SAN Matrix Research Articles

Unexpected super anti-compressive styrene-acrylonitrile copolymer/polyurea nanocomposite foam with excellent solvent resistance, re-processability and shape memory performance

High-performance, recycling and environmental protection are the goal of the development of polymer materials in the future. The introduction of crosslinking and composite are two main ways to improve the comprehensive properties of materials, however, which leads to the non-recyclability of materials or brings difficulties to the recovery process. Here, we report a polymer nanocomposite foam with superior compression properties to most existing commercial foams, just originating from common commercial styrene-acrylonitrile copolymer (SAN) and polyurea (PUA), and develop a green and energy-efficient method to fabricate high-performance rigid foam by reactive plasticizing and reaction induced phase-separation combining with supercritical CO2 (sc-CO2) foaming. Reaction induced phase-separation results in the in-situ formation of nanoscale structure in the cell walls of the resultant foams, in which the crosslinked PUA is the dispersed phase with the size of 10–40 nm in the matrix of SAN. Optimizing crosslinking network structure of PUA dramatically improve the comprehensive performance of SAN/PUA nanocomposite foams. The resultant SAN/PUA nanocomposite foam shows some performance characteristic of thermosetting polymers, such as excellent heat resistance and solvent resistance than the SAN matrix, meanwhile the performance characteristic of thermoplastic polymers, such as re-processability. More interestingly, the SAN/PUA nanocomposite foam presents excellent shape memory performance. With the above exceptional performances, this polymer nanocomposite foam will be a perfect substitute for the existing commercial rigid foams.

Acrylonitrile-Styrene-Acrylate Particles with Different Microstructure for Improving the Toughness of Poly(styrene-co-acrylonitrile) Resin

Herein, acrylonitrile-styrene-acrylate copolymer (ASA) particles with different microstructure were synthesized by emulsion polymerization and then used for toughening poly(styrene-co-acrylonitrile) (SAN) resin. The structure of ASA particles was confirmed by FTIR. TEM results demonstrated that the particles with different morphologies of multilobe shape, complete core-shell and dumbbell shape were obtained depending on the cross-linker amount. It was found that the toughening efficiency reached the highest when the ASA particles had complete core-shell structure and the shell composition was close to that of the SAN matrix. It was ascribed to the fact that the complete shell layer and similar shell composition provided sufficient interfacial adhesion and transferred stress to induce larger matrix deformation, so that the notched impact strength increased accordingly. Moreover, the notched impact strength of SAN/ASA blend was improved without significantly sacrificing tensile strength when adding 30 wt% ASA particles with the size of around 400 nm. SEM results of the impact-fractured surfaces revealed that irregular fluctuation and numerous microvoids occurred. It was deduced that the toughening mechanism was attributed to the crazings and cavitation of particles. Therefore, this study paved a way of toughening the resin by adjusting the microstructure of the particles including morphology, composition, and size.

Interfacial Compatibilization in Ternary Polymer Nanocomposites: Comparing Theory and Experiments

In this work, we examine binary and ternary nanocomposites of poly(methyl methacrylate) grafted silica nanoparticles (PMMA-NP), in poly(styrene-ran-acrylonitrile) (SAN), and poly(methyl methacrylate) matrices as a platform to directly probe governing parameters guiding phase behavior and nanoparticle assembly in composite materials. Through the addition of PMMA matrix chains similar in molecular weight to the grafted PMMA chains and significantly smaller than the SAN matrix chains, we observe increased nanoparticle miscibility in off-critical compositions due to interfacial segregation of PMMA matrix chains. A simple interfacial model provides a general guideline for predicting the extent of compatibilization. Further insights on compatibilization behavior are provided by polymer particle pair correlation functions and structure factors obtained using polymer reference interaction site model theory calculations as well as polymer concentration profiles from molecular dynamics simulations. This study serves as a guideline to facilitate PNC processing and design of materials for a broad range of technological applications.

The impact of Janus nanoparticles on the compatibilization of immiscible polymer blends under technologically relevant conditions.

Several hundred grams of Janus nanoparticles (d ≈ 40 nm) were synthesized from triblock terpolymers as compatibilizers for blending of technologically relevant polymers, PPE and SAN, on industry-scale extruders. The Janus nanoparticles (JPs) demonstrate superior compatibilization capabilities compared to the corresponding triblock terpolymer, attributed to the combined intrinsic properties, amphiphilicity and the Pickering effect. Straightforward mixing and extrusion protocols yield multiscale blend morphologies with "raspberry-like" structures of JPs-covered PPE phases in a SAN matrix. The JPs densely pack at the blend interface providing the necessary steric repulsion to suppress droplet coagulation during processing. We determine the efficiency of JP-compatibilization by droplet size evaluation and find the smallest average droplet size of d ≈ 300 nm at 10 wt % of added compatibilizer, whereas at 2 wt %, use of JPs is most economic with reasonable small droplets and narrow dispersity. In case of excess JPs, rheological properties of the system is changed by a droplet network formation. The large-scale synthesis of JPs, the low required weight fractions and their exceptional stability against extensive shear and temperature profiles during industrial extrusion process make JP promising next generation compatibilizers.

Ultralow Electrical Percolation Threshold in Poly(styrene-co-acrylonitrile)/Carbon Nanotube Nanocomposites

Here, we demonstrate a new method that involves in situ copolymerization of styrene and acrylonitrile monomers in the presence of multiwall carbon nanotubes (MWCNTs) and commercial poly(styrene-co-acrylonitrile) (SAN) beads, for the preparation of electrically conducting SAN/MWCNT nanocomposites with a significantly low percolation threshold of the CNTs. At a constant CNT loading, the conductivity of the nanocomposites was increased with increasing content (weight percent) of the SAN beads, indicating the formation of a more continuous network structure of the CNTs in SAN matrix. Thus, the electrical conductivity (1.38 × 10–6 S·cm–1) of the nanocomposites with 40 wt % SAN beads increased to 8.07 × 10–5 S·cm–1 when the SAN bead content was increased to 70 wt % at constant CNT loading (i.e., 0.1 wt %). The morphology study revealed the dispersion and distribution of the MWCNTs selectively in the in situ polymerized SAN phase of the nanocomposites, leading to an increase in effective concentration of the CNTs in the in situ polymerized SAN phase of the nanocomposites. Thus, the percolation threshold of the nanocomposites was reduced to a lower value (0.032 wt % MWCNT), which was not reported elsewhere for SAN/MWCNT nanocomposites with unmodified, commercial MWCNTs of similar qualities. This report discusses detailed methodology of the process as well as other characteristics of the SAN/MWCNT nanocomposites.

Preparation and Property Study of PMMA/ASA Alloy

Polymethyl methacrylate (PMMA)/ acrylonitrile-styrene-acrylate terpolymer (ASA) alloy was prepared via melt blending method. Effects of ASA melt flow rate and PMMA/ASA ratio on mechanical property of the alloy were studied. It showed that when the high melt flow rate ASA was used, alloy’s tensile strength and flexural strength were little different from using low melt flow rate ASA, while the impact strength was significantly higher than the latter. Differential scanning calorimetry (DSC) analysis showed that a glass transition (Tg) platform emerged in low melt flow rate ASA at 48.5°C, which represented the Tg of the interface phase formed between SAN grafted acrylate rubber particles and SAN matrix. Scanning electron microscope (SEM) experiment further showed that when low melt flow rate ASA was used, alloy’s cross section was smooth which showed the characteristics of brittle fracture.

Synthesis and characterization of electrically conductive composite films of polypyrrole/poly(acrylonitrile-co-styrene)

Homogeneus Polypyrrole (PPy)/poly(acrylonitrile-co-styrene) (SAN) composite thin films were prepared by chemical polymerization of pyrrole on poly(acrylonitrile-co-styrene) matrix. Ce (IV) is used as an oxidant for in-situ polymerizion of pyrrole on SAN matrix, having an advantageous over the impregnation method. The formation and incorporation of PPy in the copolymer matrix were confirmed by FTIR-ATR and UV-Visible spectrophotometric measurements. Thermal analyses showed that after polymerization of Py in copolymer matrix, thermal behavior of SAN was changed and derivative of weight loss at this temperature was increased by increasing of PPy content. XPS and FTIR-ATR analysis of composite films indicated cerium salt with nitrate ion acted as a dopant. The increase in the AC electrical conductivity of the PPy/SAN composites over pure SAN was observed. At lower frequency up to 105 Hz, conductivity was shown an independent behavior from frequency; but at high frequencies (105–107 Hz), dependence on frequency was explained by polaron and bipolaron formations of PPy. The dispersion of PPy particles in copolymer matrix was proven by SEM, AFM and digital camera. By the increase of PPy content in the composite films, increase in AC conductivities, and decrease in dielectric constants and loss were observed.

Noncovalent functionalization of multiwalled carbon nanotubes using graft copolymer with naphthalene and its application as a reinforcing filler for poly(styrene‐co‐acrylonitrile)

AbstractA new compatibilizer, poly(vinyl benzyloxy ethyl naphthalene)‐graft‐poly(methyl methacrylate), for poly(styrene‐co‐acrylonirile) (SAN)/multi‐walled carbon nanotubes (MWCNTs) composites was synthesized. It has been identified that naphthalene unit in backbone of compatibilizer interacts with MWCNTs via ππ interaction and that the PMMA graft of the compatibilizer is miscible with the SAN matrix. When a small amount of compatibilizer was added to SAN/MWCNT composites, MWCNTs were more homogeneously dispersed in SAN matrix than the case without compatibilizer, indicating that the compatibilizer improves the compatibility between SAN and MWCNTs. As a consequence, mechanical and electrical properties of the composites with compatibilizer were largely improved as compared with those of composites without compatibilizer. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 4184–4191, 2010

A Study of the Synthesis of EPDM-g-MAN and Toughness of its Blend with SAN (AEMS)

Ethylene–propylene–diene–methyl methacrylate/acrylonitrile terpolymers (EPDM-g-MAN) were synthesized by comonomers methyl methacrylate and acrylonitrile (MMA-AN) grafted on EPDM macromolecules with solution graft copolymerization. The engineering plastics of the blend of EPDM-g-MAN with SAN (AEMS) were prepared by blending EPDM-g-MAN with SAN resin. The effect of AN/MMA-AN weight percentage (f AN) on monomer conversion ratio, grafting ratio, and grafting efficiency of the graft copolymerization and the notched Izod impact strength of AEMS were investigated. The notched Izod impact strength of AEMS, prepared by blending SAN with EPDM-g-MAN, was synthesized under our optimum S2 reaction conditions, with EPDM/MMA-AN weight proportion of 50/50 and f AN of 10 wt%, presenting a peak with the maximum value of 61.0 kJ/m2. The microstructure of AEMS prepared with S2 reaction conditions showed that when the polarity of EPDM-g-MAN was appropriate, the EPDM phase formed a pseudocontinuous phase in the SAN matrix and the interfacial adhesion was strong, which could induce shear yielding of the SAN matrix. Differential scanning calorimetry analysis showed that there was good compatibility between SAN resin and EPDM-g-MAN synthesized with f AN of 10 wt% and a EPDM/MMA-AN weight ratio of 50/50.

Deformation of dispersed PA66 phase in drawn PA66/SAN blend

Polyamide 66/styrene acrylonitrile (PA66/SAN) drawn strands were prepared by stretching the corresponding extrudates at 130 °C. During stretching, the PA66 droplets in the extrudate are deformed as a result of the stretching-induced stress. In drawn strands, the morphology of the deformed PA66 is greatly affected by the morphology of the PA66 dispersed phase in the extrudate as well as by the interfacial adhesion between the PA66 and SAN matrix. Upon stretching, the cylindrical PA66 threads in the uncompatibilized extrudate [styrene acrylonitrile maleic anhydride (SANMA) as compatibilizer] deform into PA66 fibrils with large aspect ratio, while the small spherical PA66 droplets are only slightly deformed. Interfacial adhesion between the PA66 and SAN is improved in the compatibilized PA66/SAN extrudate. Consequently, despite the small diameter, PA66 droplets in the compatibilized blend are greatly deformed during stretching.

Effect of a dodecylsulfate‐modified magnesium–aluminum layered double hydroxide on the morphology and fracture of polystyrene and poly(styrene‐co‐acrylonitrile) composites

AbstractComposites of polystyrene (PS) and poly(styrene‐co‐acrylonitrile) (SAN) containing a fraction of a dodecylsulfate‐modified Mg–Al layered double hydroxide (LDH) were prepared by means of a melt‐extrusion process. The structure and morphology were analyzed with wide‐angle X‐ray scattering and transmission electron microscopy, respectively. The X‐ray spectra of the PS matrix composite displayed the diffraction peak characteristic of the hybrid LDH basal plane at 2θ = 3.1 deg. The SAN matrix composite did not exhibit such a diffraction peak. Both PS and SAN composites displayed an intercalated type of morphology with respect to the LDH platelets, as assessed by transmission electron microscopy. A plasticizing effect due to the hybrid LDH particles was observed for all composites and was supported by a decrease in the glass‐transition temperature values and by Fourier transform infrared spectra. Besides tensile properties, the fracture toughness of the composites was compared with that of the pure polymers through the linear elastic fracture mechanics parameters. They were determined from fracture tests under a three‐point‐bending configuration. The results indicated that the effect of adding a small fraction of modified LDH particles to SAN caused an improvement in fracture toughness of 50% with respect to that of the pure polymer. Moreover, the relative increase in the fracture energy was about 200%. For PS matrix composites, both tensile properties and linear elastic fracture mechanics fracture parameters remained unaffected. These results were explained on the basis of the different plasticities developed by both polymers around the particles. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Reactive Blending of Polyamide 6 and Styrene−Acrylonitrile Copolymer: Influence of Blend Composition and Compatibilizer Concentration on Morphology and Rheology

In this article, we report on the influence of reactive compatibilization on the morphological and rheological properties of blends of polyamide 6 (PA 6) and a styrene−acrylonitrile copolymer (SAN). PA 6/SAN blends with two different composition ratios (70/30 and 30/70) and varying concentration of a styrene acrylonitrile maleic anhydride terpolymer (SANMA) were prepared. During melt mixing, the amino end groups of PA 6 react with the maleic anhydride groups of SANMA. The objective of this work is to study the elastic and viscous properties of the blends in shear and elongation as a function of compatibilizer concentration. The composition ratio of the blends (PA 6 or SAN matrix) has a strong influence on the morphology and rheology of the blends, in particular for large SANMA concentrations. We explain this phenomenon by the asymmetric properties of the reactively compatibilized interface which originates from the comblike architecture of the in situ generated interfacial agent. In linear viscoelastic sh...

Graft Reaction of Styrene-acrylonitrile onto Metallocene-Based Polyethylene-Octene Elastomer and its Toughening Effect on SAN

Metallocene-Based Polyethylene-Octene-graft-styrene/acrylonitrile (POE-g-SAN) was synthesized by grafting styrene (St) and acrylonitrile (An) onto POE elastomer. The reaction was carried out in toluene using benzoyl peroxide as initiator at 75 °C. Various weight ratios of monomers, weight ratios of POE to monomers, initiator concentration, reactant concentration, and reaction time were studied to investigate their effects on the graft copolymerization. The graft copolymer were identified and characterized by FT/IR spectroscopy and 1H NMR. The chain structure of the graft copolymer was investigated by glass transition temperature using differential scanning calorimetry (DSC). The results showed that St/An was grafted on the POE chains, and the graft branches effected the crystallization of POE chains and made the melt temperature and the fusion heat be lower. In addition, according to the research on mechanical properties of the SAN/POE-g-SAN blend, a remarkable toughening effect of POE-g-SAN on SAN resin was found. By means of scanning electron microscopy (SEM), the toughening mechanism is proposed to be crazing initiation from rubber particles and shear deformation of SAN matrix.

EPDM/St‐An graft copolymerization reaction behavior by phase inversion emulsion and the toughness effect of EPDM‐g‐SAN on SAN resin

AbstractStyrene‐EPDM‐acrylonitrile tripolymer (EPDM‐g‐SAN) was synthesized by the graft copolymerization of styrene (St) and acrylonitrile (An) onto ethylene‐propylene‐diene terpolymer (EPDM) with “phase inversion” emulsification technique. The high impact strength engineering plastics AES was the blend of SAN resin and EPDM‐g‐SAN, which occupied good weathering and yellow discoloration resistivity. The effects of An percentage in comonomer and the weight proportion of EPDM to St‐An on graft copolymerization behavior and AES notched impact strength were studied. The results showed that monomer conversion ratio (CR) exhibited a peak when the An percentage changed, and the maximum value was 97.5%. Grafting ratio (GR) and grafting efficiency (GE) enhance as well. The notched impact strength of AES presented a peak with the maximum value of 53.0 KJ/m2, when An percentage was at the range of 35–40%. The spectra of FTIR showed that St and An were graft onto the EPDM. DSC analysis illuminated that Tg of EPDM phase in the blends was lower than that of the pure EPDM. TEM and SEM micrographs indicated that the polarity of g‐SAN of EPDM‐g‐SAN was the main factor effect the particle morphology, in terms of size, distribution and isotropy. When weight ratio of St to An was 65/35, the polarity of g‐SAN chains was appropriate, and the EPDM‐g‐SAN particles dispersed well in the SAN matrix. The super impact toughness is interpreted in terms of EPDM phase cavitation and enhanced plastic shear yielding. The highest toughness occurs at an optimum EPDM‐g‐SAN phase particle size which is about 0.2 μm in SAN resin matrix. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Influence of Molecular Weight of SAN on Rheological and Mechanical Properties of ABS-plastics

Abstract Rheological and mechanical properties of acrylonitrile-butadiene-styrene polymers (ABS) prepared via bulk polymerization depending on the molecular weight (Mw) of styrene-acrylonitrile copolymer (SAN) have been investigated. The tendencies of attaining the yield stress at steady-state shear flow and approaching to the “plateau” region of storage modulus at low frequencies in oscillatory tests were observed. Both these phenomena are induced by formation of the structural skeleton consisting of polybutadiene (PB) particles arranged in the SAN-matrix. Growth of Mw of SAN leads both to increase of the “plateau” value of storage modulus at low frequencies and the yield stress. This fact can be explained by the influence of Mw of SAN chains grafted onto PB particles on structure formation in ABS melts because of a redistribution of the ratio particle-particle / particle-matrix interactions. The elongational viscosity of ABS melts is a power function of Mw of SAN matrix. The power index of this function increases with the polymer straining that reflects orientation of SAN chains with their length increase. The strain-hardening index of ABS melts increases considerably with increase of SAN matrix Mw. However, it does not depend on presence of PB particles in the material. It means that the value of this index is governed by orientation effect in the SAN matrix. The impact strength of the investigated ABS samples is interrelated with rheological characteristics of ABS melts as well as Mw of SAN. The dependence of impact strength on Mw can be explained by increasing role of orientation effects of SAN chains with Mw increase in the copolymer fibrils connecting the walls of crazes formed at impact action.

Morphology, Thermal and Mechanical Properties of Poly (Styrene-Acrylonitrile) (SAN)/Clay Nanocomposites from Organic-Modified Montmorillonite

Poly (styrene-acrylonitrile) (SAN)/clay nanocomposites have successfully been prepared by melt intercalation method. The hexadecyl triphenyl phosphonium bromide (P16) and cetyl pyridium chloride (CPC) are used to modify the montmorillonite (MMT). The structure and thermal stability property of the organic modified MMT are, respectively characterized by Fourier transfer infrared (FT-IR) spectra, X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The results indicate that the cationic surfactants intercalate into the gallery of MMT and the organic-modified MMT by P16 and CPC has higher thermal stability than hexadecyl trimethyl ammonium bromide (C16) modified MMT. The influences of the different organic modified MMT on the structure and properties of the SAN/clay nanocomposites are investigated by XRD, transmission electronic microscopy (TEM), high-resolution electron microscopy (HREM), TGA and dynamic mechanical analysis (DMA), respectively. The results indicate that the SAN cannot intercalate into the interlayers of the pristine MMT and results in microcomposites. However, the dispersion of the organic-modified MMT in the SAN is rather facile and the SAN nanocomposites reveal an intermediate morphology, an intercalated structure with some exfoliation and the presence of small tactoids. The thermal stability and the char residue at 700°C of the SAN/clay nanocomposites have remarkably enhancements compared with pure SAN. DMA measurements show that the silicate clays improve the storage modulus and glass transition temperature (Tg) of the SAN matrix in the nanocomposites.

Synthesis of Polythiophene-graft-PMMA and Its Role as Compatibilizer for Poly(styrene-co-acrylonitrile)/MWCNT Nanocomposites

A new compatibilizer, polythiophene-graft-poly(methyl methacrylate) (PMMA), for poly(styrene-co-acrylonitrile) (SAN)/multiwalled carbon nanotube (MWCNT) composite is synthesized. Fluorescence emission spectra and Raman spectra indicate that the polythiophene part of the compatibilizer strongly interacts with the surface of MWCNT, while differential scanning calorimeter (DSC) thermograms show that the PMMA graft of the compatibilizer is miscible with the SAN matrix. The use of new compatibilizer yields well-dispersed SAN/MWCNT nanocomposites with enhanced mechanical properties, whereas the simple mixture of SAN/MWCNT prepared without the addition of the compatibilizer shows an aggregation of MWCNT in SAN matrix. Particularly, SAN/MWCNT nanocomposites in the presence of the compatibilizer show dramatically improved mechanical properties even with the addition of a very small amount (0.01 wt %) of MWCNT.

Preparation and characterization of poly (styrene-acrylonitrile) (SAN)/clay nanocomposites by melt intercalation

Poly (styrene-acrylonitrile) (SAN)/clay nanocomposites have been prepared by melt intercalation method from pristine montmorillonite (MMT), using hexadecyl trimethyl ammonium bromide (C16) and hexadecyl triphenyl phosphonium bromide (P16) as the reactive compatibilizers between polymer and clay. The influence of the reactive compatibilizers proportion relative to the clay on the structure and properties of the SAN/clay nanocomposites is investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM), high-resolution electron microscopy (HREM), thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The effects of the two different clays (MMT and organic modified MMT) on the nanocomposites formation, morphology and property are also studied. The results indicate that the SAN cannot intercalate into the interlayers of the MMT and results in microcomposites. In the presence of the reactive compatibilizers, the dispersion of clay in SAN is rather facile and the SAN/clay nanocomposites reveal an intermediate morphology, an intercalated structure with some exfoliation and the presence of small tactoids. The appropriate proportion with 3 wt% reactive compatibilizers to 5 wt% MMT induces well-dispersed morphology and properties in the SAN matrix. The TGA analyses show that the thermal stability properties of the SAN/clay nanocomposites have been improved compared with those of the pristine SAN. The DMA results show that the storage modulus and glass transition temperature (Tg) of the SAN/clay nanocomposites have remarkably enhancements compared with the pristine SAN. At last the intercalation mechanism of the technology is discussed.

Structure–properties relationship in toughening of poly(butylene terephthalate) with core–shell modifier

AbstractThe performance of acrylonitrile–butadiene–styrene (ABS) core–shell modifier with different grafting degree, acrylonitrile (AN) content, and core–shell ratio in toughening of poly(butylene terephthalate) (PBT) matrix was investigated. Results show PBT/ABS blends fracture in ductile mode when the grafting degree is high, and with the decrease of grafting degree PBT/ABS blends fracture in a brittle way. The surface of rubber particles cannot be covered perfectly for ABS with low grafting degree and agglomeration will take place; on the other hand, the entanglement density between SAN and PBT matrix decreases because of the low grafting degree, inducing poor interfacial adhesion. The compatibility between PBT and ABS results from the strong interaction between PBT and SAN copolymer and the interaction is influenced by AN content. Results show ABS cannot disperse in PBT matrix uniformly when AN content is zero and PBT/ABS fractures in a brittle way. With the addition of AN in ABS, PBT/ABS blends fracture in ductile mode. The core–shell ratio of ABS copolymers has important effect on PBT/ABS blends. When the core–shell ratio is higher than 60/40 or lower than 50/50, agglomeration or cocontinuous structure occurs and PBT/ABS blends display lower impact strength. © 2006 Wiley Periodicals, Inc. J Appl PolymSci 102: 5363–5371, 2006

Effect of dissolution-based recycling on the degradation and the mechanical properties of acrylonitrile–butadiene–styrene copolymer

A dissolution-based recycling technique for acrylonitrile–butadiene–styrene copolymer (ABS) is proposed, and the effects of repeated recycling cycles are studied measuring changes in chemical structure, melt viscosity, and tensile and impact properties. Acetone as solvent, 0.25 g/ml concentration, room temperature and 40 min for dissolution have been found to be the most reliable recycling parameters. FTIR, DSC and MFI results have shown that the dissolution-based recycling itself does not degrade the ABS. However, TGA analysis suggests that during the dissolution some stabilizers are probably eliminated, and consequently degradation takes place in the following injection moulding step. Darkening of recycled ABS is attributed to the butadiene degradation, pointed out by FTIR results. Otherwise, the chemical structure of the SAN matrix has not been modified, but its molecular weight has been reduced. The modulus of elasticity is not affected even after four recycling cycles. However, yield stress and impact strength decrease after the first recycling cycle, and remain constant in the following steps.