Aggregation behavior of amphiphilic poly(2-alkyl-2-oxazoline) diblock copolymers in aqueous solution studied by fluorescence correlation spectroscopy

The diffusional behavior of amphiphilic poly(2-oxazoline) diblock copolymers in aqueous solution is studied using photon correlation spectroscopy (PCS) and fluorescence correlation spectroscopy (FCS). The polymers were synthesized by living cationic polymerization and were fluorescence-labeled with tetramethyl rhodamine isothiocyanate either at the end of the hydrophilic or the hydrophobic block. Temperature-resolved PCS showed that, at room temperature, large metastable aggregates are present along with unimers and micelles. An annealing above ~40 °C resulted in stable equilibrium micellar solutions. By means of FCS, the hydrodynamic radii of the unimers and the micelles were measured simultaneously in a broad concentration range, and the critical micelle concentration could be determined. Comparison of the results from conventional PCS measurements with this first FCS study showed excellent agreement and the high potential of the FCS technique.Dedicated to Prof. Dr. Erhard W. Fischer on the occasion of his 75th birthdayAn erratum to this article can be found at     

Micellar Behavior of Polystyrene-Poly(Ethylene Oxide) Diblock Copolymers in Aqueous Media: Effect of Copolymer Composition,Temperature, Salt,and Surfactants

Formation and structure of micelles from two amphiphilic polystyrene-block-poly(ethylene oxide) (PS-PEO) diblock copolymers (PS mol.wt. 1000; PEO mol.wt. 3000 and 5000) were examined by surface tension, viscosity, steady state fluorescence, dynamic light scattering (DLS), small angle neutron scattering (SANS), and cryo-transmission electron microscopy (cryo-TEM). The critical micelle concentration (CMC) of the copolymers in aqueous solution was ca. 0.05%; micelle hydrodynamic diameter was 30–35 nm with a narrow size distribution. SANS studies show that the copolymers form ellipsoidal micelles with semi major axis ～23 nm and semi minor axis ～8 nm. No significant change in the structure was found with temperature and presence of salt. The copolymer micelles interaction with the ionic surfactants sodium dodecyl sulphate (SDS) and dodecyltrimethylammonium bromide (DTAB) was also examined by DLS and SANS.     

Synthesis and micellar behavior of poly(vinyl alcohol-<Emphasis Type="Italic">b</Emphasis>-styrene) copolymers containing PVA blocks with different syndiotacticity

Poly(vinyl alcohol-b-styrene) (poly(VA-b-St)) diblock copolymers with different syndiotacticity of poly(vinyl alcohol) (PVA) block were synthesized via consecutive telomerization, atom transfer radical polymerization, and saponification. These amphiphilic block copolymeric micelles were prepared by dialysis against water. Dynamic light scattering and transmission electron micrograph measurements confirmed the formation of a micelles, and the size of a micelle was less than 100 nm and increased with the molecular weight of polystyrene (PS) block. From the fluorescence emission spectrum measurements using pyrene as a fluorescence probe, the copolymers formed micelles with critical micelle concentration (CMC) in the range of 0.125–4.47 mg/l. The CMC values increase with decrease of the molecular weight of the PS block and increase of the syndiotacticity of PVA block. Kinetic stability study of micelles showed increased stability for block copolymers containing PVA block with higher syndiotacticity.     

Aggregation behavior of MPEG‐PCL diblock copolymers in aqueous solutions and morphologies of the aggregates

Poly(ethylene glycol)‐b‐polycaprolactone (MPEG‐PCL) diblock copolymers were synthesized via a ring‐opening polymerization of ε‐CL monomers with MPEG as an initiator. Their solubilities and apparent critical micelle concentrations (CMC) in aqueous solution were investigated as well as the determination of the micellar hydrodynamic diameter using dynamic light scattering (DLS). As PCL block length increased, the solubility and CMC decreased while diameters of micelles increased. The gel–sol transition behaviors were investigated using a vial tilting method. Aqueous solutions of copolymers undergo a gel to sol transition with increase in temperature when their polymer concentrations are above a critical gel concentration (CGC). The CGC of the copolymers and gel–sol transition temperature are influenced by the PCL chain length. The tapping mode AFM was performed by imaging the freeze‐dried deposits from the copolymer solutions on mica to investigate a process from free chains to micelles and to gel. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3406–3417, 2006     

Conductive properties of TiO2/bacterial cellulose hybrid fibres

In this article, we report the first micellization study of amphiphilic copolymers composed of bacterial medium chain length poly(3-hydroxyalkanoates) (mcl-PHAs). A series of diblock copolymers based on fixed poly(ethylene glycol) (PEG) block (5000 g mol(-1)) and a varying poly(3-hydroxyoctanoate-co-3-hydroxyhexanoate) (PHOHHx) segment (1500-7700 g mol(-1)) have been synthesized using "click" chemistry. These copolymers self-assembled to form micelles in aqueous media. The influence of PHOHHx block molar mass on the hydrodynamic size and on the critical micelle concentration (CMC) has been studied using dynamic light scattering and fluorescence spectroscopy, respectively. With increasing PHOHHx length, narrowly distributed micelles with diameters ranging from 44 to 90 nm were obtained, with extremely low CMC (up to 0.85 mg/L). Cryogenic transmission electron microscopy (Cryo-TEM) showed that micelles took on a spherical shape and exhibited narrow polydispersity. Finally, the colloidal stability of the micelles against physiological NaCl concentration has been demonstrated, suggesting they are promising candidates for drug delivery applications.     

Non-surface activity and micellization behavior of cationic amphiphilic block copolymer synthesized by reversible addition-fragmentation chain transfer process

Cationic amphiphilic diblock copolymers of poly(n-butylacrylate)-b-poly(3-(methacryloylamino)propyl)trimethylammonium chloride) (PBA-b-PMAPTAC) with various hydrophobic and hydrophilic chain lengths were synthesized by a reversible addition-fragmentation chain transfer (RAFT) process. Their molecular characteristics such as surface activity/nonactivity were investigated by surface tension measurements and foam formation observation. Their micelle formation behavior and micelle structure were investigated by fluorescence probe technique, static and dynamic light scattering (SLS and DLS), etc., as a function of hydrophilic and hydrophobic chain lengths. The block copolymers were found to be non-surface active because the surface tension of the aqueous solutions did not change with increasing polymer concentration. Critical micelle concentration (cmc) of the polymers could be determined by fluorescence and SLS measurements, which means that these polymers form micelles in bulk solution, although they were non-surface active. Above the cmc, the large blue shift of the emission maximum of N-phenyl-1-naphthylamine (NPN) probe and the low micropolarity value of the pyrene probe in polymer solution indicate the core of the micelle is nonpolar in nature. Also, the high value of the relative intensity of the NPN probe and the fluorescence anisotropy of the 1,6-diphenyl-1,3,5-hexatriene (DPH) probe indicated that the core of the micelle is highly viscous in nature. DLS was used to measure the average hydrodynamic radii and size distribution of the copolymer micelles. The copolymer with the longest PBA block had the poorest water solubility and consequently formed micelles with larger size while having a lower cmc. The "non-surface activity" was confirmed for cationic amphiphilic diblock copolymers in addition to anionic ones studied previously, indicating the universality of non-surface activity nature.     

Self-assembled polypeptide-block-poly(vinylpyrrolidone) as prospective drug-delivery systems

Poly(β-benzyl-l-aspartate)-block-poly(vinylpyrrolidone) diblock copolymers (PAsp(OBzl)-b-PVP) having both hydrophobic and hydrophilic segments of various lengths were synthesized by a combination of ATRP and ROP. These amphiphilic diblock copolymers formed polymeric micelles consisting of a hydrophobic PAsp(OBzl) core and a hydrophilic PVP shell in aqueous solution. The block copolymer was characterized using ¹H NMR and gel permeation chromatography (GPC) analysis. Due to its core–shell structure, this block polymer forms unimolecular micelles in aqueous solutions. The micelle properties of PAsp(OBzl)-b-PVP diblock copolymer were extensively studied by dynamic light scattering (DLS), fluorescence spectroscopy, and transmission electron microscopy (TEM). PAsp(OBzl)-b-PVP copolymers displayed the lowest CMC and demonstrated little cytotoxicity when exposed to SW-1990 pancreatic cancer cells. In order to assess its application in biomedical area, the anti-inflammation drug prednisone acetate was loaded as the model drug in the polymeric nanoparticles. In vitro release behavior of prednisone acetate was investigated, which showed a dramatic responsive fast/slow switching behavior according to the pH-responsive structural changes of a micelle core structure. All of theses features are quite feasible for utilizing it as a novel intelligent drug-delivery system.     

Effect of Hydrophilic/Hydrophobic Block Ratio and Temperature on the Surface and Associative Properties of Oxyethylene and Oxybutylene Diblock Copolymers in Aqueous Media

Recent development in dispersion science and technology demands block copolymers with a variable block length and composition. To highlight that purpose, the surface active, associative, colloidal, and thermodynamic behavior of three diblock copolymers having different hydrophilic to hydrophobic ratio is reported here. Using surface tension and light scattering measurements, the micellization and adsorption behavior of polyoxyethylene and polyoxybutylene diblock copolymers of the type E_mB_n have been analyzed. Critical micelle concentration (CMC) and related thermodynamic parameters like free energy (ΔG_mic), enthalpy (ΔH_mic), and entropy (ΔS_mic) of micellization were calculated from CMC value using the closed association model. Likewise, the surface active parameters, like surface excess concentration (Γ₂), area per molecule (A₂), and thermodynamic parameters such as free energy (ΔG_ads), enthalpy (ΔH_ads), and entropy (ΔS_ads) of adsorption of polymer at the air/water interface, were also calculated at various temperatures. Static and dynamic light scattering techniques were employed for the determination of the weight-average molar (M_w), association number (N_w), polymer–water interaction (A₂), and micellar size in terms of hydrodynamic radii (R_h) of copolymer micelles. The effect of block length and solution temperature on the surface and micellar properties of these copolymers was also investigated.     

Fluorescence correlation spectroscopy in colloid and interface science

In the last two decades fluorescence correlation spectroscopy (FCS) has been increasingly applied to analyze systems and processes relevant to colloid and interface science. The method has become a routine tool to measure the hydrodynamic radii of small fluorescent molecules, macromolecules and nanoparticles, characterize their interactions and follow a possible aggregation. It was also used to study the diffusion of such species in inhomogeneous media like polymer melts, solutions, gels or porous structures. The formation kinetics and size of micelles of surfactants or block copolymers has been quantified. FCS has also been applied to characterize diffusion of tracers at fluid–liquid and solid–liquid interfaces and study the hydrodynamic boundary condition. The review is intended to summarize these applications and highlight perspectives but also limits of FCS in colloid and interface science.     

Synthesis and Self‐Assembly of Thermoresponsive Amphiphilic Biodegradable Polypeptide/Poly(ethyl ethylene phosphate) Block Copolymers

We report the design and synthesis of new fully biodegradable thermoresponsive amphiphilic poly(γ‐benzyl L ‐glutamate)/poly(ethyl ethylene phosphate) (PBLG‐b‐PEEP) block copolymers by ring‐opening polymerization of N‐carboxy‐γ‐benzyl L ‐glutamate anhydride (BLG? NCA) with amine‐terminated poly(ethyl ethylene phosphate) (H₂N? PEEP) as a macroinitiator. The fluorescence technique demonstrated that the block copolymers could form micelles composed of a hydrophobic core and a hydrophilic shell in aqueous solution. The morphology of the micelles as determined by transmission electron microscopy (TEM) was spherical. The size and critical micelle concentration (CMC) values of the micelles showed a decreasing trend as the PBLG segment increased. However, UV/Vis measurements showed that these block copolymers exhibited a reproducible temperature‐responsive behavior with a lower critical solution temperature (LCST) that could be tuned by the block composition and the concentration.     

Chitooligosaccharide Copolymers: Synthesis and Aqueous Self-assembly

Novel water-soluble amphiphilic graft copolymers (COS-g-PCL-b-MPEG) were synthesized by the coupling reaction between chitooligosaccharide (COS) and MPEG-b-PCL-COOH, which was synthesized via ring-opening polymerization of ε-caprolactone (CL) using MPEG as an initiator and subsequent carboxylation by succinic anhydride. The chemical composition of the graft copolymers was confirmed by ¹H-NMR spectra and FT-IR spectrometry. The thermal properties and crystallinity of the copolymers were observed by DSC and XRD measurements, which showed the existence of separate backbone and graft chain phases in the copolymer. The micellar behavior via self-assembly of the graft copolymers in aqueous solution was studied using pyrene fluorescence dye technique. AFM measurements showed that the micelles had a spherical morphology at the critical micelle concentration (CMC) and ranged in size from 20–45 nm. The amphiphilic ternary biodegradable graft copolymer endows the hydrophilic outer shell of micelles with structural and functional diversification, which might be desirable for drug delivery applications.     

Amphiphilic diblock copolymers bearing pendant aromatic acetal groups: Synthesis and tunable pH‐triggered assembly/disassembly transition behavior

A novel aromatic acetal‐based acid‐labile monomer 2‐phenyl‐5‐ethyl‐5‐acryloxymethyl‐1,3‐dioxacyclohexane (HEDPA) was synthesized and polymerized by reversible addition fragmentation chain transfer (RAFT) polymerization using alkynyl functional chain transfer agent (CTA‐Alk). Afterward, a series of amphiphilic diblock copolymers composed of fixed hydrophobic poly(2‐phenyl‐5‐ethyl‐5‐acryloxymethyl‐1,3‐dioxacyclohexane) (PDAEP) segments and various lengths of hydrophilic mPEG segments were prepared through click reaction between alkynyl‐terminated PDAEP and azido‐terminated mPEG. The self‐assembly behaviors of the diblock copolymers were investigated by dynamic light scattering (DLS), transmission electron microscopy (TEM), fluorescence spectroscopy, and ¹H NMR. These results indicated that the diblock copolymers could self‐assemble into nano‐sized micelles with PDAEP cores and PEG coronas in aqueous solution. DLS, fluorescence spectroscopy and UV–vis spectroscopy were used to monitor the pH‐triggered assembly/disassembly transition of the micelles. These results showed that the assembly/disassembly transition behaviors of the diblock copolymers micelles can be adjusted by changing the lengths of the mPEG segments. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1537–1547     

Novel fluoroalkyl end-capped amphiphilic diblock copolymers with pH/temperature response and self-assembly behavior

A series of fluoroalkyl end-capped diblock copolymers of poly[2-(N,N-dimethylamino)ethyl methacrylate] (PDMAEMA or PDMA) and poly[2-(N,N-diethylamino)ethyl methacrylate] (PDEAEMA or PDEA) have been synthesized via oxyanion-initiated polymerization, in which a potassium alcoholate of 4,4,5,5,6,6,7,7,7-nonafluoro-1-heptanol (NFHOK) was used as an initiator. The chemical structures of the NFHO-PDMA-b-PDEA and NFHO-PDEA-b-PDMA depended on the addition sequence of the two monomers and the feeding molar ratios of [DMA] to [DEA] during the polymerization process. These copolymers have been characterized by (1)H NMR and (19)F NMR spectroscopy and gel permeation chromatography (GPC). The aggregation behavior of these copolymers in aqueous solutions at different pH media was studied using a combination of surface tension, fluorescence probe, and transmission electron microscopy (TEM). Both diblock copolymers exhibited distinct pH/temperature-responsive properties. The critical aggregation concentrations (cacs) of these copolymers have been investigated, and the results showed that these copolymers possess excellent surface activity. Besides, these fluoroalkyl end-capped diblock copolymers showed pH-induced lower critical solution temperatures (LCSTs) in water. TEM analysis indicated that the NFHO-PDMA(30)-b-PDEA(10) diblock copolymers can self-assemble into the multicompartment micelles in aqueous solutions under basic conditions, in which the pH value is higher than the pKa values of both PDMA and PDEA homopolymers, while the NFHO-PDEA(10)-b-PDMA(30) diblock copolymers can form flowerlike micelles in basic aqueous solution.     

Amphiphilic diblock copolymers based on poly(2‐ethyl‐2‐oxazoline) and poly(4‐substituted‐ε‐caprolactone): Synthesis,characterization, and cellular uptake

Amphiphilic diblock copolymers with various block compositions were synthesized on poly(2‐ethyl‐2‐oxazoline) (PEtOz) as a hydrophilic block and poly(4‐methyl‐ε‐caprolactone) (PMCL) or poly(4‐phenyl‐ε‐caprolactone) (PBCL) as a hydrophobic block. These PEtOz‐b‐PMCL and PEtOz‐b‐PBCL copolymers consisting of soft domains of amorphous PEtOz and PM(B)CL had no melting endothermal peaks but displayed T_g. The lower critical solution temperature (LCST) values for the PEtOz‐b‐PMCL, and the PEtOz‐b‐PBCL aqueous solution were observed to shift to lower temperature than PEtOz homopolymers. Their aqueous solutions were characterized using fluorescence techniques and dynamic light scattering (DLS). The block copolymers formed micelles with critical micelle concentrations (CMCs) in the range 0.6–11.1 mg L^?1 in an aqueous phase. As the length of the hydrophobic PMCL or PBCL blocks elongated, lower CMC values were generated. The mean diameters of the micelles were between 127 and 318 nm, with PDI in the range of 0.06–0.21, suggesting nearly monodisperse size distributions. The drug entrapment efficiency and drug‐loading content of micelles depend on block polymer compositions. In vitro cell viability assay showed that PEtOz‐b‐PMCL has low cytotoxicity. Doxorubicin hydrochloride (DOX)‐loaded micelles facilitated human cervical cancer (HeLa) cell uptake of DOX; uptake was completed within 2 h, and DOX was able to reach intracellular compartments and enter the nuclei by endocytosis. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2769–2781     

Solution behavior of linear-dendritic rod diblock copolymers in methanol

The solution behavior of spherical dendrimers as well as hybrid-linear dendritic diblock copolymers has been extensively studied, and the size, shape, and ability of these polymers to encapsulate small molecules have led to their comparison with traditional micelles. We have recently reported the synthesis of a new dendritic copolymer architecture, the linear-dendritic rod diblock copolymer, and in this work, we examine the solution behavior of these unique polymers in methanol at 25 degrees C, using dynamic light scattering and intrinsic viscosity measurements. The diblock copolymers consist of a linear poly(ethylene oxide)-poly(ethylene imine) diblock copolymer backbone around which poly(amido amine) branches have been divergently synthesized from the poly(ethylene imine) block. The hydrodynamic radii and the viscometric radii of the polymers were found to increase slowly with increasing generation up to generation 3.5; however, after generation 3.5, the radii were found to increase very rapidly. This increase can be explained by an elongation of the dendritic block into a more rodlike configuration and a corresponding breakdown of the spherical approximation used to calculate the radii. The intrinsic viscosity of the amine and ester terminated polymers was found to follow two very different trends at low generation; however, at higher generations, they followed similar, yet slightly different, curves with the values for the amine terminated polymers only a little larger than those of the ester terminated polymers. At low generations, the chemistry of the end groups and its interaction with the solvent were found to be more important, whereas at higher generations, the highly branched nature of the dendritic block was the more important factor. For the ester terminated polymers, a maximum in the intrinsic viscosity occurred at generation 1.5. Since this maximum occurred at a much lower generation number than is traditionally seen for spherical dendrimers, new scaling relations for the intrinsic viscosity of dendritic rod polymers were developed and were found to support this observation. A minimum in the intrinsic viscosity was also observed at generation 3.5 for the ester terminated polymers and a minimum or leveling off in the intrinsic viscosity at generation 4.0 was found for the amine terminated polymers, which can be attributed to the transitioning of the polymers to a more elongated, rodlike shape and the increased influence of the shape factor on the intrinsic viscosity.     

Mixed micelles based on cationic and anionic amphiphilic diblock copolymers containing identical hydrophobic blocks

Through the use of the methods of turbidimetry, UV spectrophotometry, fluorescence spectroscopy, dynamic light scattering, and ultracentrifugation, micelle formation is studied for cationic (polysty-rene-poly-N-ethyl-4-vinylpyridium bromide) and anionic (polystyrene-sodium polyacrylate) diblock copolymers containing identical polystyrene blocks in dilute aqueous saline solutions. Mixing of aqueous dispersions of individual micelles is accompanied by the formation of only insoluble products, which likely are intermicellar interpolyelectrolyte complexes. At the same time, mixing of diblock copolymers in a nonselective solvent and its subsequent gradient replacement with water during suppressed interpolyelectrolyte interactions yields mixed diblock copolymer micelles, which are found to be dispersionally stable in an excess of charged units of any polymer component. The micelles are composed of an insoluble polystyrene core and a mixed interpolyelectrolyte corona, and their hydrodynamic characteristics are controlled by the ratio of charged units in the mixed diblock copolymers. The mixed micelles are found to be able to interact with the macromolecules of a homopolyelectrolyte, sodium poly(styrene sulfonate), in aqueous solutions and form ternary complexes. In this case, depending on the composition of the mixed micelles, ternary complexes can be dispersionally stable or can aggregate and precipitate.     

Synthesis and micellar behavior of poly(acrylic acid-b-styrene) block copolymers

Poly(acrylic acid-b-styrene) (PAA-b-PS) amphiphilic block copolymers were synthesized by consecutive telomerization of tert-butyl acrylate, atom transfer radical polymerization (ATRP) of styrene, and hydrolysis. The resulting block copolymers were characterized by ¹H NMR and GPC. These amphiphilic block copolymeric micelles were prepared by dialysis against water. Transmission electron micrograph (TEM) and laser particle sizer measurements were used to determine the morphology and size of these micelles. The results showed that these amphiphilic block copolymers formed spherical micelles with average size of 140–190?nm. The critical micelle concentration (CMC) and the kinetic stability of these micelles were investigated by fluorescence technique, using pyrene as a fluorescence probe. The observed CMC value was in the range of 0.075–0.351?mg/L. Kinetic stability studies showed that the stability of micelles increased with the decrease of the pH value of the solution.     

Nanosized Micelles Self-Assembled from amphiphilic dextran-graft-methoxypolyethylene glycol/poly(ε-caprolactone) copolymers

A series of amphiphilic copolymers, dextran-graft-methoxypolyethylene glycol/poly(ε-caprolactone) (Dex-g-mPEG/PCL) were synthesized by grafting both PCL and mPEG chains to dextran, and subsequently the micellar self-assembly behavior of resultant copolymers was investigated. PCL was designed by using Fmoc-protected valine other than organometallic catalyst as the initiator to ring-opening polymerize ε-caprolactone (CL) in view of the safety demand as well as the extra application potential resulting from -NH₂ group introduced after Fmoc deprotection. All the copolymers were characterized by ¹H NMR, FT-IR and GPC measurements. The prepared copolymers are capable of self-assembling into nanosized spherical micelles in aqueous solution with the diameter of around 100-200 nm determined by TEM image and DLS measurement. The critical micellar concentration (CMC) of the graft copolymers is in the range of 10-100 mg/L determined by the fluorescence robe technique using pyrene. The result also indicated that the CMC of self-assembled micelles could be adjusted by controlling the degree of substitution of mPEG and PCL, and these micelles may find great potential as drug carriers in biomedical fields.     

Self-association dynamics and morphology of short polymeric PBA-b/co-PAA surfactants

The self-association characteristics of very short and well-defined poly(butyl acrylate)-b-poly(acrylic acid) (PBA-b-PAA) block copolymers in water have been studied. The diblocks are asymmetric with the PBA block longer than the PAA block, giving rise to hollow sphere morphology. This is affirmed by experimental data and theoretical evaluations of the hydrophilic and hydrophobic domain sizes, as well as a value close to 1 for the ratio of the hydrodynamic to the gyration radius of the micelles. Besides, the untypically short PBA blocks (polymerization number around 15) render the micelles dynamic. Indications in support include among others the following: the CMC (critical micellar concentration) values depend, together with the aggregation numbers and the micellar sizes, on the block lengths, as predicted by theory; above the CMC their sizes are concentration-independent, while the micelles disappear below CMC. A comparison was also made with a random PBA-co-PAA copolymer of similar length, which self-associates at an apparent CMC 1 order of magnitude larger than those of the block copolymers, but the size of the formed micelles depends on the concentration.     

Novel thermoresponsive block copolymers having different architectures—structural,rheological, thermal,and dielectric investigations

Thermoresponsive block copolymers comprising long, hydrophilic, nonionic poly(methoxy diethylene glycol acrylate) (PMDEGA) blocks and short hydrophobic polystyrene (PS) blocks are investigated in aqueous solution. Various architectures, namely diblock, triblock, and starblock copolymers are studied as well as a PMDEGA homopolymer as reference, over a wide concentration range. For specific characterization methods, polymers were labeled, either by partial deuteration (for neutron scattering studies) or by fluorophores. Using fluorescence correlation spectroscopy, critical micellization concentrations are identified and the hydrodynamic radii of the micelles, r _h ^mic , are determined. Using dynamic light scattering, the behavior of r _h ^mic in dependence on temperature and the cloud points are measured. Small-angle neutron scattering enabled the detailed structural investigation of the micelles and their aggregates below and above the cloud point. Viscosity measurements are carried out to determine the activation energies in dependence on the molecular architecture. Differential scanning calorimetry at high polymer concentration reveals the glass transition of the polymers, the fraction of uncrystallized water and effects of the phase transition at the cloud point. Dielectric relaxation spectroscopy shows that the polarization changes reversibly at the cloud point, which reflects the formation of large aggregates upon heating through the cloud point and their redissolution upon cooling.