Control of self‐organized low‐dimensional morphology in poly(styrene‐b‐4vinylpyridine)/polystyrene blend thin films

The surface morphologies of poly(styrene‐b‐4vinylpyridine) (PS‐b‐P4VP) diblock copolymer and homopolystyrene (hPS) binary blend thin films were investigated by atomic force microscopy as a function of total volume fraction of PS (?_PS) in the mixture. It was found that when hPS was added into symmetric PS‐b‐P4VP diblock copolymers, the surface morphology of this diblock copolymer was changed to a certain degree. With ?_PS increasing at first, hPS was solubilized into the corresponding domains of block copolymer and formed cylinders. Moreover, the more solubilized the hPS, the more cylinders exist. However, when the limit was reached, excessive hPS tended to separate from the domains independently instead of solubilizing into the corresponding domains any longer, that is, a macrophase separation occurred. A model describing transitions of these morphologies with an increase in ?_PS is proposed. The effect of composition on the phase morphology of blend films when graphite is used as a substrate is also investigated. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3496–3504, 2004     

Order‐order transitions of a triblock copolymer with a homopolymer (ABC/A) blend film induced by saturated solvent vapor annealing

The morphology transition of binary mixtures of polystyrene‐block‐poly(butadiene)‐block‐poly(2‐vinylpyridine)(SBV) triblock and polystyrene (PS) homopolymer thin films was investigated as a function of the volume fraction of added homopolymer and the annealing time in benzene vapor. It was found that the weight ratio of PS in the blends influenced the transition process. When PS content was >5%, the order‐order transition (OOT) of core‐shell cylinders (C) →sphere in “diblock Gyroid” (sdG) → sphere in lamella (sL) → sphere (S) was observed, which was similar to ABC triblock copolymer except for the increased surface area of the PS phase. When PS content reached to 10–30%, the OOT in the sequence of C → sL → S was observed. The disappearance of the Gyroid phase is due to the change of the effective volume fraction. Further increasing the PS content, C phase also disappeared and sL → S was expected to take place. © 2014 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2014 , 52, 1030–1036     

Polymerization of n‐hexyl isocyanate with CpTiCl2(OR) (R = functional group or macromolecular chain): A route to ω‐functionalized and block copolymers and terpolymers of n‐hexyl isocyanate

Well‐defined ω‐cholesteryl poly(n‐hexyl isocyanate) (PHIC–Chol), as well as diblock copolymers of n‐hexyl isocyanate (HIC) with styrene, PS‐b‐PHIC [PS = polystyrene; PHIC = poly(n‐hexyl isocyanate)], and triblock terpolymers with styrene and isoprene, PS‐b‐PI‐b‐PHIC and PI‐b‐PS‐b‐PHIC (PI = polyisoprene), were synthesized with CpTiCl₂(OR) (R = cholesteryl group, PS, or PS‐b‐PI) complexes. The synthetic strategy involved the reaction of the precursor complex CpTiCl₃ with cholesterol or the suitable ω‐hydroxy homopolymer or block copolymer, followed by the polymerization of HIC. The ω‐hydroxy polymers were prepared by the anionic polymerization of the corresponding monomers and the reaction of the living chains with ethylene oxide. The reaction sequence was monitored by size exclusion chromatography, and the final products were characterized by size exclusion chromatography (light scattering and refractive‐index detectors), nuclear magnetic resonance spectroscopy, and, in the case of PHIC–Chol, differential scanning calorimetry. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6503–6514, 2005     

Effect of binary block‐selective solvents on self‐assembly of ABA triblock copolymer in dilute solution

We have studied the self‐assembly of the ABA triblock copolymer (P4VP‐b‐PS‐b‐P4VP) in dilute solution by using binary block‐selective solvents, that is, water and methanol. The triblock copolymer was first dissolved in dioxane to form a homogeneous solution. Subsequently, a given volume of selective solvent was added slowly to the solution to induce self‐assembly of the copolymer. It was found that the copolymer (P4VP₄₃‐b‐PS₃₆₆‐b‐P4VP₄₃) tended to form spherical aggregate or bilayer structure when we used methanol or water as the single selective solvent, respectively. However, the aggregates with various nanostructures were obtained by using mixtures of water and methanol as the block‐selective solvents. The aggregate structure changed from sphere to rod, vesicle, and then to bilayer by changing water content in the block‐selective solvent from 0 to 100%. Moreover, it was found that the vesicle size could be well controlled by changing the copolymer content in the solution. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1536–1545, 2008     

Engineering polymer surfaces with variable chemistry and topography

We describe the preparation of surfaces with controlled surface chemistry and topology combining both surface segregation of block copolymers and “breath figures” formation. For that purpose, an amphiphilic ABC triblock copolymer, that is, poly(2,3,4,5,6‐pentafluorostyrene)‐b‐polystyrene‐b‐poly[poly(ethylene glycol) methyl ether methacrylate] (PS5F₂₁‐b‐PS₃₁‐b‐PPEGMA₃₈) was mixed with high molecular weight polystyrene and spin coated in a moist atmosphere. As demonstrated by X‐ray photoelectron spectroscopy and atomic force microscopy analysis, the surfaces exhibit spherical holes with diameters between 100 and 300 nm. The holes, enriched in triblock copolymer, exhibit variable chemical composition and topography depending on the environmental conditions. The surface functionality could be reversibly modulated: whereas under humid conditions the PPEGMA hydrophilic block reorients towards the surface, annealing to dry air directs the PS5F fluorinated block to the interface. Equally, surfaces annealed to humid air changed their topography from holes to islands depending on the extent of swelling of the PPEGMA block. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2262–2271, 2009     

Strain state of poly(N‐isopropylacrylamide) in polystyrene‐b‐poly(N‐isopropylacrylamide) block copolymers and binary blends with polystyrene

Three diblock copolymers of polystyrene‐b‐poly(N‐isopropylacrylamide) (PS‐b‐PNIPAM) were prepared by reversible addition‐fragmentation chain transfer technique (RAFT) with compositions f_PS = 0.84, f_PS = 0.29, and f_PS = 0.33. Block copolymers rich in PNIPAM were blended with polystyrene and its morphological effects were studied. The morphology of thin films was induced by acetone vapor and determined in the dried state by means of TEM. Copolymers with f_PS = 0.84 and f_PS = 0.29 form hexagonally packed cylinder (HPC) morphologies while that with f_PS = 0.33 corresponds to a lamellar structure. In almost all cases where PNIPAM constitutes the continuous phase, a contraction of the PNIPAM blocks with respect to their average unperturbed dimension was observed, contrary to what one expects from the physics of self‐assembly of block copolymers. In contrast, for HPC morphology where PNIPAM is confined in a PS matrix, both blocks are highly extended. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013 , 51, 1368–1376     

Morphology and deformation behaviour of SBS/PS blends: a combined microscopic and spectroscopic study

Correlation between morphology and micromechanical deformation behaviour of blends consisting of a lamellae-forming linear styrene/butadiene block copolymer and polystyrene homopolymer (hPS) was studied by different microscopic techniques (transmission electron microscopy and scanning electron microscopy) and rheo-optical Fourier transformed infrared spectroscopy. Attributable to a change in morphology from well-ordered lamellae to a distorted one, a transition in deformation mechanism from homogeneous plastic flow of the lamellae to formation of local craze-like deformation zones was observed on addition of hPS. The latter led to a drastic reduction in elongation at break. An abrupt depression in the degree of orientation of the polystyrene (PS) and the polybutadiene (PB) phases in the blends suggested that the failure occurs at the interface between the added hPS and PS blocks of the block copolymer.     

Graphoepitaxial assembly of cylinder forming block copolymers in cylindrical holes

The graphoepitaxial assembly of cylinder‐forming block copolymers assembled into holes is investigated through theoretically informed coarse grained Monte Carlo simulations (TICG MC). The aim is to identify conditions leading to assembly of cylinders that span the entire thickness of the holes, thereby enabling applications in lithography. Three hole geometries are considered, including cylinders, elliptical cylinders, and capsule‐shaped holes. Four distinct morphologies of cylinder forming poly(styrene‐b‐methyl methacrylate) (PS‐b‐PMMA) block copolymers are observed in cylinders and elliptical holes, including cylinders, spheres, partial cylinders, and wall‐bound cylinders. Additional morphologies are observed in capsule‐shaped holes. PMMA cylinders that extend through the entire hole are found with PMMA‐wetting surfaces; a weak wetting condition is needed on the bottom of the hole and a strong wetting condition is necessary on the sides of the hole. Simulated are also used to explore the morphologies that arise when holes are overfilled, or when PMMA homopolymers are added in blends with copolymers. We find that overfilling can alter considerably the morphological behavior of copolymers in cylinders and, for blends; we find that when the homopolymer concentration is >10%, the range of conditions for formation of PMMA cylinders that extend through the entire hole is increased. In general, results from simulations (TICG) are shown to be comparable to those of self‐consistent (SCFT) calculations, except for conditions where fluctuations become important. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 430–441     

Effect of PS‐b‐PCL block copolymer on reaction‐induced phase separation in epoxy/PEI blend

PS‐b‐PCL block copolymer is used to study its influence on the phase evolution of epoxy resin/polyetherimides (PEI) blends cured with methyl tetrahydrophthalic anhydride. The effect of PS‐b‐PCL on the reaction‐induced phase separation of the thermosetting/thermoplastic blends is studied via optical microscopy, scanning electron microscope, and time‐resolved light scattering. The results show that secondary phase separation and typical phase inverted morphologies are obtained in the epoxy/PEI blends with addition of PS‐b‐PCL. It can be attributed to the preferential location of the PS‐b‐PCL in the epoxy‐rich phase, which enhances the viscoelastic effect of epoxy/PEI system and leads to a dynamic asymmetry system between PEI and epoxy. The PS‐b‐PCL block copolymer plays a critical role on the balance of the diffusion and geometrical growth of epoxy molecules. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014 , 52, 1395–1402     

Linear pentablock quintopolymers (l‐SIDMV) with five incompatible blocks: Polystyrene,polyisoprene‐1,4, poly(dimethylsiloxane), poly(tert‐butyl methacrylate), and poly(2‐vinylpyridine)

Three linear pentablock quintopolymers (l‐SIDMV), where S is polystyrene (PS), I polyisoprene‐1,4 (PI), D poly(dimethylsiloxane) (PDMS), M poly(tert‐butyl methacrylate) (PtBuM), and V poly(2‐vinylpyridine) (P2VP), were synthesized by anionic polymerization high vacuum techniques. The approach involves the following: (a) The synthesis of living triblock terpolymer PS‐b‐PI‐b‐PDMSLi and diblock copolymer P2VP‐b‐PtBuMK by sequential polymerizations of the corresponding monomers with sec‐BuLi and benzyl potassium, respectively; and (b) The selective linking of the living triblock terpolymer with the chlorosilane group of 2‐(chloromethylphenyl)ethyldimethylchlorosilane (CMPDMS), followed by linking of the living block copolymer with the remaining chloromethyl group of CMPDMS. Molecular characterization carried out by size exclusion chromatography, membrane osmometry, solution (in CDCl₃ or d₈‐toluene) and solid‐state ¹H‐NMR spectroscopy indicated a high degree of molecular and compositional homogeneity. Differential scanning calorimetry results on the precursors and final polymers were discussed. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3938–3946, 2008     

Surfactant addition effects on dispersion and microdomain orientation in SBS triblock copolymer/alumina nanoparticle composites

The aim of this study was to investigate the effects of surfactant addition on the dispersion of 1–3 wt.% alumina nanoparticles on the self-assembled morphology of poly(styrene-b-butadiene-b-styrene) (SBS) linear triblock copolymer. The neat triblock copolymer microphase separated into PS cylinders self-assembled on a hexagonal array in the PB matrix, being the orientation of domains dependent on the annealing conditions. UV–vis and AFM analyses showed an improvement on dispersion of Al₂O₃ nanoparticles into SBS matrix by adding dodecanethiol as organic surfactant, due to its miscibility with PS block. Interactions between surfactant-coated Al₂O₃ nanoparticles with PS block were demonstrated by the variation on the glass transition temperature of this block. AFM analysis showed that the incorporation of surfactant-coated Al₂O₃ nanoparticles in the SBS matrix have great influence on the orientation of microphase separated domains in SBS nanocomposites.     

Tuning microdomain spacing with light using ortho‐nitrobenzyl‐linked triblock copolymers

Using sequential RAFT polymerization, single monomer insertion, and “click” chemistry, a series of triblock copolymers, poly(ethylene oxide)‐b‐polystyrene‐b‐poly(ethylene oxide), PEO‐b‐PS‐b‐PEO, were synthesized, where one of the two junction points is a UV cleavable ortho‐nitrobenzyl (ONB). Ordered patterns of PEO‐b‐PS‐b‐PEO were produced by solvent vapor annealing. Upon exposure to ultraviolet (UV) light, the PEO‐b‐PS‐b‐PEO was converted into a mixture of a PEO homopolymer and a PS‐b‐PEO diblock copolymer. It was found that the microdomain spacing could be tuned by adjusting the UV exposure time, due to the change in the copolymer architecture and the swelling of the PEO microdomain by the PEO homopolymer produced. By selective area exposure of the PEO‐b‐PS‐b‐PEO thin films, the domain spacing was changed over selected locations across the film, generating patterns of different microdomain sizes. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 355–361.     

Morphology and micromechanical behaviour of styrene/butadiene block copolymers and their blends with polystyrene

The correlation between the morphology and the deformation mechanism in styrene/butadiene block copolymers having modified architecture and in blends with homopolymer polystyrene (hPS) was studied. It was demonstrated that the morphology formation in the block copolymers is highly coupled with their molecular architecture. In particular, the micromechanical behaviour of a star block copolymer and its blends with polystyrene was investigated by using electron microscopy and tensile testing. A homogeneous plastic flow of polystyrene lamellae (thin layer yielding) was observed if the lamella thickness was in the range of 20 nm. The deformation micromechanism switched to the formation of craze-like deformation zones when the average PS lamella thickness changed to about 30 nm and more.     

Synthesis,characterization, and hydrolysis of PVAc-PS-PVAc via charge transfer polymerization

An ABA triblock copolymer of polyvinyl acetate-b-polystyrene-b-polyvinyl acetate (PVAc-PS-PVAc) was successfully synthesized with a binary system composed of polystyrene with N,N-dimethylaniline end groups (PS_da) and benzophenone to initiate the polymerization of vinyl acetate under UV irradiation. The PS_da was obtained by capping the living polystyrene macrodianion with p-(dimethylamino) benzaldehyde in excess. The PVA-PS-PVA could then be obtained by hydrolysis of PVAc-PS-PVAc in the sodium ethoxide benzene solution. The intermediates and desirable copolymers were characterized by GPC, IR, and ¹H-NMR in detail. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2595–2600, 1999     

Thin film confinement reduces compatibility in symmetric ternary block copolymer/homopolymer blends

The thin film phase behavior of ternary blends consisting of symmetric poly(styrene) (PS)-b-poly(dimethylsiloxane)(PDMS), PS, and PDMS was investigated using X-ray reflectivity (XRR) and atomic force microscopy (AFM). This system is strongly segregated, and the homopolymers are approximately the same length as the corresponding blocks of the copolymer. The XRR and AFM data are used to quantify changes in domain spacing (L) and morphology evolution with increasing homopolymer content (Φ _H). In 100 nm thick films, from Φ _H = 0 to 0.20, the system maintains a perfect parallel lamellar structure and domains swell as predicted based on theory; however, from Φ _H = 0.30 to 0.50, a morphology transition to a “dot pattern” morphology (tentatively identified as perforated lamellae) and mixed morphologies were observed before macrophase separation. In thicker films, dot patterns were observed for a broad range of Φ _H before macrophase separation. The absence of the bicontinuous microemulsion phase reported for bulk blends and thin films of perpendicular lamellae and the presence of dot patterns/perforated lamellae are attributed to preferential migration of the PDMS homopolymer to the wetting layers located at the substrate and free air interfaces, which leads to an asymmetric composition within the film and morphology transition. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2018 , 56, 1443–1451     

Stabilization of a cocontinuous phase morphology by a tapered diblock or triblock copolymer in polystyrene‐rich low‐density polyethylene/polystyrene blends

The stability against the thermal annealing of a cocontinuous two‐phase morphology developed in polystyrene (PS)/low‐density polyethylene (LDPE) blends containing 80 wt % PS was investigated. Blends containing 1, 5, and 10 wt % of a tapered diblock poly(styrene‐block‐hydrogenated butadiene) (P(S‐b‐hB)) or triblock poly(styrene‐block‐hydrogenated butadiene‐block‐styrene) (P(S‐hB‐S)) copolymer were melt‐blended with roll‐mill mixing equipment. The efficiency of each of the two copolymers in stabilizing against coalescence the cocontinuous morphology was examined. The tensile properties of the resulting blends, annealed and nonannealed, were also examined in relation to the morphology induced by thermal annealing. The phase morphology was studied by optical and scanning electron microscopy. With computer‐aided image analysis, it was possible to obtain a measurable characteristic parameter to quantify the cocontinuous phase morphology. When it was necessary, the extraction of one phase with a selective solvent was performed. Although the observed differences were subtle, the tapered diblock exhibited a more efficient compatibilizing activity than the triblock copolymer, particularly at a low concentration of about 2 wt %. The superiority of the tapered diblock over the triblock might be due to its ability to quantitatively locate at the LDPE/PS interface and consequently form a more efficient barrier against the subsequent breakup of the elongated structures of the cocontinuous phase morphology. The tensile properties of the triblock‐modified blends were more sensitive to thermal annealing than the tapered‐modified ones. This deficiency was ascribed to the phase morphology coarsening of the dispersed polyethylene phase. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 202–216, 2003     

In situ synthesis of ABA triblock copolymer nanoparticles by seeded RAFT polymerization: Effect of the chain length of the third a block on the triblock copolymer morphology

Synthesis of the ABA triblock copolymer nanoparticles of poly(N,N‐dimethylacrylamide)‐block‐polystyrene‐block‐poly(N,N‐dimethylacrylamide) (PDMA‐b‐PS‐b‐PDMA) by seeded RAFT polymerization is performed, and the effect of the introduced third poly(N,N‐dimethylacrylamide) (PDMA) block on the size and morphology of the PDMA‐b‐PS‐b‐PDMA triblock copolymer nanoparticles is investigated. This seeded RAFT polymerization affords the in situ synthesis of the PDMA‐b‐PS‐b‐PDMA core‐corona nanoparticles, in which the middle solvophobic PS block forms the compacted core, and the first solvophilic PDMA block and the introduced third PDMA block form the solvated complex corona. During the seeded RAFT polymerization, the introduced third PDMA block extends, and the molecular weight of the PDMA‐b‐PS‐b‐PDMA triblock copolymer linearly increases with the monomer conversion. It is found that, the size of the PS core in the PDMA‐b‐PS‐b‐PDMA triblock copolymer core‐corona nanoparticles is almost equal to that in the precursor of the poly(N,N‐dimethylacrylamide)‐block‐polystyrene diblock copolymer core‐corona nanoparticles and it keeps constant during the seeded RAFT polymerization, and whereas the introduction of the third PDMA block leads to a crowded complex corona on the PS core. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1777–1784     

Styrene and isoprene friction factors in styrene–isoprene matrices

Monomeric friction factors, Ξ, for polystyrene (PS), polyisoprene (PI), and a polystyrene–polyisoprene (SI) diblock copolymer have been determined as a function of temperature in four poly(styrene-b-isoprene-b-styrene-b-isoprene) tetrablock copolymer matrices. The Rouse model has been used to calculate the friction factors from tracer diffusion coefficients measured by forced Rayleigh scattering. Within the experimental temperature range the tetrablock copolymers are disordered, allowing for measurement of the diffusion coefficient in matrices with average compositions determined by the tetrablock copolymers (23, 42, 60, and 80% styrene by volume). Remarkably, for a given matrix composition the styrene and isoprene friction factors are essentially equivalent. Furthermore, at a constant interval from the system glass transition temperature, T_g, all of the friction factors (obtained from homopolymer, diblock copolymer, and tetrablock copolymer dynamics) agree to within an order of magnitude. This is in marked contrast to results for miscible polymer blends, where the individual components generally have distinct composition dependences and magnitudes at constant T − T_g. The homopolymer friction factors in the tetrablock matrices were systematically slightly higher than those of the diblock, which in turn were slightly higher than those of the homopolymers in their respective melts, when all compared at constant T − T_g. This is attributed to the local spatial distribution of styrene and isoprene segments in the tetrablocks, which presents a nonuniform free energy surface to the tracer molecules. © 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 3079–3086, 1998     

Synthesis of methyl methacrylate,styrene, and isobutylene multiblock copolymers using atom transfer and cationic polymerization

ABCBA‐type pentablock copolymers of methyl methacrylate, styrene, and isobutylene (IB) were prepared by the cationic polymerization of IB in the presence of the α,ω‐dichloro‐PS‐b‐PMMA‐b‐PS triblock copolymer [where PS is polystyrene and PMMA is poly(methyl methacrylate)] as a macroinitiator in conjunction with diethylaluminum chloride (Et₂AlCl) as a coinitiator. The macroinitiator was prepared by a two‐step copper‐based atom transfer radical polymerization (ATRP). The reaction temperature, ?78 or ?25 °C, significantly affected the IB content in the resulting copolymers; a higher content was obtained at ?78 °C. The formation of the PIB‐b‐PS‐b‐PMMA‐b‐PS‐b‐PIB copolymers (where PIB is polyisobutylene), prepared at ?25 (20.3 mol % IB) or ?78 °C (61.3 mol % IB; rubbery material), with relatively narrow molecular weight distributions provided direct evidence of the presence of labile chlorine atoms at both ends of the macroinitiator capable of initiation of cationic polymerization of IB. One glass‐transition temperature (T_g), 104.5 °C, was observed for the aforementioned triblock copolymer, and the pentablock copolymer containing 61.3 mol % IB showed two well‐defined T_g's: ?73.0 °C for PIB and 95.6 °C for the PS–PMMA blocks. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3823–3830, 2005     

Hybridization of poly(4-vinyl pyridine)-b-polystyrene-b-poly(4-vinyl pyridine) aggregates in dioxane/water solution

Self-assembly of binary blends of two triblock copolymers of poly(4-vinyl pyridine)-b-polystyrene-b-poly(4-vinyl pyridine), i.e., P4VP₄₃-b-PS₂₆₀-b-P4VP₄₃ (P1) and P4VP₄₃-b-PS₃₆₆-b-P4VP₄₃ (P2), in dioxane/water solution was studied. These two triblock copolymers individually tend to form vesicles (P2) and cylindrical micelles (P1) in dilute solution. It was found that copolymer components in the blend, sample preparation method, and annealing time had significant effect on hybridization aggregate morphology. By increasing P1 content in the copolymer blends, fraction of looped and stretched cylinders increased, while fraction of bilayers decreased. Nearly no bilayer was observed when P1 content was above 85 wt%. On the other hand, fraction of cylinders decreased while fraction of bilayers increased with the increase of P2 content in copolymer blends. Lamellar structures were obtained, when P2 content was 60 wt% in the copolymer blends, whereas cylinders were seldom found when P2 content was above 80 wt%. These results indicate that P1 and P2 copolymer molecules cooperatively participate in the formation of cylinders and vesicles. Some exotic structures, such as lamellae with protruding cylinders (LPC), incomplete vesicles with protruding cylinders (VPC), and cylindrical bilayers, have been kinetically trapped. These structures may result from intramicellar fusion processes in cylindrical micelles. The striking structures represent a compromise between bilayer and cylindrical geometries.