Compatibility enhancement of ABS/PVC blends

The compatibilizing effect of poly(styrene-co-acrylonitrile) (SAN) whose acrylonitrile (AN) content is 25 wt % (SAN 25) in poly(acrylonitrile-co-butadiene-co-styrene) (ABS)/poly(vinyl chloride) (PVC) blend was studied when the AN content of the matrix SAN in ABS was 35 wt % (SAN 35). When some amount of matrix SAN 35 was replaced by SAN 25 in a ABS/PVC (50/50 by weight) blend, the mixed phase of SAN and PVC at the interface was thickened, and about a twofold increase of impact strength was observed. The changes in morphology, dynamic mechanical properties, and rheological properties by the compatibilizing effect of SAN 25 were observed. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 70: 705–709, 1998     

Preparation of graded materials for miscible polycarbonate/poly(methyl methacrylate) blends by segregation under shear flow

Exposure to shear flow produced by a pressure-driven capillary rheometer provides a concentration gradient without phase separation in miscible polymer blends of bisphenol-A polycarbonate containing low-molecular-weight poly(methyl methacrylate) (PMMA). The strand surface extruded from the rheometer contains a large amount of PMMA. However, the strand is transparent because there is no light scattering due to phase separation. The segregation behavior, that is, enrichment of the PMMA content at the strand surface, is enhanced when the molecular weight of PMMA is low. Furthermore, the segregation is also enhanced at high temperatures and at high shear rates. By contrast, the die length barely affects the degree of segregation. The segregation phenomenon should be noted because it may facilitate the modification of the surface properties of various products.     

Mechanical properties of blends of polycarbonate with unmodified and maleic anhydride grafted ABS

Blends of polycarbonate/acrylonitrile–butadiene–styrene terpolymer (PC/ABS) and polycarbonate/maleic anhydride grafted ABS (PC/MABS) were prepared over the whole range of compositions using a single-screw extruder. Tensile, flexural, notched Izod impact properties, and the heat deflection temperature of these blends were determined. Mechanical properties of PC/MABS blends are nearly equal to or higher than, those predicted by the rule of mixtures, whilst those of PC/ABS blends show nearly equal, or negative deviation, from the rule of mixtures. The notched impact strength of PC/MABS blends shows a positive blending effect and proportionate increase from 25wt% PC to 75wt% PC. Scanning electron micrographs were taken of etched surfaces of selective blends. © 1998 SCI.     

不同组成ABS对ABS／PMMA合金性能的影响

选用两种不同牌号的ABS树脂与PMMA共混，对其组成与性能的关系进行了详细的研究。试验结果表明，不同组成的ABS对ABS/PMMA混合物的光学性能、力学性能以及流变行为的影响都有显著的不同．     

Mechanical performance of ternary in situ polycarbonate/poly(acrylonitrile‐butadiene‐styrene)/liquid crystalline polymer composites

Ternary in situ polycarbonate (PC)/poly(acrylonitrile‐butadiene‐styrene) (ABS)/liquid crystalline polymer(LCP) composites were prepared by injection molding. The LCP used was a versatile Vectra A950, and the matrix of composite specimens was PC/ABS 60/40 by weight. Maleic anhydride (MA) copolymer and solid epoxy resin (bisphenol type‐A) were used as compatibilizers for these composites. The tensile, dynamic mechanical, impact, morphology, and thermal properties of the composites were studied. Tensile tests showed that the tensile strength of the PC/ABS/LCP composite in the longitudinal direction increased markedly with increasing LCP content. However, it decreased slowly with increasing LCP content in the transverse direction. The modulus of this composite in the longitudinal direction appeared to increase considerably with increasing LCP content, whereas the incorporation of LCP into PC/ABS blends had little effect on the modulus in the transverse direction. The impact tests revealed that the Izod impact strength of the composites in both longitudinal and transverse direction decreased with increasing LCP content up to 15 wt %; thereafter it increased slowly with increasing LCP. Dynamic mechanical analyses (DMA) and thermogravimetric measurements showed that the heat resistance and heat stability of the composites tended to increase with increasing LCP content. Scanning electron microscopy observation and DMA measurement indicated that the additions of epoxy and MA copolymer to PC/ABS matrix appeared to enhance the compatibility between the PC and ABS, and between the matrix and LCP. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 2274–2282, 1999     

Recycling of ABS and ABS/PC blends

The aim of this work within the framework of mechanical recycling of polymers is upgrading recycled engineering plastics by means of a blending technique. Four different plastics from dismantled Volvo cars have been investigated. They are poly(acrylonitrile‐butadiene‐styrene) (ABS) and ABS‐polycarbonate (ABS/PC) as major components and poly(methyl methacrylate) (PMMA) and polyamide (PA) as minor components. Blending recycled ABS and PC/ABS (70/30) with a small amount of methyl methacrylate‐butadiene‐styrene core‐shell impact modifiers gives the mixture better impact properties than any of its individual components. Some 10% of PMMA from tail light housings can follow the PC/ABS blends made. The property profile will rather be improved. However, PA is an incompatible component that should be sorted out from the mixture. Antioxidants and metal deactivators do not help the recyclates show better mechanical properties. Two toughness measurements, Charpy impact strength and J‐integral method, show complimentary results for such blends. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 510–515, 1999     

Physical ageing of polycarbonate and PMMA by dynamic mechanical measurements

The physical ageing properties of polycarbonate and poly(methyl methacrylate) have been measured by dynamic mechanical experiments at different temperatures. It appears that the horizontal shift proposed by Struik to superpose the experimental curves for different ageing times is only a first approximation. The McCrum analysis has been used in the α region but cannot be applied between the α and β relaxations.     

Isotactic polypropylene/polymethylmethacrylate blends: Effects of addition of propylene-graft-methylmethacrylate copolymer

A novel graft copolymer of unsaturated propylene with methyl methacrylate (uPP-g-PMMA) was added to binary blends of isotactic polypropylene (iPP) and atactic poly(methyl methacrylate) (aPMMA) with a view to using such a copolymer as a compatibilizer for iPP/aPMMA materials. Optical microscopy (OM), scanning electron microscopy, wide angle X-ray scattering (WAXS), and small angle X-ray scattering (SAXS) techniques showed that, contrary to expectation, the uPP-g-PMMA addition does not provide iPP/aPMMA compatibilized materials, irrespective of composition. As a matter of fact the degree of dispersion of the minor component achieved following the addition of uPP-g-PMMA copolymer remained quite comparable to that exhibited by binary blends of iPP and aPMMA with no relevant evidence of adhesion or interconnection between the phases. On the other hand the crystalline texture was deeply modified by the copolymer presence. With increasing uPP-g-PMMA content (w/w) the iPP spherulites were found to become more open and coarse and the dimensions and number per unit area of the amorphous interspherulitic contact regions were found to increase. According to such OM results the copolymer uncrystallizable sequences were assumed to be mainly located in interfibrillar and interspherulitic amorphous contact regions. SAXS analysis demonstrated that the phase structure developed in the iPP/aPMMA/uPP-g-PMMA blends is characterized by values of the long period increasing linearly with increasing copolymer content (w/w). Assuming a two phase model for the iPP spherulite fibrillae, constituted of alternating parallel crystalline lamellae and amorphous layers, the lamellar structure of the iPP phase in the ternary blends is characterized by crystalline lamellar thickness (L_c) and an interlamellar amorphous layer (L_a) higher than that shown by plain iPP and L_c and L_a values both increased with increasing uPP-g-PMMA content (w/w). Such SAXS results have been accounted for by assuming that a cocrystallization phenomenon between propylenic sequences of the uPP-g-PMMA copolymer and iPP occurs. The development of the iPP lamellar structure in the iPP/aPMMA/uPP-g-PMMA blends was thus modeled hypothesizing that during such a cocrystallization process copolymer PMMA chains with comparatively lower molecular mass remain entrapped into the iPP interlamellar amorphous layer forming their own domains. Moreover, evidence of strong correlations between the crystallization process of the uPP-g-PMMA copolymer and the iPP crystallization process was shown also by differential scanning calorimetry and WAXS experiments. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 2377–2393, 1997     

Morphological and mechanical properties of PP/ABS blends compatibilized with PP‐g‐acrylic acid

Polypropylene (PP) and acrylonitrile–butadiene–styrene (ABS) blends were prepared by a melt extrusion process. PP‐g‐acrylic acid was used as a compatibilizer. Blends with various compositions of PP, compatibilizer, and ABS were prepared and studied for morphological and mechanical properties. PP‐rich ternary blends showed good morphological and mechanical properties. The use of 5 wt % PP‐g‐acrylic acid as a compatibilizer resulted in a fine and homogeneous dispersion of the ABS phase in the PP phase. The experimental data of the tensile modulus showed good agreement in PP‐rich compositions with that generated from Kerner's model with perfect adhesion. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1731–1741, 2001     

Compatibilizing effects for semicrystalline polymer-infiltrated amorphous polymer matrix: Mechanical (toughness), thermal,and morphological behavior of compatibilized polypropylene/polycarbonate blends

Polycarbonates (PCs) have been extensively blended with polyolefins such as polypropylene (PP) due to pecuniary advantages. Although the toughness of a pristine PC matrix has been examined, limited works have investigated the toughness of heterogeneous PC/PP blend systems, focusing merely on PC-dispersed PP matrices. In this study, the mechanical/thermal properties of PP-dispersed PC matrix (PC-rich phase) were examined by using potential compatibilizers: poly(maleic anhydride-alt-α-olefin) (OM), ethylene-co-acrylic acid (EA), and cyclic olefin copolymer. The incorporation of 0.5–5.0 phr of compatibilizers (OM and EA) into PC substantially enhanced the toughness of PC/PP15 blends according to four different testing methods. The highest toughness was obtained with 0.5 phr of OM and EA. The compatibilized blends displayed enhanced various thermal properties such as glass transition temperatures, heat deflection temperature, and degradation point, due to the compatibilizing effect. Moreover, 0.5 phr of compatibilizers (OM and EA) were determined as the most effective concentration in terms of toughness and most properties, without compromising strengths and moduli. The morphology of PP-dispersed PC matrix (crystalline polymer-infiltrated amorphous polymer matrix) differed from that of PC-dispersed PP matrix. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47684.     

Isothermal relaxation of specific volume and density fluctuation in poly(methyl methacrylate) and polycarbonate

Small-angle X-ray scattering (SAXS) was utilized to measure the density fluctuation, in two samples of poly(methyl methacrylate) and a sample of polycarbonate, as a function of temperature on a constant rate cooling and heating; and also as a function of time on isothermal annealing. For the purpose of comparison, measurements were also made on the specific volume of poly(methyl methacrylate) under comparable conditions. In the transition region of 20°–40° interval around T_g both the specific volume and the density fluctuation decreased with time on isothermal annealing. At temperatures below the transition region, however, the density fluctuation showed no observable change, while the specific volume continued to decrease linearly with the logarithm of time. In order to interpret the density fluctuation in terms of the concept of free volume, a simple model is presented in which holes of various sizes are randomly distributed in the continuous medium, and an equation is then derived to correlate the observed density fluctuation to the free volume fraction and the weight-average size of the holes.     

Compatibility studies of sulfonated poly(ether ether ketone)–poly(ether imide)–polycarbonate ternary blends

Binary blends of the sulfonated poly(ether ether ketone) (SPEEK)–poly(ether imide) (PEI) and SPEEK–polycarbonate (PC), and ternary blends of the SPEEK–PEI–PC, were investigated by differential scanning calorimetry. SPEEK was obtained by sulfonation of poly(ether ether ketone) using 95% sulfuric acid. From the thermal analysis of the SPEEK–PEI blends, single glass transition temperature (T_g) was observed at all the blend composition. For the SPEEK–PC blends, double T_gs were observed. From the results of thermal analysis, it is suggested that the SPEEK–PEI blends are miscible and the SPEEK–PC blends are immiscible. Polymer–polymer interaction parameter (χ₁₂) of the SPEEK–PEI blends was calculated from the modified Lu and Weiss equation, and found to range from −0.011 to −0.825 with the blend composition. For the SPEEK–PC blends, the χ₁₂ values were calculated from the modified Flory–Huggins equation, and found to range from 0.191 to 0.272 with the blend composition. For the SPEEK–PEI–PC ternary blends, phase separation regions that showed two T_gs were found to be consistent with the spinodal curves calculated from the χ₁₂ values of the three binary blends. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 2488–2494, 2000     

A study on weld line morphology and mechanical strength of injection molded polystyrene/poly(methyl methacrylate) blends

In this work, the mechanical strength and weld line morphology of injection molded polystyrene/poly(methyl methacrylate) (PS/PMMA) blends were investigated by scanning electron microscopy (SEM) and mechanical property test. The experimental results show that the tensile strength of PS/PMMA blends get greatly decreased due to the presence of the weld line. Although the tensile strength without the weld line of PS/PMMA (70/30) is much higher than that of the PS/PMMA (30/70) blend, their tensile strength with weld line shows reversed change. The viscosity ratio of dispersed phase over matrix is a very important parameter for control of weld‐line morphology of the immiscible polymer blend. In PS/PMMA (70/30) blend, the PMMA dispersed domains at the core of the weld line are spherically shaped, which is the same as bulk. While in the PS/PMMA (30/70) blend, the viscosity of the dispersed PS phase is lower than that of the PMMA matrix, the PS phase is absent at the weld line, and PS particles are highly oriented parallel to the weld line, which is a stress concentrator. This is why weld line strength of PS/PMMA (30/70) is lower than that of PS/PMMA (70/30) blend. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1856–1865, 2002; DOI 10.1002/app.10450     

Mechanical properties of blends of nylon with chemically modified ABS

Tensile, flexural and impact properties were measured of a heterogeneous polymer blend system, consisting of nylon 6 and a chemically modified ABS (MABS). It was found from the tensile tests that nylon-richer blends show yielding behaviour and nylon-leaner blends show necking behaviour. The addition of MABS increases the modulus, whereas the tensile strength and percentage elongation at break decrease and go through a minimum. The impact strength is increased to a maximum of approximately three times when 20 wt% of MABS is added to nylon 6. In order to interpolate the mechanical properties observed, empirical equations are given which are found to describe the experimental data rather well. Photomicrographs were taken of the tensile fractured surfaces using a scanning electron microscope.     

PVC/MBS共混物的形态及力学性能

采用种子乳液聚合方法,在聚丁二烯乳胶粒子上接枝甲基丙烯酸甲酯（MMA）和苯乙烯（St）,制得MBS核壳接枝共聚物,并将其作为增韧剂与聚氯乙烯（PVC）共混制备PVC/MBS共混物。考察了接枝不同MMA和St含量的MBS在PVC中的分散状态及其对PVC/MBS共混物力学性能。结果表明,当MBS壳层中MMA含量增加时,MBS粒子在PVC基体中的分散状态被改善;PVC/MBS共混物的冲击强度随之增加,冲击强度最高时为1117.74 J/m;当MBS中接枝少量St时,PVC/MBS共混物呈现韧性断裂,冲击值最高时为1039.33 J/m;当MBS接枝大量St时,会产生内包容现象,不利于提高PVC共混物的冲击强度。     

ABS／PVC共混改性的研究

考察了PVC含量对ABS/PVC共混体系性能的影响。为了进一步提高共混体系的性能，在体系中分别加入CPE、MBS做为第三组分。通过性能比较，发现MBS可有效提高共混体系的综合性能。为了增加共混体系的阻燃性能，加入助阻燃剂Sb2O3，结果表明共混体系的阻燃性能有了很大提高。     

PE-C、ABS改性硬质聚氯乙烯的性能和增韧机理

研究不同用量的氯化聚乙烯（PE-C）和（丙烯腈/丁二烯/苯乙烯）共聚物（ABS）对硬聚氯乙烯（PVC-U）二元共混体系力学性能的影响。用电子显微镜观察了冲击断面和微观结构,结果发现,随增韧剂用量不同两种共混体系的冲击性能曲线均可分为“脆性断裂”,“脆韧转变”和“韧性断裂”三个区。不同的是,PE-C在PVC-U中形成网络结构,而ABS是以颗粒或聚集体分散在PVC连续相中,拉伸时,PE-C易与基体共同发生剪切屈服产生“剪切带”,ABS作为应力集中体引发银纹。“剪切带”和“茛纹”都对PVC-U增韧起着重要的作用。     

Mica as a filler for ABS/polycarbonate blends

Mica was incorporated in ABS/PC:65/35 blends prepared on a Haake Torque Rheometer System 9000 with Rheomix 600 mixer. To improve the polymer/filler interaction, a treatment using silane on mica surface was performed. Studies were conducted concerning mechanical properties (flexural and impact strength), thermal properties (DSC and Vicat softening temperature), rheology, and flame retardancy. The composition with 30 phr of mica gives the best properties and efficiency in reducing the rate of burning, then becoming an alternative material to be explored and possibly meet the new requirements sought by these market blends. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 1361–1365, 1999     

Polycarbonate and co-continuous polycarbonate/ABS blends: influence of specimen thickness

The influence of specimen thickness on the fracture behaviour of polycarbonate (PC) and co-continuous PC/ABS (50/50) blends was studied in single edge notch tensile tests at 1 m/s and different temperatures (−80 to 130 °C). Specimen thickness ranged from 0.1 to 8 mm. In the co-continuous PC/ABS blends the rubber concentration in the ABS was 0, 15 and 30 wt%. The change in fracture toughness was typified by the change in brittle-to-ductile transition temperature (T_bd).T_bd of pure PC depended strongly on specimen thickness, leading to very low transition temperatures for thin PC specimens. PC/ABS 0%, a 50/50 blend of PC and SAN (i.e. ABS without polybutadiene (PB)), was a brittle blend and showed a very high T_bd close to the T_g of SAN. T_bd did not seem to be influenced by specimen thickness. PC/ABS blends with 15 and 30% PB in ABS showed improved T_bd compared to PC/SAN and PC, indicating effective rubber toughening. T_bd decreased with decreasing thickness for PC/ABS specimens thicker than 1.5 mm. However, T_bd increased with decreasing thickness for specimens below 1.5 mm thickness. In thin specimens, the rubber-filled blend is less effective rubber toughening. The plane strain stress condition needed for rubber cavitation is apparently not present in thin specimens.     

ABS回收料/PBT合金的增容改性

以丙烯腈–丁二烯–苯乙烯塑料回收料(rABS)为基体,将其与聚对苯二甲酸丁二酯(PBT)共混,制备了rABS/PBT合金,并以自制的甲基丙烯酸缩水甘油酯(GMA)接枝rABS(rABS-g-GMA)为相容剂,研究了PBT及rABS-gGMA对rABS/PBT合金力学性能和相态结构的影响。结果表明,PBT的加入提高了rABS的强度,但降低了韧性;随着rABS-g-GMA用量的增加,合金的拉伸和弯曲强度没有明显变化,但断裂伸长率和缺口冲击强度明显提升,当rABS/PBT质量比为70/30,rABS-g-GMA用量为15份时,合金的断裂伸长率和缺口冲击强度分别较未加相容剂的提高了147%和51.6%。rABS-g-GMA的加入提高了合金的损耗与储能模量以及损耗因子峰值,阻碍了合金中PBT的结晶,生成了更多的无定形区,促使PBT分散粒子尺寸减小,分布均匀,明显改善了rABS和PBT间的相容性。