Synthesis of Multiblock Copolymers by Coupling Reaction Based

T1 - Synthesis and characterization of model polyisoprene-polylactide diblock copolymers
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Synthesis of Amphiphilic Block Copolymers by Atom …

N2 - Poly(ethylethylene-b-ethylene oxide) (PEE-PEO) diblock copolymers with pyridine-benzoic acid end-groups for heterodimeric hydrogen bonding were designed as a possible means to noncentrosymmetric organizations by spontaneous self-assembly. These end-functionalized polymers were synthesized by anionic living polymerization with protected initiator and terminating reagents. A series of polymeric intermediates with different end-groups was characterized by proton nuclear magnetic resonance, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and gel permeation chromatography. Preliminary studies of solid-state organization by differential scanning calorimetry and small-angle X-ray scattering provided evidence for a long-range order that was sensitive to chain length, copolymer composition, and end-group structure.

These block copolymers can be used as templates to form inorganic nanoparticles.
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There are several ways to synthesize random copolymers

Quantitative replacement of trimethylsilyl groups with boron tribromide in dichloromethane provided an important highly Lewis acidic intermediate that have allowed for the preparation of novel boron containing borate and boronium types of homopolymers and amphiphilic diblock copolymers with different post-polymerization modification processes.

Spherical, cylindrical and lamellar morphologies of these novel diblock copolymers werereported.
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N3 (0.63 g, 0.05 mmol) were introduced into a 100 mL Schlenk flask. The mixture was degassed with several cycles of vacuum pumping and argon purging. Before the click coupling reaction, the solution was stirred at 0 °C for 8 h and then further stirred at 25 °Cf or8ht o make the self-assembly in water possible. The concentrations of both triblock copolymer precursors were 40 mg/ mL, which is sufficiently low in order to avoid a possible intermicelle coupling reaction. The self-assembly assisted click coupling reaction was carried out when the aqueous solution of

T1 - Synthesis of diblock copolymers consisting of hyaluronan and poly(2-ethyl-2-oxazoline)
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Synthesis of Diblock Copolymers With ..

These block copolymers have several glass transition temperatures (equal to the number of dissimilar blocks), and their temperature of flow is determined by the highest temperature of the flow of one of the components.

One-pot synthesis of amphiphilic diblock copolymers …

The combination of properties of homopolymers in a block copolymer manifests itself in the thermomechanical properties and transition temperatures of block copolymers consisting of incompatible or partially compatible polymeric blocks.

One-pot synthesis of amphiphilic diblock copolymers ..

The presence of these microregions is the cause of a significant difference in properties between block copolymers and random copolymers of the same composition, which, in most cases, determines the additivity of structural and mechanical properties of block copolymers.

the synthesis of diblock copolymers by a consecutive ..

The block copolymers are characterised by microphase separation, accompanied by the formation of nano-and microregions with concentration of segments (blocks) having the same chemical structure.

Synthesis of diblock copolymers with cellulose …

However, the correlation between the composition and structure of macromolecules and properties of block copolymers is not easy to define due to difficulties in isolating and identifying individual blocks, which explains the small number of block copolymers with a strictly defined structure among those applied in practice.

Synthesis of Diblock copolymer poly-3 ..

Synthesis of block copolymers significantly expands the possibilities for modifying the properties of polymers, as the macromolecule allows to combine regions of polymers varying in structure and properties: natural and synthetic, carbo- and heterochain, flexible and rigid, hydrophobic and hydrophilic, regular and irregular, etc.