Determination of the diffusion of poly(ethylene glycol)in polypropylene using ATR-FTIR

The diffusion of poly(ethy1ene glycol)(PEG)in polypropylene(PP)was investigated using attenuated total reflectance Fourier Transform Infrared Spectroscopy(ATR-FTIR),Atomic Force Micrograph(AFM),and Scanning Electron Microscopy(SEM).It has been found that the diffusion of PEG in PP was greatly affected by the annealing temperature and the molecular weight of PEG.Higher temperature was in favor of PEG to diffuse in PP with fast velocity and reached diffusion equilibrium with shorter time.PEG with higher molecular weight was distributed in PP with bigger phase domains and had lower diffusivity,which resulted in its lesser enrichment on the surface of the PP blend film.

Synthesis and characterization of macromolecular surface modifier PP-g-PEG for polypropylene

A novel macromolecular surface modifier,polypropylene-grafted-poly(ethylene glycol)copolymer(PP-g-PEG),was synthesized by coupling polypropylene containing maleic anhydride with monohydroxyl-termi-nated poly(ethylene glycol).The effects of the reaction condition on the graft reactions were studied.The copo-lymers were characterized by IR,1 H NMR,thermogravi-metry(TG)and differential scanning calorimetry(DSC).The results indicated that the graft reactions were hin-dered by increasing the molecular weight of PP or PEG.The graft copolymer was found to have a higher initial thermal degradation temperature and lower crystalliza-tion capacity as compared with pure PP,and the side chain of PEG hindered the PP chain from forming a per-fect b crystal.The thermal stability of PP-g-PEG decreased with the increasing content or molecular weight of PEG.The copolymers were blended with polypropy-lene to modify the surface hydrophilicity of the products.The results of attenuated total reflectance FTIR spectro-scopy(ATR-FTIR)showed that PP-g-PEG could diffuse preferably onto the surface of the blends and be suitableas an effectual macromolecular surface modifier for PP.