In order to obtain a uniform and effectively toughened poly(lactic acid)film by blending with low content of poly(ethylene octene)(POE)with high elasticity,the tailored interfacial intermolecular interaction and entan...In order to obtain a uniform and effectively toughened poly(lactic acid)film by blending with low content of poly(ethylene octene)(POE)with high elasticity,the tailored interfacial intermolecular interaction and entanglement between the two phases of the PLA/POE blend was innovatively constructed via the facile reactive melt blending process through the reaction of the epoxy/anhydride groups grafted on the POE chains with the end groups of PLA chains(PLA/GPOE-MPOE).It was observed that POE domains were embedded tightly in PLA matrix with a fuzzy interface and abundant interface transition area,and the impact fractured surface of the blend showed an obvious plastic deformation with less occurrence of fibrillation of PLA matrix or interfacial de-bonding.Compared with neat PLA and directly blended PLA/POE blends,the PLA/GPOE-MPOE blend exhibited much higher complex viscosity/storage modulus,much lower tanδvalues in the terminal region,and obvious strain-hardening behavior.The deviation in viscoelastic behavior of PLA/GPOE-MPOE from linear PLA indicated the enhanced molecular entanglement between the long-branched chains,resulting in an enhancement of the stretching ability during biaxial drawing of the blend.Uniform PLA/GPOE-MPOE films with draw ratio as high as 7×7 were obtained through biaxial stretching,which showed much higher tensile strength and the elongation at break than that of neat PLA and PLA/POE film.This work provides a facile method for fabricating toughening PLA films with application potentials.展开更多
The surface ofpoly（ethylene terephthalate）（PET） films is inert, hydrophobic, and incompatible with blood, which has limited its practical bioapplication. In this case, better biocompatibility could be achieved by ...The surface ofpoly（ethylene terephthalate）（PET） films is inert, hydrophobic, and incompatible with blood, which has limited its practical bioapplication. In this case, better biocompatibility could be achieved by surface modification. In this study, the grafted copolymer of functional methoxypolyethylene glycol（mPEG） derivatives and styrene from the PET surfaces was prepared via surface-initiated atom transfer radical polymerization（SI-ATRP）. The structures, composition, properties and surface morphology of the grafted PET films were characterized by Fourier transform infrared spectroscopy（FTIR）, X-ray photoelectron spectroscopy（XPS）, contact angle measurements and scanning electronic microscopy（SEM）. The results indicate that the surface of the PET films has been covered by a thick targeted copolymer layer that converted the hydrophobic surface of PET to an amphiphilic surface. The bacte- rial adhesion and cell culture results indicate the copolymer-grafted PET film may possess good biocompatibility.展开更多
基金financially supported by the National Natural Science Foundation of China(No.51773122 and No.51933007)the International Scientific and Technological Cooperation Project of Sichuan Province(No.2020YFH0084)
文摘In order to obtain a uniform and effectively toughened poly(lactic acid)film by blending with low content of poly(ethylene octene)(POE)with high elasticity,the tailored interfacial intermolecular interaction and entanglement between the two phases of the PLA/POE blend was innovatively constructed via the facile reactive melt blending process through the reaction of the epoxy/anhydride groups grafted on the POE chains with the end groups of PLA chains(PLA/GPOE-MPOE).It was observed that POE domains were embedded tightly in PLA matrix with a fuzzy interface and abundant interface transition area,and the impact fractured surface of the blend showed an obvious plastic deformation with less occurrence of fibrillation of PLA matrix or interfacial de-bonding.Compared with neat PLA and directly blended PLA/POE blends,the PLA/GPOE-MPOE blend exhibited much higher complex viscosity/storage modulus,much lower tanδvalues in the terminal region,and obvious strain-hardening behavior.The deviation in viscoelastic behavior of PLA/GPOE-MPOE from linear PLA indicated the enhanced molecular entanglement between the long-branched chains,resulting in an enhancement of the stretching ability during biaxial drawing of the blend.Uniform PLA/GPOE-MPOE films with draw ratio as high as 7×7 were obtained through biaxial stretching,which showed much higher tensile strength and the elongation at break than that of neat PLA and PLA/POE film.This work provides a facile method for fabricating toughening PLA films with application potentials.
基金Supported by the National Natural Science Foundation of China（No.51203015）, the Natural Science Foundation of Jiangsu Province, China~o.BK2012786）, Qing Lan Project and the Changzhou Science and Technology Support Program, China （No.CE20150002）.
文摘The surface ofpoly（ethylene terephthalate）（PET） films is inert, hydrophobic, and incompatible with blood, which has limited its practical bioapplication. In this case, better biocompatibility could be achieved by surface modification. In this study, the grafted copolymer of functional methoxypolyethylene glycol（mPEG） derivatives and styrene from the PET surfaces was prepared via surface-initiated atom transfer radical polymerization（SI-ATRP）. The structures, composition, properties and surface morphology of the grafted PET films were characterized by Fourier transform infrared spectroscopy（FTIR）, X-ray photoelectron spectroscopy（XPS）, contact angle measurements and scanning electronic microscopy（SEM）. The results indicate that the surface of the PET films has been covered by a thick targeted copolymer layer that converted the hydrophobic surface of PET to an amphiphilic surface. The bacte- rial adhesion and cell culture results indicate the copolymer-grafted PET film may possess good biocompatibility.
