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PC/ABS Blend (ab + blend)
Selected AbstractsEffects of microcompounding process parameters on the properties of ABS/polyamide-6 blends based nanocompositesJOURNAL OF APPLIED POLYMER SCIENCE, Issue 5 2008Güralp Özkoç Abstract Melt intercalation method was applied to produce acrylonitrile-butadiene-styrene/polyamide-6 (ABS/PA6) blends based organoclay nanocomposites using a conical twin-screw microcompounder. The blend was compatibilized using a maleated olefinic copolymer. The effects of microcompounding conditions such as screw speed, screw rotation-mode (co- or counter-), and material parameters such as blend composition and clay loading level on the morphology of the blends, dispersibility of nanoparticles, and mechanical properties were investigated. Furthermore, corotating screws were modified to achieve elongational flow which is efficient for obtaining dispersive mixing. The morphology was examined by SEM analysis after preferential extraction of the minor phase. Subsequently, the SEM micrographs were quantitatively analyzed using image analyzer software. The morphology of the blends indicated that processing with counter-rotation at a given screw speed yielded coarser morphology than that of processed with corotation. X-ray diffraction analysis showed that highest level of exfoliation is observed with increasing PA6 content, at 200 rpm of screw speed and in corotation mode. Also, the effects of screw speed, screw rotation mode, and screw modification were discussed in terms of XRD responses of the nanocomposites. The aspect ratio of the clay particles which were measured by performing image analysis on TEM micrographs exhibited a variation with processing conditions and they are in accordance with the modulus of the nanocomposites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] In-line analysis of the influence of monomeric and oligomeric hindered amine on the hydrolysis of polycarbonate in a PC/ABS blendJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2010Vipin V. Rajan Abstract The polycarbonate/polyacrylonitrile butadiene styrene (PC/ABS) blends lose mechanical properties when exposed to outdoor conditions. This is due to the ultraviolet (UV) induced photo-oxidation of the PC phase and the polybutadiene portion of the ABS. It is known that ABS can be stabilised against terrestrial light by the use of hindered amine in combination with a UV absorber. However, such hindered amine cannot be used when PC is present in a multi component polymer blend. The hydrolysis of PC is accelerated when a small amount of hindered amine light stabilisers (HALS) is incorporated in the resin and is exposed to elevated temperature. In this article the effect of monomeric and oligomeric hindered amine on the hydrolysis of PC during the compounding of PC/ABS blend in a twin screw extruder at 240°C is observed by means of in-line UV-vis spectroscopy. Tinuvin 765 was used as monomeric hindered amine and Tinuvin 622 as oligomeric hindered amine. The molecular weight of the compounded sample was determined by gel permeation chromatography (GPC) and the rheological properties were observed using an online viscometer. It was found that the extent of hydrolysis induced by the oligomeric hindered amine is less compared to monomeric amine. It was also observed that polymeric hindered amine imparts better dispersion of the ABS phase into the polymer blend. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Observations of physical aging in a polycarbonate and acrylonitrile,butadiene,styrene blendJOURNAL OF APPLIED POLYMER SCIENCE, Issue 1 2008Jacky K. Y. Tang Abstract The effects of physical aging of a 75 : 25 PC/ABS blend have been studied using differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR). From DSC, two distinct peak endotherms at about 90°C and 110°C, which are associated with the glass transition of ABS (Tg,ABS) and PC (Tg,PC) components, respectively, were observed. When progressive aging was monitored at 80°C for over 1000 h, the changes in enthalpic relaxation, glass and fictive temperatures for the blend followed similar trends to those already seen in the literature for PC aged between 125 and 130°C. The rate of enthalpy relaxation was also comparable. The plot of peak endotherm against logarithmic aging time for the PC blend constituent, however, behaved quite differently from the linear relationship known for highly aged PC. The ABS peak component also appeared to be insensitive to aging. Both observations were confirmed to be statistically significant using analysis of variance methods. Using temperature modulated-DSC, there is evidence that aging increases the blend miscibility as the Tg,PC shifts toward the stationary Tg,ABS during aging. Parallel FTIR investigations found oxidation of butadiene during aging to be even at this relatively low temperature, forming hydroxyl and carbonyl degradation products. The presence of ABS in the blend also appeared to have prevented the shifting from the trans-cis to trans-trans arrangement of the carbonate linkage, which is a well-known phenomenon during elevated temperature aging of PC alone. Moreover, the carbonate linkage appears to have been at the lower energy, trans-trans, arrangement prior to the aging process. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Weld line characteristics of PC/ABS blend.JOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008Abstract The effects of reactive compatibilizer and processing temperature on the morphology and the mechanical properties at the weld line of 60/40 (wt/wt) poly- carbonate (PC) and acrylonitrile-butadiene-styrene (ABS) copolymer blends were investigated. Amine functionalized styrene/n -phenyl maleimide/maleic anhydride terpolymer (amine-SPMIMA) was used as the in-situ reactive compatibilizer for PC/ABS blend. Weld tensile strength increased as the content of amine-SPMIMA was increased. Weld impact strength showed maximum value for the blend containing about 3% amine-SPMIMA. The variation in the mechanical property at the weld line was correlated with the change in the morphology of the blend. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Cone calorimeter analysis of UL-94 V-rated plastics,FIRE AND MATERIALS, Issue 4 2007Alexander B. Morgan Abstract Cone calorimeter analysis was conducted on 18 thermoplastics with different UL-94 vertical burn test (V) ratings. Ratings varied from V-0 to no rating (NR), and the types of thermoplastics included were polycarbonate (PC), acrylonitrile,butadiene,styrene (ABS), PC/ABS blends, high-impact polystyrene (HIPS), polypropylene (PP), and poly(vinyl chloride) (PVC). Our analysis of the cone calorimeter data found that there were correlations between UL-94 V rating and some cone calorimeter measurements (peak heat release rate (HRR) average and HRR at 60 s) and no relationship for other measurements (time to ignition and total heat release). However, no precise correlation was found due to significant differences in flame retardant mechanism and polymer fuel energy values. In this paper, we seek to explain further why a broad quantitative relationship between UL-94 V and cone calorimeter remains elusive, and also to show how the cone calorimeter can be used to understand why a material passes or fails a particular UL-94 V rating. Copyright © 2006 John Wiley & Sons, Ltd. [source] Morphological, mechanical, and rheological studies of PVC/ABS blends in the presence of maleic anhydrideJOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 2 2010Pegah Mohammad Hosseinpour A novel method of enhancing compatibility in PVC/ABS blends is the use of ABS-grafted-(maleic anhydride) (ABS- g -MAH) as a compatibilizer. In this study, maleic anhydride was grafted onto ABS (initiated by peroxide) in an internal mixer. Grafting degree was determined by a back-titration method, and certain amounts of the resultant ABS- g -MAH were added to PVC/ABS blends during their melt blending in the mixer. The weight ratio of PVC to ABS was kept at 70:30. Evaluation of compatibilization was accomplished via tensile and notched Izod impact tests, scanning electron microscopy (SEM), and rheological studies. According to the SEM micrographs, better dispersion of the rubber phase and its finer size in properly compatibilized blends were indications of better compatibility. Besides, in the presence of a proper amount [5 parts per hundred parts of PVC (php)] of ABS- g -MAH, PVC/ABS blends showed significantly higher impact strengths than uncompatibilized blends. This result, in turn, would be an indication of better compatibility. In the presence of 5 php of compatibilizer, the higher complex viscosity and storage modulus, as well as a lower loss modulus and loss factor in the range of frequency studied, indicated stronger interfacial adhesion as a result of interaction between maleic anhydride and the PVC-SAN matrix. J. VINYL ADDIT. TECHNOL., 2010. © 2010 Society of Plastics Engineers [source] | ||||||||||