RANDOM COPOLYMER OF PROPYLENE OXIDE AND ETHYLENE OXIDE PREPARED BY DOUBLE METAL CYANIDE COMPLEX CATA

来源 :Chinese Journal of Polymer Science | 被引量 : 0次 | 上传用户:jianxiaxjb
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Copolymerization of propylene oxide (PO) and ethylene oxide (EO) using double metal cyanide (DMC) complexas the catalyst was carried out. The structure of random copolymers was confirmed by ~(13)C-NMR and IR spectra. ~1H-NMRanalysis shows that the EO content in the copolymer is the same as that in the initial monomer feed. Moderate molecularweight copolymers with various EO content were obtained and their values of molecular weigh distribution (MWD) fell inthe range of 1.21-1.55. It was found that the molecular weight of copolymers is controlled by the mass ratio of EO + PO toinitiator moles used. The reaction rate as well as polymer yield decrease with increasing EO content in the feed composition. Copolymerization of propylene oxide (PO) and ethylene oxide (EO) using double metal cyanide (DMC) complexas the catalyst was carried out. The structure of random copolymers was confirmed by C-NMR and IR spectra. shows that the EO content in the copolymer is the same as that that in the initial monomer feed. Moderate molecular weight copolymers with various EO content were obtained and their values ​​of molecular weigh distribution (MWD) fell inthe range of 1.21-1.55. It was found that the molecular weight of the copolymer is controlled by the mass ratio of EO + PO toinitiator moles used. The reaction rate as well as polymer yield decrease with increasing EO content in the feed composition.
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