Flow properties of ABS (acrylonitrile–butadiene–styrene) terpolymer

ABS (acrylonitrile–butadiene–styrene) terpolymer is a two-phase thermoplastic with SAN (styrene–acrylonitrile) copolymer constituting the continuous phase (matrix). The flow properties of ABS with varying molecular parameters were studied using a capillary viscometer at the shear rate range encountered in its processing. The viscosity-average molecular weights (M_v) of matrix SAN with 26% acrylonitrile content are in the range of 90,000 to 150,000, and M_v of poly-butadiene-are in the range of 150,000 to 170,000. The weight-average molecular weight of the matrix SAN is the main controlling factor for the flow properties of ABS at low shear rate, while the molecular weight distribution of the matrix SAN becomes increasingly important with the increase of shear rate. The presence of SAN grafted polybutadiene increases the melt viscosity of ABS by 40–60% over comparable free SAN copolymer and also decreases the activation energy at constant shear stress to 24–25 kcal/mole from the 33–36 kcal/mole for free SAN. The die swell of ABS and SAN can be correlated with the dynamic shear modulus G′, and the melt fracture of ABS and SAN starts at G′ equal to 3.6 × 10⁶ dynes/cm².     

Phase separation of some clear polyblends

By using variations of elution and precipitation techniques, a clear ABS resin is found to be a mixture of a styrene–butadiene rubbery copolymer, a methyl methacrylate–styrene–acrylonitrile copolymer, and a graft of the methyl methacrylate–styrene–acrylonitrile copolymer onto the styrene–butadiene rubber. A clear impact acrylic is separated into a methyl methacrylate–styrene–acrylonitrile copolymer and a methyl methacrylate–butadiene rubbery copolymer. Photomicrographs indicate that clarity in the clear ABS and impact acrylic is achieved by matching refractive indices of the continuous and dispersed polymer phases.     

Mechanical properties and morphology of LCP/ABS blends compatibilized with a styrene–maleic anhydride copolymer

A co‐polyester liquid crystalline polymer (LCP) was melt blended with an acrylonitrile–butadiene–styrene copolymer (ABS). LCP fibrils are formed and a distinct skin/core morphology is observed in the injection moulded samples. At higher LCP concentration (50 wt%), phase inversion occurs, where the dispersed LCP phase becomes a co‐continuous phase. While the tensile strength and Young's modulus remain unchanged with increasing LCP content up to 30 wt% LCP, a significant enhancement of the modulus at 50 wt% LCP is observed due to the formation of co‐continuous morphology. The blend modulus is lower than the values predicted by the rule of mixtures, suggesting a poor interface between the LCP droplets and ABS matrix. A copolymer of styrene and maleic anhydride (SMA) was added in the LCP/ABS blends during melt blending. It is observed that SMA has a compatibilizing effect on the blend system and an optimum SMA content exists for mechanical properties enhancement. SMA improves the interfacial adhesion, whereas excess of SMA reduces the LCP fibrillation. Copyright © 2003 Society of Chemical Industry     

Augmenting the performance of acrylonitrile–butadiene–styrene plastics for low‐noise dynamic applications

The main objective of this study was to enhance the performance of acrylonitrile–butadiene–styrene (ABS) plastics for dynamic structural applications, including those of automobile relevance. First, ABS was modified by blending with maleic anhydride grafted styrene–ethylene–butadiene–styrene block copolymer (MA‐g‐SEBS) in various proportions. Squeaking noise characteristics were evaluated by measurement of the frictional behavior in an in‐house fabricated friction testing apparatus, and the results are explained on the basis of the change in surface energy upon modification. Detailed dynamic mechanical analyses (strain, frequency, and temperature sweep) revealed significant improvements in the damping characteristics of the modified ABS, especially that modified with 10 wt % MA‐g‐SEBS, without much sacrifice in its mechanical strength. The modulus values predicted with Kerner's model of the blends were well correlated with the morphological changes upon modification. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Study of the influence of adding styrene–ethylene/butadiene–styrene in acrylonitrile–butadiene–styrene and polyethylene blends

This work studies the recovery of two grades of acrylonitrile–butadiene–styrene (ABS) contaminated with low‐density polyethylene (LDPE), by adding styrene–ethylene/butadiene–styrene (SEBS). To simulate contaminated ABS, virgin ABS was mixed with 1, 2, 4, and 8% of LDPE and then extruded at 220°C. After this, the ABS with the highest percentage of LDPE (8%) was mixed with 1, 2, 4, and 8% of SEBS and then extruded. Different blends were mechanically, rheologically, optically, and dimensionally characterized to study how different percentages of LDPE and SEBS modify their properties. The results obtained show how the tensile strength, Young modulus, elongation, and impact strength linearly decrease as the LDPE amount increases, for both natural and black ABS. Through the addition of SEBS to contaminated ABS, it is possible to improve its impact strength and elongation values nearly to those of virgin ABS. However, its tensile strength and Young modulus show no improvement, and even show a slight reduction. Regarding the rheological properties, the LDPE contamination in ABS causes a remarkable decrease in viscosity, and adding SEBS to the blend lowers its viscosity even further for both natural and black grades. This reduction is not a negative aspect, but rather quite the reverse, as the more fluid the material, the easier the mold injection process becomes. POLYM. ENG. SCI., 54:1313–1324, 2014. © 2013 Society of Plastics Engineers     

Influence of rubber content in ABS in wide range on the mechanical properties and morphology of PC/ABS blends with different composition

A series of acrylonitrile–butadiene–styrene (ABS) with different rubber content were prepared by diluting ABS grafting copolymer containing 60% rubber with a styrene–acrylonitrile copolymer. ABS prepared were blended with bisphenol‐A‐polycarbonate (PC) at the ratio of 70/30, 50/50, and 30/70 to prepare PC/ABS blends. Influence of rubber content in ABS on the properties of ABS and PC/ABS blends were investigated. PC/ABS blends with different compositions got good toughness when the rubber in ABS increased to the level that ABS itself got good toughness. The tensile properties and processability of PC/ABS blends decreased with the increase of the total rubber content introduced into the blends. ABS with the rubber content of 30 wt% is most suitable to be used to prepare PC/ABS blends. The rubber content in ABS affected the viscosity of ABS, and subsequently the viscosity ratio of PC to ABS. As a result, the morphology of PC/ABS blends varied. The increase of rubber content in ABS results in finer structure of PC/ABS blends. POLYM. ENG. SCI. 46:1476–1484, 2006. © 2006 Society of Plastics Engineers.     

Blends of acrylonitrile–butadiene–styrene/waste poly(ethylene terephthalate) compatibilized by styrene maleic anhydride

Waste poly(ethylene terephthalate) (PET) from thin bottles was blended with acrylonitrile–butadiene–styrene (ABS) copolymer in different proportions, up to 10 wt %. Styrene maleic anhydride (SMA) copolymer was used as a compatibilizer. The tensile strength and heat deflection temperature of the blend were higher than that of virgin ABS. Flexural modulus remained unaffected, although a slight decrease in impact property was observed. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2593–2599, 2001     

Environmental degradation of some polymer blends. Blends of polystyrene with acrylonitrile butadiene styrene,poly(vinyl chloride), and polybutadiene and blends of polybutadiene with poly(vinyl chloride)

One class of polymer/additive which has become increasingly important is polymer blends. In this study the ultimate tensile strength, elongation at break, and the modulus of acrylonitrile–butadiene–styrene, poly(vinyl chloride), polybutadiene and polystyrene and their blends have been studied over an entire binary composition range. We have correlated these mechanical properties to their degradation behavior under natural and accelerated weathering by measurement of various indices during thermal and natural weathering. It was found that during natural weathering the presence of polystyrene in acrylonitrile–butadiene–styrene (ABS) improved the weatherability of ABS; the converse was true when the blends were heated in an air oven at 100°C. It was also found that the weatherability of PB was improved in the presence of polystyrene and large improvement in the rigidity was observed. Similarly, from a measurement of carbonyl index, it was found that PVC has a stabilizing effect on PB. In many cases, the 50:50 composition of the polymers gave the best compromise of good mechanical properties, heat stability, and outdoor weathering. The mechanisms of possible interactions between the degrading polymers are discussed.     

Modification of acrylonitrile–butadiene–styrene terpolymer by grafting with maleic anhydride in the melt. I. Preparation and characterization

The graft copolymerization of maleic anhydride (MAH) onto acrylonitrile–butadiene–styrene terpolymer (ABS) was carried out with dicumyl peroxide (DCP) and benzoyl peroxide (BPO) as the binary initiators and with styrene as the comonomer in the molten state. IR spectra confirmed that MAH was successfully grafted onto the ABS backbone. A reaction mechanism was proposed: the grafting most likely took place through the addition of MAH radicals to the double bond of the butadiene region of ABS. Influences such as the MAH concentration, the initiators and their concentrations, the reaction temperature, the rotating speed, and the comonomer concentration were studied. The results indicated that using styrene as a comonomer and DCP/BPO as binary initiators was beneficial for the graft copolymerization. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1249–1254, 2003     

Effects of styrene–acrylonitrile contents on the properties of ABS/SAN blends for fused deposition modeling

This paper was to assess the effects of styrene–acrylonitrile (SAN) contents on the glass transition temperature (T_g), melt flow index (MFI), and mechanical properties of acrylonitrile–butadiene–styrene (ABS)/SAN blends for fused deposition modeling (FDM) process. The addition of SAN had little effects on T_g but could decrease the MFI and elongation at break while improving the tensile strength and modulus of ABS/SAN blends. For both longitudinal direction and transverse direction FDM printed specimens, the incorporation of SAN improved mechanical properties without sacrificing dimensional stability. This result was mainly attributed to the increasing content of continuous phase (SAN phase) and improvement in adhesion quality. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44477.     

The importance of char-forming reactions in thermoplastic polymers

The flammability and smoke generated from burning blends of acrylonitrile–butadiene–styrene (ABS) and polyvinylchloride (PVC) are discussed. Flammability was measured using standard oxygen index techniques and smoke production determined by the NBS method. The incorporation of some specific iron containing inorganic compounds into a range of blends of ABS and PVC considerably changes the burning characteristics of the polymer blend. Thermal stability at elevated temperatures and carbonaceous char formation are also discussed. The chemical role of iron compounds in reducing both the flammability and smoke production in ABS/PVC is considered.     

Effects of the polybutadiene/poly(styrene‐co‐acrylonitrile) ratio in a polybutadiene‐g‐poly(styrene‐co‐acrylonitrile) impact modifier on the morphology and mechanical behavior of acrylonitrile–butadiene–styrene blends

Polybutadiene‐g‐poly(styrene‐co‐acrylonitrile) (PB‐g‐SAN) impact modifiers with different polybutadiene (PB)/poly(styrene‐co‐acrylonitrile) (SAN) ratios ranging from 20.5/79.5 to 82.7/17.3 were synthesized by seeded emulsion polymerization. Acrylonitrile–butadiene–styrene (ABS) blends with a constant rubber concentration of 15 wt % were prepared by the blending of these PB‐g‐SAN copolymers and SAN resin. The influence of the PB/SAN ratio in the PB‐g‐SAN impact modifier on the mechanical behavior and phase morphology of ABS blends was investigated. The mechanical tests showed that the impact strength and yield strength of the ABS blends had their maximum values as the PB/SAN ratio in the PB‐g‐SAN copolymer increased. A dynamic mechanical analysis of the ABS blends showed that the glass‐transition temperature of the rubbery phase shifted to a lower temperature, the maximum loss peak height of the rubbery phase increased and then decreased, and the storage modulus of the ABS blends increased with an increase in the PB/SAN ratio in the PB‐g‐SAN impact modifier. The morphological results of the ABS blends showed that the dispersion of rubber particle in the matrix and its internal structure were influenced by the PB/SAN ratio in the PB‐g‐SAN impact modifiers. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2165–2171, 2005     

Mechanical,thermal and morphological properties of environmentally degradable ABS and poly(vinyl alcohol) blends

Blends of acrylonitrile–butadiene–styrene (ABS) with 5, 10, 15, and 20 wt % of poly(vinyl alcohol) (PV) were prepared by extruding in a corotating twin screw extruder. The ABS material was blended with PVA with the objective to enhance the degradability of ABS. The extrudate strands were cut into pellets and injection molded to make test specimens. These ABS/PVA blend specimens were tested for physicomechanical properties like tensile strength, elongation, modulus of elasticity, abrasion resistance, density, and water absorption, These blends were further characterized by melt flow Index, differential scanning calorimetry, thermogravimetry analysis, and scanning electron microscopy. The morphological analysis reveals the existence of PVA domains in the ABS matrix. Differential scanning calorimetry thermograms indicates the chemical interaction between ABS and PVA domains. The prepared blends show enhanced environmental and thermal degradation. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Influence of ABS type on morphology and mechanical properties of PC/ABS blends

The morphology and the mechanical properties of polycarbonate (PC) blends with different acrylonitrile–butadiene–styrene (ABS) materials were investigated. PC/ABS blends based on a mass-made ABS with 16% rubber and large (0.5–1μm) rubber particles are compared to blends based on an emulsion-made ABS with 50% rubber and small, monodisperse (0.12 μm) rubber particles over the full range of blend compositions. The blends with the bulk ABS showed excellent impact strength for most compositions, and those containing 50 and 70% PC exhibited ductile to brittle transition temperatures below that of PC. The blends with the emulsion ABS showed excellent toughness in sharp notch Izod impact tests at room temperature and in standard notch Izod impact tests at low temperatures near the T_g of the rubber. By melt blending the various ABS materials with a styrene–acrylonitrile (SAN 25) copolymer, materials with lower rubber concentrations were obtained. These materials were used in blends with PC to make comparisons at constant rubber concentration of 5, 10, and 15%. The results of this investigation show that brittle ABS materials can produce tough PC–ABS blends. It is apparent that small rubber particles toughen PC–ABS blends at lower rubber concentrations and at lower temperatures than is possible with large rubber particles. However, additional work is needed to understand the nature of toughening in these PC–ABS blends with different rubber phase morphologies. It is of particular interest to understand the exceptional ductility of some of the blends at low temperatures. © 1994 John Wiley & Sons, Inc.     

Crystallization behavior of PBT/ABS polymer blends

Poly(butylene terephthalate) (PBT) crystallization behavior is modified by blending it with acrylonitrile‐butadiene‐styrene copolymers (ABS). The effects of ABS on melting and crystallization of PBT/ABS blends have been examined. Most ABS copolymers of different rubber content and styrene/acrylonitrile ratios studied showed little effect on the melting behavior of PBT crystalline phase. However, ABS copolymer with high acrylonitrile content had a significant effect on the crystallization behavior of the PBT/ABS blends. The nucleation rate of the PBT crystalline phase decreased due to the presence of the high acrylonitrile content ABS, whereas the spherulitic growth rate increased significantly. These phenomena are attributed to changes in nucleation and growth mechanisms of PBT crystalline phase promoted by ABS. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 423–430, 1999     

Interfacial mechanical behavior of 3D printed ABS

We describe an experimental approach for characterizing the local mechanical behavior of acrylonitrile butadiene styrene (ABS) structures processed through fused deposition modeling. ABS test specimens processed in various build orientations were subject to multiscale mechanical tests as well as local morphology and chemical analyses. Instrumented indentation, local dynamic mechanical analysis, and atomic force microscopy tests were used to explore the mechanical behavior and morphology of build surfaces and weld interfaces. An interfacial stiffening effect was found for the majority of the specimens tested, with up to a 40% increase in the indentation elastic modulus measured with respect to the build surfaces. Raman spectroscopy mapping of the interfacial areas revealed ～30% less butadiene/styrene and butadiene/acrylonitrile ratios with respect to analysis of the build surfaces. The results provide insight into the multiscale behavior of additive manufactured structures and offer the potential to guide processing–structure–property understanding of these materials. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43671.     

Effects of mixing protocol on the performance of nanocomposites based on polyamide 6/acrylonitrile–butadiene–styrene blends

Toughening of polyamide 6 (PA6) can be achieved by appropriate addition of an elastomeric matrix phase; however, this leads to a loss of rigidity and mechanical strength. As a result, much research has been directed at obtaining an optimal balance between toughness and rigidity for these thermoplastics. The approach explored here is the formation of nanocomposites from PA6/acrylonitrile–butadiene–styrene (ABS) blends prepared by melt mixing with a modified montmorillonite (Cloisite® 30B) and styrene/maleic anhydride copolymer as a compatibilizer. The effect of the mixing sequence of the components on the morphology and properties is a primary focus. The morphology and mechanical properties of the materials were characterized by X‐ray diffraction, electron microscopy, and tensile and impact testing. Incorporation of the compatibilizer in the PA6/ABS blend increased toughness but decreased rigidity. A significant increase of modulus was observed for the nanocomposite blend compared with the blend or the matrix. This increase was attributed to the exfoliation of organoclay layers in the PA6 matrix phase. It was also observed that the morphology of the ABS dispersed phase was considerably influenced by the mixture sequence. POLYM. ENG. SCI., 52:1909–1919, 2012. © 2012 Society of Plastics Engineers     

Short glass fiber reinforced ABS and ABS/PA6 composites: Processing and characterization

In this study acrylonitrile‐butadiene‐styrene (ABS) terpolymer was reinforced with 3‐aminopropyltrimethoxysilane (APS)‐treated short glass fibers (SGFs). The effects of SGF concentration and extrusion process conditions, such as the screw speed and barrel temperature profile, on the mechanical properties of the composites were examined. Increasing the SGF concentration in the ABS matrix from 10 wt% to 30 wt% resulted in improved tensile strength, tensile modulus and flexural modulus, but drastically lowered the strain‐at‐break and the impact strength. The average fiber length decreased when the concentration of glass fibers increased. The increase in screw speed decreased the average fiber length, and therefore the tensile strength, tensile modulus, flexural modulus, and impact strength were affected negatively and the strain‐at‐break was affected positively. The increase in extrusion temperature decreased the fiber length degradation, and therefore the tensile strength, tensile modulus, flexural modulus, and impact strength increased. At higher temperatures the ABS matrix degraded and the mechanical strength of the composites decreased. To obtain a strong interaction at the interface, polyamide‐6 (PA6) at varying concentrations was introduced into the ABS/30 wt% SGF composite. The incorporation and increasing amount of PA6 in the composites broadened the fiber length distribution (FLD) owing to the low melt viscosity of PA6. Tensile strength, tensile modulus, flexural modulus, and impact strength values increased with an increase in the PA6 content of the ABS/PA6/SGF systems due to the improved adhesion at the interface, which was confirmed by the ratio of tensile strength to flexural strength as an adhesion parameter. These results were also supported by scanning electron micrographs of the ABS/PA6/SGF composites, which exhibited an improved adhesion between the SGFs and the ABS/PA6 matrix. POLYM. COMPOS. 26:745–755, 2005. © 2005 Society of Plastics Engineers     

Synthesis and characterization of ABS resin using in situ transferring from emulsion to suspension polymerization

A novel approach based on an emulsion in situ suspension polymerization process for synthesizing poly(acrylonitrile–butadiene–styrene) (ABS) resin is reported. Experimental results show that the reaction system can be transformed from an emulsion state to a suspension polymerization state steadily with the content of polybutadiene (PB) in the range 0–15 wt% in ABS resin. When PB is replaced by poly(styrene‐co‐butadiene) with the content of rubber particles being kept below 20 wt%, the emulsion system can be easily transferred to the suspension polymerization state through a process of latex coagulation in the forward direction, which means that the emulsion solution was dripped slowly into the suspension reaction system in the presence of coagulating agent. The dispersion status of the rubber particles in the ABS resin was studied using transmission electron microscopy, which indicated that the rubber particles were in a dispersed state in a continuous matrix of poly(styrene‐co‐acrylonitrile) when the content of rubber particles was below 20 wt%. The mechanical properties of the ABS resins obtained are as follows: elongation at break, 9.4–45.7%; yield tensile strength, 35.1–42.2 MPa; impact strength, 98.2–116.3 J m^?1. Copyright © 2006 Society of Chemical Industry     

Recycled polycarbonate/acrylonitrile–butadiene–styrene reinforced and toughened through chemical compatibilization

To improve the utilization efficiency of recycled polycarbonate/acrylonitrile–butadiene–styrene (R-PC/ABS), we studied the mechanical, morphological, and rheological properties of R-PC/ABS with styrene–butadiene–glycidyl methacrylate (SBG), which was used to reinforce and toughen the R-PC/ABS through chemical compatibilization. Fourier transform infrared spectroscopy demonstrated that carboxyl and hydroxyl groups in R-PC/ABS reacted with epoxy groups in SBG to produce ester and ether groups. The results of scanning electron microscopy show that the domain sizes of the ABS particles decreased when the SBG content was 6 wt %; this demonstrated that the compatibility of the polycarbonate (PC) and ABS was improved after the addition of SBG. The results of the loss modulus of dynamic mechanical analysis were consistent with the morphological results, which reflected a better compatibility of PC and ABS in the modified samples. The introduction of SBG increased the molecular weight and entanglements; this improved the viscosity and storage modulus in the modified samples, as demonstrated by the rheological results. Furthermore, the mechanical properties were obviously enhanced, especially the impact strength, when the SBG content was 6 wt %; this was ascribed to the chemical reactions and improved compatibility after melt extrusion with SBG. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47537.