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The mechanical properties of natural rubber (NR) vulcanizate depend strongly on several factors, i.e., vulcanization systems and crosslink density. These two parameters are originally from the formulation design of the vulcanizate. To focus more on such details, influences of three different vulcanization systems (sulfur, peroxide, and phenolic resin) with variations in their crosslink densities were studied by focusing on the change of curing properties, crosslink densities, mechanical properties and network structures of the NR vulcanizates. The crosslink density of various vulcanization systems increased with increasing curing promotors, as revealed by temperature scanning stress relaxation measurement. The tensile modulus at 100% strain increased with increasing crosslink density in all systems but the tensile strength varied with the vulcanization systems and degree of crosslink density. At the same crosslink level, the greatest tensile strength was obtained when the sulfur was used as a crosslinker, which was 100% greater than those obtained from peroxide and 200% over phenolic systems. In comparison to the phenolic resin system, sulfur and peroxide crosslink systems had a more uniform distribution of the crosslink network structure. The size of the network structure was found to be independent of the tensile strength. The peroxide system had the most uniform distribution of the crosslink network structure.

In this study, the relationships between the structure of unvulcanized rubber and vulcanizate properties were investigated for the three natural rubber clones: RRIT251, PB235, and RRIM600. The highest tensile properties of rubber vulcanizates were achieved from the PB235 clone whereas the RRIM600 showed the lowest. The PB235 contained the largest average molecular weight (Mw) with the narrowest molecular mass distribution (MWD), whereas the least Mw was for RRIM600 with the broadest MWD. The highest protein contents were noticed in RRIM600 where the highest gel formation was found. In contrast, the PB235 showed the smallest amount of proteins and gel contents. Based on this finding, the results clearly suggested that the Mw represented as a key factor controlling the mechanical properties of vulcanizates. This was because the higher average Mw provide the greater active sites available for crosslinking reaction, while the protein content governed the gel formation in the unvulcanized rubber.

Biocomposites of poly(lactic acid) (PLA) and pectin, which are low-cost organic materials, were prepared using an internal mixing machine in various pectin contents, i.e., 2, 4, 6 and 8% w/w. When pectin was added as a nucleating agent, the mechanical properties of the biocomposites, such as tensile and impact testing, were considerably improved, particularly following the annealing process. In addition, the PLA–pectin annealed at 4% w/w showed the highest strength and thermal stability. This can be explained by the fact that PLA containing 4% pectin by weight had the best dispersion, as indicated by scanning electron microscopy (SEM) and synchrotron-based 2D chemical mapping FT-IR. Moreover, pectin not only serves as a reinforcing material to improve mechanical characteristics but also aids in the crystallization of PLA, which was confirmed by in situ synchrotron-based wide-angle X-ray scattering (SR-WAXS). The crystallization rate and crystallinity were maximum at 8% w/w pectin addition according to the SR-WAXS results. This shows that pectin dispersion is the most important factor in determining the mechanical and thermal properties of biocomposites.

A high degree of spin polarization in half-metallic double perovskites is a prerequisite for several applications in spintronics, which depends crucially on the cationic order of the systems. This paper reports a study on tailoring the structure and morphology of nano-sized Sr2Fe1-xZnxMoO6 (x = 0.05, 0.1, 0.15) materials to improve their spin polarization. The combined analysis of synchrotron X-ray diffraction and magnetization data shows that Zn replaces Fe in the B sites. Although the majority of particles have lateral dimensions in the range 30–60 nm as observed by scanning electron microscope, the samples with x = 0.1 and 0.15 show finite-size effects with superparamagnetism below room temperature and a reduced Curie temperature (from 410 K for x = 0.05–390 K for x = 0.15). The results are due to the formation of networks of insulating Mo–O–Zn–O–Mo linkages and anti-phase boundaries, which divide the particles into smaller domains with a mean diameter of ∼11 nm as determined via a Langevin fit. The almost perfectly ordered structure in the nanodomains is responsible for a high magnetoresistance ratio. A value of -42% at 5 K in 50 kOe is recorded for the sample x = 0.15. Via fitting the magnetoresistance curve using the Inoue-Mekagawa theory, the spin polarization of 99% is determined.

Structural evolution of impact-resistant polypropylene copolymers (IPCs), having different compositions of segmental ethylene–propylene (sEP) copolymers, under tensile deformation was investigated ...

The performance of natural rubber (NR) relies heavily on the microstructural changes during deformation. This has brought to significant change in the stress response of NR. Besides, the stretching rate may also affect the stress response of NR. In this study, effects of stretching rate on tensile deformation and strain-induced crystallization of crosslinked NR were investigated. Results indicated that increasing the strain rate has increased the stress at given strain where the onset of strain-induced crystallization was shifted to a lower strain. The crystallinity of the crosslinked NR was shown to be higher at a high stretching rate and it corresponded well with the tensile response. The results clearly confirm that chain orientation and crystallization became stronger with increasing deformation rate. The study also suggests that the deformation could improve distribution of crosslinked network structures.

Determining structure of highly flexible protein with multiple conformations can be challenging. This paper aims to combine molecular dynamics (MD) and small angle X-ray diffraction (SAX) techniques as a solution to overcome issues related to protein conformation in hardly crystallized protein. Based on prior studies, a cold-active lipase AMS8 was simulated in solvents showing stability in its N-terminal and high flexibility in its C-terminal. However, MD in its own algorithm could not explain the basis of macromolecule conformational transitions or changes related to protein through folding. Hence, by combining SAXS with MD, it is possible to understand the structure of flexible AMS8 lipase in natural space. Based on the findings, SAXS ab-initio model of AMS8 lipase was identified as a monomeric protein in which the optimized model of cold-active lipase AMS8 derived from SAXS data was found to be aligned with AMS8 homology model under series of MD timeframe.

The fibrillation mechanism of insulin in acid solution has been studied by small angle X-ray scattering (SAXS). It was observed that insulin monomer unfolded in both conditions. Furthermore, in zinc free solution, insulin tend to aggregate on heating start in the first 5 min. The fibrillation through aggregation process continues until 30 min on heating. The similar phenomenon occurs in the presence of zinc ions. The SAXS data suggest that the presence of zinc ions prevent the long cylindrical fibril at the beginning of heating. However, after 20 min heating, the large cylindrical fibril of insulin formed in both conditions.

Sn-substituted yttrium iron garnet samples, Y3Fe5-xSnxO12 (x = 0–0.1, step 0.02) were prepared using a citrate sol–gel method and followed by a sintering process. Synchrotron X-ray diffraction (SXRD), X-ray absorption near edge structure (XANES), scanning electron microscope (SEM) and Fourier infrared spectroscopy (FTIR) measurements were used to investigate the structure parameters, valence state of Fe, oxygen vacancies and lattice distortion in the samples. The magnetic properties of the samples were measured with the SQUID and VSM equipments. The Sn substitution and oxygen vacancies cause the transformation of Fe3+ to Fe2+ which leads to the decrease of Curie temperature and slight increase of saturation magnetization. Temperature dependence of the resistivity in the range of 300–573 K was investigated to elucidate the conduction mechanism in the samples. The resistivity of the sol-gel derived samples was found to be nine orders of magnitudes lower than the value for the bulk sample prepared by flux-grown method. The effects of Fe2+ centers, lattice dislocation, porosity and grain boundary on the resistivity are discussed. This study indicates that Sn-substituted yttrium iron garnets are good candidates for sensor elements which operate based on electrical signals.

This paper reports the synthesis of a series of nanosized titanomagnetite particles from iron sand in the system of TixFe3-xO4 (x ranges from 0 to 0.5). The titanomagnetite particles were prepared by the coprecipitation method. It was found that the samples crystallized in spinel structure without any impurities. In general, the higher composition of titanium tended to increase the lattice parameters (from 8.3689 to 8.3715 A as × increases) originated from the titanium ions with the bigger ionic radii than those Fe ions substitute for magnetite. The functional groups of metal–oxygen bonding from tetrahedral and octahedral sites could be determined to form infrared band at 425–475 cm−1 and 630–475 cm−1. Moreover, the titanium substitution into magnetite to form titanomagnetite structures did not change their optical band gap of 2.1 eV significantly. The small-angle scattering investigation presented that the samples constructed a 3-dimensional structure with a fractal dimension from 2.7 to 3.0 as × increases.

Recently, monolaurin (ML) has received great interest due to its possible use as an alternative antifungal. However, the limited water solubility of ML is still a major obstacle to its formulation and application. Gel-like microemulsions are one of the promising carriers for low-water-solubility substances due to both the advantages of gels and microemulsions and may be applied for ML. In this study, ML was incorporated into gel-like microemulsions and evaluated for its physicochemical and antifungal properties. The results indicated that the properties of gel-like microemulsion changed after the incorporation of ML, suggesting that ML can induce the transition of internal structure. When simulating the oral cavity environment, changes in the microstructure were observed and depended on the times of dilution. The lamellar structure was formed at 1.5-2 times dilution. However, this structure was disrupted after dilution five times or more. The structural change following dilution was associated with the release profiles. After contacting the formulations with the medium, ML was promptly released, with the majority of ML being released within 2 h. Regarding the antifungal assay, the ML-loaded gel-like microemulsions decreased the survival of Candida albicans within 3 h, although ML was immediately released, suggesting that the ML-loaded in oil droplets required time to permeate through the fungal cell wall. Additionally, the gel-like microemulsions possessed acceptable stability after the temperature cycling test. Therefore, gel-like microemulsions can be a possible carrier for ML loading, and ML-loaded gel-like microemulsions may be applied as an alternative antifungal preparation in the future. Graphical abstract.

This study is the first report on the preparation of mesoporous carbon/silica (MCS) nanocomposites with tunable mesoporosity and hydrophobicity using natural rubber (NR) as a renewable and cheap carbon source. A series of mesoporous nanocomposites based on NR and hexagonal mesoporous silica (HMS) were prepared via an in situ sol–gel process and used as precursors; then, they were converted into MCS materials by controlled carbonization. The NR/HMS precursors exhibited a high dispersion of rubber phase incorporated into the mesostructured silica framework as confirmed by small-angle X-ray scattering and high-resolution transmission electron microscopy. An increase in the carbonization temperature up to 700 °C resulted in MCS nanocomposites with a well-ordered mesostructure and uniform framework-confined wormhole-like channels. The NR/HMS nanocomposites possessed high specific surface area (500–675 m2 g−1) and large pore volume (1.14–1.44 cm3 g−1). The carbon content of MCS (3.0–16.1 wt%) was increased with an increase in the H2SO4 concentration. Raman spectroscopy and X-ray photoelectron spectroscopy revealed the high dispersion of graphene oxide-like carbonaceous moieties in MCS materials; the type and amount of oxygen-containing groups in obtained MCS materials were determined by H2SO4 concentration. The enhanced hydrophobicity of MCS nanocomposites was related to the carbon content and the depletion of surface silanol groups, as confirmed by the water sorption measurement. The study on the controlled release of diclofenac in simulated gastrointestinal environment suggests a potential application of MCS materials as drug carriers.

A reroute process of Hummers’ method was carried out to reduce some steps in the synthesis of highly exfoliated graphene oxide (HEGO). Using pure KMnO4 and NaNO3 in concentrated H2SO4, HEGO was suc...

The effect of mastication time in an internal mixer on the physical properties and microstructure of natural rubber (NR) was studied. The Mooney viscosity, plasticity, and complex viscosity reduced with increases in the mastication time due to the molecular breakdown of the rubber. The microstructural changes in the NR were studied using small-angle X-ray scattering. The results revealed that a reduction in the physical properties correlated with the structural changes, which occurred due to mastication. Increases in mastication time affected the distribution and size of the nonrubber component aggregations and the uniformity of the molecular structure of the NR.

Indium-substituted yttrium iron garnet samples, Y3Fe5−xInxO12 (x = 0–0.7, step 0.1), were prepared using a citrate solgel method. Synchrotron X-ray diffraction (SXRD) measurements combined with the Rietveld refinement technique were used to investigate the crystallization, structure parameters and lattice distortion in the samples. Magnetization and Curie temperature of the samples were measured with the SQUID and VSM equipments. The non-magnetic indium ions were found to reside at the octahedral sites, leading to an increase of the total magnetization and a decrease in the Curie temperature. Molecular field coefficients Naa, Ndd and Nad were determined by fitting the experimental thermomagnetization curves in the framework of a two-sublattice ferrimagnetic model. The stiffness constant of the spin waves, D, in these samples was calculated based on the exchange interaction constants, Jij, and its temperature dependence was derived for the sublattice magetizations. The calculated results for D(T) are in good agreement with the experimentally measured data and are significantly large around room temperature.

This work is aimed to identify the structure of the graphene-based particles (GPs) from old coconut shell as the raw material after the mechanical exfoliation processes. The burnt coconut shell was at first heated at 400 °C for 5 h in ambient air. The sample was then stirred in an acid solution (HCl) and then continued by ultrasonication and centrifugation. The exfoliated GPs were characterized by x-ray diffraction (XRD), particle size analyzer (PSA), Fourier-transform infrared spectroscopy (FTIR), scanning and transmission electron microscopy (SEM and TEM, respectively), atomic force microscopy (AFM), Raman spectroscopy, and synchrotron wide and small angle x-ray scattering (WAXS and SAXS, respectively). The XRD and WAXS analyses show Bragg peaks corresponding to a pure phase of reduced graphene oxide (rGO). PSA, SEM/TEM, AFM, and Raman analyses show that the use of HCl-assist in the solution during the exfoliation process has successfully reduced particle size of the obtained GPs. SAXS pattern of the exfoliated GPs using the assist of HCl, confirmed by TEM and AFM images, results in the specific particle sizes of between 1.42 and 4.99 nm. The present mechanical exfoliation technique has successfully been applied to obtain several nanometers of GPs and provides an alternative of simple synthesis of biomass – based graphene products.

Ethanol-treated starch (ETS) shows potentiality to be used for binder of pharmaceutical tablets. This study was aimed to evaluate the mechanical strength, structural and hydration properties of ETS tablets and ETS tablets containing lauric acid and ascorbic acid and their release behavior. ETS was prepared from cassava starch at the temperatures of 80, 90, and 100 °C. The active compounds were entrapped within the ETS tablets by two methods, including dry mixing and ethanol solubilisation. The results indicated that ETS tablets from temperatures of 80 °C showed granular shapes, had high friability and low crushing strength indexes, and dispersed and released active ingredients rapidly upon contact with water. Meanwhile, ETS tablets from temperatures of 90 and 100 °C exhibited non-granular particles, had low friability and high crushing strength indexes. Upon hydration, the tablets of non-granular ETS containing lauric acid eroded gradually and released active ingredients during tablet's erosion, meanwhile ascorbic acid diffused out gradually from the swelled tablets.

O rdered pores structure analysis of mesoporous silica material s using a template of poly(ethylene oxyde)-poly(propylene oxide)-poly(ethylene oxide), PEO-PPO-PEO, triblock copolymer or Pluronics in numerous synthesis conditions has been conducted . Two different length of hydrophilic chain of Pluronics, i.e., P123 (EO 20 PO 70 EO 20 ) and F127 (EO 106 PO 70 EO 106 ), produced two different fine pore structures, which were basically hexagonal and cubic. A highly ordered pore structure, confirming with many Bragg peaks, was clearly obtained with the lattice parameters in nanometer scale from analyzing the synchrotron s mall a ngle X-ray scattering (SAXS) data . Meanwhile, the surface are a and pores size of mesoporous silica determined by nitrogen absorption clearly support the analysis of SAXS data, presenting a complete information of pore order characteristics. This paper shows how the synthesis parameters, such as length of hydrophilic chains, silica precursor concentration, Al:Si ratio and synthesis methods, are related to the structure and order of the pores formed. The SAXS patterns show that the pore order increases with increasing concentration of sodium silicate and decreases with longer sonication time. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif"; mso-ansi-language:EN-US; mso-fareast-language:EN-US;}

Binary polymeric mixtures containing pluronic F127 (PF) and methylcellulose were prepared to generate new thermosensitive matrices. The small-angle X-ray scattering (SAXS) behavior of PF/MC blends was investigated in relation to the temperature-dependent phase transition and rheological characteristic. Although 11% w/w PF (11PF) cannot form gel, the test tube tilting method and rheological analysis showed that the incorporation of 4% w/w methylcellulose (MC) into 11PF (11PF/MC) enabled the system to form gel upon heating. In addition, adding MC lowered the gelation temperature of 17% w/w PF (17PF). The ordered structure of these gels exhibited a face-centered cubic phase at intermediate temperature above the gelation temperature; the steep upturn of the SAXS curves was observed in the small scattering vector range at high temperatures (55–70 °C). The presence of MC might cause an MC-assisted interconnected network of micelles. At high temperatures, the gelation possibly involved MC-assisted intermicellar organization of PF as well as the gel network of MC. Etidronate sodium was incorporated into the matrices, and the drug did not significantly affect the thermosensitive gelation and the ordered structure of the polymeric systems. Furthermore, this study indicated that 11PF/MC was sol at 25 °C and became gel at body temperature of 37 °C. Therefore, blending PF with MC is a potential strategy for tailoring the thermosensitive performance of the in situ gelling preparation for drug delivery.

The effects of multicycle ultrasound-assisted ice recrystallization (US+IR) combined with amyloglucosidase (AMG) or maltogenic α-amylase (MA) catalyzed hydrolysis on structure were investigated. Scanning electron microscopy (SEM) showed that the US+IR produced shallow indentations and grooves on the exterior of granules while the combination US+IR and enzyme hydrolysis created additional pores on starch granules. MA displayed a higher number of pores than AMG. The highest values of specific surface area (SBET) and the total pore volume were obtained for US+IR→MA (1.96 m2 g−1 and 7.26 × 10−3 cm3 g−1, respectively). The US+IR treatment significantly decreased the relative crystallinity, amylose content and swelling capacity. Those parameters were further efficiently decreased following enzymatic hydrolysis. The combined treatments generated products with higher initial gelatinization temperature (Ti) compared to the corresponding controls. The US+IR increased the digestion rate constant (k-value) compared to native starch. However, the combined treatment, US+IR→AMG, significantly decreased the k-value from 2.97 × 10−3 to 2.50 × 10−3 min−1 compared to its control. Our study demonstrates that US+IR treatment in combination with enzyme hydrolysis is a useful method to produce specifically functionalized porous rice starch that can be used as e.g. absorbents and for further chemical modifications.

Hydroxyapatite, which has been widely used in the medical field in the last couple of years, is a superior biomaterial due to its biocompatibility and nontoxicity. Hydroxyapatite requires highly magnetic materials to perform maximally in specific medical fields. In this study, hydroxyapatite/ magnetite composites mainly composed of limestone and natural iron sand were synthesized through a coprecipitation method, and composites having different hydroxyapatite-to-magnetite mass ratios were compared. The crystal structure, particle size, fractal dimension, morphology, functional group, and energy gap were characterized using X-ray diffraction (XRD), synchrotron X-ray scattering (SAXS), scanning electron microscopy (SEM), Fourier-transform infrared (FTIR) spectroscopy, and ultraviolent-visible (UV-Vis) spectroscopy. The research results showed that the hydroxyapatite and magnetite phases had a hexagonal structure and cubic structure, respectively. In general, from the FTIR data analysis, the hydroxyapatite and magnetite particles were identified from the functional groups of phosphate, iron-oxygen, carbonate, and hydroxyl. Moreover, depending on particle size, the samples consisting of 3.7-nm primary particles formed a cluster with a massive three-dimensional structure. Meanwhile, the energy gap showed various values ranging between 3.25 and 3.86 eV.

The structural characteristics of polymorphic raw material combinations of silica-zirconia powder systems were investigated through X-ray diffraction (XRD), Wide-angle X-ray scattering (WAXS), Fourier transform infrared (FTIR), and X-ray absorption near edge structure (XANES). Stoichiometric mixtures (1:1 mol% ratio) of silica (SiO2: amorphous and cristobalite) and zirconia (ZrO2: amorphous and tetragonal zirconia) were prepared with the addition of polyvinyl alcohol (PVA) and a ball-mill mechanical activation of 5 h, followed by calcination at 1000 and 1200 °C. The identified phases of the calcined powders were a combination of zircon, zirconia, and cristobalite. Quantitative phase analyses of the XRD and WAXS data based on the Rietveld method revealed that the amorphous-amorphous (AA) mixture contained a higher zircon composition than the others, ca 93 mol%, at a calcination temperature as low as 1000 °C. Rietveld analysis of the WAXS data was in good agreement with that of the XRD data. The PVA and ball-mill mechanical activation simultaneously enhanced the solid-state reaction. The peaks of IR absorption associated with zircon were observed at wavenumbers around 435, 615, and 900 cm−1. The IR absorption peak observed at around 1000 cm−1 indicated silica-rich content in the AT1000 and CA1000 samples. A Si K-edge XANES analysis indicated a structural distortion around Si in the zircon-containing samples as compared to the silica, resulting in an “extra” lower-energy peak. The ratio between the absorption intensities of the “extra” and the highest peaks, in general, confirmed the phase composition of zircon in the samples.

Nowadays, the application of nano-sized anatase titanium dioxide particles becomes one of the essential research focuses by many experts, especially for biomedical applications. In this work, we report the utilization of coprecipitation route in preparing nano-sized anatase titanium dioxide as an antifungal agent. The data analysis for the XRD data of the titanium dioxide particles showed that the sample crystallized with anatase structure and sized in the nanometric size of 13.30 nm. The particle size obtained from Scherrer’s analysis of the XRD data was quite similar to the particle size obtained from electron microscopy investigation. Furthermore, the small-angle scattering data presented that the anatase titanium dioxide constructed a 3-dimensional structure with a compact structure originating from the fractal dimension value of approximately 3. The functional groups of the nano-sized anatase titanium dioxide were traced in the wavelength range of 500-1500 cm-1 showing the presence of Ti-O bonding. Interestingly, the prepared sample in this experiment exhibited an excellent performance as an antifungal agent represented by inhibition zone diameter of 3.59 mm.

Heating ethanol-treated starch (ETS) is the simplest method to produce granular cold-water swelling starch. Structural transformations of ethanol-treated maize and potato starch (ETMS and ETPS) at the crystalline, lamellae and granular structural levels during heating were investigated through in situ wide- and small-angle X-ray scattering (WAXS and SAXS) combined with light microscopy (LM). The result of in situ WAXS indicated that the native crystalline structure was slowly disrupted up to 82 and 60 °C for ETMS and ETPS, respectively. The initial temperature for the formation of a V-type crystalline structure of ETMS was observed to be 86 °C. The result of paracrystalline analysis suggested that the crystalline lamellae of ETS realigned toward a more ordered register when heated to 80 °C and 70 °C for ETMS and ETPS, respectively. The granular forms of ETMS and ETPS were still preserved at 100 °C, although the characteristic of Maltese cross was not observed. A model was proposed to elucidate transformations of ETS at the three structural levels of starch during heating.

The titanium dioxide photocatalysts modified with nitrogen (N–TiO2) were synthesized via hydrothermal method by using urea (NH2CONH2) as a nitrogen source with various concentrations of dopant. The characterizations of cooperated N–TiO2 were examined by many techniques. The performance of the synthesized N–TiO2 catalysts was evaluated by using the decomposition of ciprofloxacin under UV light irradiation. Additionally, the OH radical production was also estimated. The results revealed that the influence of different concentrations of nitrogen dopant was significant on the physicochemical and structural properties. The surface morphology exhibited the nanorice grain particles in all samples. The trend of particles size and pore diameter decreased, whereas BET surface area slightly increased with increasing of nitrogen contents. The WAXS profiles demonstrated that the photocatalysts displayed the high purity of the anatase crystalline phase and delayed the phase transformation from anatase to rutile. The bandgap energies showed lower than pure anatase crystalline phase. The types of Ti–N–O (substitutional N) and/or Ti–O–N (interstitial N) bonding were formed into TiO2 lattice investigated by XPS technique. The photodegradation of ciprofloxacin increased with increasing of nitrogen contents. The N–TiO2 catalysts can generate OH radical and in-situ OH radical thought the direct photocatalytic degradation of coumarin and ciprofloxacin, respectively. Since, increasing of nitrogen content can increasingly produce OH radical to more react with organic pollutants. The de-mineralization by using the highest nitrogen content sample showed approximately 66% removal at 4 h of reaction time.

The effects of tacticity and molecular weight (MW) of isotactic polypropylene (iPP) on crystallization kinetic and crystal morphology were investigated by in-situ isothermal crystallization using simultaneous synchrotron small-angle X-ray scattering (SAXS), wide-angle X-ray diffraction (WAXD) and polarized optical microscopy (POM) techniques. Several quantitative parameters were extracted and analyzed in details. It was found that tacticity notably influenced the rate of nuclei seeding, where the high-tacticity iPP sample exhibited a faster nucleation rate. However, tacticity affected only slightly on the crystallization and normalized spherulite-growth rates. Inversely, the MW strongly influenced the crystal lamellar morphology, in which the amorphous layer thickness (La) was found to be larger in high-MW iPP than that in low-MW iPP. These findings indicated the behavior of “tapering” in the lamellar width during crystal growth, where tacticity and MW both played a role in this process.

The information provided by different characterisation methods when measuring particle size varies depending on the chosen technique and analytical approach (e.g. light scattering, transmission electron microscopy, spectroscopy, x-ray scattering). This in turn has an impact on the accuracy of the results as well as comparability between methods and overall confidence on the analyses. The present study used a common sol-gel reaction to synthesise amorphous silica nanoparticles (aSiNPs) and characterised the product purity and homogeneity. The reaction involved hydrolysis and condensation of tetraethyl orthosilicate (TEOS) in the presence of lysine, which acted as catalyst for the silica production and also as a capping agent for particle size control in a suspension kept at pH 8-10. According to DLS data, the stock suspension was stable for at least 6 months in Milli Q water without surfactant when kept at 4°C. This study focused on multi-method size and shape characterisation of the aSiNPs, involving the following techniques: DLS, TEM, FTIR, STEM and SAXS. These techniques provided information on hydrodynamic diameter, core particle dimensions, sphere equivalent size, and radius of gyration. Our results show two particle populations, one around 2 nm and the other around 7 nm in diameter. Notably, these two populations are not resolved (i.e. “visible”) by all methods used.