Phase Contrast Optical Microscopy Research Articles

Effect of sonic stimulation on Bacillus endospore germination.

This study investigates the effect of sonic stimulation on Bacillus endospore germination. Germinating endospores in a microtiter plate were exposed to audible sound wave generated by an array of piezoelectric transducers. In situ germination kinetics was measured by terbium-dipicolinate fluorescence assay, optical density measurement and phase contrast microscopy. Fluorescence results revealed that sonic stimulation (5 kHz at 90 dB) promoted the germination speed by 43.7%± 11.3% and final germination level by 61.7% ± 11.9% of Bacillus atrophaeus. This acoustic energy absorbed by endospores is postulated to change membrane permeability and increase enzyme activities; thereby, expediting the germination process. This also raises the likelihood of dormant endospores undergoing germination because of a rapid release of unidentified chemical mediators for quorum sensing. On the other hand, acoustic effect was not observed in B. subtilis endospores. This may be attributed to the different spore aspect ratio, 1.43 ± 0.05 for B. atrophaeus and 2.02 ± 0.08 for B. subtilis, which results in a difference in specific absorption rates towards audible sound waves. Our results demonstrate the modulation of endospore germination by an external field to shed light on germination mechanism and cell-wave interaction.

Microscopic study of the morphology and metabolic activity of Fusarium oxysporum f. sp. gladioli treated with Jatropha curcas oil and derivatives

The fungus Fusarium oxysporum f. sp. gladioli is one of the main pathogenic microorganisms of the ornamental genus Gladiolus. The attack of this microorganism includes corms and different plant phenological stages. In this study, different microscopic techniques and fluorochromes were used to evaluate the effect of J. curcas oil and acylglycerides, namely trilinolein, triolein, monomyristin and dimyristin, on the morphology, membrane integrity (%), viability (%) and germination (%) of F. oxsporum f sp. gladioli. Phase-contrast optical photomicrographs and scanning microscopy showed that J. curcas oil and the triglycerides triolein and trilinolein caused the formation of numerous vacuoles, alterations in the morphology of the outer covering of the mycelium and conidia, and inhibition of membrane activity in the fungus during 24h of incubation. The fluorochromes used detected no permanent damage to the viability of the conidia. The high germination percentage of the conidia of Fusarium oxysporum f. sp. gladioli indicates that the damage caused by the application of the treatments was fungistatic rather than fungicidal and did not cause cell death.

Thermally driven smoothening of molecular thin films: Structural transitions in n-alkane layers studied in real-time.

We use thermal annealing to improve smoothness and to increase the lateral size of crystalline islands of n-tetratetracontane (TTC, C44H90) films. With in situ x-ray diffraction, we find an optimum temperature range leading to improved texture and crystallinity while avoiding an irreversible phase transition that reduces crystallinity again. We employ real-time optical phase contrast microscopy with sub-nm height resolution to track the diffusion of TTC across monomolecular step edges which causes the unusual smoothing of a molecular thin film during annealing. We show that the lateral island sizes increase by more than one order of magnitude from 0.5 μm to 10 μm. This desirable behavior of 2d-Ostwald ripening and smoothing is in contrast to many other organic molecular films where annealing leads to dewetting, roughening, and a pronounced 3d morphology. We rationalize the smoothing behavior with the highly anisotropic attachment energies and low surface energies for TTC. The results are technically relevant for the use of TTC as passivation layer and as gate dielectric in organic field effect transistors.

Water compartmentalization, cell viability and morphology changes monitored under stress by 1H-NMR relaxometry and phase contrast optical microscopy

The quasi-continuous distributions of spin-lattice (T1) and spin-spin (T2) relaxation times of a population of cells kept under stress conditions for about 400 h has been obtained by 1H-NMR relaxometry. The comparison with the results obtained from the analysis of cell viability and morphological variations by phase contrast optical microscopy and performed with acquisition times, duration and conditions matching those of the relaxometry experiments allowed us to identify three main phases of the processes related to the exchanges of water and remodeling of cellular compartments: between 0 and 40 h the intra- and extra-cellular compartments are characterized by a T2 of ~250 ms and of ~2 s respectively and the cell population half-life has been experimentally evaluated to be ~45 h; after 40 and until 100 h cells NMR parameter changes suggest that the confined water is increasing according to the progressive fragmentation of the cells membrane; over 100 h almost all cells are non-viable and the constancy of the main NMR parameters reflects the reaching of the final equilibrium of the system. In conclusion our observations validated the use of NMR as a non-destructive, non-invasive powerful technique for monitoring the progression of cellular processes involving compartments water exchange and reorganization.

Red-Alarm against Fibers Concentration of Asbestos in Atmospheric Urban Area of Tehran Capital of Iran

Asbestos is the natural silicate minerals with attractive physical properties such as; resistant to fire, electrical and chemical solvents. It composes of six types of materials include; Serpentine group; Chrysotile, Amphibole groups; amosite (Brown), Crocidolite (Blue) and other materials. It is popular for low cost favorable properties. All the six types have asbestiform fiber crystal, and can induce carcinogen in human. It was generally used during the boom of the industrial revolution since 1866, and the first publish of the unhealthy effect of asbestos reported nearly 30 years after industrial usage since 1899. The most common usage types of asbestos consist of chrysotile and the crocidolite. All the current types widely use in the building structures, brake pads (1) and clutch disc (2). Daily inhalation of asbestos occurs in the ambient air of cities which associated with poor air quality control. This event leads to generation of asbestosis disease (3), cancer development and mortality (4) and morbidity among at-risk population, such as asbestos –exposed workers (5), non-occupational subjects, people who living in the asbestos fibers exposed environment (6). Corresponding author: Agin Kh, MD. Associated Professor of the Respiratory Medicine. Logman Hakeem General Teaching Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran E-mail: khosrow.agin@yahoo.com & Agin@sbmu.ac.ir Long time exposure with asbestos leads to the development of chronic lung disease. It can be developed as occupational and non-occupational conditions (7, 8). Mesothelioma and lung cancer are the known causes of the asbestos exposure (9). In addition, it produces risk development of esophageal gastric, colorectal cancer (10) and head and neck squamous cell carcinoma (11). Children also are at risk of cancer by asbestos inhalation (12). The accepted threshold for asbestos is 100 fiber/liter that measured by phase-contrast optical microscopy (PCM) (13). There is a direct relationship between high level of asbestos in air and lung cancer (14). The first use of asbestos in Iran returns to World War II during the foundation of railroad and beginning product of cement manufacture in 1958 (15). Meanwhile, asbestos is producing up to 55000 tones cement in Iran annually, and near the 94% of produced cement that used in our country. The current output predominantly detected in the manufacture of building material (16), as pipe in the water delivery network (5000 Kilometer), brake pads (17) and pad shoes (15, 18). The most common types of asbestos observed in the ambient urban area of Tehran, including; Chrysotil (60%), tremolite (10%), antophylline (10%) (19). The rate of asbestos in air of Tehran- Iran was 68 times higher in the USA in 2009 (19). Our ministry of health in 2013 reported that the asbestos levels in the Tehran was 50-100 times more than the standard definition of the world (20). It seems that the deadline of depreciating has been finalized to the issue of asbestos fibers in our atmospheric cities. It requires a national decision, though the creating practice planes in reducing the level of usage and replacement that with safe materials.

Study on the concentration of airbone respirable asbestos fibres in rural areas of the Lublin region in south-east Poland.

The objective of the study was measurement of the concentrations of airborne asbestos fibres in the rural environment of the Lublin Region in south-east Poland. Measurements of concentrations of respirable asbestos fibres were carried out in the rural areas of the Lublin Region (Lublin and Włodawa counties) for a period of 24 months. The studies were conducted on 3 farms with various technical conditions of asbestos-containing materials: Farm A - good technical condition of asbestos products, Farm B - poor technical condition, and Farm C - with no asbestos containing products and no such products in its direct vicinity (up to 500 m). On the selected farms, 3 samples on each were simultaneously collected at 3 measuring sites. During the period 2009-2011, a total number of 216 samples were collected on all farms. Sampling was performed using JSH 16,000 stationary aspirators, with air flow velocity of 16 l/min. and sampling time 60-80 minutes. The number of fibres on filters was determined using an optical phase contrast microscope. The study showed that the mean concentration of respirable asbestos fibres on the farms examined was 296 fibres•m (-3). The highest concentrations were noted on Farm B was 529 fibres•m (-3), on average; on farm A the mean concentration of respirable fibres was 328 fibres•m (-3), whereas the lowest mean concentration of airborne respirable asbestos fibres was noted on farm C, where there were no asbestos products (30 fibres•m(-3)).

Supertough polylactide materials prepared through in situ reactive blending with PEG-based diacrylate monomer.

Supertough biocompatible and biodegradable polylactide materials were fabricated by applying a novel and facile method involving reactive blending of polylactide (PLA) and poly(ethylene glycol) diacylate (PEGDA) monomer with no addition of exogenous radical initiators. Torque analysis and FT-IR spectra confirm that cross-linking reaction of acylate groups occurs in the melt blending process according to the free radical polymerization mechanism. The results from differential scanning calorimetry, phase contrast optical microscopy and transmission electron microscopy indicate that the in situ polymerization of PEGDA leads to a phase separated morphology with cross-linked PEGDA (CPEGDA) as the dispersed particle phase domains and PLA matrix as the continuous phase, which leads to increasing viscosity and elasticity with increasing CPEGDA content and a rheological percolation CPEGDA content of 15 wt %. Mechanical properties of the PLA materials are improved significantly, for example, exhibiting improvements by a factor of 20 in tensile toughness and a factor of 26 in notched Izod impact strength at the optimum CPEGDA content. The improvement of toughness in PLA/CPEGDA blends is ascribed to the jointly contributions of crazing and shear yielding during deformation. The toughening strategy in fabricating supertoughened PLA materials in this work is accomplished using biocompatible PEG-based polymer as the toughening modifier with no toxic radical initiators involved in the processing, which has a potential for biomedical applications.

Phase behavior actuating morphology and rheological response of polybutadiene/polyisoprene blends under small amplitude oscillatory shear

The morphology evolution and the corresponding linear viscoelastic behavior of the phase-separating polybutadiene (PB)/low vinyl content polyisoprene (LPI) blend have been investigated by phase contrast optical microscopy (PCOM), small-angle light scattering (SALS) and rheometry. Two kinds of structure evolutions and rheological responses have been observed. It is found that the co-continuous structure generally gives a power law behavior of the dynamic storage modulus versus frequency and the coarsening of co-continuous structure leads to a decrease of the storage modulus. For the droplet-matrix structure, a platform modulus is observed at the mediate frequencies, followed by the typical terminal relaxation behavior of storage modulus at the extremely low frequencies. The decreasing platform modulus and increasing terminal modulus with the growth of droplets are observed and can be well interpreted by the simplified Palierne model. The platform modulus and terminal modulus at a given frequency are found to be scalable with the phase separation time. Besides, the characteristic relaxation time and domain size of the droplets have been obtained by rheology. And it seems that the rheologically determined droplet dimensions are consistent with the ones determined by PCOM and SALS.

Orientational phase-separated domains in a polyolefin blend under a temperature gradient field

We investigate the effect of a temperature gradient on the orientation of phase-separated structures in a polyolefin blend system. Phase contrast optical microscopy (PCOM) has been used to measure the morphology of phase separation via spinodal decomposition as a function of phase separation time and temperature gradient. The bicontinuous and interconnected tubelike structure, the characteristic morphology of the spinodal decomposition process, exhibits a preferential alignment along the direction of temperature gradient after phase separation. The orientation of the bicontinuous and interconnected tubelike structures gradually increases with phase separation time and temperature gradients. Also the orientation of phase-separated domains can respond really quickly to the change in the direction of external temperature gradient field. The results suggest that “thermal force” induced by the temperature inhomogeneity might play an important role in aligning phase-separated domains preferentially along the temperature gradient direction.

Study of neuron survival on polypyrrole-embedded single-walled carbon nanotube substrates for long-term growth conditions

Cultures of primary embryonic rat brain hippocampus neurons with supporting glia cells were carried out on different substrates containing polypyrrole (PPy) and/or single-walled carbon nanotubes (SWCNTs). Neuron adhesion, neurites and dendrites branching elongation, and development of neuron networks on substrates were followed by phase-contrast optical microscopy and quantified to state cell survival and proliferation. Suspensions of as-grown and purified SWCNTs were sprayed on a glass coverslips and PPy/SWCNTs were deposited by potentiodynamic electrochemical deposition. Cell neurotoxicity revealed by neuron death was very high for purified SWCNTs substrates in good agreement with [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) test showing lower viability on SWCNTs containing substrates compared with PPy-substrates and control samples probably due to the metal content and the carboxylic groups introduced during the purification. It is interesting to highlight that neurons grown on PPy-substrates adhere developing neurites and branching dendrites earlier even than on control cultures. On subsequent days the neurons are able to adapt to nanotube substrates developing neuron networks for 14-day cultures with similar patterns of complexity for control, PPy and PPy/SWCNT substrates. PPy/SWCNT substrates show a lower impedance value at frequencies under 1 Hz. We have come to the conclusion that glia cells and PPy added to the culture medium and substrates respectively, improve in some degree nanotube biocompatibility, cell adhesion and hence cell viability.

Induction of Skeletal Muscle Differentiation In Vitro by Therapeutic Ultrasound

Therapeutic ultrasound (TU) has been used for the last 50 y in rehabilitation, including treatment of soft tissues. Ultrasound waves can be employed in two different modes of operation, continuous and pulsed, which produce both thermal and non-thermal effects. Despite the large-scale use of TU, there are few scientific studies on its biologic effects during skeletal muscle differentiation. To better analyze the cellular effects of TU, we decided to follow cells in vitro. The main purpose of this study was to evaluate the effects of TU in primary chick myogenic cell cultures using phase contrast optical microscopy and immunofluorescence microscopy, followed by image analysis and quantification. Our results indicate that TU can stimulate the differentiation of skeletal muscle cells in vitro, as measured by the thickness of multinucleated myotubes, the ratio of mononucleated cells to multinucleated cells and expression of the muscle-specific protein desmin. This study is a first step toward a metrologic and science-based protocol for cell treatment under different ultrasound field exposures.

Strong enhancements of nucleation and spherulitic growth rates through amplified interfacial effects for immiscible linear polymer/comb-like copolymer double-layer films

Cellulose-graft-poly[poly(ethylene glycol) methyl ether acrylate] (Cell-g-PPEGA) and poly[poly(ethylene glycol) methyl ether acrylate] (PPEGA) comb-like copolymers were synthesized by electron transfer atom transfer radical polymerization (ARGET ATRP). PPEGA/PLA and Cell-g-PPEGA/PLA pairs are both immiscible as indicated by slightly decreasing glass transition temperatures of PLA in the blends measured by differential scanning calorimetry (DSC) and phase separation morphologies observed by a phase contrast optical microscope (PCOM). Cell-g-PPEGA/PLA and PPEGA/PLA double-layer films and neat PLA film were prepared to measure the nucleation and spherulitic growth rates during isothermal crystallization at various temperatures above the melting points of Cell-g-PPEGA and PPEGA layers by using a polarized optical microscope (POM). In contrast to our previous results on the miscible polymer pairs, covering the immiscible molten PPEGA layer can greatly accelerate the spherulitic growth rates for PLA and the Cell-g-PPEGA layer shows a similar but less significant effect. Nevertheless, nucleation density is much higher for the Cell-g-PPEGA/PLA film than for the PPEGA/PLA and neat PLA films. A significant finding is that although the whole double-layer film systems represent phase separated ones, the densely grafted PEGA chains in the comb-like copolymers can simultaneously take action to amplify the segmental mobility of PLA chains through local contacts at interfacial layers between phase separated domains, which significantly enhances the formation of chain folding lamellae of the PLA, resulting in obvious enhancements of the crystallization kinetics.

Anomalous phase separation behavior in dynamically asymmetric LCST polymer blends

The interplay of thermodynamic forces and self-generated stresses induced in different compositions, and at different quench depths on the phase behavior of dynamically asymmetric PS/PVME blends are studied. The thermodynamic phase diagram is obtained from dynamic temperature sweep experiments. Phase contrast optical microscopy and rheological measurements including linear viscoelastic behavior and the stress growth behavior are employed to investigate the time evolution of the different phase-separating morphologies. At an intermediate quench depth of 14 °C, in addition to thermodynamically controlled phase separation mechanisms (nucleation and growth, NG, and spinodal decomposition, SD), three different kinds of phase separation behavior are induced by transient gel formation due to self-induced stresses in the early stage of phase separation: (i) conventional viscoelastic phase separation (VPS), (ii) nucleation of aggregate-like PS-rich phase and subsequent formation of a percolated network by coalescence, and (iii) nucleation of an aggregate-like PS-rich phase while the dispersed-matrix morphology is preserved in the later stages of phase separation. While it is generally accepted that VPS occurs at deep quench depths, we observe the VPS mechanism at shallow quench depths which is attributed to dynamic heterogeneity in the phase-separated domains. A dynamic phase diagram which shows the effect of dynamic asymmetry on phase behavior is proposed.

Meniscus formation in a capillary and the role of contact line friction

We studied spontaneous formation of an internal meniscus by dipping glass capillaries of 25 μm to 350 μm radii into low volatile hexadecane and tributyl phosphate. X-ray phase contrast and high speed optical microscopy imaging were employed. We showed that the meniscus completes its formation when the liquid column is still shorter than the capillary radius. After that, the meniscus travels about ten capillary radii at a constant velocity. We demonstrated that the experimental observations can be explained by introducing a friction force linearly proportional to the meniscus velocity with a friction coefficient depending on the air/liquid/solid triplet. It was demonstrated that the friction coefficient does not depend on the capillary radius. Numerical solution of the force balance equation revealed four different uptake regimes that can be specified in a phase portrait. This phase portrait was found to be in good agreement with the experimental results and can be used as a guide for the design of thin porous absorbers.

Asbestos Exposure among Construction Workers During Demolition of Old Houses in Tehran, Iran

Air quality in demolition practices has seldom been evaluated in Iran. Accordingly, we evaluated asbestos exposure among Tehran construction workers during the demolition of old houses. To identify possible sources of asbestos exposure, including thermal insulations, chimney pipes and cement sheets, were all sampled. This study also were taken the personal air samples to evaluate any asbestos exposure during the demolition. The asbestos fibers found in the samples were analyzed by phase-contrast optical microscopy (PCM), scanning electron microscopy (SEM) equipped with an energy dispersive X-ray analysis, and polarized light microscopy (PLM) methods. Personal monitoring of asbestos fiber levels indicated a range from 0.01 to 0.15 PCM f/ml (0.02–0.42 SEM f/ml). The geometric mean concentrations were 0.07 PCM f/ml (0.20 SEM f/ml), which is considerably higher than the threshold limit value (TLV) proposed by American Conference of Governmental Industrial Hygienist (ACGIH), which is 0.1 f/ml. The analysis showed a presence in the bulk samples only chrysotile asbestos and an absence of the other type asbestos. Therefore, it might be expected that workers who worked in the demolition of old houses will suffer from negative effects of exposing to the asbestos fibers.

Natural rubber/styrene butadiene rubber blends prepared by ultrasonically aided extrusion

Ultrasonically aided extrusion of natural rubber (NR), styrene butadiene rubber (SBR), and NR/SBR blends with ratio of 70/30, 50/50, and 30/70 were carried out at various ultrasonic amplitudes up to 10 μm. A die pressure of NR and NR/SBR blends continuously decreased with increase of ultrasonic amplitude, while that of SBR showed a slight increase with increase in amplitude from 5.0 to 7.5 μm due to a dominant effect of SBR gel formation. Complex dynamic viscosity, minimum and maximum torque of curing curves of NR, SBR, and NR/SBR blends, and cross-link density and gel fraction of their vulcanizates were decreased by the ultrasonic treatment at an amplitude of 10 μm, due to the molecular chain scission. The latter also led to a decrease in the hardness, modulus at a strain of 100%, and abrasion resistance of NR and NR/SBR blends. However, the modulus and abrasion resistance of SBR showed an improvement at amplitude of 7.5 μm, dueto a dominant effect of gel formation. Both the tensile strength and elongation at break of ultrasonically treated NR/SBR blends showed a maximum at amplitude of 5.0 μm, with the modulus at a strain of 100% not being affected. Morphological studies using the phase-contrast optical microscope and atomic force microscopy showed a reduction in the size of rubber phases and a better homogeneity of NR/SBR blend by the ultrasonic treatment at amplitude of 5.0 μm. Accordingly, the increase in both the tensile strength and elongation at break of ultrasonically treated NR/SBR blends at an amplitude of 5.0 μm is mainly ascribed to the lower size of rubber phases and improved uniformity of blend caused by the ultrasonic treatment.

Ambient monitoring of airborne asbestos in non-occupational environments in Tehran, Iran

Airborne asbestos fiber concentrations were monitored in the urban areas of Tehran, Iran during the period of 23 August to 21 September 2012. The airborne fiber concentrations of 110 air samples collected from 15 different sites in five regions of Tehran. The monitoring sites were located 2.5 m above ground nearby the main street and heavy traffic jam. The ambient air samples were analyzed using scanning electron microscopy (SEM), with energy-dispersive X-ray analysis and phase-contrast optical microscopy (PCM). The geometric means of the airborne asbestos fiber concentrations in the outdoor living areas was 1.6 × 10−2 SEM f ml−1 (1.18 × 10−3 PCM f ml−1). This criteria is considerably higher than those reported for the levels of asbestos in outdoor living areas in the Europe and the non-occupational environment of the Korea. No clear correlation was found between asbestos fiber concentration and the relative humidity and temperature. The SEM and PLM analysis revealed that all samples examined contained only chrysotile asbestos. It can be concluded that several factor such as heavy traffic, cement sheet and pipe consumption of asbestos, and geographical conditions play an important role for the high airborne asbestos levels in the non-occupational environments.

Effect of temperature gradient on liquid-liquid phase separation in a polyolefin blend

We have investigated experimentally the structure formation processes during phase separation via spinodal decomposition above and below the spinodal line in a binary polymer blend system exposed to in-plane stationary thermal gradients using phase contrast optical microscopy and temperature gradient hot stage. Below the spinodal line there is a coupling of concentration fluctuations and thermal gradient imposed by the temperature gradient hot stage. Also under the thermal gradient annealing phase-separated domains grow faster compared with the system under homogeneous temperature annealing on a zero-gradient or a conventional hot stage. We suggest that the in-plane thermal gradient accelerates phase separation through the enhancement in concentration fluctuations in the early and intermediate stages of spinodal decomposition. In a thermal gradient field, the strength of concentration fluctuation close to the critical point (above the spinodal line) is strong enough to induce phase separation even in one-phase regime of the phase diagram. In the presence of a temperature gradient the equilibrium phase diagrams are no longer valid, and the systems with an upper critical solution temperature can be quenched into phase separation by applying the stationary temperature gradient. The in-plane temperature gradient drives enhanced concentration fluctuations in a binary polymer blend system above and below the spinodal line.

Synthesis and properties of biodegradable multiblock poly(ester‐carbonate) comprising of poly(L‐lactic acid) and poly(butylene carbonate) with hexamethylene diisocyanate as chain‐extender

A series of novel biodegradable poly(ester‐carbonate) consisting of poly(L‐lactic acid) (PLLA) and poly(butylene carbonate) (PBC) (PLLA‐b‐PBC) have been successfully synthesized by chain‐extension reaction of dihydroxyl‐terminated poly(L‐lactic acid) prepolymer (PLLA‐OH) and dihydroxyl‐terminated poly(butylene carbonate) prepolymer (PBC‐OH) using hexamethylene diisocyanate as a chain‐extender. The chemical structures and molecular weights of copolymers are characterized by 1H NMR and gel permeation chromatography. The thermal properties, morphology, and mechanical properties of PLLA‐b‐PBC are investigated by differential scanning calorimetry, thermogravimetric analysis, phase contrast optical microscopy, and mechanical testing. The results indicate that PBC soft segment slightly increases the thermal stabilities and effectively enhances the impact strength of the copolymers. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014, 131, 39158.

Effect of lower critical solution temperature phase separation on crystallization kinetics and morphology of poly(butylenes succinate)/poly(ethylene oxide) blend

The crystalline/crystalline polymer blend of poly(butylenes succinate)/poly(ethylene oxide) (PBS/PEO) exhibited lower critical solution temperature (LCST) phase separation behavior at temperatures above the melting point of PBS, which was measured by phase contrast optical microscopy (PCOM) technique. In this work, we determined the LCST phase diagram of PBS/PEO blends, and then investigated the effect of liquid–liquid phase separation (LLPS) on the crystallization kinetics and morphologies of PBS/PEO (40/60 wt/wt) blend. Based on polarized optical microscopy (POM), scanning electron microscopy (SEM) and differential scanning calorimeter (DSC) results, we found that the spherulite morphology and crystallization kinetics of PBS were strongly influenced by the initial LLPS structure; because the kinetics of liquid–liquid phase dissolution was much slower than that of crystallization. The effect of LLPS on the primary nucleation density and crystal growth rate of PBS were strongly dependent on the crystallization temperature of PBS. After a second quench to a temperature below the melting point of PEO, the fractionated crystallization of PEO was observed. The competition between the kinetics of LLPS and the driving force of PBS crystallization controlled the spatial distribution of PEO in PBS spherulites, thus essentially determined the confined conditions of the PEO crystallization. The results indicated that the LLPS was an effective process to control the crystallization kinetics and morphology in crystalline/crystalline polymer blend systems.