Synthesis and Properties of Hydrophilic Networks Based on Poly(ethylene glycol) and β‐Cyclodextrin

Abstract

New hydrophilic networks combining poly(ethylene glycol) (PEG) and β‐cyclodextrin (β‐CD) have been prepared. Both components are linked by reacting PEG chains previously end‐capped with isocyanate groups and β‐CD, forming urethane links. Networks of molar compositions (β‐CD/PEG) ranging from 1/4 to 1/14, and with four different molar masses (400, 600, 900, and 1 350 g · mol−1) of the end‐capped PEG precursor have been synthesized. The networks have good thermal stability and low glass transition temperatures. Crystallinity has only been detected for the two higher molar mass PEG precursors. The swelling properties of these hydrogels depend on the chain lengths of the PEG precursor and also on the temperatures.

Sorption of 1–Naphthol on –Cyclodextrin–Poly(ethylene Glycol) hydrogels

“…This fact, coupled with its chemical and thermal stability, and good mechanical properties, as has been reported in previous works 8,9 makes them interesting materials for removing organic contaminants from water. Number: MAT2010-21509-CO3) and Gobierno Vasco (Grupos consolidados) to whom researches are gratefully acknowledged.…”

“…Synthesis and characterization of the cyclodextrin hydrogels used as sorbent materials have been described in a previous paper 9 . Briefly, commercial samples of poly(ethylene glycol) (PEG) (Aldrich) with different molar masses (400, 600 and 900 g/mol) are end-caped with isocyanate groups by using a diisocyanate reagent (hexamethylene diisocyanate) in N,Ndimethylformamide as solvent at 328 K and dibutyltin dilaurate as catalyst.…”

“…Recently, our group has developed a new type of hydrogels containing -CD by using as crosslinking agent a modified Poly(ethylene glycol) (PEG): poly(ethylene glycol) end-capped with a diisocyanate 8,9 . The reaction between the chains of the modified PEG and the hydroxyl groups of cyclodextrin rings leads to the formation of a network with urethane bonds.…”

Swelling and Diffusion Characteristics of Hydrogels Synthesized from Diepoxy-terminated Poly(ethylene glycol)s and Aliphatic Polyamines

“…The diffusion exponent n was always higher for DEPEG 2000 -and DEPEG 4000 -based hydrogels than for their lower MW counterparts, which indicates that in the case of higher MW PEG hydrogels the ratio rate of polymer chain relaxation/rate of solvent diffusion is smaller than for hydrogels with shorter chains. This may be explained through the semicrystalline character of the PEG-based hydrogels (19,30,37). As previously shown, PEG 600 -and PEG 1000 -based xerogels display a melting temperature (T m ) below or around room temperature, while for those containing PEG 2000 and PEG 4000 chains it was above 40°C (19).…”

Synthesis and Characterization of Linear and Cross-Linked Cyclodextrin Polyurethane Elastomers

“…Due to the hydrophilic character of the main components, the final result is a hydrophilic polyurethane network based on poly(ethylene glycol) and b-cyclodextrin exhibiting good properties [25,26] .…”