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The widespread application of polylactide (PLA) has been limited by its slow crystallization rate and poor toughness. In the present work, a low molecular weight nucleator, TMC 301, and polyamide elastomer (PAE) were incorporated into PLA through melt blending to mediate both the crystallization capability and impact toughness. It was found that the introduction of TMC 301 decreased the crystallization temperature of PLA during the cooling process, while enhancing its cold crystallization capacity of PLA in the heating scan. Accordingly, the presence of TMC 301 shortened the half-crystallization time of PLA at 95°C in the ternary blends with minimal influence on the Avrami index. Moreover, the dispersion size of PAE decreased when the concentration of TMC 301 increased to 0.3 wt%, leading to a substantial increase in the tensile toughness and the impact strength of the PLA/PAE/TMC 301 blend. It is suggested that the size of the elastomer particles is a critical factor influencing the toughening efficiency of TMC301 in PLA/PAE blends. The nucleator TMC 301 and polyamide elastomer (PAE) were incorporated into PLA through melt blending to enhance both crystallization capability and toughness. The phase structure, crystallization behavior and the mechanical performances were studied. [ABSTRACT FROM AUTHOR]

Investigating the effects of different segment compositions in block copolymers on their performance is crucial for enhancing material properties and developing new applications. In this study, we investigate the impact of differing segment compositions on the crystallization behavior, microphase separation characteristics, and physical properties of Poly(vinylcyclohexane)-b-poly(ethylene)-b-poly(vinylcyclohexane) (PVCH-PE-PVCH) block copolymers. In PVCH-PE-PVCH block copolymers, the longer PE segments significantly enhance crystallization capability and order. These long PE segments not only facilitate more effective microphase separation, promoting the formation of larger structural domains, but also favor the crystallization of the PE phase, thereby markedly improving the material's mechanical and optical properties. This reveals the pivotal role of the synergistic effect between long-chain PE distribution and microphase separation in regulating the structure and performance of high-performance polymer materials. Although theoretically, high PE content and high molecular weight are conducive to performance enhancement, this was not fully realized under conditions of weak phase separation capability and shorter PE chains. Therefore, we emphasize that optimizing the performance of these high-performance block copolymers through precise molecular design is feasible, providing powerful strategies and theoretical support for designing novel materials with specific functionalities. [ABSTRACT FROM AUTHOR]

Elemental tellurium, a prototypical one‐dimensional van der Waals material, has recently been found to crystallize quickly from the liquid on a nanosecond timescale, yet the inherent mechanism is not clear. Here, by combining in situ high‐energy synchrotron radiation X‐ray diffraction with ab initio molecular‐dynamics simulation, it is found that trigonal crystalline Te completely melts into the liquid phase at 450 °C, and recrystallizes into the trigonal phase for temperatures lower than 380 °C without the formation of any other phase. This directly confirms the recent proposal of a crystal‐liquid‐crystal phase transition in this material underlying the observed electrical‐switching process. Atomic‐scale, melt‐quench computer simulations show that liquid Te is capable of crystallizing within a time of 25 ps in the vicinity of templating crystallization interfaces. This ultrafast crystallization ability of Te can be understood as being due to delayed Peierls distortions during a quench and therefore a high atomic mobility over a wide range of temperature. This finding opens the way to develop a crystal‐liquid‐crystal, phase‐transition‐based selector switch with an ultrafast switching speed. [ABSTRACT FROM AUTHOR]

Effects of Li 2 O additive on the network structure, crystallization behavior, thermal expansion properties and wettability of Y 2 O 3 -Al 2 O 3 -SiO 2 glass were investigated. The results showed that Li 2 O could depolymerize the network structure, decreasing the characteristic temperatures of glass. The coefficient of thermal expansion of glasses varied from 5.09×10−6 K−1 to 8.03×10−6 K−1 by changing the Li 2 O addition and heat treatment process. Meanwhile, Li 2 O inhibited the crystallization of high-melting phases, consequently improving the fluidity of molten glass. The glass with 3 wt% Li 2 O showed an excellent wettability on SiC ceramic with a contact angle of 18°, and a sound joint mainly consisted of glassy phase was obtained at 1430 ℃ for 30 min. The prepared joints exhibited a shear strength of 119.7±20.3 MPa, which is 5.4 times of that without Li 2 O. After 3 times of water-quenching from 1200 ℃, the joints remained 68.4% of its original strength, demonstrating graceful reliability. • A series of Y 2 O 3 -Al 2 O 3 -SiO 2 -Li 2 O glass filler was newly-designed for SiC brazing. • Effect of Li 2 O on the glass structure, crystallization and thermal expansion properties was revealed. • Li 2 O improved the fluidity of molten glass by inhibiting the formation of high-melting precipitates. • Addition of Li 2 O increased the shear strength of SiC/SiC joint by 4.4 times (119.7±20.3 MPa). [ABSTRACT FROM AUTHOR]

Bulk glass-ceramic solid electrolytes of the Li 2 O–Al 2 O 3 –TiO 2 –P 2 O 5 –SiO 2 system were prepared by melt-quenching and one-step heat treatment method in this work. The effects of the gradual substitution of Al3+ by Cr3+ and the elevation of the heat treatment temperature on the phase composition, microstructure, and ionic conductivity of the solid electrolytes were systematically investigated. The results show that the major crystalline phase is LiTi 2 (PO 4) 3 , and the conductivity of the glass-ceramics initially enhances and then decreases as the Cr 2 O 3 content increases from 0 mol% to 3 mol%. The highest conductivity is obtained when the Cr 2 O 3 content is 2 mol%, measuring 4.45 × 10−4 S/cm at 25 °C. Additionally, the mechanism of the surface exfoliation of the glass-ceramics and the enhancement achieved by doping with Cr3+ are explained according to microstructure analysis. This work provides a simple method to enhance the electrical conductivity and physical properties of LATP glass-ceramic solid electrolytes, which is of great significance for the design of lithium-ion solid electrolytes. [ABSTRACT FROM AUTHOR]

In order to explore the crystallization behavior of Co‐doped amorphous manganese dioxide(Co‐doped AMO) and to investigate the electrochemical properties of its different crystallization products as cathodes for aqueous zinc ion batteries. In this work, the effects of heat treatment temperature on the microstructure and phase composition of Co‐doped AMO and their electrochemical properties of Zn‐MnO2 battery cathode materials are systematically investigated. The results show that Co‐doping increases the crystallization temperature of pure AMO. When the heat treatment temperature is 400 °C, Co‐doped AMO is amorphous. At 500 and 550 °C, part of the Co‐doped AMO crystallizes into tetragonal spinel structured (Co, Mn)(Co, Mn)2O4 material between MnCo2O4 and Mn3O4. At 650 °C, the crystallized product is completely nano‐α‐Mn(Co)O2 crystal. The maximum discharge specific capacities and the retention rate after 100 cycles of the samples at 100 mA g−1 are 325.40 mAh g−1, 86.88%; 217.00 mAh g−1, 13.94%; 186.68 mAh g−1, 41.01%; and 149.03 mAh g−1, 31.27% for the unheated and 400, 550, 650 °C heat‐treated samples, respectively. It is proved that the Co‐doped AMO without heat treatment is superior to the partially or fully crystallized materials in terms of comprehensive performance and cost as cathode materials for AZIB. [ABSTRACT FROM AUTHOR]

In the current study, the influence of TiO 2 /SiO 2 and BaO/CaO ratios on viscosity, crystallization and structure of high-TiO 2 mold slags was discussed through the measurement of viscosity-temperature relationship, melting temperature, crystallization temperature, crystallization rate and phases, and Raman spectrum. With the substitution of SiO 2 by TiO 2 in slags from 0 % to 12 %, the viscosity at 1300 °C, the melting temperature and break temperature decreased and then increased, while those of slags with the substitution of CaO by BaO from 4 % to 16 % decreased. With the substitution of SiO 2 by TiO 2 from 0 % to 10 %, crystallization phases gradually changed from cuspidine (Ca 4 Si 2 F 2 O 7) to perovskite (CaTiO 3), the initial and complete crystallization temperatures had the tendency to increase from 918 °C to 1260 °C and from 857 °C to 1139 °C, respectively, and the overall crystallization ability of slags increased. With the substitution of CaO by BaO from 4 % to 16 %, the initial and complete crystallization temperature of these slags decreased, and the overall crystalline ability decreased. With the substitution of SiO 2 by TiO 2 from 0 % to 10 %, structural units changed from the simple units to complex units, but the transition was opposite with the substitution from 10 % to 12 %, which was related to the transition of TiO 2 from basic oxide to amphoteric oxide. With the substitution of CaO by BaO from 4 % to 16 %, the degree of polymerization and the viscosity of theses slags decreased, which was related to the supplement of more active O2− ion from BaO. Hence, the excessive substitution of SiO 2 by TiO 2 under the steel-slag reaction would cause the increase of the slag viscosity and crystallization ability, while the substitution of CaO by BaO could weaken the variation of slag viscosity and crystallization ability. [ABSTRACT FROM AUTHOR]

Nanoscratching introduces detrimental surface and subsurface defects like amorphous regions, dislocations, and stacking faults in monocrystalline silicon, hindering its application in microelectronics and high-performance optics. This study leverages in-situ transmission electron microscopy to unveil the thermal evolution of these defects in atomic scale. A key finding is the amorphous phase recrystallization starting at ∼500 °C. Epitaxial growth from the crystalline-amorphous boundary, guided by adjacent crystal planes, restores the original diamond structure phase. By 700–800 °C, almost complete recrystallization occurs, maintaining similar interplanar spacing despite residual crystal distortions and dislocations. Notably, heating above 600 °C results in the gradual vanishing of stacking faults, suggesting a dynamic thermal evolution of the crystal defects induced by surface nanoscratching. This work demonstrates thermal annealing as a promising strategy to mitigate nanoscratch-induced defects, paving the way for defect-free-surface of silicon components in ultra-precision machining processes. It offers valuable insights into the interplay between nanoscratching, temperature, and defect evolution, laying the groundwork for surface and subsurface defects elimination in silicon under thermal fields.

Environmental barrier coatings (EBCs) with thermomechanical robustness against calcium–magnesium–aluminum–silicate (CMAS) deposits are in high demand. The aim of this work was to clarify the influence of Sc3+ on the crystallization behavior of Yb-based coatings against CMAS deposits. The reaction products of solid solutions with compositions traversing the Sc2O3–Yb2O3 system indicate that Sc3+ tends to form [BO6] coordination polyhedra in the crystal structure to promote the formation of garnet and diopside, while Yb3+ occupies 7-, 8-, and 9-coordinate sites to crystallize apatite and silicocarnotite. The transformation of crystalline products from apatite/silicocarnotite to garnet/diopside greatly improves the efficiency of CMAS melt consumption and facilitates the prevention of its further penetration and corrosion. Based on the commonality of cation occupancy in crystallography, an A(CaO+YbO1.5)–B(ScO1.5+MgO+AlO1.5)–T(SiO2) pseudoternary phase diagram is established, which has great potential for describing phase equilibrium in coating-deposit systems and can provide guidance for the compositional design of corrosion-resistant coatings.

In this study, the effects of Si content on the glass-forming ability (GFA), thermal stability, annealing window, nanocrystallization process, and soft magnetic properties (SMPs) of Fe86.3-xSixB10P2Cu1.7 (x = 0, 1, 2, 3, and 4, denoted as Si0, Si1, Si2, Si3, and Si4, respectively) alloys with high Fe and Cu contents were investigated. Moderate addition of Si (x = 1, 2, and 3) enhanced the GFA and suppressed the precipitation of compound phases, thus leading to a large crystallization temperature interval (ΔTx) exceeding 185 °C for the alloys. Appropriate addition of Si also resulted in the formation of high-density and fine pre-existing α-Fe nanocrystals in as-spun ribbons and a high growth active energy of α-Fe crystals during the subsequent nanocrystallization process for the Si1, Si2, and Si3 alloys, enhancing competitive growth between α-Fe crystals and resulting in fine nanostructure and excellent SMPs of the nanocrystalline alloys (NAs). As a result, the Si1, Si2, and Si3 NAs obtained by annealing at 420 °C for 30 min exhibited excellent SMPs with saturation magnetic flux density (Bs) up to 1.84 T and a low coercivity (Hc) of approximately 10 A/m. In addition, statistical analysis of the relationship between the average grain size (D) of α-Fe crystals and Hc values of the NAs indicated that an Hc α D3 dependence is observed when the D is less than approximately 30 nm, while this dependence follows the well-known Hc α D6 relationship when the D is above 30 nm. The dependency relationship between D and Hc of NAs can guide the selection of an appropriate annealing process to optimize their SMPs.

Ti-Zr alloy blanks were successfully prepared by low-temperature liquid-phase sintering at 1000 °C using GH4169 alloy powder as an additive. Then, the crystallization and organization evolution laws of Ti-Zr alloy under different holding time conditions during the sintering process were studied in detail. Research shows that, when the holding time reached 30 min, the sintered alloy contained α-phase, β-phase, and titanium oxide phases. The average grain sizes of the α-phases and β-phases matrix are in the ranges of 100 to 300 nm and 50 to 80 μm, respectively. However, when the holding time was less than 20 min, the temperature gradient dropped greatly due to an instantaneous power failure during the spark plasma sintering process, which made it too late for the liquid phase at the grain boundaries to crystallize and caused the amorphous phase to form between them. Subsequently, the α-transition phase first precipitated and then, transformed into the β-phase. The α-transition phase mainly precipitated in the (12 3 ¯ 5) [ 5 5 ¯ 01 ] orientation, while the β-phase mainly precipitated in the (11 4 ¯) [ 1 1 ¯ 0 ] and 161 ⟨ 4 1 ¯ 2 ⟩ orientations, with the preferred orientation being 114 [ 1 1 ¯ 0 ] . [ABSTRACT FROM AUTHOR]

To solve the decrease in the crystallization, mechanical and thermal properties of recycled polyethylene terephthalate (rPET) during mechanical recycling, the aromatic amide fatty acid salt nucleating agents Na-4-ClBeAmBe, Na-4-ClBeAmGl and Na-4-ClAcAmBe were synthesized and the rPET/nucleating agent blend was prepared by melting blending. The molecular structure, the thermal stability, the microstructure and the crystal structure of the nucleating agent were characterized in detail. The differential scanning calorimetry (DSC) result indicated that the addition of the nucleating agent improved the crystallization temperature and accelerated the crystallization rate of the rPET. The nucleation efficiencies (NE) of the Na-4-ClBeAmBe, Na-4-ClBeAmGl and Na-4-ClAcAmBe were increased by 87.2%, 87.3% and 41.7% compared with rPET which indicated that Na-4-ClBeAmBe and Na-4-ClBeAmGl, with their long-strip microstructures, were more conducive to promoting the nucleation of rPET. The equilibrium melting points (T 0 m) of rPET/Na-4-ClBeAmBe, rPET/Na-4- ClBeAmGl and rPET/Na-4-ClAcAmBe were increased by 11.7 ◦C, 18.6 ◦C and 1.9 ◦C compared with rPET, which illustrated that the lower mismatch rate between rPET and Na-4-ClBeAmGl (0.8% in b-axis) caused Na-4-ClBeAmGl to be the most capable in inducing the epitaxial crystallization and orient growth along the b-axis direction of the rPET. The small angle X-ray diffraction (SAXS) result proved this conclusion. Meanwhile, the addition of Na-4-ClBeAmGl caused the clearest increase in the rPET of its flexural strength and heat-distortion temperature (HDT) at 20.4% and 46.7%. [ABSTRACT FROM AUTHOR]

Single (TiO2) and complex (TiO2 and ZrO2) nucleating agents were added in CaO–Al2O3–SiO2–ZnO–Na2O–K2O‐based multicomponent glass to investigate its crystallization behavior and physical properties according to the types and amounts of nucleating agents. Nonisothermal analysis revealed crystallization behavior with an activation energy (E) of 165.176–518.985 kJ/mol and Avrami constant (n) of.73–2.12 with the complex nucleating agent. X‐ray diffraction was used to observe the titanite and zircon crystalline phases in glass when using complex nucleating agents, and the crystallinity was found to be 43%–55%. Scanning electron microscopy and energy‐dispersive x‐ray spectroscopy were used to observe the plate‐shaped titanite and column‐shaped zircon crystalline phase in the glass matrix, and the glossiness was found to be decreased owing to the crystallization of the glass. The glass‐ceramic showed a higher hardness and fracture toughness value of 6.45–6.7 GPa and 1.54–3.35 MPa∙m1/2 when using the complex nucleating agent rather than when using the single nucleating agent. [ABSTRACT FROM AUTHOR]

POE was used to modify polypropylene (PP) to improve paint adhesion on the surface of PP material for automotive interior. By means of differential scanning calorimetry, scanning electron microscope, Dyne pen, Paints Crosscut test and mechanical property test, the effects of POE on crystallization property, dispersion ability, surface tension, paint adhesion and mechanical properties of modified PP were investigated. The results show that with the increase of POE, the tensile yield strength and bending modulus of modified PP decrease, and the notch impact strength increases. The higher melt flow rate (MFR) of POE, the greater the reduction of rigidity. The higher the content of POE, the more favorable it is to improve the surface adhesion of modified PP. When the POE content is not less than 15%, the Paints Cross-cut test level of the template reaches 0. The higher the MFR of POE, the more conducive to the orientation and dispersion of the rubber phase on the surface of the template, which is conducive to the immersion of the paint and the improvement of the paint adhesion. When the paint film thickness is less than 26 μm, it is difficult to form an effective and dense paint film on the surface of the template, resulting in poor paint adhesion of the template. When the paint film thickness is not less than 26 μm, the template paint adhesion is better. [ABSTRACT FROM AUTHOR]

Serious shrinkage and warpage are obstacles to the development of ideal isotactic polypropylene (iPP) materials for polymer‐based powder bed fusion (PBF) technique. In this work, the variations of the dimensional accuracy of the PBF‐printed iPP parts were investigated with various printing parameter and nucleating agent. The iPP parts printed at a scanning speed of 700 mm/s exhibit smaller extents of shrinkage and curling than those at lower speeds, due to a lower degree of crystallinity. Interestingly, iPP blended with the α‐ or β‐nucleating agent demonstrates more serious part deformation with respect to neat iPP. Especially, α‐nucleating agent tends to trigger the most severe curling under the investigated printing parameters. Based on X‐ray diffraction and differential scanning calorimetry (DSC) results, both neat iPP and α‐iPP parts crystallize into α‐crystal, while β‐iPP parts display the coexistence of β‐ and α‐crystals. And, the difference of the crystallinity is less than 3% in three specimens. This suggests that both crystallinity and crystalline structure are not the main reasons for the shrinkage and warpage in this case. Instead, the severe part deformation of the α‐iPP parts is assigned to the narrower sintering window as well as the higher onset crystallization temperature of α‐iPP, which hinder relaxation of residual stresses. This work provides insights into the part deformation mechanism for PBF‐processed polymer materials. [ABSTRACT FROM AUTHOR]

For a polymer/polymer dismissible blend with two crystallizable components, the crystallization behavior of different components and the reciprocal influences between different crystals are interesting and important, but did not investigate in detail. In this study, the L-poly(lactic acid)/polypropylene (PLLA/PP) blends with different weight ratios were prepared by melt mixing and the crystallization behavior of the blends were investigated. Results showed that the crystalline structures of PLLA and PP were not altered by the composition. For the crystallization of PLLA, both the diffusion of chain segments and crystallization rate were enhanced under the existence of PP crystals. For the crystallization of PP, its crystallization rate was depressed under the existence of amorphous PLLA molecular chains. When the PP crystallized from the existence of PLLA crystals, although the diffusion rate of PP was reduced by PLLA crystals, the nucleation positions were obviously enhanced, which accelerated the formation of PP crystals. This investigation would supply more basic data for the application of PLLA/PP blend. [ABSTRACT FROM AUTHOR]

Maleic anhydride grafted linear low density polyethylene/graphene (LLDPE-g-MAH/G) nanocomposites were prepared by melt blending. The effects of different graphene content on the crystallization behavior, rheological properties and mechanical properties of LLDPE-g-MAH/G nanocomposites were investigated. The results show that with the increase of graphene content, the crystallinity and long period of the composites increase gradually, the storage modulus, loss modulus and complex viscosity increase first and then tend to be gentle, and the tensile strength and elongation at break increase first and then decrease with the increase of graphene content. When the graphene content is 0.5%, the mechanical properties of the nanocomposites are the best, and the tensile strength and elongation at break reach 26.8 MPa and 998%, respectively. When the graphene content is 0.5%, the polyethylene crystal and graphene in the stretched nanocomposites are oriented along the stretching direction at the same time, so that the original crystal in the nanocomposites is damaged and broken, the crystal size is reduced, and the melting point is reduced. The thermal conductivity of the nanocomposites along the tensile direction after stretching is 3.6 times that before stretching, and the thermal conductivity is greatly improved. [ABSTRACT FROM AUTHOR]

The matrix material used in this paper was low-density polyethene (LDPE), and the added particles selected were silicon oxide (SiO2) particles and montmorillonite (MMT) particles. The sizes of the SiO2 particles were 1 µm, 30 nm, and 100 nm, respectively; three kinds of SiO2/MMT/LDPE multi-component composites were prepared based on MMT/LDPE composites doped with MMT particles. The effect of the SiO2 particle size on the crystallization behavior and space charge properties of SiO2/MMT/LDPE composites was studied. The crystalline behaviors and crystallinity of the materials were analyzed. At the same time, the changes in the relative dielectric constant εr and loss factor tanδ for each material with the influence of frequency were studied, and the space charge accumulation, residual characteristics, and apparent charge mobility of each material were explored. The results show that the smaller the size of the added particles, the smaller the grain size and the clearer the grain outline for the multi-composite material. After adding 30 nm SiO2 particles, the crystallinity of the material increases significantly. The microstructure formed by the addition of 100 nm SiO2 particles effectively restricts molecular chain movement and makes it difficult to establish the polarization of the composite. The incorporation of large-size particles can reduce the proportion of the crystalline structure for the material as a whole, resulting in the formation of a new structure to promote charge transfer. Among the three kinds of SiO2 particles, the addition of 30 nm SiO2 particles can effectively suppress the space charge, and the composite material has the lowest residual space charge after depolarization. The addition of 100 nm SiO2 particles can cause the accumulation of many homopolar charges near the anode. [ABSTRACT FROM AUTHOR]

Polyamide6 is a vital high-performance commercial engineering thermoplastics polymer, but it exhibits low toughness and high hydrophilicity. To improve its disadvantages, the facile melt co-polycondensation method was proposed to synthesis a novel polyamides 6-1012 copolymers (PA6-1012) with different PA1012 salt loading. Experimental results show that the melting temperature (Tm), crystallization temperature(Tc), melting enthalpy(ΔHm), and crystallinity(Xc) decreased with the increase of PA1012 loading in the copolyamides. The size and number of the copolymers' spherical crystals decrease by the additions of 1012 units, but its crystalline structure and thermal stabilities does not be affected. The hydrophilicity decreases with increasing PA1012 content from 0 to 28 wt% and the highest contact angle value at the PA1012 loading of 28 wt% is 96°, which can be considered as a surface hydrophobic material. Low temperature (−5 °C)mechanical test results reveal that loss in tensile strength is exchanged for a considerable increase in the strain at break. The impact strength of the PA6-1012 copolyamides is notably enhanced by increasing the PA1012 loading in different test temperatures due to the increase of molecular chain flexibility, indicating that the copolyamindes exhibit enough toughness to suitably apply in low temperature environment. [ABSTRACT FROM AUTHOR]

Ferrite process exhibits promising potential as a technological solution for the treatment of chromium-containing wastewater, owing to its dual functionality in both purifying the wastewater and facilitating resource utilization. Nickel ions often coexist in chromium-containing electroplating wastewater because of the need for an electroplating process. When the ferrite process treats chromium-containing electroplating wastewater, coexisting nickel ions will enter the synthetic spinel crystals and affect their properties. In the study, the effects of nickel ions on properties of spinel synthesized in mixed wastewater containing chromium were investigated by atomic absorption spectroscopy (AAS), toxicity characteristic leaching procedure (TCLP), physical property measurement system (PPMS), and the effect mechanism was clarified by X-ray diffraction (XRD), toxicity characteristic leaching procedure (TCLP), scanning electron microscope (SEM) and energy dispersion spectrum (EDS).The findings suggested that the presence of nickel ions had minimal impact on both the quality of the filtrate and the stability of chromium in the products synthesized under room temperature conditions and an initial pH level of 12. Interestingly, it was observed that a moderate concentration of nickel ions significantly enhanced the magnetic properties exhibited by these products. However, excessive nickel ions resulted in a reduction in the magnetic properties of the synthetic solid substance. The crystallinity degree of the synthetic solid substance gradually degenerated as the reaction time increased. Compared to nickel ions, chromium ions more quickly entered the synthetic spinel structure. Finally, the stable nickel-containing spinel was formed when the reaction time was over 20 min, but the crystallinity degree of the synthetic solid substance was inferior. [ABSTRACT FROM AUTHOR]

Al 2 O 3 ceramic addition in glass significantly influenced thermal performance during sealing process in RSOC stack. The effect of Al 2 O 3 ceramic on crystallization behavior, phase compositions, microstructure, and viscosity of glass were discussed. With increasing Al 2 O 3 ceramic content, the crystallization activation energy of glass gradually increased. The crystallization behavior of glass was effectively suppressed with Al 2 O 3 ceramic addition. The glass with 20 wt% Al 2 O 3 ceramic exhibited that the content of BaAl 2 Si 2 O 8 crystallization phase remained at around 45 wt% after heat-treated at 750 °C for 300 h. The controlled hexagonal BaAl 2 Si 2 O 8 crystallization content combining with Al 2 O 3 ceramic in seals effectively adjusted viscosity at about 105.1 Pa s and 107.2 Pa s during 700 °C–900 °C. During sealing process, the moderate Al 2 O 3 ceramic and BaAl 2 Si 2 O 8 were embedded in glass matrix acting as frame to enhance structural stability. Simultaneously, the glass phase owned proper fluidity, which could infiltrate components and ceramic without wide flow and release thermal stress during sealing. [ABSTRACT FROM AUTHOR]

The morphology and thermal properties of PHBV/PHO/starch blends are investigated using polarized optical microscopy, differential scanning calorimetry, thermal gravimetric analysis, and X-ray diffraction. The crystallization behavior of the PHBV in PHBV/PHO was improved via the incorporation of a biodegradable nucleating agent, starch, as indicated by thermal analysis and polarized optical micrographs. The PHBV and PHO show phase separation in the blend. The XRD patterns of PHBV in blends are identical to those of neat PHBV. The Avrami exponents were not considerably impacted by the presence of PHO or starch. Furthermore, the nucleation constant, Kg, of the PHBV blends was evaluated using a modified Lauritzen–Hoffmann treatment. The Kg values indicated that the crystallization of PHBV in all blends occur in Regime III. PHO and starch have little impact on the maximum degradation temperature of PHBV. [ABSTRACT FROM AUTHOR]

In the current study, the influence of different BaO/Al 2 O 3 ratios and Li 2 O contents on the viscosity, melting temperature, crystallization behavior and structure of BaO–Al 2 O 3 –TiO 2 -based mold slags was investigated through the measurement of the viscosity-temperature relationship, hemisphere point method, crystallization process and crystallization temperature, and the calculation of NBO/T and optical basicity. With the increase of the BaO/Al 2 O 3 ratio from 0.60 to 1.67, the viscosity at 1573 K and the melting temperature of mold slags decreased from 0.3 to 0.05 Pa s, and 1261 K–1217 K, respectively, while those also slightly decreased from 0.15 Pa s to 0.11 Pa s, and 1244 K–1213 K with the Li 2 O content from 4 % to 6 %, respectively, which was related to the increase of fluxing reagent or oxygen ions released by basic oxide in slags. In current slags, precipitated phases mainly existed as LiTiO 2 and BaTiO 3 , and the difference of the BaO/Al 2 O 3 ratio and Li 2 O content resulted in the competitive precipitation of these phases. With the increase of BaO/Al 2 O 3 ratio from 0.60 to 1.67, precipitated phases gradually changed from LiTiO 2 to BaTiO 3 , and the initial crystallization temperature had the tendency to decrease and increase. On the contrary, the precipitated phase gradually changed from BaTiO 3 to LiTiO 2 , and the initial crystallization temperature as well as the break temperature decreased with the Li 2 O from 4 % to 8 %. The parameter NBO/T and optical basicity of molten slags increased with the increase of BaO/Al 2 O 3 and Li 2 O content, and the polymerization degree of the melt decreased, resulting in the decrease of the activation energy of viscous flow and the viscosity. Hence, the increase of the BaO/Al 2 O 3 ratio and Li 2 O content within limits could lower the viscosity, melting temperature, break temperature and crystallization ability of mold slags, and then improve the lubrication of the slag on solidified shell. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) is a versatile and sustainable polymer used in various applications. This research explores the use of orotic acid (OA) and ethylene bis-stearamide (EBS) as nucleating agents to enhance the quiescent crystallization of PLA within the temperature range of 80 °C to 140 °C. Different blends were produced via melt processing before analyzing via DSC, XRD, and SEM. Our results show that both nucleating agents significantly accelerated the crystallization process and reduced the incubation time and the crystallization half-time. The most promising results were obtained with 1% EBS at 110 °C, achieving the fastest crystallization. The XRD analysis showed that at 80 °C, the disordered α'phase predominated, while more stable α phases formed at 110 °C and 140 °C. Combining the 1% nucleating agent and 110 °C promotes densely packed crystalline lamellae. The nucleated PLA exhibited a well-organized spherulitic morphology in agreement with the Avrami modeling of DSC data. Higher nucleating agent concentrations yielded smaller, more evenly distributed crystalline domains. Utilizing OA or EBS in PLA processing could offer enhanced properties, improved processability, and cost-efficiency, making PLA more competitive in various applications. [ABSTRACT FROM AUTHOR]

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The blends of poly(D-lactic acid) and poly(L-lactic acid) (PDLA/PLLA) produce the stereocomplex crystals (SC) with a melting temperature of ~ 250 °C, which exhibits higher crystallization rate and mechanical strength than PDLA or PLLA. The SC was also reported as an effective nucleator for PLA homochiral crystals (HC). In the PDLA/PLLA blends, the SC would develop at first in most of cases. However, the morphology of SC in the asymmetric blends were rarely reported, and the effect of the SC morphology on the subsequently crystallization of HC was not clear yet. In this study, the PDLA/PLLA blends with dissimilar weight ratios were prepared by three methods, i.e., electrostatic spinning, solution casting, and melted-cooling, and the SC with different morphologies were achieved. Then, the crystallization behavior of HC under the existence of SC was studied. Results indicated that the SC morphology exerted diverse effects on the formation of HC. The SC with fibrous and banded morphology produced by electrostatic spinning presented great limitation for the formation of HC. The SC with spherical morphology developed in the solution casting films enhanced the formation of HC. The SC with network structure produced in the melted-cooling specimens accelerated the crystallization rate of HC significantly. This investigation indicated that not only the content of SC, but also the morphology of SC would influence the crystallization behavior of HC, which would make a deep understanding for the crystallization behavior of PDLA/PLLA specimens. [ABSTRACT FROM AUTHOR]

This work presents the optimization of the crystallization behavior and reliability of Sn15Sb85 thin films by doping Sm element. The phase transition behaviors induced by thermal were investigated by in situ resistance measurement. With the addition of Sm element, Sn15Sb85 film exhibits the superior crystallization temperature (232 °C) and data conservation (172.32 °C for 10 years), larger activation energy of crystallization (4.91 eV) and crystalline resistance (∼103 Ω), which contributes to the increased thermal stability of the amorphous state and decrease in the programming energy. The Sm-doping can broaden the energy band gap from 0.55 to 1.07 eV. The amorphous Sm and Sn compositions could retard grain growth and refine grain size from 21.13 to 11.13 nm, combining with x-ray diffraction and x-ray photoelectron spectroscopy. The surface morphology of Sn15Sb85 film becomes smoother after Sm doping as determined by atomic force microscopy images, resulting in the improved interfacial reliability. Phase change memory devices based on Sm0.095(Sn15Sb85)0.905 films can successfully achieve the complete SET and RESET reversible operation process with high operating speed (200 ns) and low power consumption (1.6 × 10−10 J). The results suggest that doping the proper concentration of Sm element will be an effectual solution to adapt and optimize the crystallization properties of Sn15Sb85 phase change material. [ABSTRACT FROM AUTHOR]

Utilizing neodymium-based butadiene rubber as a baseline, this study examines the effect of eco-friendly aromatic TDAE oil, fillers, and crosslinking reactions on neodymium-based rare-earth butadiene rubber (Nd-BR) crystallization behavior. The findings suggest that TDAE oil hinders crystallization, resulting in decreased crystallization temperatures and heightened activation energies (Ea). The crystallization activation energies for 20 parts per hundreds of rubber (PHR) and 37.5 PHR oil stand at −116.8 kJ/mol and −48.1 kJ/mol, respectively, surpassing the −264.3 kJ/mol of the unadulterated rubber. Fillers act as nucleating agents, hastening crystallization, which in turn elevates crystallization temperatures and diminishes Ea. In samples containing 20 PHR and 37.5 PHR oil, the incorporation of carbon black and silica brought the Ea down to −224.9 kJ/mol and −239.1 kJ/mol, respectively. Crosslinking considerably restricts molecular motion and crystallization potential. In the examined conditions, butadiene rubber containing 37.5 PHR oil displayed no crystallization following crosslinking, albeit crystallization was discernible with filler inclusion. Simultaneously, the crystallinity level sharply declined, manifesting cold crystallization behavior. The crosslinking process elevates Ea, while the equilibrium melting point ( T m 0 ) noticeably diminishes. For instance, the T m 0 of pure Nd-BR is approximately −0.135 °C. When blended with carbon black and silica, the T m 0 values are −3.13 °C and −5.23 °C, respectively. After vulcanization, these values decrease to −21.6 °C and −10.16 °C. Evaluating the isothermal crystallization kinetics of diverse materials via the Avrami equation revealed that both the oil and crosslinking process can bring about a decrease in n values, with the Avrami index n for various samples oscillating between 1.5 and 2.5. Assessing the dynamic mechanical attributes of different specimens reveals that Nd-BR crystallization notably curtails its glass transition, marked by a modulus shift in the transition domain and a decrement in loss factor. The modulus in the rubbery state also witnesses a substantial augmentation. [ABSTRACT FROM AUTHOR]

As semi-crystalline polyester (lactic acid) (PLA) is combined with other reinforcing materials, challenges such as phase separation, environmental pollution, and manufacturing difficulties could hinder the benefits of PLA, including complete biodegradability and strong mechanical properties. In the present investigation, melt blending is utilized to establish a mixture of low- and high-molecular-weight polylactic acids (LPLA and HPLA). The crystallinity, rheology, and mechanical properties of the combination were analyzed using rotational rheometry, differential scanning calorimetry, X-ray diffraction, polarized optical microscopy, scanning electron microscopy, and universal testing equipment. The results demonstrate compatibility between LPLA and HPLA. Moreover, an increase in LPLA concentration leads to a decrease in the crystallization rate, spherulite size, fractional crystallinity, and XRD peak intensity during isothermal crystallization. LPLA acts as a diluent during isothermal crystallization, whereas HPLA functions as a nucleating agent in the non-isothermal crystallization process, promoting the growth of LPLA crystals and leading to co-crystallization. The blended system with a 5% LPLA mass fraction exhibits the highest tensile strength and enhances rheological characteristics. By effectively leveraging the relationship between various molecular weights of PLA's mechanical, rheological, and crystallization behavior, this scrutiny improves the physical and mechanical characteristics of the material, opening up new opportunities. [ABSTRACT FROM AUTHOR]

In this work, a novel α-nucleating agent (NA) for polypropylene (PP) termed APAl-3C-12Li was prepared and evaluated compared with the commercially available type NA-21. For the synthesis of the organophosphate-type NA (APAl-3C), the -OH group of the acid part of NA-21 was substituted by the isopropoxy group. The structure of APAl-3C was analyzed by spectroscopy and element analysis, the results of which were consistent with the theoretical molecular formula. APAl-3C's thermal stability was studied by differential scanning calorimetry (DSC) and thermogravimetry (TG), which showed only weak mass loss below 230 °C, meaning that it would not decompose during the processing of PP. The APAl-3C-12Li was used as a novel nucleating agent, studying its effects on crystallization, microstructure, mechanical and optical properties. Tests were performed in a PP random copolymer at different contents, in comparison to the commercial NA-21. The composite with 0.5 wt% APAl-3C-12Li has a similar crystallization temperature of 118.8 °C as with the addition of 0.5 wt% NA-21. An advantage is that the composite with the APAl-3C-12Li has a lower haze value of 9.3% than the counterpart with NA-21. This is due to the weaker polarity of APAl-3C-12Li after the introduction of methyl and better uniform dispersion in the PP matrix, resulting in stronger improvement of optical and mechanical properties. [ABSTRACT FROM AUTHOR]

The development of high-performance and low-cost composite nucleating agents has become a pioneering point in expanding the application of isotactic polypropylene (iPP). To this end, this article used a physical blending method to mix nucleating agent organic phosphate salt (LPN-9081) with inorganic fillers such as wollastonite and talc powder. Change the ratio of nucleated mineral-reinforced composition LPN-9081/wollastonite (L/WO) and LPN-9081/talc powder (L/Tac) to study their effects on the crystallization, melting behavior, and mechanical properties of iPP. And a preliminary exploration was conducted on its mechanism. The results suggest that the nucleated mineral-reinforced composition more significantly enhance the crystallization temperature, increasing it by up to 10 °C. Furthermore, it was observed that the mechanical properties of iPP were significantly improved via the synergistic effect of LPN-9081 and the inorganic fillers. In the iPP/L/WO system, the addition of the composite nucleating agent improved rigidity by 146% while maintaining toughness. Similarly, compared with iPP system, the iPP/L/Tac system has improved its rigidity by 107% and toughness by 50%. Using the nucleated mineral-reinforced compositions mentioned above can reduce industrial expenses, while increases the rigidity and toughness of iPP, expanding its potential of applications. [ABSTRACT FROM AUTHOR]

The 50 Li 2 O - x Al 2 O 3 - (50 - x) B 2 O 3 (x = 3–7 mol%) glass-ceramics were prepared by solid-state reaction method. Homogeneous glasses were obtained by water quenching, and the glass-ceramics with the LiBO 2 and Li 3 AlB 2 O 6 as main crystalline phases were prepared after the subsequent sintering process. The appropriate content of Al 2 O 3 can significantly improve the densification and crystallization of Li 2 O - Al 2 O 3 – B 2 O 3 (LAB) glasses. The fully densified glass-ceramics with 4 mol% Al 2 O 3 exhibit uniform and fine microstructure and large volume density. This glass-ceramic sintered at 650 °C for 7 h displays excellent microwave dielectric properties with ε r = 5.47, Q × f = 21814 GHz (at 13.6 GHz), and τ f = - 61.3 ppm/°C. Additionally, the LAB glass-ceramics are chemically compatible with aluminum (Al) and silver (Ag) electrodes at their sintering temperatures, which shows significant potential in ultralow temperature co-fired ceramic (ULTCC) for packaging substrate applications based on their good microwave dielectric performance and good chemical compatibility. [ABSTRACT FROM AUTHOR]

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Promoting molten calcium–magnesium–alumina–silicate (CMAS) crystallization can highly reduce the melt penetration into thermal barrier coatings (TBCs), which alleviates its corrosion to TBCs. In marine environments, many salts are coupled with CMAS. In this study, we investigated the crystallization behavior of CMAS + NaCl/NaSO4, and pointed out its influence on the corrosion behavior of TBCs. At 1200 ℃, CMAS + NaCl was crystalized into CaMgSi2O6, CaSiO3 and CaAl2Si2O8, while the crystallization products of CMAS + NaSO4 depended on NaSO4 content, i.e., 4 wt.% and 10 wt.% NaSO4 addition leading to CaAl2Si2O8 and Ca2Al(AlSiO7) phases, respectively, in addition to CaMgSi2O6 and CaSiO3. At 1100 ℃, CMAS + NaSO4 crystalized, while CMAS + NaCl had no crystallization. At lower temperatures, both NaCl and NaSO4 additions could suppress CMAS crystallization. It reveals that CMAS coupled with molten salt is hard to crystallize, which is detrimental to corrosion protection.

Nowadays, Y 2 O 3 –Al 2 O 3 –SiO 2 (YAS) glass joining is considered to be a promising scheme for nuclear-grade continuous silicon carbide (SiC) fiber reinforced SiC matrix composites (SiC/SiC). CaO has great potential for nuclear applications since it has low reactivity and low decay rate under nuclear irradiation. In this paper, the effect of CaO doping on the structure, thermophysical properties, and crystallization behavior of YAS glass was systematically studied. As the CaO doping content increased, the number of bridge oxygens and the viscosity at high temperatures reduced gradually. After heat treatment at 1400 °C, the main phases in YAS glass were β-Y 2 Si 2 O 7 , mullite, and SiO 2 (coexistence of crystalline and glass phases), while that with 3.0% CaO doping turned into a single glassy phase under the same treatment conditions. Moreover, a structural model and the modification mechanism were proposed, which provided a theoretical basis for the subsequent component design and optimization. [ABSTRACT FROM AUTHOR]

Blending octene random copolymer (ORC) with other polymers is a promising approach to improving ORC mechanical properties, such as tensile strength and elongation. In this study, octene block copolymer (OBC) with lower density than ORC and high-density polyethylene (HDPE) were used to blend with ORC. The effect of both OBC and HDPE on ORC was analyzed using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and small-angle X-ray scattering (SAXS). For ORC/OBC blends, a small amount of OBC can improve the crystallization ability of ORC. Meanwhile, for ORC/HDPE blends, the crystallization ability of ORC was significantly suppressed, attributed to good compatibility between ORC and HDPE as indicated by the homogeneous morphology and the disappearance of the α transition peak of ORC in ORC/HDPE blends. Therefore, the tensile strength and elongation of ORC/HDPE blends are significantly higher than those of ORC/OBC blends. For ORC/OBC/HDPE ternary blends, we found that when ORC:OBC:HDPE are at a ratio of 70:15:15, cocrystallization is achieved. Although HDPE improves the compatibility of ORC and OBC, the three-phase structure of the ternary blends can be observed through SAXS when HDPE and OBC exceed 30 wt%. Blending HDPE and OBC (≤30 wt%) could improve the mechanical property of ORC. [ABSTRACT FROM AUTHOR]

The photovoltaic, luminescence, and detector fields have witnessed the robust application prospects of solution‐processed halide perovskites. Deep insights into solution can pave the way toward the precise crystallization control of halide perovskites for giving full play to the advantages of those materials. Herein, the dissolution behavior of formamidinium lead iodide (FAPbI3) together with lead iodide in amide solvents with regulated coordination ability at increasing temperature and under different molar ratio between formamidinium iodide (FAI) and PbI2 is studied. The solvent coordination ability, temperature, and FAI/PbI2 molar ratio demonstrate equivalent influence on the dissolution, and increasing those factors tends to increase the solubility first and decrease it then for Pb compounds. It is proposed that there are interchangeable Pb solute forms including solvent‐containing lead complexes and solvated lead halide fragments in solution and the interconversion of both solutes driven by the above factors brings the solubility change. The modulated dissolution affects the crystallization behaviors of FAPbI3 when preparing single crystals, nanocrystal dispersions, and thin films, and allows for regulated crystallinity in printable mesoscopic solar cells which demonstrate a power conversion efficiency of 18.40%. [ABSTRACT FROM AUTHOR]

Poly(butylene adipate‐co‐terephthalate) (PBAT), a biodegradable copolyester, was used as the polymer matrix to prepare nanocomposites with multiwalled carbon nanotubes (MWCNT) by melt‐mixing followed by hot‐pressing. The PBAT/MWCNT nanocomposites were exposed to electron beam (EB) irradiation, and thermal stability, melting and crystallization behavior of irradiated and unirradiated nanocomposites were comparatively investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), respectively. TGA results reveal increased thermal stability (up to 17°C) and maximum degradation temperature (Tmax) (up to 15°C) of PBAT/MWCNT nanocomposites, attributed to the high thermal stability of MWCNT and good MWCNT–PBAT interfacial interactions. However, the activation energy for thermal degradation (Ea) decreased with the presence of MWCNT in comparison to neat PBAT regardless of the MWCNT concentration. Both the thermal stability and Tmax of irradiated nanocomposites decreased by 3°C despite the crosslinking which can be attributed to successive minor irradiation‐induced polymer degradation, while Ea remained unchanged. Declined melting temperature (Tm), enthalpy of crystallization, enthalpy of melting and crystallinity of nanocomposites with the presence of MWCNT suggest the formation of less perfect crystals. Meanwhile, their increased glass transition temperature (Tg) and crystallization temperature (Tc) are due to the increased rigidity of PBAT chains and a reduced crystallization process in the presence of MWCNT, respectively. Similarly, reduced crystallinity and values of Tm and Tc of EB‐irradiated nanocomposites by 4.1%, 9.6%, and 7.5%, respectively, signifying the presence of PBAT‐crosslinks resulting in crystal defects. [ABSTRACT FROM AUTHOR]

In this work, the Fe3O4-carbon black filler was obtained from an in-situ coprecipitation method followed by the modification of the heptadecafluorodecyltrimethoxysilane and the Fe3O4-carbon black/poly(vinylidene fluoride) (PVDF) composites with enhanced properties were prepared by a simple solution blending-water precipitating method. The Fe3O4-carbon black distributed well in the PVDF matrix, which was confirmed by the SEM. According to the results of FTIR and WAXD, a lot of useful polar crystalline phases of PVDF formed in the Fe3O4-carbon black/PVDF composites. The electrically conductive ability, the dielectric permittivity, the dielectric loss factor, and the magnetic saturation value of the Fe3O4-carbon black/PVDF composite increased with the increasing loading amount of Fe3O4-carbon black filler. Especially, when the Fe3O4-carbon black was 5 wt.%, the dielectric permittivity of Fe3O4-carbon black/PVDF composite reached as high as 23.5 at 1000 Hz with a relatively low dielectric loss factor value of 0.38 and a magnetic saturation value of 0.64 emu/g. [ABSTRACT FROM AUTHOR]

А series of rapidly solidified alloys (Al-Cu-Mg)100-xNix, x = 0, 1, 2, 3 at. % were obtained by the Chill Block Melt Spinning (CBMS). XRD and TEM analyzes showed a completely amorphous structure of the alloys. The glass transition temperature (Tg), crystallization temperature (Tx), solidus Ts and melting temperatures (liquidus) Tl were determined by DSC analyses. It was found that Tg and Tx increased with increasing the nickel content in the alloys. The reduced glass transition temperature (Trg), temperature difference ΔTx and the Hruby criterion KH were calculated. It was found that the alloy (Al-Cu-Mg)97Ni3 is most thermally stable. Crystalline analogues of the amorphous alloys were obtained by annealing of melt-spun ribbons. The type and size of the separated crystal phases were determined by XRD analysis and a tendency for size diminishing with the nickel content increase was established. [ABSTRACT FROM AUTHOR]

This work studied the influence of thermomechanical treatment on the mechanical properties, structure, and crystallization of the Zr65.5Ni16Cu8.5Al10 metallic glass alloy. It established that thermomechanical treatment significantly affects the mechanical properties of the alloy while maintaining its amorphous structure due to the formation of regions of chemical inhomogeneity in the amorphous matrix. In addition, shear deformation affects the initial crystallization of the alloy. As a result, there is a transition from one-stage crystallization to two-stage crystallization with a strain increase. [ABSTRACT FROM AUTHOR]

Amorphous alloys show interesting mechanical properties as well as unique physical and chemical properties due to their atomic stacking structure. However, when partial crystallization occurs in amorphous alloys, it can impact the properties of the original amorphous alloy. To study the crystallization phenomenon in the Zr-based amorphous alloy, a three-dimensional Zr-based amorphous alloy atomic-stacking model was established by molecular dynamics simulations, and the atomic structure evolution of the Zr-Cu amorphous system after partial crystallization was analyzed by the radial distribution function g(r), HA bond index and Voronoi polyhedron. The results showed that adding more copper (Cu) atoms to the Zr-Cu amorphous system greatly improves its stability at high temperatures. The atomic diffusion was analyzed by root-mean-square displacement of atoms (MSD); as the temperature rose, the MSD of atoms also increased, suggesting that the crystallization of the amorphous material occurs due to the short-range diffusion of atoms. The analysis of the mechanism of the high-temperature action time on the Zr80Cu20 amorphous alloy showed that the crystallization phase precipitation rate of the amorphous alloy gradually increases with time, but it does not change linearly. [ABSTRACT FROM AUTHOR]

This study evaluated various mechanical responses that evolved as a function of gauge length for PGCL sutures. Gauge length dependency is important to be studied as it directly reflects the possible complications related to suture failure and inadequacy of mechanical properties, which could happen due to inappropriate suture lengths used in incision closure. The results show that the gauge length caused differences in monotonic and cyclic responses of the PGCL samples. However, the stress relaxation response is unaffected by the gauge length. In monotonic responses, most of the mechanical parameters, including elongation at break, load at break, ultimate tensile strength as well as initial modulus, improve with increasing gauge length. The overall stiffness and strain at break decrease as the gauge length increases. Both stress-softening and hysteresis loops are observed in all PGCL samples with varying gauge lengths. As the gauge length increases, the permanent set decreases, whereas the maximum stress level and hysteresis increase. Concerning crystallization behavior, the degree of crystallinity, lattice strain, and crystallite size are altered by the gauge length. As the gauge length increases, the lattice strain decreases, and the crystallite size decreases. [ABSTRACT FROM AUTHOR]

The phase morphology, crystallization behavior, and mechanical properties of polylactide (PLA) modified by polyamide elastomer (PAE) have been systematically investigated. SEM images showed that PAE was homogeneously dispersed in the PLA matrix forming a sea-island morphology. The dimension of PAE domains increased slightly with its content and still remained smaller than 3 μm even at 40 wt% due to the partial compatibility of PLA and PAE. PAE had some nucleation effect on PLA and promoted the crystallization of PLA to a certain extent. The crystallization kinetics and crystalline morphology, especially the nucleation and growth of PLA crystals, were compared in detail between pure PLA and PLA/PAE blends. The elongation at break and impact strength of PLA were considerably improved by PAE. The sample PAE20 exhibited the best rigidity-toughness balance showing ductile failure. The toughening mechanism was proposed based on the deformation of the impact fracture surfaces. [ABSTRACT FROM AUTHOR]

The matrix material used in this paper was low-density polyethene (LDPE), and the added particles selected were silicon oxide (SiO2) particles and montmorillonite (MMT) particles. The sizes of the SiO2 particles were 1 µm, 30 nm, and 100 nm, respectively; three kinds of SiO2/MMT/LDPE multi-component composites were prepared based on MMT/LDPE composites doped with MMT particles. The effect of the SiO2 particle size on the crystallization behavior and space charge properties of SiO2/MMT/LDPE composites was studied. The crystalline behaviors and crystallinity of the materials were analyzed. At the same time, the changes in the relative dielectric constant εr and loss factor tanδ for each material with the influence of frequency were studied, and the space charge accumulation, residual characteristics, and apparent charge mobility of each material were explored. The results show that the smaller the size of the added particles, the smaller the grain size and the clearer the grain outline for the multi-composite material. After adding 30 nm SiO2 particles, the crystallinity of the material increases significantly. The microstructure formed by the addition of 100 nm SiO2 particles effectively restricts molecular chain movement and makes it difficult to establish the polarization of the composite. The incorporation of large-size particles can reduce the proportion of the crystalline structure for the material as a whole, resulting in the formation of a new structure to promote charge transfer. Among the three kinds of SiO2 particles, the addition of 30 nm SiO2 particles can effectively suppress the space charge, and the composite material has the lowest residual space charge after depolarization. The addition of 100 nm SiO2 particles can cause the accumulation of many homopolar charges near the anode.

The xerogels based on the aqueous solutions of urea in potassium silicate liquid glass (PSLG) were produced by CO2 bubbling and investigated. The structure and chemical composition of the obtained materials were analyzed. Using the SEM, XRD, IR-FT, DSC, and low energy local EDS analysis, it was recognized that the dried gels (xerogels) contained three forms of urea: oval crystals of regular shape appeared onto the surface of xerogel particles; fibrous crystals were located in the silicate matrix; and molecules/ions were incorporated into the silicate matrix. It was shown that an increase in [(NH2)2CO] in the gel-forming system promoted increased contents in crystalline forms of urea as well as the diameter of the fiber-shaped urea crystals. A rate of the urea release in water from the granulated xerogels containing 5.8, 12.6, and 17.9 wt.% of urea was determined by the photometric method. It was determined that the obtained urea-containing xerogels were characterized with a slow release of urea, which continued up to 120 days, and could be used as controlled release fertilizers containing useful nutrients (N, K). [ABSTRACT FROM AUTHOR]

Blending of poly(levorotatory-lactic acid) (PLLA) and poly(dextrorotatory-lactic acid) (PDLA) produces the stereocomplex crystallites (PLA SC), which present higher melting temperature and mechanical properties than that of neat PLLA or PDLA. However, in the PLLA/PDLA blends with higher molecular weights, the phase separation occurs and the SC exhibits weak memory after melting, which lead to a small amount of SC together with a large amount of homochiral crystallites (HC) develop during crystallization from the melt. In this study, a small content of graphite oxide was blended with PLLA and PDLA to form ternary blends, and it was exciting to find that the formation of SC was enhanced gradually with the content of graphite oxide. The SC exclusively developed when 2 wt% graphite oxide was incorporated into the PLLA/PDLA, and the crystallinity with ∼50% was received even during fast cooling from the melt (−50 °C/min). The acceleration formation of SC was speculated due to the interaction between PLA molecular chains and the hydroxyl groups on the surface of graphite oxide and the obstruction of proliferation of graphite oxide. [ABSTRACT FROM AUTHOR]