Polymer Blends Of Polycarbonate Research Articles

Cover Image, Volume 139, Issue 42

The cover image by Takayuki Hirai, Yoshimi Muraoka, and Hirotaka Okamoto shows transparent composites achieved by refractive index matching between glass fiber textiles and polymer blends of polycarbonate (PC) and polycaprolactone (PCL). The PC/PCL blend shows good transparency due to its miscibility, and refractive index matching between glass fiber and PC/PCL blend can be achieved by optimizing a composition ratio of PC and PCL. The transparent composite was obtained by impregnating the refractive index adjusted PC/PCL into a woven glass fiber. The composite shows optical transparency and excellent mechanical properties. DOI: 10.1002/app.52925

Study of Miscibility in Polymer Blends Obtained from Binary Inclusion Complexes of γ-Cyclodextrin and Polycarbonate/Poly(Ethylene Terephthalate)

In this work the synthesis and characterization of the nanostructure of polymer blends of polycarbonate (PC) and poly(ethylene terephthalate) (PET) obtained from their inclusion complexes with γ-cyclodextrin are reported. The blends prepared by this method present differences in their miscibility compared with those blends obtained by conventional methods like solution casting, coprecipitation, or melt blending. In order to understand the influence of molecular weight in the inclusion complex process, PCs of Mw = 64,000 and 28,000 g/mol were used. The analysis of the nanostructured blend by Fourier transform infrared (FTIR), 1H-nuclear magnetic resonance (1H-NMR), wide-angle X-ray diffraction (WAXD), differential scanning colorimetry (DSC), and thermogravimetric analysis (TGA) suggests the existence of specific intermolecular interactions between PC and PET that promote miscibility in this normally immiscible polymer blend. Studies by FTIR confirm that the miscibility found was not due to a transesterification reaction during DSC analysis. There were also differences in the morphology of the blends, observed by optical microscopy, obtaining a more homogeneous phase for blends formed in inclusion complexes. The results obtained strongly suggest an improvement in miscibility of the PC/PET blends.

Transport through track etched polymeric blend membrane

Polymer blends of polycarbonate (PC) and polysulphone (PSF) having thickness, 27 μm, are prepared by solution cast method. The transport properties of pores in a blend membrane are examined. The pores were produced in this membrane by a track etching technique. For this purpose, a thin polymer membrane was penetrated by a single heavy ion of Ni7+ of 100 MeV, followed by preferential chemical etching of the ion track. Ion permeation measurements show that pores in polymeric membrane are charged or neutralized, which depends upon the variation in concentration of the solvent. TheV-Icurve at concentration, N/10, shows that the pores are negatively charged, whereas at concentration, N/20, the linear nature ofV-I curve indicates that the pores approach towards neutralized state and on further concentration, N/40, the pores become fully neutralized, consequently the rectifier behaviour of pores has been omitted.The gas permeability of hydrogen and carbon dioxide of this membrane was measured with increasing etching time. The permeability was measured from both the sides. Permeability at the front was larger than the permeability at the back which shows asymmetric behaviour of membranes.

Study of gas permeation for asymmetric track-etched polymer blends

Polymer blends of polycarbonate (PC) and polysulphone (PSF) having thickness 27 μ m are prepared in different concentration (1:0), (1:1) and (1:3) by solution cast method. It was found that, as the concentration of PSF in blends increases, the permeability of hydrogen and carbon dioxide decreases. The membranes were irradiated by Ni 7 + ion of 100 MeV. Gas permeability of hydrogen and carbon dioxide was measured for the irradiated samples, permeability for the both gases increases with increases etching time. Permeability from ion incidence side is higher than the permeability from ion emergence side. This difference in permeability from both the sides is attributed to the conical shape of the track generated by ions, which shows asymmetrical behaviour of tracks created in membranes. Permselectivity of hydrogen over carbon dioxide also increases with increasing PSF concentration from both the sides and it found maximum for 1:3 (PC:PSF) track-etched membrane.

Effect of heat treatment on dynamic viscoelastic properties of immiscible polycarbonate-linear low density polyethylene blends

Dynamic viscoelastic properties of immiscible polymer blends of polycarbonate (PC) and linear low density polyethylene (LLDPE) were investigated by use of a non-resonant forced-vibration method. The blends in the form of extruded sheets were the same as that used in the first phase of the Versailles Project on Advanced Materials and Standards (VAMAS), the Technical Working Party on Polymer Blends (TWP-PB). Structures and properties of polymer blends containing a semi-crystalline phase are affected by their thermal history and the domain morphology. Matrix and dispersed phases are aligned to the extrusion direction of the blend sheet. The results of dynamic mechanical properties for blends and pure parent polymers confirm the immiscibility of PC with LLDPE. The effect of heat treatment on the dynamic viscoelastic properties of blend sheets were studied. Also, the discussion was conducted for the comparison of experimental results and dynamic storage modulus (E') calculated by use of mechanical models.

Effect of Rubber Content in Acrylonitrile–Butadiene–Styrene and Additional Rubber on The Polymer Blends of Polycarbonate and Acrylonitrile–Butadiene–Styrene

Higher ABS rubber content in the polycarbonate (PC)/acrynitrile–butadiene–styrene (ABS) blend resulted in toughness improvement in terms of tensile, Izod impact and strain energy release rate at a cost of higher melt viscosity. The extra-added core-shell rubber particles with poly(methyl methacrylate) (PMMA) or acrylonitrile–styrene (SAN) outer shell resided mainly in the ABS phase and further improved the resulted blends toughness. The addition of styrene–maleic anhydride (SMA) copolymer in the PC/ABS blends caused severe coagulation of the rubber particles in the ABS phase and left a greater fraction of the SAN phase without presence of rubber. The toughness improvement by increasing rubber content must be compensated by the increase of melt viscosity and this fact has to be taken into consideration in selecting the starting materials of the PC/ABS blends.

Miscibility study of polycarbonate and SBS triblock copolymer blends

Polymer blends of Polycarbonate (PC) and Styrene-Butadiene-Styrene triblock (SBS) have been investigated. SBS copolymers have four different styrenic contents, three of which are linear SBS. PC and PS blends are partially miscible as revealed by dynamic mechanical analysis with two clear Tgs near 100–150°C. On the contrary, PC/SBS blends have only one Tg with a left shoulder. Based on the PS domain model of pure SBS, we suggest a micelle model based on the structure when the micelle and absorb PC in the PC/SBS blends. The micelle plays an important role in improving the miscibility. The proposed micelle model has been empolyed to interpret the testing results, such as toughness, impact strength, dynamic mechanical property and SEM morphologies. This proposed micelle model seems a worth-while method to explain the properties of partialtly miscible blends of PC and SBS.

Effect of polycarbonate molecular weight on polymer blends of polycarbonate and ABS

AbstractThe melt viscosity of polycarbonate/acrylonitrile‐butadiene‐styrene (PC/ABS) blends relative to PC is significantly lower, even lower than that of pure ABS in some compositions. Annealing above the Tg of PC coalesces and coarsens phase structure in core and skin regions. Increase in the molecular weight of PC in PC/ABS blends results in low‐temperature fracture toughness improvement but suffers from the disadvantage of higher melt viscosity. The selection of PC in PC/ABS blends must be a compromise between the toughness advantages of higher PC molecular weight and the disadvantage of higher melt viscosity. © 1993 John Wiley & Sons, Inc.