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Biodegradable polymers with shape memory effects (SMEs) offer promising solutions for short-term medical interventions, facilitating minimally invasive procedures and subsequent degradation without requiring secondary surgeries. However, achieving a good balance among desirable SMEs, mechanical performance, degradation rate, and bioactivities remains a significant challenge. To address this issue, we established a strategy to develop a versatile biodegradable polyurethane (PPDO-PLC) with tunable hierarchical structures via precise chain segment control. Initial copolymerization of l-lactide and ε-caprolactone sets a tunable Tg close to body temperature, followed by block copolymerization with poly(p-dioxanone) to form a hard domain. This yields a uniform microphase-separation morphology, ensuring robust SME and facilitating the development of roughly porous surface structures in alkaline environments. Cell experiments indicate that these rough surfaces significantly enhance cellular activities, such as adhesion, proliferation, and osteogenic differentiation. Our approach provides a methodology for balancing biodegradability, SMEs, three-dimensional (3D) printability, and bioactivity in materials through hierarchical structure regulation.
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Poliuretanos , Poliuretanos/química , Poliuretanos/farmacología , Proliferación Celular/efectos de los fármacos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Animales , Porosidad , Adhesión Celular/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Ratones , Poliésteres/química , Diferenciación Celular/efectos de los fármacos , Lactonas/química , Lactonas/farmacología , Humanos , Caproatos/química , Dioxanos/química , PolímerosRESUMEN
Renin-angiotensin system and adenosine monophosphate-activated protein kinase signaling pathway both play important roles in carcinogenesis, but the interplay of renin-angiotensin system and adenosine monophosphate-activated protein kinase in carcinogenesis is not clear. In this study, we researched the interaction of renin-angiotensin system and adenosine monophosphate-activated protein kinase in renal carcinogenesis of uninephrectomized rats. A total of 96 rats were stratified into four groups: sham, uninephrectomized, and uninephrectomized treated with angiotensin-converting enzyme inhibitor or angiotensin receptor blocker. Renal adenosine monophosphate-activated protein kinase and its downstream molecule acetyl coenzyme A carboxylase were detected by immunohistochemistry and western blot at 10 months after uninephrectomy. Meanwhile, we examined renal carcinogenesis by histological transformation and expressions of Ki67 and mutant p53. During the study, fasting lipid profiles were detected dynamically at 3, 6, 8, and 10 months. The results indicated that adenosine monophosphate-activated protein kinase expression in uninephrectomized rats showed 36.8% reduction by immunohistochemistry and 89.73% reduction by western blot. Inversely, acetyl coenzyme A carboxylase expression increased 83.3% and 19.07% in parallel to hyperlipidemia at 6, 8, and 10 months. The histopathology of carcinogenesis in remnant kidneys was manifested by atypical proliferation and carcinoma in situ, as well as increased expressions of Ki67 and mutant p53. Intervention with angiotensin-converting enzyme inhibitor or angiotensin receptor blocker significantly prevented the inhibition of adenosine monophosphate-activated protein kinase signaling pathway and renal carcinogenesis in uninephrectomized rats. In conclusion, the novel findings suggest that uninephrectomy-induced disturbance in adenosine monophosphate-activated protein kinase signaling pathway resulted in hyperlipidemia and carcinogenesis in tubular epithelial cells, which may be largely attenuated by renin-angiotensin system blockade, implying the interaction of renin-angiotensin system and adenosine monophosphate-activated protein kinase signaling pathway in renal carcinogenesis of uninephrectomized rats.
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Proteínas Quinasas Activadas por AMP/genética , Carcinogénesis/genética , Neoplasias Renales/genética , Sistema Renina-Angiotensina/genética , Proteínas Quinasas Activadas por AMP/metabolismo , Inhibidores de la Enzima Convertidora de Angiotensina/administración & dosificación , Animales , Modelos Animales de Enfermedad , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Antígeno Ki-67/genética , Neoplasias Renales/patología , Neoplasias Renales/cirugía , Nefrectomía , Ratas , Transducción de Señal/genética , Proteína p53 Supresora de Tumor/genéticaRESUMEN
Multistimuli-responsive shape-memory polymers are highly desirable in various applications, and numerous modes have been developed in recent years. However, most of them need to reprogram before they are ready to respond to another stimulus while one is triggered. Here, a new strategy is developed to achieve dual-stimuli-responsive triple-shape memory with non-overlapping effect in one programming cycle. Here, a series of poly(l-lactide)-poly(tetramethylene oxide) glycol copolymers (PLA-PTMEG-A) is prepared by selected dangling photoresponsive anthracene moieties on the crystalline PTMEG backbone. The architectures of the copolymers are well-controlled in order to keep a good balance between the crystallinity of the soft segment and the mobility of the anthracene moieties. Thus, PLA-PTMEG-A's can respond to heat and light with non-overlapping effect. The thermally-induced shape-memory effect (TSME) is realized by the crystallization-melting transition of PTMEG soft segments, while the light-induced shape-memory effect (LSME) is achieved by the reversible photodimerization of anthracene groups. In view of the non-overlapping effect of TSME and LSME in the copolymers, a triple-shape-memory effect triggered by dual-stimuli is realized in one programming and recovery cycle.
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Glicoles/química , Poliésteres/química , Glicoles/síntesis química , Estructura Molecular , Poliésteres/síntesis química , TemperaturaRESUMEN
Amid the rapid development of modern society, the widespread use of plastic products has led to significant environmental issues, including the accumulation of non-degradable waste and extensive consumption of non-renewable resources. Developing healable, recyclable, bio-based materials from abundant renewable resources using diverse dynamic interactions attracts increasing global attention. However, achieving a good balance between the self-healing capacity and mechanical performance, such as strength and toughness, remains challenging. In our study, we address this challenge by developing a new type of dynamic network from epoxidized soybean oil (ESO) and poly(butylene adipate-co-terephthalate) (PBAT) with good strength and toughness. For the synthetic strategy, a thiol-epoxy click reaction was conducted to functionalize ESO with thiol and hydroxyl groups. Subsequently, a curing reaction with isocyanates generated dynamic thiourethane and urethane bonds with different bonding energies in the dynamic networks to reach a trade-off between dynamic features and mechanical properties; amongst these, the thiourethane bonds with a lower bonding energy provide good dynamic features, while the urethane bonds with a higher bonding energy ensure good mechanical properties. The incorporation of flexible PBAT segments to form the rational multi-phase structure with crystalline domains further enhanced the products. A typical sample, OTSO100-PBAT100, exhibited a tensile strength of 33.2 MPa and an elongation at break of 1238%, demonstrating good healing capacity and desirable mechanical performance. This study provides a promising solution to contemporary environmental and energy challenges by developing materials that combine mechanical and repair properties. It addresses the specific gap of achieving a trade-off between tensile strength and elongation at break in bio-based self-healing materials, promising a wide range of applications.
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Energy and environmental issues have increasingly garnered significant attention for sustainable development. Flexible and shape-stable phase change materials display great potential in regulation of environmental temperature for energy saving and human comfort. Here, inspired by the water absorption behavior of salt-tolerant animals and plants in salinity environment and the Hofmeister theory, highly stable phase change salogels (PCSGs) are fabricated through in situ polymerization of hydrophilic monomers in molten salt hydrates, which can serve multiple functions including thermal management patches, smart windows, and ice blocking coatings. The gelation principles of the polymer in high ion concentration solution are explored through the density functional theory simulation and verified the feasibility of four types of salt hydrates. The high concentration chaotropic ions strongly interacted with polymer chains and promoted the gelation at low polymer concentrations which derive highly-stable and ultra-moisturizing PCSGs with high latent heat (> 200 J g-1). The synergistic adhesion and transparency switching abilities accompanied with phase transition enable their smart thermal management. The study resolves the melting leakage and thermal cycling stability of salt hydrates, and open an avenue to fabricate flexible PCM of low cost, high latent heat, and long-term durability for energy-saving, ice-blocking, and thermal management.
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Numerous biological systems in nature provide much inspiration for humanity to master diverse coloration strategies for creating stimuli-responsive materials and display devices, such as to access gorgeous structural colors from well-defined photonic structures. Cholesteric liquid crystals (CLCs) are a fascinating genre of photonic materials displaying iridescent colors responsive to circumstance changes; however, it is still a big challenge to design materials with broadband color variation as well as good flexibility and freestanding capacity. Herein, we report a feasible and flexible strategy to fabricate cholesteric liquid-crystal networks (CLCNs) with precise colors across the entire visible spectrum through molecular structure tailoring and topology engineering and demonstrate their application as smart displays and rewritable photonic paper. Influences of chiral and achiral LC monomers on the thermochromic behaviors of CLC precursors as well as on the topology of the polymerized CLCNs are systematically investigated, demonstrating that the monoacrylate achiral LC facilitated the formation of a smectic phase-chiral phase (Sm-Ch) pretransitional phase in the CLC mixture and improved the flexibility of the photopolymerized CLCNs. High-resolution multicolor patterns in one CLCN film are generated through photomask polymerization. In addition, the freestanding CLCN films show perceivable mechanochromic behaviors and repeated erasing-rewriting performances. This work opens avenues toward the realization of pixelated colorful patterns and rewritable CLCN films promising in technology fields ranging from information storage and smart camouflage to anti-counterfeiting and smart display.
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The complexity of surgical treatments for large-area soft tissue injuries makes placing large implants into injury sites challenging. Aliphatic polyesters are often used for scaffold preparation in tissue engineering owing to their excellent biodegradability and biocompatibility. Scaffolds with shape-memory effect (SME) can also avoid large-volume trauma during the implantation. However, the complexity and diversity of diseases require more adaptable and precise processing methods. Four-dimensional (4D) printing, a booming smart material additive manufacturing technology, provides a new opportunity for developing shape memory scaffolds. With the aim of personalized or patient-adaptable soft tissues such as blood vessels, we developed a feasible strategy for fabricating scaffolds with fine architectures using 4D printing crosslinkable shape memory linear copolyesters using fused deposition modeling (FDM). To overcome the weak bonding strength of each printed layer during FDM, a catalyst-free photo-crosslinkable functional group derived from biocompatible cinnamic acid was embedded into the linear copolyesters as in situ crosslinking points during FDM printing. Under ultraviolet-assisted irradiation, the resulting 4D scaffold models demonstrated excellent SME, desirable mechanical performance, and good stability in a water environment owing to the chemical bonding between each layer. Moreover, the excellent biocompatibility of the scaffold was evaluated in vitro and in vivo. The developed composite scaffolds could be used for minimally invasive soft tissue repair.
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Materiales Inteligentes , Traumatismos de los Tejidos Blandos , Humanos , Poliésteres , Ingeniería de Tejidos , Impresión TridimensionalRESUMEN
Bone tissue engineering involving scaffolds is recognized as the ideal approach for bone defect repair. However, scaffold materials exhibit several limitations, such as low bioactivity, less osseointegration, and poor processability, for developing bone tissue engineering. Herein, a bioactive and shape memory bone scaffold was fabricated using the biodegradable polyester copolymer's four-dimensional fused deposition modeling. The poly(ε-caprolactone) segment with a transition temperature near body temperature was selected as the molecular switch to realize the shape memory effect. Another copolymer segment, i.e., poly(propylene fumarate), was introduced for post-cross-linking and improving the regulation effect of the resulting bioadaptable scaffold on osteogenesis. To mimic the porous structures and mechanical properties of the native spongy bone, the pore size of the printed scaffold was set as â¼300 µm, and a comparable compression modulus was achieved after photo-cross-linking. Compared with the pristine poly(ε-caprolactone), the scaffold made from fumarate-functionalized copolymer considerably enhanced the adhesion and osteogenic differentiation of MC3T3-E1 cells in vitro. In vivo experiments indicated that the bioactive shape memory scaffold could quickly adapt to the defect geometry during implantation via shape change, and bone regeneration at the defect site was remarkably promoted, providing a promising strategy to treat bone defects in the clinic, substantial bone defects with irregular geometry.
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Osteogénesis , Procedimientos de Cirugía Plástica , Poliésteres , Huesos , Regeneración Ósea , PolímerosRESUMEN
PPDO was successfully electrospun into continuous, ultrafine fibers by using DMSO as solvent for the first time. The concentration of PPDO in DMSO and the electrospinning temperature were optimized. PPDO/LAP nanocomposites were also electrospun in DMSO. At 70 degrees C, ultrafine PPDO fibers were obtained from 35 wt% solution and the PPDO/LAP nanocomposite fibers were yielded from 55 wt% solution. Electrospun fibers of the PPDO/LAP nanocomposites showed higher degree of crystallinity due to the presence of embedded nanoparticles.
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A novel environmentally friendly thermoplastic soy protein/polyester blend was successfully prepared by blending soy protein isolate (SPI) with poly(butylene succinate) (PBS). To improve the compatibility between SPI and PBS, the polyester was pretreated by introducing different amounts of urethane and isocyanate groups before blending. The blends containing pretreated PBS showed much finer phase structures because of good dispersion of polyester in protein. Consequently, the tensile strength and modulus of blends increased obviously. A lower glass transition temperature of protein in the blends than that of the pure SPI, which was caused by the improvement of the compatibility between two phases, was observed by dynamic mechanical analyzer (DMA). The hydrophobicity, water resistance, and moisture absorption at different humidities of the blends were modified significantly due to the incorporation of PBS.
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Butileno Glicoles/química , Polímeros/síntesis química , Proteínas de Soja/química , Interacciones Hidrofóbicas e Hidrofílicas , Transición de Fase , Polímeros/química , Conformación Proteica , Resistencia a la TracciónRESUMEN
A novel poly(epsilon-caprolactone) (PCL) supramolecular network exhibiting shape-memory behavior was successfully constructed with pendant UPy units that are highly able to dimerize. The dynamic network was obtained by a simple and versatile strategy consisting of chain-extension reaction between α,ω-dihydroxyoligoPCL and hydroxylated UPy units in the presence of hexamethylene diisocyanate as a coupling agent and further intermolecular dimerization of the UPy along the polyurethane backbone. 1H NMR analyses confirmed the dynamic features of the system, and DMTA in tensile mode was investigated to assess the SMP properties. Recyclability was also assessed by taking advantage of these supramolecular networks. Further addition of cellulose nanocrystals into the polymer network enabled adjustment of the extent of the net-points and therefore the SMP features. As confirmed by dispersion tests in solution and SEM observations, these bio-based nanofillers were homogeneously distributed in the network via supramolecular interaction between the hydroxyl groups present on their surface and UPy moieties along the polyurethane backbone. Thus, the here developed nanomaterials might reveal applicability in areas where a combination of SMP and biocompatibility is needed.
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Recently, charge transfer (CT) interactions have received attention for the fabrication of supramolecular architectures due to their inherent compatibilities, directional nature and solvent tolerance. In this study, we report a shape-memory dynamic network constructed by the CT interaction between π-electron-rich naphthalene embedded in poly(ethylene glycol) (PEG-Np) and π-electron-poor six-arm methyl-viologen-ended poly(ethylene glycol) (6PEG-MV), which was verified by ultraviolet-visible spectroscopy (UV-vis), fluorescence spectra and swelling tests. Interestingly, the mechanical properties of this CT complex were dramatically enhanced compared with the control without CT interaction. Moreover, the excellent shape-memory effect (SME) was realized due to the good crystallization of the PEG segment and stable netpoints based on the CT interaction. In addition, as we expected, this supramolecular polymer network is self-healable and reprocessable.
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Amphiphilic biodegradable graft copolymer, poly(vinyl alcohol)-graft-poly(p-dioxanone) (PVA-g-PPDO), was used to prepare a new biodegradable material by blending with poly(p-dioxanone) (PPDO). The in vitro degradation properties of the copolymer and blends with different contents of PVA-g-PPDO were studied in phosphate buffer at 37 degrees C. The degradation processes of the PVA-g-PPDO and its blends with the PPDO were monitored by weight loss, viscosimetry, water uptake, differential scanning calorimetry (DSC), and scanning electron microscopy. The results of inherent viscosity and weight loss reveal that the PVA-g-PPDO has a different in vitro degradation behavior from that of PPDO, and the introducing of copolymer into the blending system may enhance the degradability of PPDO when the contents of copolymer is higher than 5%. The change of the degree of crystallization (Dc) of copolymer and blends derived from the DSC also shows that the copolymer and blends have faster degradation rates than the neat PPDO during the testing period. A degradation mechanism of the blends was postulated based on the results of the weight retention, inherent viscosity measurement, and DSC.
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Materiales Biocompatibles/química , Dioxanos , Polímeros , Alcohol Polivinílico , Materiales Biocompatibles/metabolismo , Biodegradación Ambiental , Tampones (Química) , Rastreo Diferencial de Calorimetría , Cristalización , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Peso Molecular , Viscosidad , AguaRESUMEN
Herein, we report a novel thermal/photoresponsive shape-memory polyurethane network with a pendant azobenzene group by utilizing its anisotropic-isotropic phase transitions and photoresponsive feature concurrently. To achieve this goal, the side-chain liquid crystalline polyurethane networks based on the pendant azobenzene group [SCLCPU(AZO)-Ns] were developed in a well-defined architecture. The smectic C nature of an LC phase in the polyurethane networks was confirmed by differential scanning calorimetry, polarized optical microscopy, and one-dimensional and two-dimensional wide-angle X-ray diffraction. The well-defined architecture-made SCLCPU(AZO)-N displays two distinct transition temperatures (Ttrans) (Tg and Tcl), with a difference of about 40 °C. Consequently, the excellent triple-shape-memory effect in this network was demonstrated by cyclic thermomechanical analysis. By making full use of the trans-cis photoisomerization of azobenzene, the reversible bending and unbending behaviors were realized under the light irradiation with wavelengths of 450 and 550 nm, respectively.
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Membranous glomerulonephritis (MGN) represents an immunologically mediated disease characterized by deposition of immune complexes in the glomerular subepithelial space. Persistent proteinuria at diagnosis predicts poor prognosis. Pregnancy with MGN is a risk of fetal loss and may worsen maternal renal function.Here, we report a lady with MGN and proteinuria achieved spontaneous remission and successful fetal outcome naive to any medications. The 26-year old woman had 1-year history of persistent proteinuria (5.5-12.56âg/24âhours) and biopsy-proven MGN. Histopathological characteristics included glomerular basement membrane spikes, subepithelial monoclonal IgG immunofluorescence, and diffuse electron dense deposits. She was sticking to a regular morning exercise routine without any medications. After successful delivery of a full-term baby girl, the mother had improved proteinuria (0.56âg/24âhours) and albuminuria (351.96âg/24âhours contrasting 2281.6âg/24âhours before pregnancy). The baby had normal height and body weight at 4 months old.We identified more pregnancies with MGN in 5 case reports and 5 clinical series review articles (7-33 cases included). Spontaneous remission of maternal MGN with good fetal outcome rarely occurred in mothers on immunosuppressive therapy.Mothers naive to immunosuppressive therapy may achieve spontaneous remission of maternal membranous glomerulonephritis and successful fetal outcome. Theoretically, fetus might donate stem cells to heal mother's kidney.
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Glomerulonefritis Membranosa , Complicaciones del Embarazo , Resultado del Embarazo , Adulto , Femenino , Humanos , Embarazo , Remisión EspontáneaRESUMEN
A novel light-induced shape-memory material based on poly(l-lactide)-poly(ethylene glycol) copolymer is developed successfully by dangling the photoresponsive anthracene group on the PEG soft segment selectively. For synthesis strategy, the preprepared photoresponsive monomer N,N-bis(2-hydroxyethyl)-9-anthracene-methanamine (BHEAA) is first embedded into PEG chains; then, we couple this anthracene-functionalized PEG precursor with PLA precursor to result in PLA-PEG-A copolymer. The composition of target product can be well-defined by simply adjusting the feed ratio. The chemical structures of intermediate and final products are confirmed by (1)H NMR. Differential scanning calorimetry analysis of material reveals that the PEG soft segment became noncrystallizable when 4% or more BHEAA is introduced, and this feature is beneficial to the mobility of anthracene groups in polymer matrix. The static tensile tests show that the samples exhibit rubberlike mechanical properties except for the PLA-dominant one. The reversibility of [4 + 4] cycloaddition reaction between pendant anthracene groups in PLA-PEG-A film is demonstrated by UV-vis. Eventually, the light-induced shape-memory effect (LSME) is successfully realized in PLA-PEG-A. The results of cyclic photomechanical tests also reveal that the content of PLA hard segment as well as photosensitive anthracene moieties plays a crucial role in LSME.
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INTRODUCTION: The renal renin-angiotensin system (RAS) and the ultrasensitive energy sensor AMP-activated protein kinase (AMPK) have been implicated in normal and aberrant states of the kidney, but interaction between the RAS and AMPK remains unknown. METHODS: Ninety-six rats were stratified into four groups: sham, uninephrectomised, uninephrectomised rats treated with the angiotensin-converting enzyme inhibitor lisinopril or the angiotensin receptor blocker losartan. Histopathological examination at 9 months post-operation and biochemical measurements at 3, 6 and 9 months were performed for changes in renal structure and function. The expression of AMPK and angiotensin II at 9 months was detected by immunofluorescence microscopy and western blot. RESULTS: Compared with sham rats, uninephrectomised rats demonstrated progressive glomerulosclerosis, tubular atrophy with cast formation and chronic inflammatory infiltration, in parallel to elevated serum urea, creatinine, urine total protein to creatinine ratio and reduced serum albumin. Overexpression of angiotensin II coexisted with a 85.6% reduction of phosphorylated to total AMPK ratio in the remnant kidney of uninephrectomised rats. RAS blockade by the angiotensin-converting enzyme inhibitor or angiotensin receptor blocker substantially normalised AMPK expression, morphological and functional changes of the remnant kidney. CONCLUSIONS: Uninephrectomy-induced RAS activation and AMPK inhibition in the remnant kidney could be substantially corrected by RAS blockade, suggesting a cross-talk between AMPK and RAS components in uninephrectomised rats.
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Proteínas Quinasas Activadas por AMP/metabolismo , Nefrectomía , Sistema Renina-Angiotensina , Angiotensina I/metabolismo , Angiotensina II/metabolismo , Animales , Activación Enzimática , Técnica del Anticuerpo Fluorescente , Riñón/enzimología , Riñón/patología , Riñón/fisiopatología , Masculino , Microscopía Confocal , Fosforilación , Ratas Sprague-DawleyRESUMEN
Treatment of acquired immunodeficiency syndrome (AIDS) currently relies on the use of antiretroviral drugs. Little is known about Chinese herbal medicine (CHM) outcomes in patients living with AIDS. We conducted a cohort study to investigate long-term survival among CHM-treated AIDS patients. Patients were poor farmers who contracted HIV-1 infection when selling blood in the 1990s. Symptoms of AIDS included recurring respiratory tract infections with a clinical diagnosis of pneumonia, swollen lymph nodes and weight loss. 385 patients with AIDS were included and 165 of them used a 16-herb formula for 14 days to 9 months. The eight-year survival rate was 87% for the CHM users and 34% for the non-users (increased survival probability for CHM user, 9.6; 95% CI = 6.0-15.4; p < 0.0001). Survival probability further increased 14.6-fold (95% CI = 8.2-26.1), when excluding the users who received CHM for less than three months. Zero deaths were found in patients who used CHM for six to nine months. All the survivors regained their body weight and none of them experienced a relapse of AIDS or any severe adverse events. After the CHM treatment for an average of 3.6 months, the plasma HIV load was 74.7% lower (paired t-test, p = 0.151) and the number of blood CD4+ lymphocytes increased from 253 to 314 (paired t-test, p = 0.021). Without life-long medication, CHM may be beneficial for long-term survival of AIDS patients.
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Síndrome de Inmunodeficiencia Adquirida/tratamiento farmacológico , Medicamentos Herbarios Chinos/uso terapéutico , Fitoterapia , Síndrome de Inmunodeficiencia Adquirida/inmunología , Síndrome de Inmunodeficiencia Adquirida/virología , Adolescente , Adulto , Fármacos Anti-VIH/administración & dosificación , Linfocitos T CD4-Positivos , Preescolar , Estudios de Cohortes , Quimioterapia Combinada , Medicamentos Herbarios Chinos/administración & dosificación , Femenino , Humanos , Recuento de Linfocitos , Masculino , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento , Carga Viral , Adulto JovenRESUMEN
Fractional crystallization, homogeneous nucleation of poly(ethylene glycol) (PEG) segment, and self-nucleation behavior of PEG segment within miscible double crystalline poly(butylene succinate)-poly(ethylene glycol) (PBSEG) multiblock copolymers with different composition and segment chain length were studied by differential scanning calorimetry (DSC). Surface morphology of PBSEG10K with different PEG content was investigated by atomic force microscope (AFM). Different from di- or triblock copolymers, the microstructure and confinement of PEG dispersed phase in PBS matrix phase highly depends on chain length and sequence as well as segment content. The transition point of the PEG segment content from heterogeneous to homogeneous nucleation mechanism decreased from 50 to 39 wt % with PEG segment chain length increasing from 1000 to 2000 g/mol. When PEG segment chain length increased further to 6000 and 10000 g/mol, homogeneous nucleation phenomenon took place at much lower PEG content and fractional crystallization was observed at 29 and 24 wt %, respectively. Homogeneous nucleation mechanism of PBSEG(1K-36), PBSEG(2K-26), PBSEG(6K-19), and PBSEG(10K-12) was evidenced by the large supercoolings needed for crystallization, as well as first-order crystallization kinetics obtained. Self-nucleation behaviors of PEG segment still rely on the composition of PBSEGs. In the case of heterogeneous nucleation crystallization, self-nucleation behaviors of PEG segment showed standard self-nucleation behavior with classical three self-nucleation domains. When the crystallizable chains were confined into isolated microdomains, however, self-nucleation domain (domain II) disappeared. The absence of III(A) was observed in PBSEG(2K-39), while PBSEG(6K-29) had both III(A) and III(SA). Furthermore, AFM morphology studies still indicated the confined degree of PEG segment by previous PBS crystals was profoundly influenced by segment fraction. The confinement of the PEG segment by previous PBS edge-on lamellae was observed in the sample which displays a homogeneous nucleation crystallization behavior.