二维核磁共振法研究线型聚乙二醇与树枝状聚苄醚形成的三嵌段共聚物

2D NMR EVIDENCE OF FORMATION OF TRIBLOCK COPOLYMERS OF COIL POLY(ETHYLENE GLYCOL) WITH TWO DENDRITIC POLY(BENZYL ETHER) BLOCKS

Tri-block amphiphilic copolymers with hybrid architectures were synthesized by coupling linear （poly（ethylene） glycol）（PEG） and dendritic second-generation Fréchet-type poly（benzyl ether）（PBE） via the Williamson reaction （Gisotv,et al. Angew Chem,Int Ed Engl,1992,31:1200～1202）.Our experimental study shows that the powerful two-dimensional （）1H- （）13C heteronuclear multiple-quantum correlation （HMQC） and two-dimensional （）1H- （）13C heteronuclear multiple-bond correlation （HMBC） NMR techniques rather than the classical one-dimensional （）1H and （）13C-NMR methods can provide clear evidence to verify the formation of the tri-block copolymers.In our measurements HMQC and HMBC NMR techniques directly detected the signal of ether bonds bridged in-between PBE dendrons and PEG blocks,therefore,the formation of the block copolymers are evidently confirmed in molecular level.This work also provides a general method to exactly confirm the formation of block copolymers.

Tri-block amphiphilic copolymers with hybrid architectures were synthesized by coupling linear poly(ethylene glycol) ( PEG) and dendritic second-generation Frechet-type poly ( benzyl ether) (PBE) via the Williamson reaction (Gisotv, et al. Angew Chem, Int Ed Engl, 1992, 31: 1200similar to1202). Our experimental study shows that the powerful two-dimensional H-1-C-13 heteronuclear multiple-quantum correlation ( HMQC) and two-dimensional H-1-C-13 heteronuclear multiple-bond correlation (HMBC) NMR techniques rather than the classical one-dimensional H-1 and C-13-NMR methods can provide clear evidence to verify the formation of the tri-block copolymers. In our measurements HMQC and HMBC NMR techniques directly detected the signal of ether bonds bridged in-between PBE dendrons and PEG blocks, therefore, the formation of the block copolymers are evidently confirmed in molecular level. This work also provides a general method to exactly confirm the formation of block copolymers.