physical mixing of ingredients (TABX) is enough, e.g. in proportions 1:2, 2:4, 3:6. The results of these analyses showed that TA is neither a good flame retardant nor a highly swelling material, but when combined with BX physically or chemically, it can produce an interesting synergistic effect. This work proves that chemically obtained BMT hybrid material allows to reduce flammability by 30 % compared to PLA which cannot be achieved by physically mixing these components in a polymer melt. On the other hand, the addition of TABX is sufficient to achieve a good thermal stabilization effect under processing conditions. [Display omitted] [ABSTRACT FROM AUTHOR]

The effects of substituting the B cation in A3BO7 ceramics on their thermal physical properties were investigated by applying a large mass difference. Y3(Nb1‐xTax)O7 (x = 0, 0.1, 0.2, 0.3, 0.4, and 0.5) ceramics were synthesized, and their structural characteristics were determined. All the fabricated Y3(Nb1‐xTax)O7 ceramics showed defective fluorite structures and glass‐like low thermal conductivity (1.18−2.04 W/m∙K at 25°C) because of the highly distorted crystal structure and significant mass difference. Substitution with Ta5+ enhanced the sintering resistance, leading to superior thermal‐insulating performance via grain boundary scattering. Furthermore, the ceramics exhibited excellent coefficients of thermal expansion, implying the promising applicability of Y3(Nb1‐xTax)O7 as new thermal barrier materials. The effect of mass difference on the thermomechanical properties of the ceramics was examined, suggesting a simple strategy for engineering the chemical composition of new thermal barrier materials. [ABSTRACT FROM AUTHOR]

In this study, the addition of carbon nanotubes (MWCNT) and modified carbon nanotubes (MWCNT-COOH) in the range of 0.5 wt. % to 5 wt. % in polyamide (PA) obtained as a residue upon 3D printing, was investigated. PA and nanocomposite samples were prepared by melt mixing. PA/MWCNT and PA/MWCNT-COOH nanocomposites were characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), THB thermal conductivity determination method, electrochemical impedance spectroscopy (EIS), and tensile test. Results of DSC analysis showed that both types of carbon nanotubes (MWCNTs) acted as nucleation centres of PA matrix, but had no effect on the order of the crystalline structure. Due to the polar nature of the surface and better dispersion, MWCNT-COOH filler accelerated PA crystallization more significantly compared to MWCNT. Due to the presence of nanofiller, the PA chains had limited motion space, which interfered with the crystallization process of the matrix. The thermal stability of the PA matrix increased with the addition of both MWCNT and MWCNT-COOH fillers. Higher thermal conductivity was achieved with the addition of MWCNT-COOH filler compared to the addition of MWCNT. The results of the tensile test showed that with the addition of both types of MWCNT fillers in the PA matrix, the modulus of elasticity and yield stress had reduced, but the yield strain increased. Results of the EIS showed that MWCNT nanofiller had not changed the electrical conductivity regardless of modification.

Modification of biobased PLLA properties by mixing with conventional PMMA via melt mixing in Brabender mixer was performed. Despite negative results of theoretical miscibility calculations by the group contribution approach of Coleman, Graf and Painter, homogeneous blend morphologies were prepared as recorded with scanning electron microscopy (SEM). All PLLA/PMMA blends displayed a single glass transition temperature. With increasing fraction of PMMA in blends, the increase in Tg from 58 °C to 93 °C was recorded by differential scanning calorimetry (DSC). Added PMMA improved mechanical properties, while the flexibility of PLLA/PMMA blends gradually decreased as revealed by DMA measurements.

The elastomeric materials based on NR/BR/SBR ternary rubber blend were investigated. The polyisoprene (NR), butadiene (BR) and styrene butadiene (SBR) rubbers were used as network precursors and carbon black (CB) as an active filler (60 phr) for elastomeric materials preparation. For sample preparation, the mass ratio of NR to BR was constant, 1:1, but the SBR content was varied from 0 to 80 phr. The morphological, mechanical and thermal properties of prepared elastomeric materials were determined using scanning electron microscopy (SEM), mechanical tensile measurements and thermogravimetric analysis (TGA). Mechanical properties were assessed before and after thermooxidative aging during 168 h at 100 °C. The values of tensile strength, elongation at break, and hardness decrease up to 40 phr of SBR content and after that are increasing, but abrasion resistance of ternary rubber blends increases. Тhe thermal decomposition temperature obviously shifted to a higher temperature for the sample with 40 phr of SBR. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 45022 and Grant no. 45020]

A new type of poly(ether‐amide) thermoplastic elastomer (TPAE) was synthesized using poly(decamethylene terephthalamide (10T)/decamethylene isophthalamide) as hard segment and poly(ethylene glycol) as soft segment via an efficient, accessible and low‐pollution melt polymerization method. Thermoplastic elastomer was synthesized based on semi‐aromatic polyamide for the first time. The effects of various compositions of hard segments on the thermal and mechanical properties were investigated. The results show that TPAE synthesized from semi‐aromatic polyamide has excellent thermal stability, the initial decomposition temperature of all samples being between 370 and 378 °C. With an increase of 10T content, crystallization ability of the hard segment increased. As 10T content increased, TPAE changed from amorphous to crystalline, and the melting temperature ranged from 175 to 236 °C. Tensile testing revealed that TPAE had excellent and adjustable mechanical properties, and that tensile strength, elongation at break and elasticity modulus were in the ranges 7–40 MPa, 468–835% and 0.036–1.80 MPa. Furthermore, high‐temperature tensile test results showed that TPAE‐4 still maintained considerable mechanical properties, and had better mechanical properties compared with Pebax® 5533. In particular, TPAE‐4 had higher performance decay point for which elasticity modulus and stress at ε = 500% decreased rapidly when the temperature was higher than 80 °C, this point for Pebax® 5533 appearing at 50 °C. Such outstanding performance indicated that this new class of elastomer has the potential to be used in high‐temperature conditions. © 2020 Society of Industrial Chemistry [ABSTRACT FROM AUTHOR]

Nowadays, increasing attention is devoted to the search for polymeric composite materials that are characterized by reduced flammability. In this work, the layer-by-layer (LbL) technique was applied to form multilayered protective coatings for polyamide 6/montmorillonite (PA6/MMT) hybrid nanocomposites. This time, the double layers LbL deposition was used in order to improve the thermal properties or flammability of PA6 materials. Our goal was to check how five, 10, and 15 triple-layer deposition onto the surface of PA6 and PA6/MMT composites influenced these relevant properties. For this reason, disodium H-phosphonate, sodium montmorillonite, and iodo-bis(triphenylphosphino)copper were used for polyelectrolyte solution preparation. It was found that the LbL method could be successfully used to improve the flammability characteristics of polyamide 6-based composites. Nevertheless, the deposition of the copper complex should be combined with other flame retardants—preferentially containing phosphorus—which enable synergistic effects to occur. Moreover, microscopic observations confirmed that the surfaces on which the formation of interwoven fibrous crystal structures was observed had a tendency to protect the entire material against the destructive effects of heat, contributing, among other things, to reduce the maximum point of heat release rate (PHRR). [ABSTRACT FROM AUTHOR]

The last decade has witnessed multiple thermally responsive materials emerge as a significant class of stimuli‐responsive materials. These materials are elaborately designed and exert interesting properties. Herein, an overview of thermally responsive materials with respect to design strategies, fabrication procedures, and their applications is presented. Recently reported thermally responsive materials are highlighted. Then, applications of thermally responsive materials in bioimaging are summarized. Hot response: Recently reported thermally responsive materials are highlighted and the applications of thermally responsive materials in bioimaging are summarized. [ABSTRACT FROM AUTHOR]

A new and efficient catalyst of Na-Montmorillonite (Na+-MMT) was employed in this paper for α-methylstyrene (AMS) cationic polymerization. Maghnite clay, obtained from Tlemcen Algeria, was investigated to remove heavy metal ion from wastewater. “Maghnite-Na” is a Montmorillonite sheet silicate clay, exchanged with sodium as an efficient catalyst for cationic polymerization of many vinylic and heterocyclic monomers. The various techniques, including 1H-NMR, 13C-NMR, IR, DSC and Ubbelohde viscometer, were used to elucidate structural characteristics and thermal properties of the resulting polymers. The structure compositions of “MMT”, “H+-MMT” and “Na+-MMT” have been developed. It was found that the cationic polymerization of AMS is initiated by Na+-MMT at 0 °C in bulk and in solution. The influences of reaction temperature, solvent, weight ratio of initiator/monomer and reaction time on the yield of monomer and the molecular weight are investigated. The kinetics indicated that the polymerization rate is first order with respect to the monomer concentration. A possible mechanism of this cationic polymerization is discussed based on the results of the 1H-NMR Spectroscopic analysis of these model reactions. A cationic mechanism for the reaction was proposed. From the mechanism studies, it was showed that monomer was inserted into the growing chains.

Nucleophilic substitution on hexachlorocyclotriphosphazene (HCCTP) with allylamine in order to give hexa(allylamino)cyclotriphosphazene (HACTP) is performed for the first time under mild conditions by using diethylether as solvent to replace benzene which is very toxic. The reaction time is reduced to half and also performed at room temperature but especially in the presence of an eco-catalyst called Maghnite-H+. This catalyst has a significant role in the industrial scale. In fact, the use of Maghnite is preferred for its many advantages: a very low purchase price compared to other catalysts, the easy removal of the reaction mixture. Then, Maghnite-H+ is became an excellent catalyst for many chemical reactions. The structure of HACTP synthesized in the presence of Maghnite-H+ to 5% by weight is confirmed by 1H-NMR, 13C-NMR, 31P-NMR (Nuclear magnetic resonance) and FTIR (Fourier Transform Infrared spectroscopy). MALDI-TOF (Matrix-Assisted Laser Desorption/Ionisation-time-of-flight mass spectrometry) is used to establish the molecular weight of HACTP which is 471 g/mol. DSC (Differential Scanning Calorimetery) and TGA (Thermogravimetric Analysis) show that HACTP is a crystalline product with a melting point of 88 °C. It is reactive after melting but is degraded from 230 °C.

Choice of alkali cation in mix design of geopolymers is critical for their thermal performance. However, the influence of alkali cation type on strength endurance of geopolymers subject to high temperature exposure and the underlying governing mechanisms have not been studied. This study investigated the effects of alkali cation type on high temperature response of fly ash geopolymers aiming towards structural applications. In-depth investigation was carried out to discover the underlying mechanisms governing the strength endurance of fly ash geopolymers subject to high temperature exposure and its correlation with their volume stability and chemical stability. Results showed that potassium geopolymer exhibited significant strength enhancement (30–40%) and sodium geopolymer displayed reduced strength (10%), and the strength of mixed sodium and potassium geopolymer remained unchanged after exposure to elevated temperature. While the binders were chemically stable without deterioration and formation of new crystal phases after high temperature exposure, the volume stability varied with the type of alkali cation used. Formation of cracks and gel densification due to shrinkage, and healing of micro-cracks and change of pore sizes due to sintering were identified as responsible mechanisms at different temperature ranges. While crack development and enlargement of pores lowered the strength, densification of matrix and healing of micro-cracks favored strength gain. These competing mechanisms determine the strength endurance of geopolymers depending on the type of alkali cation used. Overall, it shows that geopolymers can be tailored, such that stable (or even enhanced) strengths upon thermal exposure are realized, for structural applications. [ABSTRACT FROM AUTHOR]

ABSTRACT: Two novel fluorene functionalized polyacetylenes with different conjugation bridge architectures (stilbene and azobenzene), poly[2‐[4‐vinyl‐4′‐(N‐methyl, N‐ethyl‐yl propargyloxy) phenyl azo]‐9,9‐dioctylfluorene] (PC1), poly[2‐[4‐vinyl‐4′‐(N‐methyl, N‐ethyl‐yl propargyl group) stilbene ethenyl]‐9,9‐dioctylfluorene] (PC2), were designed and prepared through using [Rh(nbd)Cl]2‐Et3N as the catalysts, respectively. These polymers are soluble in common organic solvents, such as toluene, chloroform, 1,2‐dichloromethane, and tetrahydrofuran, which their structures and properties were systematically characterized by means of Fourier transform infrared spectroscopy, nuclear magnetic resonance, elemental analyses, UV–vis, photoluminescence, thermogravimetric analysis, gel permeation chromatography, and Z‐scan technique. The optical limiting properties were investigated at 780 nm with 450 fs laser pulses. Remarkably, it is expected that, by incorporation of fluorene into functional polyacetylene has endowed the resultant polymers with well optical limiting properties and thermal stability. Additionally, the nonlinear optical properties of functionalized polyacetylenes were significantly affected by different molecular structure of conjugated bridge of substituted group. The polyacetylenes with azobenzene (PC2) conjugated bridge displaying well two‐photon absorption cross‐sections of 3950 cm/GM (2010 cm/GM for PC1 containing stilbene), owning to stronger π‐conjugated chromophores of objective polymer and intramolecular charge transfer effect. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46100. [ABSTRACT FROM AUTHOR]

ABSTRACT One of disadvantages of polymer composites is poor electrical and thermal conductivity. As a first step in this direction, graphene-modified polypropylene polymer is being developed to improve its electrical and thermal conductivity. Two techniques were investigated: surface coating and extrusion. In the case of coating technique, the percolation threshold was found to be 0.5 wt % of graphene and electrical conductivity of polypropylene increased around 13 log cycles. Coating technique breaks the agglomerations due to magnetic stirring followed by sonication and gives homogeneous graphene-coated polypropylene pellets. When polymer melts under compression molding, the graphene platelets network formed on the surface of polypropylene pellets as well as through-the-thickness of the molded disk, which provide continuous network of graphene. However, in extrusion technique, graphene segregated and did not disperse properly in polypropylene. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45833. [ABSTRACT FROM AUTHOR]

Froth flotation is one of the most frequently used processes for separation of valuable from gangue minerals. Modeling and simulation of the flotation process is a difficult task because of nonlinear and dynamic nature of the process. In this contribution, the relationship between the process variables (i.e., gas flow rate, slurry solids%, frother/collector dosages, and pH) and the metallurgical parameters (i.e., copper/mass/water recoveries and concentrate grade) in the batch flotation of a copper sulfide ore is discussed and modeled. Statistical (i.e., nonlinear regression) and intelligent (i.e., neural network and adaptive neuro-fuzzy) techniques are applied to model the process behavior at different conditions. The results indicate that intelligent approaches are more efficient tools for modeling of the complicated process like flotation, which are of central importance for development of the model-based control systems. [ABSTRACT FROM PUBLISHER]

This paper deals with an analytical method to assess the maximum temperature value along a tubular chemical reactor at steady state. This reactor is provided with a jacket in which a counter current cooling liquid flows. The thermal behavior of the chemical reactor is calculated with the McCormack numerical method. Comparison of the exothermic reaction generated flux with the removed flux from the separating wall leads to a two-part reactor subdivision. In the first part, the reactor behaves as an adiabatic reactor followed by a zone in which the flux removed from the wall is not negligible and remains constant. In the second part, the reactor behaves like a simple heat exchanger without internal energy source. Analytical integration of mass and energy balance equations in each subsystem was used to determine the analytical expression of maximum temperature. [ABSTRACT FROM PUBLISHER]

The present study is the first part of research into modeling flocculation processes in a tubular reactor with different width baffles. Computational fluid dynamics numerical simulation methods were used to identify intensive mixing zones and turbulent flow zones. The influence of geometry and baffle width on velocity components of the liquid flow and turbulence parameters was analyzed. The obtained results were represented as vector and contour distribution maps of the determined quantities. Flow visualization was performed to illustrate the structure and size of vortices formed behind baffles. The correctness of the numerical model was experimentally validated based on anemometric measurements using laser Doppler anemometry (LDA) method. [ABSTRACT FROM PUBLISHER]

Reversible luminescence modulation upon photochromic reactions with excellent reproducibility was achieved from Eu3+ doped Bi2.5Na0.5Nb2O9 multifunctional ferroelectrics. The material exhibits strong sensitivity to visible light or sunlight with fast response time without inducing any structural changes. [ABSTRACT FROM AUTHOR]

Biodegradable polymer blends prepared by blending poly(3-hydroxybutyrate) (PHB) and corn starch do not form intact films due to their incompatibility and brittle behavior. For improving their compatibility and flexibility, poly(vinyl acetate) (PVAc) was grafted from the corn starch to prepare the PVAc-modified corn starch (CSV). The resulting CSV consisted of 47.2 wt% starch- g-PVAc copolymer and 52.8 wt% PVAc homopolymer and its structure was verified by FT-IR analysis. In comparison with 35°C of the neat PVAc, the glass transition temperature ( Tg) of the grafted PVAc chains on starch- g-PVAc was higher at 44°C because of the hindered molecular mobility imposed from starch on the grafted PVAc. After blending PHB with the CSV, structure and thermal properties of the blends were investigated. Only a single Tg was found for all the PHB/CSV blends and increased with increasing the CSV content. The Tg-composition dependence of the PHB/CSV blends was well-fitted with the Gordon-Taylor equation, indicating that the CSV was compatible with the PHB. In addition, the presence of the CSV could raise the thermal stability of the PHB component. It was also found that the presence of the PHB and PVAc components would not hinder the enzymatic degradation of the corn starch by α-amylase. POLYM. ENG. SCI., 55:1321-1329, 2015. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

New oleogel formulations based on high-oleic sunflower oil (HOSO) and ethylene vinyl acetate copolymer (EVA)/polypropylene (PP) blends were prepared using the mixing rheometry technique and further characterized. The effects of PP tacticity and EVA vinyl acetate (VAc) content on the rheological, morphological, and thermal behavior of derived oleogels were investigated. Differential scanning calorimetry (DSC) and polarized-light optical microscopy (PLOM) observations indicated that VAc segments markedly influence the crystalline structure of polymeric fractions and phase morphology of oleogels. The normalized crystallinity of isotactic polypropylene (iPP) phase increased linearly with its concentration whereas syndiotactic polypropylene (sPP) content does not exert a significant influence. PLOM observations showed that VAc content plays an important role in the phase morphology of PP frictions (size and shape of crystals). The viscoelastic response of oleogels depended on PP tacticity and VAc content, which may be explained attending to the different microstructures attained. POLYM. ENG. SCI., 55:1429-1440, 2015. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

To study the relation between cold-hot-water mixing ratio and outlet-water temperature of a mixer, the geometrical model of the mixer was built. On the basis of theoretical analysis, the outlet-water temperature with different mixing ratio of cold and hot water was simulated by FLUENT software. The results show that: flow field in mixer can be divided into recirculation zone and convection zone, in which there are different thermal resistances individually, and it result in the nonlinear relation in outlet average temperature and mixing ratio; there is a linear relation between outlet average velocity and mixing ratio, which accords to the mass conservation principle of non-compressible and continuous fluid flow. [ABSTRACT FROM AUTHOR]