Polyacrylamide–graft–poly(ethylene oxide)

Water-soluble graft copolymers were synthesized by copolymerization of acrylamide with mono-methoxy-poly(ethylene oxide)-methacrylates (Me-PEO-MA). The Me-PEO-MA macromers were synthesized by a catalytic esterification of methacrylic acid with mono-methoxy-poly(ethylene glycol)s with different molecular weights. The graft copolymers obtained were characterized by ¹H-NMR spectroscopy, gel permeation chromatography (GPC) and Ubbelohde viscosimetry. The rheological behaviour of aqueous polymer solutions, which are expected to show hydrophobic association at elevated temperatures, was studied with a cone and plate-rheometer.     

Poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide)-g-poly(vinyl pyrrolidone): synthesis and characterization

Pluronic poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) (PEO-PPO-PEO) block copolymers are grafted with poly(vinyl pyrrolidone) by free radical polymerization of vinyl pyrrolidone with simultaneous chain transfer to the Pluronic in dioxane. This modified polymer has both thermal responsiveness and remarkable capacity to interact with a wide variety of hydrophilic and hydrophobic pharmaceutical agents which is very attractive for medical applications. The chemical structure of the graft copolymers was characterized by FTIR and 1H NMR spectroscopy. Polymerization conditions such as initiators, feed ratio, and reaction times are studied to obtain the ideal graft copolymer.     

Thermogelling polymers composed of poly(cyclohexylenedimethylene adipate) and poly(ethylene glycol)

Block copolymers composed of hydrophilic poly(ethylene glycol) (PEG) and hydrophobic biodegradable polyesters have been reported as thermogelling polymers, because they feature temperature-dependent sol-to-gel or gel-to-sol transitions in aqueous solutions. In this study, a series of thermogelling poly(ethylene glycol methyl ether)-block–poly(cyclohexylenedimethylene adipate)-block–poly(ethylene glycol methyl ether) triblock copolymers and PEG-block–poly(cyclohexylenedimethylene adipate) multiblock copolymers was synthesized by reacting hydroxyl-terminated poly(cyclohexylenedimethylene adipate) (PCA) with poly(ethylene glycol methyl ether) and PEG, respectively, using 1,6-diisocyanatohexane as the coupling agent. Two hydroxyl-terminated PCAs, i.e., poly(1,4-cyclohexylenedimethylene adipate) and poly(1,3/1,4-cyclohexylenedimethylene adipate), were synthesized by the condensation reaction of adipic acid (AA) with 1,4-cyclohexanedimethanol (CHDM) and 1,3/1,4-CHDM, respectively, and used as the hydrophobic polyester blocks of these thermogelling copolymers to compare the effect of crystallinity on the sol-to-gel transition behavior.The polymers were characterized using proton nuclear magnetic resonance, Fourier transform infrared spectroscopy, gel permeation chromatography, differential scanning calorimetry, solubility testing, and rheological analysis. Experimental results revealed that the structure of the PCA block (crystalline vs. amorphous), the molecular weights of the hydrophobic PCA and hydrophilic PEG blocks, and the type of thermogelling polymer (triblock vs. multiblock) influenced the solubility, polymer micelle packing characteristics, maximum storage modulus, and sol-to-gel temperature of the polymers. Among all the samples at 40 wt.% aqueous solutions, triblock copolymer TB3 showed sol-to-gel temperature at 22 °C, and had the highest maximum storage modulus about 170 Pa.     

Poly(ethylene imine)‐graft‐poly(ethylene oxide) brush‐like copolymers: Preparation,thermal properties,and selective supramolecular inclusion complexation with α‐cyclodextrin

Poly(ethylene imine)‐graft‐poly(ethylene oxide) (PEI‐g‐PEO) copolymers were synthesized via Michael addition reaction between acryl‐terminated poly(ethylene oxide) methyl ether (PEO) and poly(ethylene imine) (PEI). The brush‐like copolymers were characterized by means of Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. It is found that the crystallinity of the PEO side chains in the copolymers remained unaffected by the PEI backbone whereas the crystal structure of PEO side chains was altered to some extent by the PEI backbone. The crystallization behavior of PEO blocks in the copolymers suggests that the bush‐shaped copolymers are microphase‐separated in the molten state. The PEO side chains of the copolymers were selectively complexed with α‐cyclodextrin (α‐CD) to afford hydrophobic side chains (i.e., PEO/α‐CD inclusion complexes). The X‐ray diffraction (XRD) shows that the inclusion complexes (ICs) of the PEO side chains displayed a channel‐type crystalline structure. It is identified that the stoichiometry of the inclusion complexation of the PEI‐g‐PEO with α‐CD is close to that of the control PEO with α‐CD. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2296–2306, 2008     

Characterization of amphiphilic hydrocarbon modified Poly(ethylene glycol) synthesized through ring-opening reaction of 2-(1-octadecenyl)succinic anhydride

Poly(ethylene glycol) (PEG) triblock and diblock amphiphilic block copolymers were synthesized from poly(ethylene glycol) and poly(ethylene glycol) monomethyl ether, respectively. The hydroxyl groups of PEG readily react with 2-(1-octadecenyl) succinic anhydride (OSA) at 140 °C through ring-opening reaction of the succinic anhydride. Both the PEG-OSA diblock and triblock copolymers are produced without use of any solvent or catalyst. The molecular structure of the copolymers was characterized by ¹H NMR and FTIR spectroscopy, and the thermal properties by DSC. The behavior of the copolymers in selective and nonselective solvents was studied by ¹H NMR spectroscopy in deuterium oxide and d-chloroform. The aggregation of the polymers in water was studied with a particle size analyzer and a transmission electron microscope (TEM) in bright field mode. The results show that the hydrophobic C₁₈ chain with intramolecular succinic anhydride linker can be attached to the hydrophilic PEG chain, an ester bond forming between the blocks. The copolymers exhibit flexible, liquid-like hydrophobic blocks even in water, which is a nonsolvent for OSA. PEG-OSA block copolymers self-organize in water, forming micellar polymer aggregates in nanoscale.     

Poly(ethylene oxide)-poly(styrene oxide)-poly(ethylene oxide) copolymers: Micellization, drug solubilization, and gelling features

Two new poly(ethylene oxide)-poly(styrene oxide) triblock copolymers (PEO-PSO-PEO) with optimized block lengths selected on the basis of previous studies were synthesized with the aim of achieving a maximal solubilization ability and a suitable sustained release, while keeping very low material expense and excellent aqueous copolymer solubility. The self-assembling and gelling properties of these copolymers were characterized by means of light scattering, fluorescence spectroscopy, transmission electron microscopy, and rheometry. Both copolymers formed spherical micelles (12-14 nm) at very low concentrations. At larger concentration (>25 wt%), copolymer solutions showed a rich phase behavior, with the appearance of two types of rheologically active (more viscous) fluids and of physical gels depending on solution temperature and concentration. The copolymer behaved notably different despite their relatively similar block lengths. The ability of the polymeric micellar solutions to solubilize the antifungal drug griseofulvin was evaluated and compared to that reported for other structurally-related block copolymers. Drug solubilization values up to 55 mg g⁻¹ were achieved, which are greater than those obtained by previously analyzed poly(ethylene oxide)-poly(styrene oxide), poly(ethylene oxide)-poly(butylene oxide), and poly(ethylene oxide)-poly(propylene oxide) block copolymers. The results indicate that the selected SO/EO ratio and copolymer block lengths were optimal for simultaneously achieving low critical micelle concentrations (cmc) values and large drug encapsulation ability. The amount of drug released from the polymeric micelles was larger at pH 7.4 than at acidic conditions, although still sustained over 1 day.     

Thermoreversible gelation of poly(ethylene oxide) biodegradable polyester block copolymers. II

Poly(ethylene oxide)-b-poly(L-lactic acid) (PEO-PLLA) diblock copolymers were synthesized via a ring opening polymerization from poly(ethylene oxide) and l -lactide. Stannous octoate was used as a catalyst in a solution polymerization with toluene as the solvent. Their physicochemical properties were investigated by using infrared spectroscopy, ¹H-NMR spectroscopy, gel permeation chromatography, and differential scanning calorimetry, as well as the observational data of gel-sol transitions in aqueous solutions. Aqueous solutions of PEO-PLLA diblock copolymers changed from a gel phase to a sol phase with increasing temperature when their polymer concentrations are above a critical gel concentration. As the PLLA block length increased, the gel-sol transition temperature increased. For comparison, diblock copolymers of poly(ethylene oxide)-b-poly(l -lactic acid-co-glycolic acid) [PEO-P(LLA/GA)] and poly(ethylene oxide)-b-poly(dl -lactic acid-co-glycolic acid) [PEO-P(DLLA/GA)] were synthesized by the same methods, and their gel-sol transition behaviors were also investigated. The gel-sol transition properties of these diblock copolymers are influenced by the hydrophilic/hydrophobic balance of the copolymer, block length, hydrophobicity, and stereoregularity of the hydrophobic block of the copolymer. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2207–2218, 1999     

Synthesis,self‐assembly,drug‐release behavior,and cytotoxicity of triblock and pentablock copolymers composed of poly(ε‐caprolactone), poly(L‐lactide), and poly(ethylene glycol)

Biocompatible and biodegradable ABC and ABCBA triblock and pentablock copolymers composed of poly(ε‐caprolactone) (PCL), poly(L ‐lactide) (PLA), and poly(ethylene glycol) (PEO) with controlled molecular weights and low polydispersities were synthesized by a click conjugation between alkyne‐terminated PCL‐b‐PLA and azide‐terminated PEO. Their molecular structures, physicochemical and self‐assembly properties were thoroughly characterized by means of FT‐IR, ¹H‐NMR, gel permeation chromatography, differential scanning calorimetry, wide‐angle X‐ray diffraction, dynamic light scattering, and transmission electron microscopy. These copolymers formed microphase‐separated crystalline materials in solid state, where the crystallization of PCL block was greatly restricted by both PEO and PLA blocks. These copolymers self‐assembled into starlike and flowerlike micelles with a spherical morphology, and the micelles were stable over 27 days in aqueous solution at 37 °C. The doxorubicin (DOX) drug‐loaded nanoparticles showed a bigger size with a similar spherical morphology compared to blank nanoparticles, demonstrating a biphasic drug‐release profile in buffer solution and at 37 °C. Moreover, the DOX‐loaded nanoparticles fabricated from the pentablock copolymer sustained a longer drug‐release period (25 days) at pH 7.4 than those of the triblock copolymer. The blank nanoparticles showed good cell viability, whereas the DOX‐loaded nanoparticles killed fewer cells than free DOX, suggesting a controlled drug‐release effect. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010     

Application of New Modified Poly(ethylene Oxide)-Block-Poly(propylene oxide)-Block-Poly(ethylene oxide) Copolymers as Demulsifier for Petroleum Crude Oil Emulsion

Water soluble nonionic amphiphilic block copolymers based on hydrophilic poly(ethylene glycol) (PEG) and hydrophobic poly(propylene glycol) (PPG) were prepared. Poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) copolymers, PEG-PPG-PEG, were prepared in the normal condition. The chemical composition and molecular weights of the prepared copolymers were determined from ¹H NMR and GPC techniques. The surface properties of the prepared surfactants were determined by measuring the surface tension at different temperatures. The prepared nonionic surfactants were evaluated as demulsifiers for water in crude-oil emulsions that were pronounced at different ratios of crude oil: water at 318 K and 333 K. The experimental results showed that the dehydration rate of the prepared demulsifiers reached 100% based on demulsifier chemical compositions and concentrations.     

Preparation and characterization of biodegradable nanoparticles based on amphiphilic poly(3-hydroxybutyrate)-poly(ethylene glycol)-poly(3-hydroxybutyrate) triblock copolymer

Amphiphilic triblock copolymers of poly(3-hydroxybutyrate)-poly(ethylene glycol)-poly(3-hydroxybutyrate) (PHB-PEG-PHB) were directly synthesized by the ring-opening copolymerization of β-butyrolactone monomer using PEG as macroinitiator. Their structure, thermal properties and crystallization were investigated by ¹H NMR, differential scanning calorimetry (DSC) and X-ray diffraction. It was found that both PHB and PEG blocks were miscible. With the increase in the PHB block length, the triblock copolymers became amorphous because amorphous PHB block remarkably depressed the crystallization of the PEG block. Biodegradable nanoparticles with core-shell structure were prepared in aqueous solution from the amphiphilic triblock copolymers, and characterized by ¹H NMR, SEM and fluorescence. The hydrophobic PHB segments formed the central solid-like core, and stabilized by the hydrophilic PEG block. The nanoparticle size was close related to the initial concentrations of the nanoparticle dispersions and the compositions of the triblock copolymers. Moreover, the PHB-PEG-PHB nanoparticles also showed good drug loading properties, which suggested that they were very suitable as delivery vehicles for hydrophobic drugs.     

聚乙二醇-聚谷氨酸-聚丙氨酸三嵌段共聚物的合成及其胶束的pH-响应性药物控制释放

通过大分子引发剂ω-胺基-α-甲氧基聚乙二醇引发N-羧基-α-氨基环内酸酐开环聚合和酸性水解制备了一种具有pH-响应性的三嵌段共聚物聚乙二醇-聚谷氨酸-聚丙氨酸(mPEG-PLGA-PLAA).通过核磁共振、ζ-电势、动态光散射、电子显微镜等手段表征了此类三嵌段共聚物的自组装过程及所形成胶束的pH-响应性.使用圆二色谱和红外光谱,分析了胶束结构随环境pH值转变过程中聚氨基酸链段二级结构的变化.以阿霉素作为模型药物,研究了三嵌段共聚物的载药能力和在不同pH条件下的药物释放能力.在碱性条件下,PLGA链段去质子化,链段从疏水性变为亲水性,胶束中间层由于水合作用变得松散,药物释放速率增加;在酸性条件下,PLGA链段质子化,不带电荷,与阿霉素药物分子间的静电相互作用消失.同时,PLGA链段α-螺旋含量增加,形成由链内氢键维持的刚性棒状结构,将链段周围包埋的药物分子"挤出",加速了药物的释放.     

Microstructure and morphology of self‐assembling multiblock poly(ethylene‐1‐butene)‐n copolymers in solution studied by wide‐Q small‐angle neutron scattering and microscopy

Multiblock ethylene‐1‐butene copolymers (PEB‐n) with graded ethylene content (where n is the number of ethyl branches per 100 backbone carbons) represent efficient cold filter plugging point (CFPP) depressants for crude oils and middle distillates. The aggregation behavior and the interaction with wax molecules of a tetrablock PEB‐2.6/PEB‐6.0/PEB‐10.9/PEB‐13.2 and triblock PEB‐6.5/PEB‐8.9/PEB‐10.1 copolymers in decane solutions were investigated over a wide temperature range by combining different small‐angle neutron scattering techniques and optical microscopy. The experimental results revealed in the decrease of temperature formation and evolution of multisized structural levels showing a hierarchical organization on the length scale from 1 nm up to 10 μm. One‐dimensional polymer aggregates arising as initial structures associate and branch that lead to the occurrence of complex macroaggregates with diffusive interfaces and sizes of several microns. The one‐dimensional copolymer structure shows longitudinal density modulation and micellar‐like substructures in neat polymer solutions. When wax is added, this structure becomes more homogeneous in decrease of temperature as a consequence of the cocrystallization of wax and copolymer. The wax crystallization in board‐like objects of much smaller size than required by the CFPP criterion of oil and refinery industry (filter mesh size of 45 μm) is templated and controlled by the assembling features of the crystalline–amorphous PEB‐n multiblock copolymers. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011     

Synthesis and characterization of amphiphilic diblock copolymers of methyl tri(ethylene glycol) vinyl ether and isobutyl vinyl ether

Water-soluble diblock copolymers of methyl tri(ethylene glycol) vinyl ether (hydrophilic block) and isobutyl vinyl ether (hydrophobic block) of different molecular weights and composition were synthesized by living cationic polymerization. The molecular weight and comonomer composition of these copolymers were determined by GPC and ¹H NMR spectroscopy, respectively. Aqueous solutions of the copolymers were characterized in terms of their micellar behavior using dynamic light scattering, aqueous GPC, and dye solubilization. All the copolymers formed aggregates with the exception of a diblock copolymer with only two hydrophobic monomer units. The micellar hydrodynamic size scaled with the 0.61 power of the number of hydrophobic units, in good agreement with a theoretical exponent of 0.73. An increase in the length of the hydrophobic block at constant hydrophilic block length or an increase in the overall polymer size at constant block length ratio both resulted in lower critical micelle concentrations (cmcs). The cloud points of 1% w/w aqueous solutions of the polymers were determined by turbidimetry. An increase in the length of the hydrophobic block at constant hydrophilic block length caused a decrease in the cloud points of the copolymers. However, an increase in the overall polymer size at constant block length ratio led to an increase in the cloud point. © 1996 John Wiley & Sons, Inc.     

Syntheses of amphiphilic biodegradable copolymers of poly(ethyl ethylene phosphate) and poly(3-hydroxybutyrate) for drug delivery

Biodegradable and amphiphilic triblock copolymers poly(ethyl ethylene phosphate)-poly(3-hydroxy-butyrate)-poly(ethyl ethylene phosphate) (PEEP-b-PHB-b-PEEP) have been successfully synthesized through ring-opening polymerization. The structures are confirmed by gel permeation chromatography and NMR analyses. Crystallization investigated by X-ray diffraction reveals that the block copolymer with higher content of poly(ethyl ethylene phosphate) (PEEP) is more amorphous, showing decreased crystallizability. The obtained copolymers self-assemble into biodegradable nanoparticles with a core-shell micellar structure in aqueous solution, verified by the probe-based fluorescence measurements and transmission electronic microscopy (TEM) observation. The hydrophobic poly(3-hydroxybutyrate) (PHB) block serves as the core of the micelles and the micelles are stabilized by the hydrophilic PEEP block. The size and size distribution are related to the compositions of the copolymers. Paclitaxel (PTX) has been encapsulated into the micelles as a model drug and a sustained drug release from the micelles is observed. MTT assay also demonstrates that the block copolymers are biocompatible, rendering these copolymers attractive for drug delivery. Supported by the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No.20060358036)     

Synthesis and characterization of novel biodegradable copolyesters by transreaction of poly(ethylene terephthalate) with copoly(succinic anhydride/ethylene oxide)

Poly(ethylene terephthalate)/copoly(succinic anhydride/ethylene oxide) copolymers, (PET/PES copolymers) were synthesized by the transreaction between PET and PES and characterized with GPC, ¹H NMR, and DSC. Most of the copolymers obtained were random copolymers. The films cast of these copolymers were transparent. The thermal, mechanical properties, and biodegradability of the copolymers obtained were studied with respect to the composition and lengths of aliphatic and aromatic units in the copolymers. In the copolymers having high PET content, the melting points, due to the PET segment, were observed by DSC measurement, although the fusion heats of the copolymers were small. The enzymatic hydrolyzability by a lipase from Rhizopus arrhizus and biodegradability by activated sludge of the copolymers decreased with an increase in PET content. When the length of succinic acid unit in the copolymer was below 2, the hydrolyzability of the copolymers decreased considerably. The tensile strengths of the cast films prepared from the copolymers synthesized by the transreaction increased with an increase in PET content, whereas, the elongations at break decreased. Their tensile strengths were half, and the elongations were double compared to those of PET homopolymer film. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4478–4489, 2000     

Stabilized amphiphilic poly(styrene-co-diene)-b-poly(ethylene oxide) aggregates

Anionic copolymerization and Williamson reaction of PS-co-PD (d-isoprene (I) or butadiene (B)) prepolymers (bearing hydroxyl or benzyl bromide end groups) and ethylene oxide or mono-methyl poly(ethylene glycol) (PEGs) were used to prepare a series of PS-co-PD-b-PEO amphiphilic copolymers. Investigations on the association and self-assembly of copolymers in dilute organic and in mixed organic/water solutions have been carried out both by light scattering and microscopic measurements. Nanosized and microsized species have been observed. Their shape depends on the hydrophobic/hydrophilic blocks ratio as well as on the solvent composition. Attempts on stabilizing the morphology of the aggregates/micelles have been made by UV-induced cross-linking of diene entities. It has been found that in some experiments, the stabilization proceeds throughout morphological rearrangement determined by the solvent nature and by the cross-linking protocol.     

pH-induced micelle formation of poly(histidine-co-phenylalanine)-block-poly(ethylene glycol) in aqueous media

Poly[(L-histidine)-co-(L-phenylalanine)]-block-poly(ethylene glycol) (HF-b-PEG) diblock copolymers were synthesized to be used for preparation of pH-sensitive polymeric micelles. First, HF block was synthesized by ring opening copolymerization of L-histidine and L-phenylalanine N-carboxyanhydride, and then the resulting copolymer was coupled with PEG. The pKa value of diblock copolymer can be controlled by adjusting the histidine/phenylalanine ratio in HF block. It is observed that the block copolymers form micelles in aqueous media and that the micelles are spherical in shape with a unimodal distribution. The micelle is formed at pH higher than pKa of block copolymer while it is not formed at lower pH. This is because the protonation of histidine residue in the HF block converts the hydrophobic core into hydrophilic one at lower pH. Acid-Base titration profile of HF41(5600)-b-PEG, HF56(5500)-b-PEG, H(5100)-b-PEG and 0.1 N NaCl.     

聚L-丙氨酸-聚乙二醇嵌段共聚物的胶束化行为研究

以氨基聚乙二醇单甲醚(MPEG-NH₂)为大分子引发剂, 采用开环聚合方法合成了聚L-丙氨酸-聚乙二醇嵌段共聚物(PAME), 并对其结构进行了表征; 用圆二色谱(CD)研究了嵌段共聚物在水溶液中的二级结构, 用芘荧光探针技术研究了共聚物胶束的形成及其临界胶束浓度(CMC), 利用动态光散射(DLS)和透射电镜(TEM)研究了胶束的粒径分布和形态. 结果表明, 在水溶液中共聚物链以α-螺旋构象形式存在, 在一定条件下嵌段共聚物能够形成球形的稳定胶束, PAME-1形成胶束的CMC为1.99×10^-5 mol/L, CMC值受共聚物中聚L-丙氨酸(PLA)链段含量的影响.     

Micellization and controlled release properties of methoxy poly(ethylene glycol)-b-poly(D,L-lactide-co-trimethylene carbonate)

Amphiphilic block copolymers composed of D,L-lactide, trimethylene carbonate and the methoxy poly (ethylene glycol) (PETLA) were synthesized with ringopening copolymerization. Studies on the micellization and drug-controlled release behavior of PETLA were performed. Both of the copolymers and the micelles were characterized with the methods of ¹H nuclear magnetic resonance (¹H-NMR), fluorescence spectroscopy, gel permeation chromatographic (GPC), dynamic light scattering (DLS), transmission electron microscopy (TEM) and ultraviolet-visible spectroscopy (UV). As a result, the critical micelle concentration of the copolymer was decreased with the increase of the hydrophobic chain length. DLS results indicated the diameters of the micelle were increased with increasing hydrophobic length. TEM photographs illustrated that micelles MT1 were regularly spherical with the diameter from 30 nm to 40 nm. Taking 9-nitro-20(S)-camptothecin (9-NC) for the model drug, the release profiles in vitro show that the release behavior from micelles was controllable and nearly in zero order after the initial burst release. __________ Translated from Acta Polymerica Sinica, 2008, 2 (in Chinese)     

Langmuir and Langmuir-Blodgett films of poly(ethylene oxide)-b-poly(epsilon-caprolactone) star-shaped block copolymers

Self-assembly of poly(ethylene oxide)-block-poly(epsilon-caprolactone) five-arm stars (PEO-b-PCL) was studied at the air/water (A/W) interface. The block copolymers consist of a hydrophilic PEO core with hydrophobic PCL chains at the star periphery. All the polymers have the same number of ethylene oxide repeat units (9 per arm), and the number of epsilon-caprolactone repeat units ranges from 0 to 18 per arm. The Langmuir monolayers were analyzed by surface pressure/mean molecular area isotherms, compression-expansion hysteresis experiments, and isobaric relaxation measurements, and the Langmuir-Blodgett (LB) films' morphologies were investigated by atomic force microscopy (AFM). PCL homopolymers crystallize directly at the A/W interface in a narrow surface pressure range (11-15 mN/m). In the same pressure region, the star-shaped block copolymers undergo a phase transition corresponding to the collapse and the crystallization of the PCL chains as shown by the presence of a pseudoplateau in the isotherms. The LB films were prepared by transferring the Langmuir monolayers onto mica substrates at various surface pressures. AFM imaging confirmed the formation of PCL crystals in the LB monolayers of the PCL homopolymers and of the copolymers, but also showed that the PCL segments can undergo additional crystallization after monolayer transfer during water evaporation. The PCL crystal morphologies were also strongly influenced by the surface pressure and by the PEO segments.