Synthesis and Properties of Biodegradable ABA Triblock Copolymers of Polylactide (A) and Polyethylene Glycol (B)

The triblock ABA copolymers of poly (D,L-lactide)-b-poly (ethylene glycol)-b-poly (D,L-lactide) (PDLLA-PEG-PDLLA) were synthesized by bulk ring-opening polymerization in the presence of N2 under normal pressure, using the D,L-lactide (DLLA) as monomer, hydroxyl endgroups of poly(ethylene glycol) (PEG) as initiator and the stannous octoate as the catalyst. The resulting copolymers were characterized by various analytical techniques. Effects of molar ratios of lactide to PEG and the chain length of PEG on the viscosity-average molecular weight of the copolymers, the biodegradation behaviors and hydrophilicity of the copolymers were investigated in detail. The results showed that the viscosity-average molecular weight and the contact angle of the copolymers increased with the molar ratio of lactide to PEG, but water uptake and degradability decreased.

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Some Guidelines for the Synthesis and Melting Characterization of Azide Poly(ethylene glycol) Derivatives

Polymers ◽

10.3390/polym12061269 ◽

2020 ◽

Vol 12 (6) ◽

pp. 1269

Author(s):

Daniel González-Fernández ◽

Mercedes Torneiro ◽

Massimo Lazzari

Keyword(s):

Molecular Weight ◽

Ethylene Glycol ◽

Average Molecular Weight ◽

Size Exclusion ◽

Degree Of Crystallinity ◽

Specific Class ◽

Poly Ethylene Glycol ◽

End Groups ◽

Poly Ethylene

We provide fundamental guidelines in the form of a tutorial to be taken into account for the preparation and characterization of a specific class of poly(ethylene glycol) (PEG) derivatives, namely azide-terminated PEGs. Special attention is given to the effect of these chain end groups and their precursors on properties affecting the PEGylation of proteins, nanoparticles and nanostructured surfaces. Notwithstanding the presence of 13C satellite peaks, we show that 1H NMR enables not only the routine quantitative determination of chain-end substitution, but is also a unique method to calculate the absolute number average molecular weight of PEG derivatives. In the use of size exclusion chromatography to get molecular weight distributions, we highlight the importance of distinguishing between eventual secondary reactions involving molecular weight changes and the formation of PEG complexes due to residual amounts of metal cations from reactants. Finally, we show that azide end groups affect PEG melting behavior. In contrast to oxygen-containing end groups, azides do not interact with PEG segments, thus inducing defect formation in the crystal lattice and the reduction of crystal sizes. Melting temperature and degree of crystallinity decrease become especially relevant for PEGs with very low molecular weight, and its comprehension is particularly important for solid-state applications.

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Mannosylated brush copolymers based on poly(ethylene glycol) and poly(ε-caprolactone) as multivalent lectin-binding nanomaterials

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.10.212 ◽

2019 ◽

Vol 10 ◽

pp. 2192-2206 ◽

Cited By ~ 2

Author(s):

Stefania Ordanini ◽

Wanda Celentano ◽

Anna Bernardi ◽

Francesco Cellesi

Keyword(s):

Molecular Weight ◽

Ethylene Glycol ◽

Ring Opening ◽

Binding Assay ◽

Lectin Binding ◽

Aqueous Media ◽

Poly Ethylene Glycol ◽

High Control ◽

Poly Ethylene ◽

Macromolecular Architecture

A class of linear and four-arm mannosylated brush copolymers based on poly(ethylene glycol) and poly(ε-caprolactone) is presented here. The synthesis through ring-opening and atom transfer radical polymerizations provided high control over molecular weight and functionality. A post-polymerization azide–alkyne cycloaddition allowed for the formation of glycopolymers with different mannose valencies (1, 2, 4, and 8). In aqueous media, these macromolecules formed nanoparticles that were able to bind lectins, as investigated by concanavalin A binding assay. The results indicate that carbohydrate–lectin interactions can be tuned by the macromolecular architecture and functionality, hence the importance of these macromolecular properties in the design of targeted anti-pathogenic nanomaterials.

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Synthesis and Characterizations of Biobased Copolymer Poly(ethylene-co-butylene 2,5-Furandicarboxylate)

International Journal of Polymer Science ◽

10.1155/2021/9104546 ◽

2021 ◽

Vol 2021 ◽

pp. 1-8

Author(s):

Nam Vu Trung ◽

Mai Ngoc Nguyen ◽

Anh Nguyen Thi Ngoc ◽

Ni Pham Thi ◽

Tung Tran Quang ◽

...

Keyword(s):

Molecular Weight ◽

Ethylene Glycol ◽

Structural Characterization ◽

Average Molecular Weight ◽

Step Process ◽

Molar Ratios ◽

Furandicarboxylic Acid ◽

Poly Ethylene ◽

Copolymer Poly

Homopolymers and copolymers derived from 2,5-furandicarboxylic acid have been extensively studied for their potential in the development of sustainable plastics. This research definitely spotlighted the synthesis of poly(ethylene-co-butylene 2,5-furandicarboxylate) copolymer via the two-step melting polycondensation with various ethylene glycol/1,4-butanediol molar ratios. The structural characterization of the obtained biobased copolymer was carried out by ATR-FTIR and 1H NMR. The average molecular weight of the obtained copolymer was determined by the intrinsic viscosity measurements. It was found that ethylene glycol was preferentially incorporated into the copolymer structures when the molecular weight of the products was not high enough (>18000). The decomposition of two types of monomer units of the obtained copolymer was proven through the degradation two-step process by TGA measurements.

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Preparation and swelling behavior of end-linked hydrogels prepared from linear poly(ethylene glycol) and dendrimer-star polymers

Journal of Polymer Engineering ◽

10.1515/polyeng-2020-0220 ◽

2021 ◽

Vol 41 (3) ◽

pp. 202-210

Author(s):

Jun Wang ◽

Guangna Qu ◽

Xiangbin Liu ◽

Qin Yu ◽

Na Zhang

Keyword(s):

Molecular Weight ◽

Ethylene Glycol ◽

Swelling Behavior ◽

Star Polymer ◽

Molar Ratio ◽

Solution Temperature ◽

Poly Ethylene Glycol ◽

Dsc Measurements ◽

Poly Ethylene ◽

Epoxy Groups

Abstract Linear diepoxide-terminated poly(ethylene glycol) (PEG) of molar mass 600, 1000 and 2000 g mol−1 was end-linked with dendrimer-star polymer (PAMAM) of generations 1.0 in water to prepare architecturally well-defined copolymer hydrogels. The structures and properties of the products were characterized using infrared, 1H NMR, DSC measurements, scanning electron microscopy (SEM) and swelling behavior tests. The swelling behavior of these hydrogels was tested in distilled water at constant temperature and the equilibrium swelling ratio (ESR) was determined for structurally different hydrogels and various environmental conditions, which showed that ESR was influenced by the molecular weight of PEG, the molar ratio of H amine groups/epoxy groups, temperature and pH. Higher ESR was obtained for either longer-chain PEG, non-stoichiometric H amine/epoxy groups ratio, acidic pH or lower temperatures. When the hydrogel was switched from 10 °C to 65 °C and pH 3.5 to 11.5, the swelling behavior of the hydrogels showed good reversibility for swelling–deswelling. When the molecular weight of PEG was changed in the range of 600–2000, the lower critical solution temperature (LCST) of hydrogel increased from 30 to 40 °C. When the molar ratio of H amine/epoxy groups was changed, the LCST was not significantly changed.

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Fractionation and molecular weight determination of poly(ethylene glycol methacrylate)

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19684104 ◽

1968 ◽

Vol 33 (12) ◽

pp. 4104-4110 ◽

Cited By ~ 16

Author(s):

M. Bohdanecký ◽

Z. Tuzar ◽

M. Štoll ◽

R. Chromeček

Keyword(s):

Molecular Weight ◽

Ethylene Glycol ◽

Molecular Weight Determination ◽

Poly Ethylene Glycol ◽

Glycol Methacrylate ◽

Poly Ethylene

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Poly(ethylene glycol)-b-poly(1,3-trimethylene carbonate) Amphiphilic Copolymers for Long-Acting Injectables: Synthesis, Non-Acylating Performance and In Vivo Degradation

Molecules ◽

10.3390/molecules26051438 ◽

2021 ◽

Vol 26 (5) ◽

pp. 1438

Author(s):

Silvio Curia ◽

Feifei Ng ◽

Marie-Emérentienne Cagnon ◽

Victor Nicoulin ◽

Adolfo Lopez-Noriega

Keyword(s):

Ethylene Glycol ◽

Ring Opening ◽

Gel Chromatography ◽

Amphiphilic Copolymers ◽

Trimethylene Carbonate ◽

Poly Ethylene Glycol ◽

Poly Ethylene ◽

Long Acting ◽

In Vivo Degradation

This article presents the evaluation of diblock and triblock poly(ethylene glycol)-b-poly(1,3-trimethylene carbonate) amphiphilic copolymers (PEG-PTMCs) as excipients for the formulation of long-acting injectables (LAIs). Copolymers were successfully synthesised through bulk ring-opening polymerisation. The concomitant formation of PTMC homopolymer could not be avoided irrespective of the catalyst amount, but the by-product could easily be removed by gel chromatography. Pure PEG-PTMCs undergo faster erosion in vivo than their corresponding homopolymer. Furthermore, these copolymers show outstanding stability compared to their polyester analogues when formulated with amine-containing reactive drugs, which makes them particularly suitable as LAIs for the sustained release of drugs susceptible to acylation.

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