## SYNOPSIS Blends of poly(L-lactide) (PLLA) and poly(e-caprolactone) (PCL) were prepared in a corotating twin screw miniextruder (40 rpm, 200"). It was attempted to prepare multiblock copolymers by allowing a controlled number of transesterification reactions. Various catalysts (n-Bu,SnOMe, Sn(Oc
Preparation and permeability of a block copolymer dialysis membrane by poly(γ-methyl-L-glutamate) and poly(ethylene glycol)
✍ Scribed by Yue-E Fang; Xia Zhao
- Publisher
- John Wiley and Sons
- Year
- 1998
- Tongue
- English
- Weight
- 230 KB
- Volume
- 68
- Category
- Article
- ISSN
- 0021-8995
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✦ Synopsis
The block copolymer (PMLG-b-PEG) of poly( g-methyl-L-glutamate) (PMLG) and isocyanate-terminated poly(ethylene glycol) was synthesized. Membranes were prepared by casting 2% 1,2-dichloroethane solutions of the polymer onto a glass plate and by evaporating the solvent at room temperature. The structure and microdomain morphologies of the membranes were observed with IR spectroscopy and scanning electron microscopy, respectively. Measurement of the contact angles of deionized water on polymer membrane surfaces was made. The mechanical properties of the membranes were also determined. The permeability of the PMLG-b-PEG and PMLG membranes toward urea and creatinine was studied in a dialyzer. In all cases, the block membranes showed improved permeability toward those solutes in comparison with the PMLG membranes. The permeation coefficients of urea, through the PMLG-b-PEG300 and PMLG-b-PEG1000 membranes, were about 2.3 and 3.2 times larger than that of PMLG membranes, and for creatinine through PMLG-b-PEG300 and PMLG-b-PEG1000 membranes, were about 1.0 and 2.0 times larger than that of PMLG membranes.
📜 SIMILAR VOLUMES
Poly(D,L-lactide) -poly(1-caprolactone) -poly(ethylene glycol) -poly(1-caprolactone) -poly (D,L-lactide) block copolymer (PLA-PCL-PEG-PCL-PLA) was prepared by copolymerization of 1-caprolactone (1-CL) and D,L-lactide (D,L-LA) initiated by potassium poly(ethylene glycol)ate in THF at 25ЊC. The copoly