Styrene Content Research Articles

INFLUENCES OF THE COMPATIBILITY OF NR/SSBR AND PHASE-SELECTIVE DISTRIBUTION OF SILICA ON ITS STATIC AND DYNAMIC PROPERTIES

ABSTRACT The compatibility between solution polymerized styrene–butadiene rubber (SSBR 2466) and natural rubber (NR) is characterized by differential scanning calorimetry and dynamic mechanical thermal analysis. The single glass transition in the entire temperature range of all NR/SSBR blends and good correlation between Tg and SSBR fraction prove the excellent compatibility between SSBR 2466 and NR. With increasing SSBR content, a reduced Payne effect, more homogeneous dispersion of silica, stronger rubber–filler interaction, and more silica selectively distributed in the SSBR phase were determined via rubber-processing analysis, transmission electron microscopy, bound rubber, and thermogravimetric analysis, respectively. The high vinyl content, low styrene content, and end-functionalized structure of SSBR play vital roles in promoting its compatibility with NR and a stronger rubber–silica linkage. The resulting increased tan δ at 0 °C and low tan δ at 60 °C indicates good wet-skid resistance and low rolling resistance by blending SSBR 2466, and 70/30 NR/SSBR is the best balance for producing a “green tire” tread.

Morphological, mechanical, and thermal properties of PP/SEBS/talc composites

The aim of this study is to evaluate the effect of some experimental variables such as the content of styrene–ethylene–butylene–styrene (SEBS) and talc, processing conditions and mixing protocol on the properties of polypropylene (PP). To achieve this objective, PP/SEBS blends and PP/SEBS/talc composites were processed in a corotating twin-screw extruder. A masterbatch of PP/talc was prepared before the extrusion of PP/SEBS/talc composites. The morphology of blends and composites was evaluated by scanning electron microscopy, which revealed the dispersion of small rubber droplets in the PP matrix. Moreover, the micrographs also showed that SEBS and talc particles were uniformly dispersed and distributed in the polymer matrix. Results of thermal properties showed that talc had a nucleating effect, which promoted the increase of both PP crystallization temperature and crystallinity degree. The incorporation of talc in PP/SEBS blends led to an expressive increase in the impact resistance by 70% as compared with the reference blend: PP/SEBS 80/20% (w/w). This result reveals that although the PP/SEBS/talc composites showed a separated morphology, the good dispersion and distribution of this mineral filler in the polymers contributed to avoid crack propagation and increase the impact properties. The tensile properties in the elastic region were not significantly affected.

Synthesis of alcoholate of sodium aliphatic aminoalcohols

At present, the development of modern materials science in the field of development and synthesis of new functional materials for use in various industries is impossible without providing a set of initial compounds of a given composition. Introduction to the composition of organic compounds of metals expanded the synthetic possibilities of organic chemistry. It is known that the catalysts, the polymerization unioneu you can use metallicity, alkoxides (alcoholates), and amides of metals. Currently, with the use of n-butylithium, industrial processes of obtaining SKD-L polybutadiene have been implemented.the Main purpose of this work was to obtain Ethylenediamine-N,N’-sodium diisopropylate and study it as a modifying additive to the initiating system for the production of statistical butadiene-styrene rubber. At the initial stage, it was important to synthesize hydroxypropylated Ethylenediamine, to determine the optimal process conditions, to analyze the composition of products, to establish the optimal ratio of the initial products corresponding to the highest yield of the hydroxypropylated product containing secondary amine groups. The work synthesized alcohol interaction oxypropylation of Ethylenediamine with sodium metal. It was found that the synthesized product exhibits the properties of a modifying additive to the initiating system of styrene-butadiene copolymerization. Butadiene-styrene rubber, obtained on the basis of Ethylenediamine-N, n’-sodium diisopropylate, is strictly statistical and is characterized by an average to a predominant content of 1.2 links in the butadiene part, low content of microblock styrene in the main part of the carbon chain.

Copolymerization of Norbornene and Styrene with Anilinonaphthoquinone-Ligated Nickel Complexes.

Poly(norbornene-co-styrene)s were synthesized by the use of anilinonaphthoquinone-ligated nickel complexes [Ni(C10H5O2NAr)(Ph)(PPh3): 1a, Ar = C6H3-2,6-iPr; 1b, Ar = C6H2-2,4,6-Me; 1c, Ar = C6H5] activated with modified methylaluminoxane (MMAO) or B(C6F5)3 in toluene. The effects of the cocatalysts were more significant than those of the nickel complexes, and MMAO gave higher activity than B(C6F5)3. The structural characterizations of the products indicated the formation of statistical norbornene copolymers. An increase of the styrene ratio in feed led to an increase in the incorporated styrene (S) content of the resulting copolymer. The molecular weight of the copolymer decreased with increasing the S ratio in feed at 70 °C. The copolymerization activity, using MMAO as a cocatalyst, decreased with lowering of the temperature from 70 to 0 °C, accompanied by an increase in the molecular weight of the copolymer. The S incorporation up to 59% with Mn of 78,000 was achieved by the 1b-B(C6F5)3 catalytic system. The glass transition temperatures of the norbornene (N)/S copolymers determined by differential scanning calorimetry, decreased from 329 to 128 °C according to the S content.

Synthesis and thermal properties of a triblock copolymer for lithium metal polymer batteries

PEO-based polymer electrolytes usually show a high degree of crystallinity, leading to a drop of ionic conductivity, at temperatures below their melting point [1]. However, the incorporation of foreign units in the polymer chains, forming a copolymer, can reduce the crystallinity while keeping the conductivity high if the units are properly chosen. In this study, a series of poly(styrene-co-styrene trifluoromethanesulfonylimide of potassium)-b-poly(ethylene oxide)-b-poly(styrene-co-styrene trifluoromethanesulfonylimide of potassium) (P(S-co-KSTFSI)-b-PEO-b-P(S-co-KSTFSI)) BAB triblock copolymers was synthesized by reversible addition-fragmentation chain transfer polymerization (RAFT) in a dispersed medium. It was found that the copolymers, with or without styrene, containing 59% (wt%) or more PEO, are semi-crystalline while, below this value, they are amorphous. However a low PEO content can be compensated by a low KSTFSI/PEO ratio for the BAB copolymers with styrene since materials containing only between 53 and 58% (wt%) PEO can still crystallize for a KSTFSI/PEO ratio of about 40/100. For the copolymers that crystallize, with or without styrene, the degree of crystallinity decreases with a reduction of the PEO content. In the case of a constant PEO content, the degree of crystallinity increases with the styrene content (and with the decrease of the KSTFSI/PEO ratio). In all cases, only one Tg is observed, the only difference is the width, which is larger for the copolymers than the corresponding homopolymers.

Synthesis, characterization, rheological and self-assembly behavior of polyelectrolytes hydrophobically modified with high styrene content: Effect of external parameters on thickening properties and nano-associations

Acrylamide (AM)/2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS)/styrene (St) (AMAS) and AM/sodium styrenesulfonate (SSS)/St (AMSS) polyelectrolytes were synthesized by micellar copolymerization method and then characterized using 1H-NMR, rheometry, viscometry, dynamic light scattering (DLS) and water solubility analyses. It was found that polyelectrolytes are not soluble in the water due to their high length of St blocks (NH=15.4); however, a significant self-assembly behavior of St nano-sized associations was observed by adding a low amount of SDS (10 mM) to the aqueous solution, resulting in the improved rheological behavior of the corresponding solutions. Effect of the external stimuli including emulsifier (SDS) and electrolyte (NaCl) concentration and temperature on the reduced viscosity of polyelectrolyte solutions was also studied using I-optimal design. Based on the viscosity measurements, notable thickening ability for aqueous solutions of both the AMAS and AMSS samples were observed at a SDS concentration of 6.5 mM, NaCl concentration of 0.55 wt% and temperature of 25 °C, which was further confirmed using oscillatory frequency sweep and dynamic light scattering measurements. Moreover, the higher thickening ability was observed for the AMSS aqueous solution in comparison with the AMAS one.

Synthesis and Properties of In-Situ Bulk High Impact Polystyrene Toughened by High cis-1,4 Polybutadiene

A series of high impact polystyrenes (HIPS) were successfully prepared by in-situ bulk polymerization. Selective polymerization of butadiene (Bd) in styrene (St) was achieved by using a neodymium bis(2-ethylhexanol)phosphonate/diisobutyl aluminum hydride/diethylaluminum chloride (Nd(P507)3/Al(i-Bu)2H/AlEt2Cl) catalyst, affording a prepolymer with high cis-1,4 content of 96.6% and extremely low styrene content of 1.01%. The prepolymer solution was further subjected to the radical polymerization of styrene to produce HIPS. The impact strength of HIPS increased from 48.5 to 166.2 J/m, with an increase of rubber content from 5% to 15%, whereas the tensile strength at break decreased from 17 to 12.5 MPa. Moreover, the impact strength and the tensile strength at break of HIPS increased from 72.4 J/m to 120.6 J/m and 13.2 to 16 MPa, respectively, as the initiator concentration decreased from 0.05% to 0.01%. HIPS showed the highest impact strength of 84.8 J·m−1 and displayed well “salami” morphology when using a trifunctional 3,6,9-triethyl-3,6,9-trimethyl-1,4,7-triperoxonane initiator.

Investigation of rheological behaviors of polyolefin blend type thermoplastic elastomers for quantifying microstructure-property relationships

Polyolefin blend type thermoplastic elastomers (TPEs) were prepared via melt blending method in a twin screw extruder by using isotactic polypropylene (i-PP), three different styrene-olefin triblock copolymers (SEBS-1 and SEBS-2 having a styrene content of 30 wt.% and 60 wt.%, respectively and SEEPS having a styrene content of 30 wt.%) and paraffinic oil. Composition-dependent and time-dependent viscoelastic properties of compounds were determined by various test procedures conducted in a rotational rheometer in melt state. It was found that the content of polystyrene blocks (or hard segment) in copolymers governed the rheological behaviors of compounds. It can be concluded that the increasing amount of styrene-olefin block copolymer or content of glassy domains into blend composition reduces miscibility between polyolefin and elastomer phases and also yields higher melt elasticity and viscosity, longer relaxation times, lower creep strain and compliance values at relatively longer time scale.

Preparation and characterisation of ion-conductive unsaturated polyester resins for the on-site production of resistivity sensors

Ion-conductive unsaturated polyesters were synthesised from poly(ethylene oxide) and maleic anhydride for use in the development of improved methods for the structural health monitoring of infrastructural buildings. The unsaturated polyesters (UPs) were cross-linked with styrene using a redox initiator in the presence of LiClO4. Electrochemical impedance spectroscopy was used to study the effects of initiator and styrene concentration as well as the EO:Li+ ratio. Increasing the initiator or styrene content results in an increased resistivity of the final materials. Cross-linking with styrene does not appear to cause microphase separation into pure UP and polystyrene phases, since the resulting resistivities are significantly lower than predicted by the rule of mixtures. For all temperatures under investigation (0 to 60 °C), the lowest resistivities were found for a EO:Li+ ratio of 50 (400 Ω m at 22 °C), which is in accordance with previous findings. The electrical properties of the present materials are determined by diffusion-controlled process in such a way polarisation prevails at high temperatures. In a proof of principle experiment, one selected UP formulation was injected into drill holes in concrete and cured at different temperatures and moisture conditions. This system reliably monitors the resistivity against an embedded reference electrode.

Scalable preparation of alternating block copolymer particles with inverse bicontinuous mesophases

Block copolymer particles with controlled morphologies are of great significance in nanomaterials and nanotechnology. However, ordered inverse morphologies are difficult to achieve due to complex mechanism and formation conditions. Here we report scalable preparation of amphiphilic alternating block copolymer particles with inverse bicontinuous mesophases via polymerization-induced self-assembly (PISA). Concentrated dispersion copolymerizations (up to 40% solid content) of styrene (St) and pentafluorostyrene (PFS) employing a short poly(N,N-dimethylacrylamide) (PDMA29) stabilizer block lead to the formation of well-defined, highly asymmetric PDMA29-b-P(St-alt-PFS)x block copolymers with precise compositions and various morphologies, from simple spheres to ordered inverse cubosome mesophases. The particle morphology is affected by the molecular weight, solid content, and nature of the cosolvents. The cubosome structure is confirmed by electron microscopies and small angle X-ray scattering spectroscopy. This scalable PISA approach offers facile access to ordered inverse mesophases, significantly expanding the PISA morphology scope and enabling its applicability to the materials science fields.

Evaluation of pH- responsive poly(styrene-co-maleic acid) copolymer nanoparticles for the encapsulation and pH- dependent release of ketoprofen and tocopherol model drugs

The pH- induced intelligent drug release ability of poly(styrene-co-maleic acid) copolymer nanoparticles (SMA NPs; d = 22.4 ± 3.1 nm) is presented using poorly water soluble ketoprofen (KETO) and α-Tocopherol (TP) model drugs. Increasing styrene content of the copolymer led to lower surface charge (from −28.4 to −15.0 meq/100 g) and the different styrene/maleic acid ratio (SMA#1: 1:2; SMA#2: 2:1 and SMA#3: 3:1) influences the pH- dependent solubility properties. Because of the polyanionic nature, homogeneous polymer solution was obtained at higher pH, while at lower pH nanoparticles were formed. The corresponding cut- off pH values showed increasing tendency with increasing hydrophobicity (pH = 3.12, 4.22 and 5.44 for SMA#1, 2 and 3, respectively).Next the hydrophobic, non- water soluble KETO and TP drug cores were coated with SMA#2 shell. The polymer-stabilized drug particles provided stable dispersion in aqueous environment, i.e. the prepared polymer shell increased the water dispersibility of the initial hydrophobic drugs. According to the experiments the release of low crystallinity KETO drug was almost complete at physiological pH (=7.40), while at acidic pH the released amount of model drug was only about 30%. Similar kinetic release profile was obtained in the case of more hydrophobic TP drug without charged groups and it indicates that the drug release was primarily controlled by the pH- responsive polymer particles instead of the pH- dependent solubility of the model drug. The prepared NPs could be useful in all areas where the alkaline pH value causes problems, for example in the case of female genital diseases of fungal origin.

ОСАДОВА КОПОЛІМЕРИЗАЦІЯ 4-ВІНІЛПІРИДИНУ ЗІ СТИРОЛОМ

The determination of the copolymers of 4-vinylpyridine with styrene copolymers real composition, formed under the conditions of precipitation copolymerization in CCl4, is described. For this, 4-vinylpyridine with styrene was copolymerized in different ratios. The composition of the obtained copolymers was determined according to 1H NMR spectroscopy. A comparison of the real copolymers composition with the theoretically calculated ones was performed as well. The copolymerization of styrene with 4-vinylpyridine was carried out in sealed ampoules in argon medium. Solutions of a concentration of 1.02 mol/l in CCl4 were prepared. The initiator azobisisobutyronitrile in the amount of 0.00106 mol/l was added. The copolymerization was carried out in a thermostat C1823 at T = 75 ± 0.5°C. The copolymerization time was 3 hours. The original ratio of monomers (4-vinylpyridine:styrene) = 6:1; 5:1; 4:1; 3:1; 2:1; 1:2; 1:3; 1:4; 1:5; 1:6. The composition of the obtained copolymers was determined according to 1H NMR spectroscopy. It was determined that copolymers of 4-vinylpyridine with styrene obtained by precipitation copolymerization in CCl4 were enriched by 4-vinylpyridine bonds. On the contrary, the calculation of the instant composition of the copolymers according to the literature shows that under the conditions of classical copolymerization in 4-vinylpyridine solution is less active than styrene. We calculated the theoretical relative constants of copolymerization of styrene with 4-vinylpyridine: r1 = 1.97; r2 = 0.93. Therefore, under the conditions of classical copolymerization in solution 4-vinylpyridine is less active than styrene (r2 < r1). It was also found out that for the original molar content of styrene if it is greater than 0,85, it is not possible to synthesize by means of precipitation polymerization into CCl4 the copolymers of 4-vinylpyridine:styrene.

Imidazolium-Based Anion Exchange Membranes for Alkaline Anion Fuel Cells: Interplay between Morphology and Anion Transport Behavior

We studied anion transport behaviors in grafted anion exchange membranes (AEMs) composed of 2-methyl-N-vinylimidazole (Im) and styrene (St) having various Im/St ratios (6/4, 4/6, and 3/7) grafted onto poly(ethylene-co-tetrafluoroethylene) films (named AEM64, AEM46, and AEM37). The transport properties were evaluated based on the transport efficiency defined as ratios of anion diffusion coefficients in AEMs to dilution solutions (D/D0) and were correlated to the morphology of AEMs analyzed by the small angle scattering method. We found a master curve of D/D0 with hydration for AEM64, regardless of the grafting degree and anion species; however, D/D0 for AEM46 and AEM37 was similar with AEM64 at low hydration conditions, but clearly deviated down from it at high hydration conditions. Such difference could be elucidated by the membrane morphology. For AEM64, the conducting phase was homogeneous comprised dispersed ions, and the conductivity correlated well with the increasing hydration. In contrast, when the styrene content increased (i.e., AEM46 and AEM37), the conducting phase changed to heterogeneous with water puddles separated from dispersed ions, and the anion transport was suppressed. Results in this work gave a mechanistic insight in the anion transport properties in proximity of the AEM morphology at various hydration conditions.

Energy migration effect on the formation mechanism of different unsaturations in ethylene/styrene random copolymers

To evaluate the influence of specific parameters, i.e. energy sink concentration and excitons and/or radical migration, on the mechanisms underlying the formation of double bonds in aliphatic polymers, materials with energy sinks in the chain were synthesized. By following the radiation-induced modifications in ethylene/styrene random copolymers, as a function of the styrene content and of the irradiation temperature, we were able to understand the formation mechanisms of trans-vinylenes, trans-trans-dienes, allyl radicals and vinyls. The irradiation temperature allows the discrimination between energy transfers (at 11 K and at room temperature, RT) and of radical migration (at RT). Irradiations were performed using swift heavy ions, and we could show that track overlapping has also an influence on the studied chemical group concentrations. For instance, trans-vinylenes are influenced by excitation transfer and radical migration: their formation decreases in presence of styrene aromatic rings, whatever the dose range and the irradiation temperature. On the opposite, vinyls are formed only at high ionizing density and are not influenced by excitation transfer; however, their concentration is influenced by radical migration.

C–C bridged Ni(II) complexes bearing β‐keto‐9‐fluorenyliminato ligands prepared by different in situ bonding mechanisms and their use in catalytic (co)polymerization of norbornene and styrene

Two C–C bridged Ni(II) complexes bearing β‐keto‐9‐fluorenyliminato ligands with electron‐withdrawing groups (─CF3), Ni{PhC(O)CHC[N(9‐fluorenyl)]CF2}2 (Ni1) and Ni{CF3C(O)CHC[N(9‐fluorenyl)]Ph}2 (Ni2), were synthesized by metal coordination reaction and different in situ bonding mechanisms. The C–C bridged bonds of Ni1 were formed by in situ intramolecular trifluoromethyl and 9‐fluorenyl carbon–carbon cross‐coupling reaction and those of Ni2 were formed by in situ intramolecular 9‐fluorenyl carbon–carbon radical coupling reaction mechanism. The obtained complexes were characterized using 1H NMR spectroscopy and elemental analyses. The crystal and molecular structures of Ni1 and Ni2 with C–C bridged configuration were determined using X‐ray diffraction. Ni1 and Ni2 were used as catalysts for norbornene (NB) polymerization after activation with B(C6F5)3 and the catalytic activities reached 106 gpolymer molNi−1 h−1. The copolymerization of NB and styrene catalyzed by the Ni1/B(C6F5)3 system showed high activity (105 gpolymer molNi−1 h−1) and the catalytic activities decreased with increasing feed content of styrene. All vinyl‐type copolymers exhibited high molecular weight (104 g mol−1), narrow molecular weight distribution (Mw/Mn = 1.71–2.80), high styrene insertion ratios (11.13–50.81%) and high thermal stability (Td > 380°C) and could be made into thin films with high transparency in the visible region (400–800 nm).

Effect of core-shell structure latex on pigment coating properties

The pore structure of the coating layer is one of the most important factors in determining the printability of coated papers. The coating pigment and binder are two principal components in paper coating, and their characteristics have a critical influence on the coating structure. The glass transition temperature (Tg) of latex binders affects the mechanical strength and pore structure of the pigment coating layer because the latex Tg influences the binding ability of latex and the shrinkage of the coating layer during the drying process. In this study, styrene-acrylate (S/A) core-shell structure latexes with different monomer compositions in the core and shell layers were designed, and their properties were compared with those of a conventional latex. These core-shell latexes were prepared using the same monomers in the same proportion and were used to investigate the effect of the core-shell structure on the structural and mechanical properties of the coating layer. The hard-shell latex with a high styrene content in the shell part yielded paper that was glossier and less rough and formed finer pores, resulting in an increased ink absorption rate into the coated paper compared to the other types of latex. The hard-shell structure showed better performance in printing uniformity and had less mottling.

An alternative and indirect statistical modeling method for viscosity estimation and its experimental validation for low styrene content polyester resin

Abstract We propose an indirect method of ASTM D-1200 for measurement of viscosity from 0.1 to 30 stokes (St) using Ford cup 5 (range 2~ 12 St) by developing a statistical relation. General purpose low styrene content polyester resin (without adding initiator, hardener and accelerator) was used for viscosity measurement. In existing ASTM D 1200 standard, ford cups (1-4) are used to measure the viscosity up to 2 St, while fifth cup is used for measurement from 2 to 12 St. Viscosity above 12 St is not estimated using existing ASTM D- 1200 method. In contrast, our method and statistical relation proposed in this paper estimates viscosity in the flexible range of 0.1 to 30 St by using Ford cup 5 only. The estimated values were confirmed by existing ASTM D-1200 (0.1 to 12 St) and by using Ubbelohde viscometer (12 to 30 St). Values estimated above 12 St are from the proposed model are also in good conformance (percentage error ~ 5% or less) with experimental results. The satisfaction level of the estimated values with the experiments suggests that the model has also the potential for application to paints, polymer and oil industry.

Synthesis and Properties of Poly(Propylene Glycol Maleate Phthalate)–Styrene Copolymers as a Base of Composite Materials

Comparative analysis of the physicochemical properties of styrene solutions of poly(propylene glycol maleate phthalate) with different initial reactant ratio was performed. Increased content of phthalic anhydride in the initial monomer mixture in the synthesis of the unsaturated polyester leads to worse properties of the ready product, poly(propylene glycol maleate phthalate)–styrene copolymer prepared by cold curing. Solutions of poly(propylene glycol maleate phthalate) in styrene with ~30 wt % styrene content exhibit the highest viscosity, allowing the use of the cured product as a structural composite material. The solutions containing ~40 wt % styrene have lower viscosity and are suitable for preparing less hard plastics for general purposes.

Core-Shell Morphology of Redispersible Powders in Polymer-Cement Waterproof Mortars.

Redispersible powders based on soft core-hard shell polymer particles can be used as additives in polymer-cement mortars. The role of this morphology on the spray-drying production of these powders and on the crack-bridging properties of the corresponding cement-based membranes is investigated. Different polymer latexes at high solid content with varied core-shell ratio, shell thickness and chemical composition (hardness) were prepared from styrene and 2-ethylhexyl acrylate monomers via semi-batch emulsion polymerization. The latexes were characterized in terms of size, composition, and glass transition temperature (T), and spray-dried to obtain redispersible polymer powders (RPPs) using poly (vinyl alcohol) and limestone powder as anti-caking agents. The polymer powders were mixed with a mortar mixture and redispersed in water to produce cement-based membranes, which were tested for crack-bridging properties at different temperatures. The results showed that it was not possible to spray-dry a dispersion of homogeneous polymer particles with T of −25 C, unless these particles are protected by much harder (high T) shell. In particular, it was observed that a thicker shell improved the spray-ability, but lowered the crack-bridging properties of the produced membrane. A trade-off between these two was revealed to be the key for the optimal design of the polymer nanoparticles, as proven by the systematic study of the core-shell morphology reported in this work. The best compromise was shown to consist of particles larger than 300 nm, shell thickness of about 5 nm, and core-shell ratio of 97%, with styrene content in the shell not larger than 80% to avoid excessive hydrophobicity.

Distribution and modeling of tar compounds produced during downdraft gasification of municipal solid waste

Tar compounds produced during gasification of municipal solid waste (MSW) hinder downstream utilization of syngas. This study investigated the effects of operating conditions (temperature, equivalence air ratio (ER) and MSW moisture content) during gasification using air on tar emissions. Tar was quantified by gravimetric and GC-MS methods, denoted as gravimetric and collected (GC-MS) tar, respectively. Additionally, styrene evolution was studied as it is one of the main tar compounds produced from MSW. By applying the response surface methodology for modeling, it was found that tar contents quantified by the two methods are influenced similarly by ER and MSW moisture content, but differently by temperature. This discrepancy was attributed to the different composition and properties of tar fractions measured by gravimetric and GC-MS methods. Since the selection of analytical method can have impact on the quantification of tar, adoption of different methods for the characterization of tar emissions from MSW gasifiers is essential in order to provide a holistic analysis of the tar evolution process. The content of styrene in collected (GC-MS) tar from MSW gasification was 13–29%. The lower contents of styrene were favored by operating temperature between 850 and 900 °C, higher ER and higher MSW moisture content.