Polypropylene(PP)/ethylene-octene copolymer(POE) blends were prepared with a twin-screw extruder.Their dynamic mechanical behavior were systematically investigated.The results show that PP/POE blends are heterogen...Polypropylene(PP)/ethylene-octene copolymer(POE) blends were prepared with a twin-screw extruder.Their dynamic mechanical behavior were systematically investigated.The results show that PP/POE blends are heterogeneities with a partial compatible two-phase structure,the glass transition temperature of PP phases in the blends tends to shift towards high temperature with increasing the POE content,and the glass transition temperature of POE phases shifts towards the low temperature with increasing the PP content.The Kerner's dispersed phase model and co-continuous phase model can reasonably predict the visco-elasticity of PP/POE blends with different compositions.Additionally,the morphological structure of the blends can be estimated via comparing the predicted DMA behavior with the experimental data.展开更多
In this work, polypropylene (PP)/polystyrene (PS) blends with different organoclay concentrations were prepared via melt compounding. Differing from the results of previous reports, the organoclay platelets are mostly...In this work, polypropylene (PP)/polystyrene (PS) blends with different organoclay concentrations were prepared via melt compounding. Differing from the results of previous reports, the organoclay platelets are mostly located in the dispersed PS phase instead of the interface. The dimensions of the dispersed PS droplets are greatly reduced and apparent compatibilization effect still exists, which cannot be explained by the traditional compatibilization mechanism. A novel compatibilization mecha- nism, "cutting" to apparently compatibilize the immiscible PP/PS blends was proposed. The organoclay platelets tend to form a special "knife-like structure" in the PS domain under the shear stress of the continuous PP phase during compounding. The "clay knife" can split the dispersed PS domain apart and lead to the dramatic reduction of the dispersed domain size.展开更多
A new Nylon 11(PA11)/polyethylene-octene(POE) blends compatibilized by maleic anhydride grafted mixture polyethyleneocten(POE-g-MAH) was prepared through melt blending method.The isothermal crystallization kinet...A new Nylon 11(PA11)/polyethylene-octene(POE) blends compatibilized by maleic anhydride grafted mixture polyethyleneocten(POE-g-MAH) was prepared through melt blending method.The isothermal crystallization kinetics and melting behaviors of PA11/POE blends were investigated in detail by differential scanning calorimetry(DSC) and polarized optical microscope.The n values of PA11 blending with POE or POE-g-MAH are almost similar with pure PA11,which indicates that the effect of POE and POE-g-MAH on nucleation and growth of PA11 crystal is slight.The overall crystallization rate of PA11/POE blends are higher than ones of pure PA11 at the same crystallization temperatures,but they decrease significantly when POE-g-MAH is added into PA11/POE blends.DSC heating curves of both PA11 and its blends exhibit two melting peaks,but the two melting peak become weaker when POE-g-MAH is add into PA11/POE blend systems.And the spherulite size is reduced significantly by the addition of POE-g-MAH compared with pure PA11 and PA11/POE blends.展开更多
PA6/PTFE blends with varying polytetrafluoroethylene content from 3% to 15%(mass fraction) were irradiated by 60Co gamma-ray with various doses(20,50 and 100 kGy) under ambient conditions.Moisture absorption test,U-no...PA6/PTFE blends with varying polytetrafluoroethylene content from 3% to 15%(mass fraction) were irradiated by 60Co gamma-ray with various doses(20,50 and 100 kGy) under ambient conditions.Moisture absorption test,U-notched Charpy impact test and quasi-static tension and bending were conducted to investigate the effect of irradiation on moisture absorption and mechanical properties of the blends.It is shown that the exposure of the blend to 60Co irradiation improves the tensile modulus,tensile strength and flexural modulus due to irradiation induced cross-linking in PA6 phase.However,the Charpy impact strength of the blends is much lower than that of the original PA6 and it decreases slightly with the increase of irradiation dose.Moreover,the flexural modulus increases to a maximum value and then decreases with further increasing the PTFE content,and the moisture absorption decreases with the increase of the PTFE content and irradiation dose.展开更多
Poly(phenylene oxide)/renewable polyamide 11 (PPO/PA11 20/80) blends toughened with glycidylmethacrylate grafted ethylene-n-octene copolymer (GEOC) were prepared in a co-rotating twin-screwextruder. The reaction betwe...Poly(phenylene oxide)/renewable polyamide 11 (PPO/PA11 20/80) blends toughened with glycidylmethacrylate grafted ethylene-n-octene copolymer (GEOC) were prepared in a co-rotating twin-screwextruder. The reaction between GEOC and PPO/PA11 blend was analyzed by gel content tests. Themorphology of PPO/PA11/GEOC blends was observed by scanning electron microscope. The SEMresults showed that PPO formed the continuous phase, though it is a minority component of blends. Withincreasing GEOC content from 5 to 15 wt% the morphology of the blends transformed from droplet-matrix toco-continuous structure, in which both PA11 and PPO phases are continuous. The blend with co-continuousmorphology had better mechanical properties than those with droplet-matrix morphology. The impactstrength of the PPO/PA11/GEOC blends was much higher compared to the one without GEOC as well asPA11 due to the compatibilizing effect, which was also proved by DSC analysis, rheological behavior (MFR,DMTA) and tensile properties.展开更多
In this study, the adsorptive properties of L-menthol, moisture vapor transmission rate, and mechanical properties of poly (ethylene terephthalate) (PET), polypropylene (PP), and their blends were evaluated in contain...In this study, the adsorptive properties of L-menthol, moisture vapor transmission rate, and mechanical properties of poly (ethylene terephthalate) (PET), polypropylene (PP), and their blends were evaluated in containers fabricated by injection molding without a compatibilizing agent. These containers intended to hold pharmaceutical solutions containing lipophilic chemicals such as L-menthol. By the addition of a small amount of PP, the moisture barrier properties of PET were effectively improved, but its anti-adsorptive property was reduced. The strength of the PET/PP blends was reduced, but some PET/PP blends were still able to bear the experimental load required for application in eye-drop containers. PET/PP = 9/1 and PET/PP = 8/2 were found to be most applicable for using in the fabrication of containers for medicinal solutions.展开更多
基金Supported by the National Natural Science Foundation of China(No.20490220)Open Fund of State Key Laboratory of Plastic Forming Simulation and Die & Mould Technology,China(No.05-10)+1 种基金Open Fund of Hubei Key Laboratory of Materials Chemistry and Service FailureProgram for New Century Excellent Talents in Universities of China(No.NCET-05-0640)
文摘Polypropylene(PP)/ethylene-octene copolymer(POE) blends were prepared with a twin-screw extruder.Their dynamic mechanical behavior were systematically investigated.The results show that PP/POE blends are heterogeneities with a partial compatible two-phase structure,the glass transition temperature of PP phases in the blends tends to shift towards high temperature with increasing the POE content,and the glass transition temperature of POE phases shifts towards the low temperature with increasing the PP content.The Kerner's dispersed phase model and co-continuous phase model can reasonably predict the visco-elasticity of PP/POE blends with different compositions.Additionally,the morphological structure of the blends can be estimated via comparing the predicted DMA behavior with the experimental data.
文摘In this work, polypropylene (PP)/polystyrene (PS) blends with different organoclay concentrations were prepared via melt compounding. Differing from the results of previous reports, the organoclay platelets are mostly located in the dispersed PS phase instead of the interface. The dimensions of the dispersed PS droplets are greatly reduced and apparent compatibilization effect still exists, which cannot be explained by the traditional compatibilization mechanism. A novel compatibilization mecha- nism, "cutting" to apparently compatibilize the immiscible PP/PS blends was proposed. The organoclay platelets tend to form a special "knife-like structure" in the PS domain under the shear stress of the continuous PP phase during compounding. The "clay knife" can split the dispersed PS domain apart and lead to the dramatic reduction of the dispersed domain size.
文摘A new Nylon 11(PA11)/polyethylene-octene(POE) blends compatibilized by maleic anhydride grafted mixture polyethyleneocten(POE-g-MAH) was prepared through melt blending method.The isothermal crystallization kinetics and melting behaviors of PA11/POE blends were investigated in detail by differential scanning calorimetry(DSC) and polarized optical microscope.The n values of PA11 blending with POE or POE-g-MAH are almost similar with pure PA11,which indicates that the effect of POE and POE-g-MAH on nucleation and growth of PA11 crystal is slight.The overall crystallization rate of PA11/POE blends are higher than ones of pure PA11 at the same crystallization temperatures,but they decrease significantly when POE-g-MAH is added into PA11/POE blends.DSC heating curves of both PA11 and its blends exhibit two melting peaks,but the two melting peak become weaker when POE-g-MAH is add into PA11/POE blend systems.And the spherulite size is reduced significantly by the addition of POE-g-MAH compared with pure PA11 and PA11/POE blends.
基金Project(10772156) supported by the National Natural Science Foundation of ChinaProject supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry of China
文摘PA6/PTFE blends with varying polytetrafluoroethylene content from 3% to 15%(mass fraction) were irradiated by 60Co gamma-ray with various doses(20,50 and 100 kGy) under ambient conditions.Moisture absorption test,U-notched Charpy impact test and quasi-static tension and bending were conducted to investigate the effect of irradiation on moisture absorption and mechanical properties of the blends.It is shown that the exposure of the blend to 60Co irradiation improves the tensile modulus,tensile strength and flexural modulus due to irradiation induced cross-linking in PA6 phase.However,the Charpy impact strength of the blends is much lower than that of the original PA6 and it decreases slightly with the increase of irradiation dose.Moreover,the flexural modulus increases to a maximum value and then decreases with further increasing the PTFE content,and the moisture absorption decreases with the increase of the PTFE content and irradiation dose.
文摘Poly(phenylene oxide)/renewable polyamide 11 (PPO/PA11 20/80) blends toughened with glycidylmethacrylate grafted ethylene-n-octene copolymer (GEOC) were prepared in a co-rotating twin-screwextruder. The reaction between GEOC and PPO/PA11 blend was analyzed by gel content tests. Themorphology of PPO/PA11/GEOC blends was observed by scanning electron microscope. The SEMresults showed that PPO formed the continuous phase, though it is a minority component of blends. Withincreasing GEOC content from 5 to 15 wt% the morphology of the blends transformed from droplet-matrix toco-continuous structure, in which both PA11 and PPO phases are continuous. The blend with co-continuousmorphology had better mechanical properties than those with droplet-matrix morphology. The impactstrength of the PPO/PA11/GEOC blends was much higher compared to the one without GEOC as well asPA11 due to the compatibilizing effect, which was also proved by DSC analysis, rheological behavior (MFR,DMTA) and tensile properties.
文摘In this study, the adsorptive properties of L-menthol, moisture vapor transmission rate, and mechanical properties of poly (ethylene terephthalate) (PET), polypropylene (PP), and their blends were evaluated in containers fabricated by injection molding without a compatibilizing agent. These containers intended to hold pharmaceutical solutions containing lipophilic chemicals such as L-menthol. By the addition of a small amount of PP, the moisture barrier properties of PET were effectively improved, but its anti-adsorptive property was reduced. The strength of the PET/PP blends was reduced, but some PET/PP blends were still able to bear the experimental load required for application in eye-drop containers. PET/PP = 9/1 and PET/PP = 8/2 were found to be most applicable for using in the fabrication of containers for medicinal solutions.