In this paper the miscibility of poly (ε-caprolactone) (PCL) and aliphatic polycarbonate (APC) is studied by using DSC. The results show that PCL and APC are miscible in all ranges of composition. The interaction par...In this paper the miscibility of poly (ε-caprolactone) (PCL) and aliphatic polycarbonate (APC) is studied by using DSC. The results show that PCL and APC are miscible in all ranges of composition. The interaction parameter between the polymers is calculated from the melting point depression data. Using optical microscope, the shapes of the PCL spherulites in the blends are observed.展开更多
A PES-PC (polyethersulfone-polycarbonate) multi block random copolymer was synthesized with two oligomers, polyethersulfone and polycarbonate. The effects of the copolymer, as a compatibilizer, on the morphology and...A PES-PC (polyethersulfone-polycarbonate) multi block random copolymer was synthesized with two oligomers, polyethersulfone and polycarbonate. The effects of the copolymer, as a compatibilizer, on the morphology and compatibility of the PES-PC blends were investigated. It was found that the addition of this copolymer to the PES-PC blends could improve their compatibility.展开更多
In this research, recycled-polyethylene terephthalate (PET) and polycarbonate (RPET/PC) blends fabricated by vented barrel injection molding were presented to better understand the effect of devolatilization during mo...In this research, recycled-polyethylene terephthalate (PET) and polycarbonate (RPET/PC) blends fabricated by vented barrel injection molding were presented to better understand the effect of devolatilization during molding process. The effect of dried pellets, non-dried pellets, using an opened-vented hole, and using a closed-vented hole on the miscibility, morphology, thermal properties and mechanical properties of RPET/PC blends was investigated. The results indicated that no drying decreases dispersion, thermal properties, and mechanical properties of RPET/PC blends due to hydrolysis degradation of recycled-PET during the injection molding process. Using the venting system with non-dried RPET/PC blends partially improves dispersion, thermal properties and molecular weight of RPET/PC blends processed without drying, giving results that are similar to those processed with drying. Regarding the flexural properties, using the venting system without drying prevents the flexural properties from decreasing in RPET/PC blends, if the amount of RPET is less than 75 wt%. When the content of RPET is over 75 wt%, using the venting system does not eliminate the decrease in flexural properties of RPET/PC blends. When the venting system is applied to non-dried RPET, despite hydrolysis degradation of RPET not being completely eliminated, the damaging effects are nonetheless reduced compared with those samples processed without the venting system. As a result, vented barrel injection molding hardly prevents non-dried RPET/PC blends from having reduced flexural properties when the content of RPET is greater than 75 wt%.展开更多
Polyamide (PA6) and polycarbonate (PC) were prepared by a Brabender mixer ( PLV- 151) at 240℃ with 30 rpm for duration of 8 and 6 minutes respectively. The epoxy resin (E) addition can lead to substantial mic...Polyamide (PA6) and polycarbonate (PC) were prepared by a Brabender mixer ( PLV- 151) at 240℃ with 30 rpm for duration of 8 and 6 minutes respectively. The epoxy resin (E) addition can lead to substantial microstructural changes in the PA6/PC blends. Scanning electron microscope (SEM) was used to observe the mixtures characterized by the domains of clearly segregated homophases and voids between the two polymers. PA6/PC of polyamide 6 and polycarbonate with epoxy resin addition under the composition ratio of 20/80, 20/80/1, 40/60/1 and 40/60, were tested to verify the key role of epoxy in promoting the compatibility of PA6 with PC during blending.展开更多
Low cycle fatigue crack propagation (FCP) behavior of two PC/ABSblends with a weight ra- tio of PC to ABS being 80/20 and 60/40,respectively, is investigated. Experiments are carried out by usingstandard compact tensi...Low cycle fatigue crack propagation (FCP) behavior of two PC/ABSblends with a weight ra- tio of PC to ABS being 80/20 and 60/40,respectively, is investigated. Experiments are carried out by usingstandard compact tension (CT) specimens. The fracture surfaces areexamined with a scanning electron mi- croscope (SEM). It is shownthat the FCP resistance of PC/ABS blend with 20/100 ABS particles ishigher than that of PC/ABS blend with 40/100 ABS particles. It isfound that proper ABS particle content can result in the tougheningof PC/ABS blends through particle cavitation and shear yielding inmatrix.展开更多
This paper experimentally studies the tensile deformation behavior of poly- carbonate (PC), acrylonitrile-butadiene-styrene (ABS), and PC/ABS blends (with the blending ratios of PC to ABS being 80:20, 60:40, 50...This paper experimentally studies the tensile deformation behavior of poly- carbonate (PC), acrylonitrile-butadiene-styrene (ABS), and PC/ABS blends (with the blending ratios of PC to ABS being 80:20, 60:40, 50:50, and 40:60) from low to high strain rates. Using the universal MTS-810 machine and the split Hopkinson tension bar (SHTB) testing system, the quasi-static and impact tension tests are carried out at the room temperature. The curves of the true stress and the true strain are obtained. The deformation behaviors of PC, ABS, and PC/ABS blends are characterized in detail. The linear relationship between the strain rate and the yielding stress is given.展开更多
In this study, four hydroxyl-terminated polydimethylsiloxanes (PDMSOH) with different viscosities and hydroxyl contents were used to improve the toughness of polycarbonate (PC) through reactive melt blending. A la...In this study, four hydroxyl-terminated polydimethylsiloxanes (PDMSOH) with different viscosities and hydroxyl contents were used to improve the toughness of polycarbonate (PC) through reactive melt blending. A largely improved toughness of PC has been achieved, and the low temperature toughness of PC/PDMSOH blends could overtake that of PC homopolymer in much higher temperatures (e.g. -10 ~C versus 23 ~C). Moreover, it was found that the more the hydroxyl content, the less the PDMSOH was needed to reach the highest toughness, suggesting that equivalent molar ratio between the carbonyl group content of PC and the hydroxyl group content of PDMSOH was required for the toughening of PC. Ultraviolet spectrophotometry was used to analyze the possible reaction between PC and PDMSOH. Contact angle was measured to assess the change of interfacial interaction between PC and PDMSOH as change of viscosity and hydroxyl content. The formation of PC-co-PDMSOH copolymer was believed to be the key for the toughening effect. This work gives a profound recommendation of the optimum kind and dosage of PDMSOH which should be used to improve the toughness of PC and will find immediate industrial applications.展开更多
The influences of hyperbranched polyethylenimine (hPEI), which possesses many reactive amino end-groups, on the blending properties of bisphenol-A polycarbonate (PC) and amorphous polyamide (aPA) were systematic...The influences of hyperbranched polyethylenimine (hPEI), which possesses many reactive amino end-groups, on the blending properties of bisphenol-A polycarbonate (PC) and amorphous polyamide (aPA) were systematically investigated. Scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) were used to observe the effect of hPE1 on morphologies of PC and aPA phases in bulk blends. While the interfacial fracture toughness between planar PC and aPA layers with and without hPEI was studied by using augmented double cantilever beam (ADCB) method. Results show that the compatibility in PC/aPA blends can be significantly improved by adding a small amount of hPEI, mainly due to the interchange reactions between the polymers leading to the formation of block copolymers, cross-linked polymers and molecules with other constitutions. The augmented double cantilever beam experiments showed that the reactive process drastically reinforced the interfacial adhesion between planar layers of PC and aPA. However, degradation takes place during annealing at 180℃, which was responsible for the production of small molar mass species of PC.展开更多
基金The subject supported by National Natural Science Foundation of China
文摘In this paper the miscibility of poly (ε-caprolactone) (PCL) and aliphatic polycarbonate (APC) is studied by using DSC. The results show that PCL and APC are miscible in all ranges of composition. The interaction parameter between the polymers is calculated from the melting point depression data. Using optical microscope, the shapes of the PCL spherulites in the blends are observed.
基金Supported by the National Natural Science Foundation of China(No.50203004).
文摘A PES-PC (polyethersulfone-polycarbonate) multi block random copolymer was synthesized with two oligomers, polyethersulfone and polycarbonate. The effects of the copolymer, as a compatibilizer, on the morphology and compatibility of the PES-PC blends were investigated. It was found that the addition of this copolymer to the PES-PC blends could improve their compatibility.
文摘In this research, recycled-polyethylene terephthalate (PET) and polycarbonate (RPET/PC) blends fabricated by vented barrel injection molding were presented to better understand the effect of devolatilization during molding process. The effect of dried pellets, non-dried pellets, using an opened-vented hole, and using a closed-vented hole on the miscibility, morphology, thermal properties and mechanical properties of RPET/PC blends was investigated. The results indicated that no drying decreases dispersion, thermal properties, and mechanical properties of RPET/PC blends due to hydrolysis degradation of recycled-PET during the injection molding process. Using the venting system with non-dried RPET/PC blends partially improves dispersion, thermal properties and molecular weight of RPET/PC blends processed without drying, giving results that are similar to those processed with drying. Regarding the flexural properties, using the venting system without drying prevents the flexural properties from decreasing in RPET/PC blends, if the amount of RPET is less than 75 wt%. When the content of RPET is over 75 wt%, using the venting system does not eliminate the decrease in flexural properties of RPET/PC blends. When the venting system is applied to non-dried RPET, despite hydrolysis degradation of RPET not being completely eliminated, the damaging effects are nonetheless reduced compared with those samples processed without the venting system. As a result, vented barrel injection molding hardly prevents non-dried RPET/PC blends from having reduced flexural properties when the content of RPET is greater than 75 wt%.
文摘Polyamide (PA6) and polycarbonate (PC) were prepared by a Brabender mixer ( PLV- 151) at 240℃ with 30 rpm for duration of 8 and 6 minutes respectively. The epoxy resin (E) addition can lead to substantial microstructural changes in the PA6/PC blends. Scanning electron microscope (SEM) was used to observe the mixtures characterized by the domains of clearly segregated homophases and voids between the two polymers. PA6/PC of polyamide 6 and polycarbonate with epoxy resin addition under the composition ratio of 20/80, 20/80/1, 40/60/1 and 40/60, were tested to verify the key role of epoxy in promoting the compatibility of PA6 with PC during blending.
基金the Excellent Young Teachers Programthe Research Foundation for Doctoral Project of the Ministry of Education of China.
文摘Low cycle fatigue crack propagation (FCP) behavior of two PC/ABSblends with a weight ra- tio of PC to ABS being 80/20 and 60/40,respectively, is investigated. Experiments are carried out by usingstandard compact tension (CT) specimens. The fracture surfaces areexamined with a scanning electron mi- croscope (SEM). It is shownthat the FCP resistance of PC/ABS blend with 20/100 ABS particles ishigher than that of PC/ABS blend with 40/100 ABS particles. It isfound that proper ABS particle content can result in the tougheningof PC/ABS blends through particle cavitation and shear yielding inmatrix.
基金supported by the National Natural Science Foundation of China (No. 11142004)the Shang-hai Leading Academic Discipline Project (No. S30106)the Innovative Foundation of Shanghai University
文摘This paper experimentally studies the tensile deformation behavior of poly- carbonate (PC), acrylonitrile-butadiene-styrene (ABS), and PC/ABS blends (with the blending ratios of PC to ABS being 80:20, 60:40, 50:50, and 40:60) from low to high strain rates. Using the universal MTS-810 machine and the split Hopkinson tension bar (SHTB) testing system, the quasi-static and impact tension tests are carried out at the room temperature. The curves of the true stress and the true strain are obtained. The deformation behaviors of PC, ABS, and PC/ABS blends are characterized in detail. The linear relationship between the strain rate and the yielding stress is given.
基金financially supported by the National Natural Science Foundation of China(Nos.21034005 and 51121001)
文摘In this study, four hydroxyl-terminated polydimethylsiloxanes (PDMSOH) with different viscosities and hydroxyl contents were used to improve the toughness of polycarbonate (PC) through reactive melt blending. A largely improved toughness of PC has been achieved, and the low temperature toughness of PC/PDMSOH blends could overtake that of PC homopolymer in much higher temperatures (e.g. -10 ~C versus 23 ~C). Moreover, it was found that the more the hydroxyl content, the less the PDMSOH was needed to reach the highest toughness, suggesting that equivalent molar ratio between the carbonyl group content of PC and the hydroxyl group content of PDMSOH was required for the toughening of PC. Ultraviolet spectrophotometry was used to analyze the possible reaction between PC and PDMSOH. Contact angle was measured to assess the change of interfacial interaction between PC and PDMSOH as change of viscosity and hydroxyl content. The formation of PC-co-PDMSOH copolymer was believed to be the key for the toughening effect. This work gives a profound recommendation of the optimum kind and dosage of PDMSOH which should be used to improve the toughness of PC and will find immediate industrial applications.
基金financially supported by the National Natural Science Foundation of China(No.21004069)
文摘The influences of hyperbranched polyethylenimine (hPEI), which possesses many reactive amino end-groups, on the blending properties of bisphenol-A polycarbonate (PC) and amorphous polyamide (aPA) were systematically investigated. Scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) were used to observe the effect of hPE1 on morphologies of PC and aPA phases in bulk blends. While the interfacial fracture toughness between planar PC and aPA layers with and without hPEI was studied by using augmented double cantilever beam (ADCB) method. Results show that the compatibility in PC/aPA blends can be significantly improved by adding a small amount of hPEI, mainly due to the interchange reactions between the polymers leading to the formation of block copolymers, cross-linked polymers and molecules with other constitutions. The augmented double cantilever beam experiments showed that the reactive process drastically reinforced the interfacial adhesion between planar layers of PC and aPA. However, degradation takes place during annealing at 180℃, which was responsible for the production of small molar mass species of PC.