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     

Recycling of blends of acrylonitrile–butadiene–styrene (ABS) and polyamide

The aim of this work is to evaluate routes to upgrade recycled engineering plastics, especially mixed plastics with acrylonitrile–butadiene–styrene copolymers (ABS) as the major component. A core‐shell impact modifier was successfully used to improve the impact strength of blends of ABS and ABS/polycarbonate (PC) blends recycled from the automotive industry. However, the presence of other immiscible components like polyamide (PA), even in small amounts, can lead to a deterioration in the overall properties of the blends. A styrene–maleic anhydride (SMA) copolymer and other commercial polymer blends were used to promote the compatibilization of ABS and PA. The core‐shell impact modifier was again found to be an efficient additive with regard to the impact strength of the compatibilized ABS/PA blends. The results obtained with fresh material blends were quite promising. However, in blends of recycled ABS and glass‐fiber‐reinforced PA, the impact strength did not exhibit the desired behavior. The presence of poorly bonded glass fibers in the blend matrix was the probable reason for the poor impact strength compared with that of a blend of recycled ABS and mineral‐filled PA. Although functionalized triblock rubbers (SEBS–MA) can substantially enhance the impact strength of PA, they did not improve the impact strength of ABS/PA blends because the miscibility with ABS is poor. The possibilities of using commercial polymer blends to compatibilize otherwise incompatible polymer mixtures were also explored giving promising results. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2535–2543, 2002     

Compatibility and thermal properties of poly(acrylonitrile–butadiene–styrene) copolymer blends with poly(methyl methacrylate) and poly(styrene‐co‐acrylonitrile)

The mechanical and heat‐resistant properties of acrylonitrile–butadiene–styrene (ABS) binary and ternary blends were investigated. The relationship of compatibility and properties was discussed. The results show that poly(methyl methacrylate) (PMMA) and styrene–maleic anhydride (SMA) can improve the thermal properties of conventional ABS. The Izod impact property of ABS/PMMA blends increases significantly with the addition of PMMA, whereas that of ABS/SMA blends decreases significantly with the addition of SMA. Blends mixed with high‐viscosity PMMA are characterized by higher heat‐distortion temperature (HDT), and their heat resistance is similar to that of blends mixed with SMA. For high‐viscosity PMMA, from 10 to 20%, it is clear that blends appear at the brittle–ductile transition, which is related to the compatibility of the two phases. TEM micrographs show low‐content and high‐viscosity PMMA in large, abnormally shaped forms in the matrix. Compatibility between PMMA and ABS is dependent on both the amount and the viscosity of PMMA. When the amount of high‐viscosity PMMA varied from 10 to 20 wt %, the morphology of the ABS binary blends varied from poor to satisfactory compatibility. As the viscosity of PMMA decreases, the critical amount of PMMA needed for the compatibility of the two phases also decreases. SMA, as a compatibilizer, improved the interfacial adhesiveness of ABS and PMMA, which results in PMMA having good dispersion in the matrix. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2652–2660, 2002     

Dynamic mechanical properties of polycarbonate and acrylonitrile–butadiene–styrene copolymer blends

Blends of polycarbonate (PC) and poly(acrylonitrile‐co‐butadiene‐co‐styrene) (ABS) with different compositions are characterized by means of dynamic mechanical measurements. The samples show phase separation. The shift in the temperatures of the main dynamic mechanical relaxation shown by the blend with respect to those of the pure components is attributed to the migration of oligomers present in the ABS toward the PC in the melt blending process. A comparison with other techniques (dielectric and calorimetric analysis) and the application of the Takayanagi three block model confirm this hypothesis. In all the studied blend compositions (ABS weight up to 28.6%) the PC appears as the matrix where a disperse phase of ABS is present. The scanning and transmission electron microscopy micrographs show that the size of the ABS particles increases when the proportion of ABS in the blend increases. The FTIR results indicate that the interaction between both components are nonpolar in nature and can be enhanced by the preparation procedure. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1507–1516, 2002     

Positron annihilation study of iodine sorption in acrylonitrile–butadiene–styrene

The influence of iodine on the free volume of acrylonitrile–butadiene–styrene (ABS) was investigated by positron annihilation lifetime spectroscopy (PALS). The results indicate the filling of free-volume holes, formation of a positronium–iodine compound (PsI₂/PsI), and possible charge-transfer complexes (CTCs) in the initial stages and the swelling of iodine in the final stages of sorption. The present study also revealed that iodine acts as a chemical quencher of o-Ps. The average size of the free volume suggests that I₃⁻ is the predominant species that fills up the free-volume holes during iodination. The diffusion process in the present case shows non-Fickian behavior and deviates from Fujita's free-volume concept as far as the fractional free volume and diffusion coefficient are concerned. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 2077–2085, 1998     

Effect of mixing process on electromagnetic interference shielding effectiveness of nickel/acrylonitrile–butadiene–styrene composites

This article reports the effect of the mixing process on the electromagnetic interference (EMI) shielding effectiveness of nickel/acrylonitrile–butadiene–styrene (ABS) composites. Nickel in either powder or filament form was used as the filler material. It was mixed with ABS by two mixing processes: one was the Brabender‐mixing method, in which nickel was mixed in the polymer melt by a strong shear at high temperatures, and the other was a simple dry mixing method performed in a centrifugal ball mill. Our results showed that the dry‐mixing method could produce EMI shielding effectiveness of 36 dB at the 3 vol % nickel filaments level. In contrast, we need 20 vol % nickel powder to exhibit some shielding effectiveness for the Brabender method. After the nondestructive X‐ray examination and four‐point probe resistivity measurements, we concluded that better EMI shielding effectiveness could be achieved when the mixing method provided a state of uniformity on the macroscale, but not on the microscale. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 128–135, 2005     

Recycling of acrylonitrile–butadiene–styrene and high‐impact polystyrene from waste computer equipment

Acrylonitrile–butadiene–styrene (ABS) and high‐impact polystyrene (HIPS) are two of the plastics most frequently used as outer casings for computer equipment such as monitors, keyboards, and other similar components. We assessed the effects of the recycling and blending of ABS and HIPS on mechanical properties. We found that the effects of recycling on ABS and HIPS were similar, in that changes in glass‐transition temperatures, tensile strengths, and tensile moduli were negligible, but strains to failure and impact strengths were reduced considerably. Blending proportions of ABS and HIPS caused no more deterioration in properties than occurred as a result of the recycling process, and the presence of small proportions of one material in the other actually restored significant amounts of ductility, as seen by increases in the strains to failure. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 572–578, 2002     

Observations of physical aging in a polycarbonate and acrylonitrile–butadiene–styrene blend

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 (T_g,ABS) and PC (T_g,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 T_g,PC shifts toward the stationary T_g,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     

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

The 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 (τ_w) 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 τ_w of about 200 kPa. When the temperature was fixed, the entry‐pressure drop and extensional stress increased nonlinearly with increasing τ_w, whereas it decreased with a rise of temperature at a constant level of τ_w. 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     

Fire retardant synergism of hydroquinone bis(diphenyl phosphate) and novolac phenol in acrylonitrile–butadiene–styrene copolymer

Hydroquinone bis(diphenyl phosphate) (HDP) has been adopted to prepare acrylonitrile–butadiene–styrene copolymer (ABS)/HDP/novolac phenol (NP) composites. The limiting oxygen index (LOI) of ABS/HDP/NP composites is tested in this paper. The LOI value first grows with increasing ratio of HDP to NP, after reaching its maximum it decrease with further increasing ratio. The synergistic effect of HDP and NP exerted on the microstructure and the flame retardancy of ABS/HDP/NP composites are carefully analyzed by thermogravimetric analysis (TGA), cone calorimeter (CCT), scanning electron microscope (SEM) and energy dispersive spectroscopy (EDS). The results of CCT show that the synergistic action of HDP and NP reduces its heat release rate and smoke production rate. The results of TGA and SEM demonstrated that the introduction of NP and HDP is conducive to the improvement of the thermal stability and the formation of the intumescent char with homogeneous cavities and holes. The EDS results indicate that the introduction of NP could help retain phosphorus in the chars. As a result, the synergistic action of HDP and NP is favorable to the enhancement of flame retardancy of ABS/HDP/NP composites. Copyright © 2014 John Wiley & Sons, Ltd.     

Organic–inorganic composite materials from acrylonitrile–butadiene–styrene copolymers (ABS) and silica through an in situ sol‐gel process

Nonbonded and chemically bonded organic–inorganic composite materials, ABS/SiO₂ and ABS Si(OCH₃)₃/SiO₂, were prepared by the sol‐gel processing of tetraethoxysilane (TEOS) in the presence of ABS and trimethoxysilyl functionalized ABS, ABS Si(OCH₃)₃, under the catalization of NH₄F. The ABS Si(OCH₃)₃ was obtained by oxidizing the cyano group in ABS with hydrogen peroxide, then subsequently underwent ring‐opening reaction with 3‐glycidoxypropyltrimethoxysilane (GPTS). The ABS Si(OCH₃)₃/TEOS sol‐gel liquid solution system, in which the ABS chains formed the covalent bonds with silica network and helped fix the polymer chains in the silica network, had a shorter gelation time than that of the ABS/TEOS system, which linked ABS chains to the silica network only by hydrogen bonding the cyano groups in ABS to the silanol groups. The morphology and properties of composite were characterized by scanning electron microscopy (SEM), differential scanning calorimeter (DSC), tensile tests, and thermogravimetry. It was found that the composite prepared from ABS Si(OCH₃)₃ had higher tensile strength, glass transition point (T_g), thermal stability, and more homogeneous morphology because of the existence of the covalent bond between ABS chains and silica network that increased the compatibility between the organic and inorganic phases. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 275–283, 2000     

Study on the microphase structure and mechanical properties of the blends of acrylonitrile–butadiene–styrene and sodium sulphonated styrene–acrylonitrile ionomer

The tensile properties of the blends containing neat acrylonitrile–butadiene–styrene (ABS), styrene–acrylonitrile (SAN) and the sodium sulphonated SAN ionomer have been investigated as a function of ion content of the ionomer in the blend. The tensile toughness and strength of the blends showed maximum values at a certain ion content of the ionomer in the blend. This is attributed to the enhanced tensile properties of the SAN ionomer by introduction of ionic groups into SAN and the interfacial adhesion between the rubber and matrix phase in the blend. The interfacial adhesion was quantified by NMR solid echo experiments. The amount of interphase for the blend containing the SAN ionomer with low ion content (3·1mol%) was nearly the same as that of ABS, but it decreased with the ion content of the ionomer for the blend with ion content greater than 3·1mol%. Changing the ionomer content in the blends showed a positive deviation from the rule of mixtures in tensile properties of the blends containing the SAN ionomer with low ion content. This seems to result from the enhanced tensile properties of the SAN ionomer, interfacial adhesion between the rubber and matrix, and the stress concentration effect of the secondary particles. © 1998 SCI.     

Synthesis,flame‐retardancy testing,and preliminary mechanism studies of nonhalogenated aromatic boronic acids: A new class of condensed‐phase polymer flame‐retardant additives for acrylonitrile–butadiene–styrene and polycarbonate

This study describes the syntheses and thermal properties of aromatic boronic acids and their use as flame retardants. The possible flame‐retardancy mechanisms are also discussed. The materials were synthesized from aromatic bromides using one of two procedures. The first procedure involved traditional approaches to boronic acids, using lithium–halogen exchange and quenching with trimethylborate followed by hydrolysis. The second procedure used a nickel catalyst and a dialkoxy borane to generate aromatic dialkoxyboronates that were converted to boronic acids by acid hydrolysis. The thermal properties of these aromatic boronic acids were studied using differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). These materials were blended into acrylonitrile–butadiene–styrene (ABS) and polycarbonate (PC) resins and tested for ignition resistance, using the UL‐94 flame test. A 10 wt % loading of 1,4‐benzenediboronic acid in polycarbonate gave a UL‐94 V‐0 result. This same diboronic acid showed flame retardancy and char formation in ABS, but this result was not quantifiable by the UL‐94 test. Burn times for the ABS samples often exceeded 5 min, thereby showing unusual resistance to consumption by fire. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 1257–1268, 2000     

Polymer blends with modified coupling agent. II. Effects of LICA 44 grafted styrene–maleic anhydride copolymer on properties of flame retardant acrylonitrile–butadiene–styrene blends

Flame retardant acrylonitrile–butadiene–styrene (FR‐ABS) blends were prepared by blending tetrabromobisphenol A (TBBA) and antimony trioxide (Sb₂O₃) into the ABS resin. LICA 44 grafted styrene–maleic anhydride (SMA‐g‐L44) copolymers were used as high molecular weight (MW) coupling agents to modify the properties of the FR‐ABS blends, and the copolymers with different LICA 44 grafting ratios were produced via the in vivo and the in situ reactions, respectively. The LICA 44 percentage and the MW of the SMA‐g‐L44 copolymers are important factors influencing the effects of the high MW coupling agent. The impact strength and the tensile yield stress of SMA‐g‐L44 modified FR‐ABS blends increased obviously. The elongation at break and the limiting oxygen index of which also showed an increasing trend after the modification. The coupling effect of SMA‐g‐L44 became weaker at a higher grafting ratio. SEM observation showed that the interfacial boundary in the FR‐ABS became fuzzy after using the SMA‐g‐L44 copolymers. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 865–874, 1999     

Characterisation of gamma‐irradiated polyetherimide films with infrared spectroscopy and thermally stimulated current measurements

The performance of insulators is usually affected by the presence of space charges. The evolution of these charges under applied constraints in many cases leads to the degradation of these materials. To evaluate the performance of an insulator it is necessary to study the evolution of the physical and chemical properties in the presence of space charges. In this paper, the effect of gamma irradiation on the space charge behaviour in polyetherimide (PEI; Ultem 1000) has been investigated at different radiation doses. Space charge measurements were made using thermally stimulated currents. Infrared spectroscopy characterisation was performed to investigate the effect of gamma irradiation on the physicochemical properties of PEI. The results obtained show minor differences in the infrared spectra, mainly in the 410 cm^?1 region. It is found that irradiation leads to a few structural changes in the material. The thermostimulated depolarisation current (TSDC) results show that β relaxations in PEI are affected by gamma irradiation. The activation energies of dipoles were calculated from the TSDC curves. Copyright © 2006 Society of Chemical Industry     

Synthesis and properties of vinyltrimethoxysilane–EPDM–styrene graft terpolymer

The graft copolymerizations of vinyltrimethoxysilane (VTMO) and styrene (St) onto ethylene–propylene–diene terpolymer (EPDM) were carried out with benzoyl peroxide (BPO) as an initiator in toluene. The effects of EPDM concentration, mole ratio of VTMO to St, reaction time, reaction temperature, and initiator concentration on the graft copolymerizations were examined. The synthesized VTMO–EPDM–St graft terpolymers (VES) were confirmed by infrared and ¹H-NMR spectroscopies. The molecular weight, thermal stability, light resistance, and weatherability of the graft terpolymer were investigated by gel permeation chromatography, thermogravimetric analysis, and Fade-o-Meter. The number-average molecular weight was 109,000. It was found that the heat resistance and light resistance as well as weatherability of VES are considerably better than those of acrylonitrile–butadiene–styrene terpolymer. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67:1345–1352, 1998     

Morphology of pyrolysed polystyrene–isoprene–styrene and polystyrene–butadiene–styrene block copolymers

The surface morphology of thermooxidative degraded polystyrene–isoprene–styrene (SIS) and polystyrene–butadiene–styrene (SBS) thermoplastic block copolymers was studied by scanning electron microscopy. Surface changes caused by heating the samples in a pyrolyzer for 15 and 30 min were presented in different micrographs. The morphological changes occurring due to the formation of polar groups and their crosslinking during the thermooxidative degradation are discussed. Morphological study of these thermally degraded polymer samples shows very good correlation with the thermodegradation results. The rate of thermodegradation is fast in case of SBS when compared with SIS block copolymer. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 2549–2553, 2006     

Morphology of pyrolyzed polystyrene–isoprene–styrene and polystyrene–butadiene–styrene block copolymers

The surface morphology of thermooxidative‐degraded polystyrene–isoprene–styrene (SIS) and polystyrene–butadiene–styrene (SBS) thermoplastic block copolymers were studied by scanning electron microscopy. Surface changes caused by heating the samples in a pyrolizer for 15 and 30 min were presented in different micrographs. The morphological changes occurring due to the formation of polar groups and their crossing linking during the thermooxidative degradation are discussed. Morphological study of these thermally degraded polymer samples show very good correlation with the thermodegradation results. The rate of thermodegradation is fast in case of SBS compared with SIS block copolymer. ©2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006     

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     

Novel method for preparation of quaternary ammonium ionomer from epoxidized styrene–butadiene–styrene triblock copolymer and its use as compatibilizer for blending of styrene–butadiene–styrene and chlorosulfonated polyethylene

A novel method for the preparation of a quaternary ammonium ionomer of styrene–butadiene–styrene triblock copolymer (SBS) was developed by a ring‐opening reaction of epoxidized SBS with triethylamine hydrochloride in the presence of a phase transfer catalyst. The optimum conditions were studied. The ionomer was characterized by quantitative analysis, IR spectroscopy, and ¹H‐NMR spectroscopy. Its water absorbency, oil absorbency, dilute solution viscosity, and use as a compatibilizer for the blending of SBS and chlorosulfonated polyethylene (CSPE) were investigated. The results showed that, under optimum conditions, the epoxy groups can be completely converted to the quaternary ammonium groups. The IR spectrum did not exhibit the absorption peak for quaternary ammonium groups, whereas the ¹H‐NMR spectrum and titration method demonstrated it. With increasing ionic group content, the water absorbency of the ionomer increased whereas its oil absorbency decreased. These indicated the amphiphilic character of the SBS ionomer. The dilute solution viscosity of the ionomer in toluene/methanol (9/1) solvent increased with increasing quaternary ammonium group content. The ionomer was used as a compatibilizer for the blends of SBS and CSPE. The addition of a small amount of the ionomer to the blend enhanced the mechanical properties of the blends: 2 wt % ionomer based on the blend increased the tensile strength and ultimate elongation of the blend nearly 2 times. The blends of equal parts SBS and CSPE behaved as oil‐resistant thermoplastic elastomers. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1975–1980, 2006