Acrylonitrile Butadiene Styrene Terpolymer Research Articles

Effect of Reprocessing and Accelerated Weathering on ABS Properties

The feasibility of reprocessing has been investigated as a possible alternative for acrylonitrile–butadiene–styrene terpolymer (ABS) recycling. Up to 10 reprocessing cycles have been performed by both extrusion and injection techniques and their effect on thermal and mechanical properties have been studied. Moreover, the effect of the combined reprocessing and accelerated weathering has been analyzed. Measurements collected after each molding cycle indicated virtually complete retention of thermal properties. The same behaviour has been observed from accelerated weathering tests. With respect to the mechanical properties, neither the flow index nor the tensile strength were affected by the number of reprocessing cycles though the impact strength decreased slightly. However, the studies based on the accelerated weathering show that there is an important influence of the number of reprocessing cycles on the tensile strength.

Structural analysis of multicomponent nanoclay-containing polymer blends through simple model systems

A systematic approach was adopted to study multicomponent clay-containing nanocomposites using compatibilized and non-compatibilized blends of polyamide 6 (PA6)/acrylonitrile–butadiene–styrene terpolymer (ABS) and their organoclay (OMMT) nanocomposites. For this purpose PA6/styrene–acrylonitrile copolymer (SAN) based blends and nanocomposites were selected as simple model systems. In this way the role of each component of the systems, especially the clay, compatibilizer, and polybutadiene fraction on the formation of intercalated or exfoliated OMMT structures as well as resulting dynamic mechanical properties (DMA) could be elucidated. Structural analysis of the model systems using theoretical approach, and X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and DMA revealed that the most crucial factor in controlling the morphology and achieving different levels of dispersion is the extent of interaction between clay and the polymer matrix. Morphological analysis revealed that the OMMT layers were dispersed and exfoliated largely in the PA6 phase but, some were also accumulated at the rubber particle surface which remained non-intercalated. The effect of a compatibilizer on the dispersion of OMMT was not completely clear. The SAN based nanocomposites containing PA6 showed fully exfoliated OMMT structures, whereas the ABS based nanocomposites, having an additional rubber fraction, showed a mixed exfoliated and also partly non-intercalated morphology. The OMMT did not change the general occurrence of the co-continuous structures but refined the structures and led to mechanical stiffening as indicated by the DMA results. A correlation was established between the changes in the morphological states and the DMA properties.

Comparative study on the homogeneity of polymeric calibration materials using LA-ICP-MS

The production of polymeric calibration standard materials with sufficient homogeneity for the calibration of analytical methods with high lateral resolution like LA-ICP-MS was investigated. An index η* was introduced to compare the homogeneities of different acrylonitrile butadiene styrene terpolymer (ABS) based samples. It was demonstrated, that elements present in organic compounds could be introduced into polymeric materials with a higher homogeneity than inorganic compounds without special treatment. For organic Br compounds, a 20 to 30 times higher value for η* was found than it was for the case of AgBr. For Pb stearate and Pb acetate, 10 times higher values for η* were found than was the case for PbCrO4. For PbO, it is shown that multiple extrusion and mechanical treatment can improve the homogeneity of certain inorganic compounds as particle sizes are decreased during the extrusion.

Effect of order of mixing on morphology and thermal properties of the compatibilized PBT and ABS alloys/OMT nanocomposites

AbstractPoly(butylene terephthalate) (PBT) and acrylonitrile–butadiene–styrene terpolymers (ABS) alloys/organically modified montmorillonite (OMT) nanocomposites using terpolymers of random ethylene, methyl acrylate, and glycidyl methacrylate as the reactive compatibilizer were prepared by different melt‐mixing sequences. The microstructures were characterized by scanning electron microscopy, X‐ray diffraction, transmission electron microscopy, and high‐resolution electron microscopy. It was found that order of mixing affects the dispersion state of OMT in the alloy matrix. The crystallization behavior of PBT in the compatibilized PBT and ABS alloys/OMT nanocomposites was studied by wide angle X‐ray diffraction. It revealed that order of mixing has influence on the preferential crystal growing direction of PBT owing to the antagonistic effect of ABS and OMT. Thermogravimetric analyses and differential scanning calorimetry also showed order of mixing changes the thermal property of the compatibilized PBT and ABS alloys/OMT nanocomposites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2130–2139, 2007

Development of suitable plastic standards for X-ray fluorescence analysis

For the adoption of the EU directive “Restriction on use of certain Hazardous Substances” and “Waste Electrical and Electronic Equipment” using X-ray fluorescence analysis suitable standard materials are required. Plastic standards based on acrylonitrile–butadiene–styrene terpolymer, containing the regulated elements Br, Cd, Cr, Hg and Pb were developed and produced as granulates and solid bodies. The calibration materials were not generated as a dilution from one master batch but rather the element concentrations were distributed over nine independent calibration samples. This was necessary to enable inter-elemental corrections and empirical constant mass absorption coefficients. The produced standard materials are characterized by a homogenous element distribution, which is more than sufficient for X-ray fluorescence analysis. Concentrations for all elements except for Br could be determined by Inductively Coupled Plasma Atomic Emission Spectroscopy after microwave assisted digestion. The concentration of Br was determined by use of Neutron Activation Analysis at Hahn-Meitner-Institute in Berlin, Germany. The correlation of the X-ray fluorescence analysis measurements with the values determined using Inductively Coupled Plasma Atomic Emission Spectroscopy and Neutron Activation Analysis showed a very good linearity.

Phase morphology development during processing of compatibilized and uncompatibilized PBT/ABS blends

AbstractThe development of the multiphase morphology of uncompatibilized blends of poly(butylene terephthalate) (PBT) and acrylonitrile–butadiene–styrene terpolymer (ABS) and PBT/ABS blends compatibilized with methyl‐methacrylate glycidyl‐methacrylate (MMA‐GMA) reactive copolymers during compounding in a twin‐screw extruder and subsequent injection molding was investigated. Uncompatibilized PBT/ABS 60/40 (wt %) and compatibilized PBT/ABS/MMA‐GMA with 2 and 5 wt % of MMA‐GMA showed refined cocontinuous morphologies at the front end of the extruder, which coarsened towards the extruder outlet. Coarsening in uncompatibilized PBT/ABS blends is much more pronounced than in the compatibilized PBT/ABS/MMA‐GMA equivalents and decreases with increasing amounts of the MMA‐GMA. For both systems, significant refinement on the phase morphology was found to occur after the blends pass through the extruder die. This phenomenon was correlated to the capacity of the die in promoting particles break‐up due to the extra elongational stresses developed at the matrix entrance. Injection molding induces coarsening of the ABS domains in the case of uncompatibilized PBT/ABS blends, while the reactive blend kept its refined phase morphology. Therefore, the compatibilization process of PBT/ABS/MMA‐GMA blends take place progressively leading to a further refinement of the phase morphology in the latter steps, owing to the slow reaction rate relative to epoxide functions and the carboxyl/hydroxyl groups. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 102–110, 2007

Fracture toughness of thermoplastic co-poly (ether ester) elastomer—Acrylonitrile butadiene styrene terpolymer blends

Acrylonitrile butadiene styrene terpolymer (ABS) was blended with thermoplastic co-poly (ether ester) elastomer (COPE) in different weight ratios in a twin screw extruder. Fracture toughness of the blends as a function of COPE weight percentage was studied. Fracture toughness was investigated using the J-integral by locus method developed by Kim et al. [B.H. Kim, C.R. Joe, D.M. Otterson, Polym. Test. 8 (1989) 119]. The fracture toughness of the blend with 5 wt% shows higher fracture toughness than pure ABS. The correlation of the topology of the fracture surface with the fracture toughness of the blends was carried out. The physical properties of the blends were studied. The addition of COPE improves the impact property, while flexural modulus shows a slight increase when ABS is blended with COPE at low concentration. The SEM micrographs show three-phase morphology.

Flammability of styrenic polymer clay nanocomposites based on a methyl methacrylate oligomerically-modified clay

Nanocomposites of polystyrene, high impact polystyrene, acrylonitrile–butadiene–styrene terpolymer, polypropylene, and polyethylene were prepared using a methyl methacrylate oligomerically-modified clay by melt blending and the thermal stability and fire retardancy were studied. These nanocomposites were characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis and cone calorimetry. The results show a mixed morphology, depending on the polymer.

Solvothermal preparation of maleic anhydride grafted onto acrylonitrile–butadiene–styrene terpolymer (ABS)

The grafting copolymerization of maleic anhydride (MAH) onto acrylonitrile–butadiene–styrene terpolymer (ABS) was carried out through solvothermal process. Infrared (IR) spectra and 1H NMR spectra confirmed that maleic anhydride was successfully grafted onto the ABS backbone. The influences, such as MAH concentration, the initiator's content, reaction temperature and time, comonomer, ABS concentration and different solvents, on the grafting copolymerization were also studied. Results indicated that the preparation of MAH grafted onto ABS through solvothermal method can be carried out in both good solvent and poor solvent, which is much different from the traditional solution grafting method, and high grafting degree can be obtained in good solvent.

The preparation and properties of compatibilized nylon 6/ABS blends using functionalized polybutadiene. Part I: Impact properties

The impact behaviors of nanoclay filled nylon 6 (nano-nylon 6) or nylon 6 blended with poly(acrylonitrile-butadiene-styrene) terpolymers (ABS) were investigated here using polybutadiene grafted maleic anhydride (PB-g-MA) as a compatibilizer to enhance interphase interaction. It is found that impact strength increases slightly for nano-nylon 6/ABS blend system with the addition of compatibilizer at various ABS compositions, but increases to a certain degree for nylon 6/ABS case. Similar effects are also found with decreasing test temperature, especially at a blend composition of 80/20. These discrepancies are attributed to a different degree of available reaction sites from amine group on nano-nylon 6 and nylon 6 as well as the rigidity of clay in deteriorating toughness. As for thermal properties, the heat distortion temperature shows marginally decrease in the nano-nylon 6/ABS blend. Through morphology observations, the etched ABS particle sizes tend to decrease with the additions of compatibilizer for both blends, but are larger with higher contents of ABS concentrations. Those observations account for impact behaviors of the investigated blends. POLYM. ENG. SCI., 45:1461–1470, 2005. © 2005 Society of Plastics Engineers

Polybutadiene-modified clay and its nanocomposites

A butadiene-modified clay was prepared by ionic exchange between sodium montmorillonite and a butadiene surfactant; the butadiene surfactant was obtained from the reaction of vinylbenzyl chloride grafted polybutadiene with a tertiary amine. Nanocomposites of polystyrene, high impact polystyrene, acrylonitrile–butadiene–styrene terpolymer, poly(methyl methacrylate), polypropylene and polyethylene were prepared by melt blending this modified clay with the virgin polymers. The nanocomposites were characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis, cone calorimetry and the evaluation of mechanical properties. A morphological study of PBD-modified clay–polymer nanocomposites shows that all the composites are immiscible micro-composites. The consistency of the result from XRD and TEM with that of cone calorimetry indicates that the cone calorimeter must also be considered as another method to examine the bulk sample and infer if good dispersion of the clay in the polymer has been achieved. The mechanical properties of the nanocomposites prepared from different methods show that the mechanical properties are, in general, predictable based on the type of dispersion.

Thermorheological studies of novel thermoplastic elastomeric blends of nitrile rubber (NBR) and scrap computer plastics (SCP) based on acrylonitrile–butadiene–styrene terpolymer (ABS)

Thermorheological properties of thermoplastic elastomeric 60/40, 70/30 and 80/20 nitrile rubber (NBR)/scrap computer plastics (SCP) blends were studied by using parallel plate rheometer. The blends exhibit pseudoplasticity and obey power law model. The dynamically vulcanised blends have higher dynamic viscosities than their unvulcanised counterparts. Surface finish and die swell of the extrudates are improved upon dynamic vulcanisation. The thermoplastic elastomeric blends of NBR/SCP exhibit 'thermorheological complexity'.

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

AbstractThe 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

Kinetics and mechanism of grafting of crotonic acid onto acrylonitrile–butadiene–styrene terpolymer

AbstractThe grafting of crotonic acid onto acrylonitrile‐butadiene‐styrene terpolymer (ABS) was initiated by benzoyl peroxide (BPO) in 1,2‐dichloroethane solution. The infrared spectra confirmed that crotonic acid was successfully grafted onto ABS backbone. The influences of the concentration of crotonic acid, BPO, and ABS on grafting were studied. The graft occurred at the butadiene region of ABS. A reaction mechanism was proposed: the grafting most likely took place by cross‐termination of poly(crotonic acid) radicals with ABS macroradicals. The initial rate of grafting could be written as: Rp = 2.02 × 10−4[P][M] 2[I2]0.5/([M] + 1.05[P])2. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 726–733, 2002

Effects of extrusion conditions on rheological behavior of acrylonitrile–butadiene–styrene terpolymer melt

AbstractThe influence of temperatures and flow rates on the rheological behavior during extrusion of acrylonitrile–butadiene–styrene (ABS) terpolymer melt was investigated by using a Rosand capillary rheometer. It was found that the wall shear stress (τw) increased nonlinearly with increasing apparent shear rates and the slope of the curves changed suddenly at a shear rate of about 103 s−1, whereas the melt‐shear viscosity decreased quickly at a τw of about 200 kPa. When the temperature was fixed, the entry‐pressure drop and extensional stress increased nonlinearly with increasing τw, whereas it decreased with a rise of temperature at a constant level of τw. The relationship between the melt‐shear viscosity and temperature was consistent with an Arrhenius expression. The results showed that the effects of extrusion operation conditions on the rheological behavior of the ABS resin melt were significant and were attributable to the change of morphology of the rubber phase over a wide range of shear rates. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 606–611, 2002

Multicomponent blends based on polyamide 6 and styrenic polymers: morphology and melt rheology

The role of each blend component on blend morphology and melt rheological properties was investigated for multicomponent compatibilized blends of polyamide 6 (PA6) and acrylonitrile–butadiene–styrene terpolymer (ABS). Blends with PA6 content of 50 wt% were prepared at similar processing conditions on a ZSK 30 twin screw extruder. PA6/styrene–acrylonitrile co-polymer (SAN) blends showed a dispersed morphology with PA6 as matrix. Addition of reactive compatibilizer, styrene–acrylonitrile–maleic anhydride co-polymer (SANMA), up to 5 wt%, changed the morphology from a dispersed to a co-continuous structure. PA6/ABS, having a part of the SAN substituted by rubber, exhibited a coarse co-continuous structure which could be explained with the yield stress of the ABS. Addition of the compatibilizer to this system refined the co-continuous structure and increased the viscosity as well as the elasticity.

Grafting of long‐chain unsaturated carboxylic acids onto acrylonitrile–butadiene–styrene terpolymer

AbstractThe graft copolymerization of undecylenic acid, oleic acid, and crotonic acid onto acrylonitrile–butadiene–styrene terpolymer (ABS) was initiated by benzoyl peroxide (BPO) in 1,2‐dichloroethane solution. The infrared spectra confirmed that undecylenic acid, oleic acid, and crotonic acid were successfully grafted onto the ABS backbone. The grafting occurred at the butadiene region of the ABS. The grafting degree increased with increasing monomer concentration, but it decreased after monomer concentration, reaching 0.30 mol/L in undecylenic acid and oleic acid systems. The grafting degree increased rapidly with increasing initiator concentration, but slowed down at about 0.012 mol/L of initiator concentration. The grafting degree decreased considerably with increasing ABS concentration; however, the total amount of grafted monomer increased. Increasing reaction time and temperature led to an increase in grafting degree. The chain length of the monomer has a great influence on grafting. The grafting degree decreases with increasing the chain length due to a steric hindrance and monomer cage effect, which is in agreement with activation energy calculation. The overall activation energy of crotonic acid, undecylenic acid, and oleic acid systems are 118, 122, and 134 kJ/mol, respectively. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1934–1939, 2002

A new hybrid nanocomposite prepared by emulsion copolymerization of ABS in the presence of clay

The preparation and characterizations of new hybrid organic–inorganic nanocomposites consisting of acrylonitrile–butadiene–styrene terpolymer and a Na+-exchanged montmorillonite (MMT) are described by direct intercalation through one-step emulsion polymerization. Those products were purified by successive hot acetone and toluene extraction, respectively, for more than 2 days. The IR spectra for the purified samples revealed the characteristic absorbances as a result of those of styrene, butadiene, acrylonitrile, and MMT. X-ray diffraction spectra of the composites showed the enlarged 001 d-spacing as much as 1.75 nm, but no signals were found for the partial insertion of copolymer chains. Moreover, it was evident that this direct intercalation was not accompanied by delamination of the clay interlayer. The thermogravimetric analytic measurement for the purified product confirmed that the onset temperature of decomposition was transferred to the higher temperature region as much as 40–50 °C. Morphological observations by transmission electron microscopy, scanning electron microscopy, and optical micrography demonstrated homogeneous dispersion of MMT particles in the copolymer matrix. The possible physical picture of this direct intercalation was discussed in terms of swelling characteristics of compacted bentonite and the monomer containing micelle sizes. © 2001 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 719–727, 2001

Thermal degradation of acrylonitrile–butadiene–styrene terpolymer in bean oil

Thermal degradation of acrylonitrile–butadiene–styrene terpolymer (ABS) in bean oil has been carried out in the temperature 350 and 370°C. The degradation products have been investigated by means of gel permeation chromatography (GPC) and fourier transform infra-red spectrometry (FTIR). With the presence of bean oil, ABS thermally degrades into asphalt-like degradation residue, which is soluble in common organic solvent such as tetrahydrofuran (THF), instead of monomer and oligomers that are usually generated in direct pyrolysis of ABS. Moreover, for the system of ABS/bean oil the cross-linking reaction of ABS with bean oil takes place and forms a polymer network before the decomposition of ABS. Between the two reaction stages, the polymerization or oligomerization of sequence of adjacent nitrile groups occurs. The thermal degradation of ABS in bean oil was believed to be a radical process, which is dependent on the reaction condition, especially the concentration of bean oil, reaction temperature and time.

Effect of crosslinking reactions and order of mixing on properties of compatibilized PBT/ABS blends

The low-temperature notched Izod impact strength of poly(butylene terephthalate), PBT, blends with acrylonitrile–butadiene–styrene terpolymers, ABS, can be improved by incorporating methyl methacrylate, glycidyl methacrylate, ethyl acrylate terpolymers, MGE, as a reactive compatibilizer. However, fracture properties depend on the order of mixing of the blend components. When all components of compatibilized blends are melt mixed together in a single-pass extrusion, the low-temperature toughness is improved; however, the room-temperature impact strength is reduced relative to uncompatibilized blends. Using a two-pass extrusion method where PBT and MGE are melt mixed together in a first extrusion prior to incorporating ABS in a second extrusion, the room-temperature impact strength is superior to that of blends prepared by the single-pass method. When a two-pass method is used where ABS and MGE are combined prior to extrusion with PBT, the impact properties at all temperatures are inferior to those of uncompatibilized blends. Evidence is presented which suggests that residual acids present in emulsion-made ABS material may cause a crosslinking reaction involving the epoxide functionality of MGE terpolymers resulting in a deleterious effect on the ABS mechanical properties and its blends with PBT. By changing the order of mixing, the sequence of chemical reactions which occur can be controlled to optimize blend properties.