Linear Low-density Polyethylene Research Articles

Synthesis of linear low-density polyethylene waxes through chain-walking benzocycloalkyl nickel-catalyzed ethylene polymerization

Polyethylene wax is a highly useful material, and its diverse topological structures may have a significant impact on its applications. In this study, we have devised and synthesized a series of unilateral benzocycloalkyl α-diimine nickel catalysts. These nickel catalysts exhibited very high activities (1.06 to 10.25 × 106 g mol-1·h-1) and yielded branched (37–97/1000 C) polyethylene waxes with low molecular weights (Mn = 0.49 to 2.01 kg mol-1) and variable molecular weight distributions (1.79–35.05) in ethylene polymerization. Polymerization conditions such as pressure and temperature and catalyst structure such as backbone and axial substituents have an important influence on the polymerization activity and the properties of the resulting polyethylene waxes. High-temperature NMR reveals that these branched polyethylenes primarily feature short-chain branches, such as the methyl group, and exhibit a topology resembling that of low-molecular-weight linear low-density polyethylene (LLDPE).

Enhancing polyethylene‐based nanocomposites through ethylene plasma polymerization of carbon nanotubes and sequential ultrasound dispersion with melt mixing method

AbstractThis study investigates the enhancement of linear low‐density polyethylene (LLDPE) nanocomposites with multiwalled carbon nanotubes (CNT) at concentrations of 1, 3, and 6% w/w. To improve the interfacial interaction between the CNT and the polymeric matrix, CNT were treated using ethylene cold plasma (P‐CNT) in a rotary reactor. The incorporation of CNT into the polymer was carried out by a melt mixing process (MMP) and a sequential ultrasound dispersion method followed by melt mixing (UDM‐MMP). The thermal stability of nanocomposites with 6% P‐CNT increased by 45°C compared to pristine LLDPE. Electrical conductivity reached 2.5 × 10−2 S/cm for nanocomposites with 6% CNT. The elastic modulus increased from 519.52 MPa (LLDPE) to 714.63 MPa (6% CNT) and 795.43 MPa (6% P‐CNT), which further improving to 731.42 MPa (6% CNT) and 841.27 MPa (6% P‐CNT) using UDM‐MMP. Additionally, yield stress rose from 16.35 MPa to 21.28 MPa (6% CNT) and 22.06 MPa (6% P‐CNT), reaching 21.47 MPa and 22.28 MPa with UDM‐MMP. Tensile strength increased from 21.31 MPa to 25.15 MPa (6% CNT) and 25.9 MPa (6% P‐CNT), achieving 26.82 MPa (6% P‐CNT) with UDM‐MMP. These results highlight a significant improvement in conductivity, rigidity, and mechanical strength, emphasizing their potential for advanced applications.

Coil Formation and Biomimetic Performance Characterization of Twisted Coiled Polymer Artificial Muscles

A biological muscle's force is nonlinearly constrained by its current state (force, length, and speed) and state history. To investigate if artificial muscles can mimic (i.e. biomimetic) the complete mechanical state spectrum of biological muscles, this study uses a novel method to characterize twisted coiled polymer actuators (TCPAs) mechanically. Thus, comprehensive and reproducible test procedures are established to verify artificial muscle biomimetics regarding stress, strain, and strain rate combinations intrinsic to biological muscle. A rheometer performs novel high‐precision mechanical characterization methods to comprehensively verify biomimetic performance. Sample twist level, torque, length, force, and temperature are controlled and measured during twist‐induced coiling, heatsetting/annealing, and mechanical testing. TCPAs are formed from linear low‐density polyethylene monofilament. Linear low‐density polyethylene (LLDPE) TCPAs generate larger stresses than biological muscle through the entire spectrum of strains—contracting more than 40%, exerting more than 0.3 MPa at rest length, and withstanding tension of 8 MPa without damage. Thus, the LLDPE TCPAs attain biological muscle performance statically, but additional tests are required to assess this dynamically. The mechanical performance of LLDPE TCPAs enables biomimetic actuation with an intelligent control and measurement system. Their high‐throughput textile manufacturability positions them for advanced biomechatronic applications—including prosthetics and exoskeletons.

Enhancing circular plastic waste management: Reducing GHG emissions and increasing economic value in Rayong province, Thailand

This study evaluates the greenhouse gas (GHG) emissions and economic value creation of plastic waste (PW) management in Rayong, Thailand, a city on the eastern Gulf Coast with a significant amount of generated and leaked PW. By analyzing current practices, and developing and evaluating improvement scenarios, the study explores strategies for reducing GHG and enhancing economic benefits across the PW management chain. Four primary routes with varying capacities handle approximately 5,445.55 tonnes of PW via source separation recycling (5.18 %), post-sorting recycling (9.30 %), energy recovery (54.86 %), and landfills or opened dump disposal (30.66 %). About 83.21 % of the 16 ± 6.9 % PW in municipal solid waste (MSW) is recyclable, primarily consisting of high-density polyethylene (HDPE), polypropylene (PP), low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), and polyethylene terephthalate (PET). The current management practice generates an economic benefit of approximately 1.68 million USD/yr or 310 USD/t of PW, compared to the proposed scenarios, which enhances recycling efficiency and reduces landfill and energy recovery waste, yielding 2.27–6.48 million USD/yr or 420.64–1200.33 USD/t of PW. The practice emits about 7,028.47 tCO2e annually, while improved source and post-sorting efficiencies reduce GHG emissions by 2.86–3.17 times or −2.83 to −2.42 tCO2e/t of PW or a total of over 13,078.60–15,268.44 tCO2e. Burning PW increases approximately 1.6 times or 11,841.36 tCO2e/yr. Enhancing recycling efficiency, particularly through source separation, is key to promoting more productive and valuable PW separation, increasing economic value and GHG mitigation by approximately 3.87 and 3.17 times, respectively. These findings provide valuable insights for local authorities and policymakers to develop strategic interventions and policies that align with the improved scenario by enhancing source separation and recycling. The results demonstrate that improving the efficiency of separation at the source is critical for transitioning from a linear PW management strategy to a circular economy, significantly reducing landfill waste and mitigating environmental threats.

A step to microplastic formation: Microcracking and associated surface transformations of recycled LDPE, LLDPE, HDPE, and PP plastics exposed to UV radiation

Plastics when exposed to UV radiation start to degrade via photooxidative aging including free radical formation, oxidation, chain scission and/or crosslinking reactions. These chemical changes can cause loss in mechanical strength, surface embrittlement, and eventually surface erosion. The eroded particles are microplastics (MPs), which have been identified as a potentially serious threat to the environment and its inhabitants. In general, photodegradation of virgin plastics has been studied extensively, but there is not much literature on the degradation of recycled plastics. The goal of the study was to investigate the changes caused by photodegradation in recycled plastics and assess the potential risks of MPs formation. And eventually, knowing the chemical and physical transformations occurring on the surface understand the mechanism behind surface microcracking, which is the first step of MPs formation. Pellets of five industrially recycled plastics (low-density polyethylene (rLDPE), linear low-density polyethylene (rLLDPE), high-density polyethylene (rHDPE), and two polypropylenes (rPP)) from different waste sources were analysed. UV irradiation was performed in an accelerated weathering chamber for milled (< 400 µm) plastic powder to ensure homogeneous changes throughout the sample. The properties were investigated by ATR-FTIR, HT-SEC, XPS and DSC. Formation of microcracks was studied on plastic pellets by SEM. The results showed that the degradation significantly differed between the recycled plastics, and the waste source was more important than the plastic type. rLDPE and one of the rPP samples showed a significant increase in carbonyl index as well as decrease in molar mass during the first 500 h of UV exposure. The other rPP and rHDPE samples showed first considerable signs of degradation only after 1000 h of UV exposure. Minor changes were observed for the rLLDPE sample during the whole test. The SEM revealed microcracking on the surface of all samples, which also had noticeable degradation identified by other methods. These recycled plastics can be considered the ones with the highest potential of MPs formation. From the chemical and physical transformations identified on the surface, the mechanism leading to microcracking, which is the first step in the formation of MPs, is proposed.

Water Absorption Effect on Tensile Properties of Linear Low-Density Polyethylene (LLDPE) Blend with Recycle Acrylonitrile Butadiene Rubber Gloves (NBRr) in Saline Water

Nowadays, waste acrylonitrile butadiene rubber glove (NBRr) has been studied for use in building materials. The primary limitation of using rubber in construction was its low water absorption capacity. The goal of this research is to investigate the effect of Linear Low-Density Polyethylene (LLDPE) on water absorption and the temperature differential (20 and 30 oC) of NBRr blender composite in distilled water (DW) and saline water (SW). The rubber glove has been blended with heated two-rolled mills at 120 °C. The substance had been compressed using a hot press. Five samples had already been created. The sample was formed like a dumbbell. The five samples were immersed in DS and SW for 30 days at temperatures of 25°C and 35°C, respectively. The result shown the tensile strength, elongation at break Eb and Young’s modulus of LLDPE/NBRr blend decrease. The tensile properties of saline water lower compare to distilled water due to corrosion and degradation. Saline water contains dissolved salts, which can contribute to corrosion and degradation of the materials. The presence of salts can accelerate chemical reactions, leading to the degradation of the polymer matrix and the rubber phase. This degradation can weaken the material and reduce its tensile strength. Moreover, as the temperature increases, the thermal energy also increases, causing the polymer chains to gain more kinetic energy. This increased energy disrupts the intermolecular forces and reduces the overall molecular interactions within the material. Weaker intermolecular interactions lead to a decrease in tensile strength. As conclusion, hydrothermal effect tensile properties when temperature increase tensile properties decrease. distilled water has better diffusion than saltwater. LLDPE/NBRr blend was discovered that both distilled and salt-water absorption resulted in a decrease in tensile properties.

Lattice-Cluster-Theory-Informed Cross-Fractionation Chromatography Revealing Degree of Crystallinity of Single Macromolecular Species.

The relationship between macromolecular architecture and crystallization properties is a relevant research topic in polymer science and technology. The average degree of crystallinity of disperse polymers is a well-studied quantity and is accessible by various experimental methods. However, how the different macromolecular species contribute to the degree of crystallinity and, in particular, the relationship between a certain macromolecular architecture and the degree of crystallinity are not accessible today, neither experimentally nor theoretically. Therefore, in this work, a lattice cluster theory (LCT)-informed cross-fractionation chromatography (CFC) approach is developed to access the degree of crystallinity of single and nonlinear macromolecular species crystallizing from solution. The method entangles high-throughput experimental data from CFC with the LCT for semicrystalline polymers to predict the degree of crystallinity of polymer species with different molecular weights and branching. The approach is applied to a linear low-density polyethylene (ethylene/1-octene copolymer) and a high-density polyethylene, which have specific and different bivariate distributions. The degree of crystallinity of individual macromolecular species of these polymer samples is calculated, and the predicted average degree of crystallinity is compared with experimental measurements, thus successfully validating the approach. Furthermore, the average segment length between branches is introduced as a characteristic molecular feature of branched polyethylene, and its relationship with the degree of crystallinity of certain species is established.

Multigenerational toxicity of microplastics derived from two types of agricultural mulching films to Folsomia candida

Degradation and fragmentation of mulching films represents an increasing source of microplastics (MPs, plastic particles 1 μm to 5 mm in size) to agricultural soils. MPs have been shown to affect many soil invertebrates, including springtails. However, these studies typically use test materials representing less environmentally relevant particle types, such as pristine uniform MPs, which do not represent the large range of particle sizes and morphologies found in the field. This study aimed at providing insight into the adverse effects of MPs originating from agricultural mulching films, by using artificially aged MPs derived from both biodegradable (starch-polybutadiene adipate terephthalate (PBAT)) blend, as well as conventional (linear low-density polyethylene (LLDPE)) plastic polymers. The soil dwelling springtail Folsomia candida was exposed to these MPs for five generations in order to elucidate population effects due to possible reproduction toxicity, endocrine disruption, mutagenesis or developmental toxicity. F. candida were exposed to 0, 0.0016, 0.008, 0.04, 0.2, 1, 2, 3, 4 and 5 % (w/w dry soil) MPs in Lufa 2.2 soil, which includes concentrations within the range of environmental relevance. Juveniles produced at each concentration were transferred to the next generation, with the parental, F2 and F4 generations being exposed for four weeks and F1 and F3 generations for five weeks. No concentration-dependent effects on F. candida survival or reproduction were observed in exposures to either of the MPs, in any of the generations. These results suggest that the particular MPs used in this study, derived from mulching films used on agricultural soils, may not be potent toxicants to F. candida, even after long-term exposure and at elevated concentrations.

Synthesis and characterization of biobased copolyesters based on pentanediol: (2) Poly(pentylene adipate‐co‐terephthalate)

AbstractTraditionally, most flexible food packaging is made of linear low‐density polyethylene (LLDPE) which cannot easily be recycled, nor will it degrade in a reasonable timescale. In this work, a biobased biodegradable polyester alternative was investigated as a possible replacement for LLDPE. High molecular weight poly (pentylene adipate‐co‐terephthalate) with a 40/60 adipic acid/terephthalic acid mole ratio was synthesized using direct esterification and polycondensation. Glycerol and hexane‐1,2,5,6‐tetrol were added as branching agents to better match the structure of the LLDPE which in turn might help the ability of these materials in film‐blowing. Thermal, mechanical, and rheological properties of the copolyesters were thoroughly investigated. All copolyesters had a weight‐average molecular weight of over 140,000 g/mol, which is necessary for proper rheology, and were thermally stable up to 350°C. The addition of branching agents led to a slight decrease in crystallinity, d‐spacing, melting temperature, enthalpy of melting, stress at break, and elongation at break. However, an increase in Young's modulus and complex viscosity at high frequency were observed compared to PPeAT60 without branching agent added. Although the improved crystallinity and mechanical properties of the copolyesters made them viable for film‐blowing, the slow crystallization rate creates a major challenge.Highlights Linear and branched poly(pentylene adipate‐co‐terephthalate) (PPeAT) synthesized. Properties compared to commercial poly(butylene adipate‐co‐terephthalate) (PBAT). Glass and melting temperatures comparable to commercial PBAT. Extensional and shear viscosity comparable to commercial PBAT. PPeAT stiffness is factor of 2 higher than PBAT; ultimate properties similar.

Enhancement of insulation properties of LLDPE by PPy-functionalized PS-NPs

The strategy of functionalized PS-NPs via PPy (PPy@PS-NPs) forming heterogeneous interface composition is highly efficient in increasing the insulation properties of linear low-density polyethylene (LLDPE). The morphology results show that PPy@PS-NPs are monodispersed in the LLDPE matrix after melting blend, which exhibits unparalleled engineering application value. The electrical insulation results show that PPy@PS-NPs introduced into the LLDPE matrix can reduce its DC electrical conductivity, enhance DC breakdown strength, and inhibit space charge accumulation. When the PPy@PS-NPs concentration is 0.5 wt%, the DC breakdown strength is 35.3 % higher than that of LLDPE. Mechanism research indicates that the depths of carrier traps are decreased due to high electron affinity caused by the introduction of PPy@PS-NPs, but the trap density is increased. The reported strategy of using functionalized polymer nanoparticles to improve the polymer insulation property provides new insights for developing future high-insulation materials and other functional materials based on functionalized polymer nanofillers.

Effect of solvent type on chemical composition distribution analysis of polyolefins using crystallization elution fractionation (CEF)

For microstructure characterization of polyolefin by separation-based techniques with infrared detector, either 1,2-dichlorobenzene (o-DCB) or 1,2,4-trichlorobenzene (TCB) is commonly selected as a dissolution solvent and mobile phase. Herein, we studied the effects of o-DCB and TCB on the comonomer detection and chemical composition distribution (CCD) by crystallization elution fractionation (CEF) with a filter-based IR detector. We first compared the detector sensitivity on methyl group content or short chain branching (SCB) in polyethylene-co-butene with varied sample concentrations in o-DCB and TCB. TCB demonstrated superior comonomer detection in the IR detector with a single linear calibration across a wide range of sample concentrations. In contrast, o-DCB displayed stronger concentration dependent methyl group response, requiring a more complex equation in the calibration. Furthermore, o-DCB provided better separation of comonomer distribution with less peak broadening and co-crystallization effects, as observed with various polyolefins, including high density polyethylene (HDPE), linear low-density polyethylene (LLDPE), polypropylene (PP), and ethylene-propylene copolymer (EP).

Development and optimization of machine learning models for estimation of mechanical properties of linear low-density polyethylene

A hybrid methodology was developed and implemented for estimation of polymeric mechanical properties in rotational moulding process. The considered polymer in this study is linear low-density polyethylene, known as LLDPE, which has extensive application in plastic industry. The mechanical properties of the polymer were assessed and correlated to the oven residence time to build the predictive model of moulding process. A tiny dataset containing only 25 data rows via a number of machine learning models were assessed. Oven residence time is the only input, while the LLDPE's properties including tensile strength, impact strength, and flexure strength are the outputs considered in the machine learning models. We used tree-based ensemble methods for modeling in this work and they are tuned using FA (Firefly Algorithm) optimizer to find optimal hyper-parameters of them. Finally, the optimal models had shown a great performance to predict the output accurately. For tensile strength, the best model (FA-ET) has an R2 value of 0.9994, this score is 0.9995 for impact strength and 0.9968 for flexure strength. The tree-based models tuned in this study revealed to be robust in estimation of polymeric properties and can be used to obtain the products with the best quality.

Preparation of highly biodegradable and electron beam crosslinkable linear low-density polyethylene - based biocomposites with unique mechanical performance

Preparation of highly biodegradable and electron beam crosslinkable linear low-density polyethylene - based biocomposites with unique mechanical performance

Development of a freshness indicator packaging system using cold atmospheric plasma on LLDPE–PVA with Laponite–anthocyanin biohybrid

AbstractThis study developed a freshness indicator based on poly(vinyl alcohol) (PVA) and a biohybrid (BH) of Laponite® and anthocyanins adhered to linear low‐density polyethylene (LLDPE) using cold atmospheric plasma (CAP). LLDPE was treated with CAP for 0 to 300 s, which resulted in an increased surface energy, characterized by an important increase in its polar component up to 120 s of treatment, due to the formation of polar groups on the surface of LLDPE. No changes in mechanical properties and water vapor permeability of LLDPE were observed. LLDPE–PVA–BH films were more homogeneous if BH was added before the acidification of the film‐forming solution due to more negative zeta potential and lower particle size of BH in basic medium. Indicators made with BH were able to maintain color after 8 weeks of exposure to light, while those made with anthocyanin extract had fully degraded after 3 weeks. The freshness indicator's color changed from purple to blue and finally to green when exposed to ammonia hydroxide (30% NH3) and from purple to blue when exposed to a simulant liquid of spoiled meat (0.03% NH3). Similar color variance was observed when the indicator was applied to monitor shrimp freshness, changing from purple to blue when the shrimp pH reached pH 7.6. Thus, bilayer films of LLDPE–PVA and natural BH produced using CAP have potential food packaging applications. © 2024 Society of Chemical Industry.

Anti-Microbial, Thermal, Mechanical, and Gas Barrier Properties of Linear Low-Density Polyethylene Extrusion Blow-Molded Bottles.

Microbial contamination can occur on the surfaces of blow-molded bottles, necessitating the development and application of effective anti-microbial treatments to mitigate the hazards associated with microbial growth. In this study, new methods of incorporating anti-microbial particles into linear low-density polyethylene (LLDPE) extrusion blow-molded bottles were developed. The anti-microbial particles were thermally embossed on the external surface of the bottle through two particle deposition approaches (spray and powder) over the mold cavity. The produced bottles were studied for their thermal, mechanical, gas barrier, and anti-microbial properties. Both deposition approaches indicated a significant enhancement in anti-microbial activity, as well as barrier properties, while maintaining thermal and mechanical performance. Considering both the effect of anti-microbial agents and variations in tensile bar weight and thickness, the statistical analysis of the mechanical properties showed that applying the anti-microbial agents had no significant influence on the tensile properties of the blow-molded bottles. The external fixation of the particles over the surface of the bottles would result in optimum anti-microbial activity, making it a cost-effective solution compared to conventional compounding processing.

Optimization of Design Parameters for Improved Buoy Reliability in Wave Energy Converter Systems

Wave energy converters are frequently subjected to cyclic fatigue loads, making them prone to structural failure. This study presents a comprehensive design for reliability analysis of buoy structures used in ocean energy converters. A finite element model (FEM) was developed using ABAQUS to evaluate the effects of different materials—linear low-density polyethylene (LLDPE) versus high-density polyethylene (HDPE)—as well as variations in rib spacing and structural thickness under uniform pressure conditions. The analysis considered configurations with 3, 5, and 7 ribs, and wall thicknesses of 0.5, 0.7, and 1 inch. Results indicated that increasing the number of ribs and wall thickness significantly reduces deflection and von Mises stress, enhancing structural stability. HDPE demonstrated superior strength and lower deflection compared to LLDPE, although with reduced ductility. This study provides critical insights into optimizing buoy design parameters to improve the structural performance and durability of wave energy converter buoys, ensuring their reliability and longevity in harsh marine environments.

Charge/discharge Profiling of Organic Latent Heat Material Embedded in Polymer Matrix for Heat Energy System

The operational aspect of a latent thermal energy storage (LTES) system is highly dependent on the performance of its latent heat storage material (LHSM). In this work, performance evaluation of the LHSM is conducted using low-density polyethylene (LDPE) and linear LDPE. As an initial assessment, three different organic LHSMs are used for the evaluation. The thermal assessment indicates that the heat of fusion for the LHSM varies between 142.45 J/g and 198.8 J/g. Thermal decomposition demonstrates that the LHSM is suitable for operating a thermal power system under 100 °C. The addition of polymer clearly influences the charge/discharge rate for each LHSM. For example, it has a positive influence on paraffin wax, which increases the charge rate up to 54.4 %. A positive outcome is also observed for palmitic acid, which has the highest charge rate at around 4.4 °C/min. Interestingly, the charge/discharge rate for stearic acid is decreased by the presence of a polymer. It implies that the melting/solidification rate can be decreased, which may be advantageous for passive thermal systems. In general, the addition of LDPE/LLDPE alters the performance of LHSM. It makes the polymer suitable to be taken as a stabilizer for the LHSM.

Unlocking interfacial synergies: In situ multi-step reaction-induced control for high-performance and functional polybutylene terephthalate/polyolefin blends from recycled sources

This investigation employed free radical melt grafting technology for the synthesis of (POE/R-LLDPE)-g-(GMA-co-St) graft copolymers. Subsequently, this graft copolymer was applied as a modifier for poly (butylene terephthalate) (PBT) resin. The effects of varying recycled linear low-density polyethylene (R-LLDPE) contents in the graft on the rheological behavior, thermal properties, mechanical properties, and toughening mechanism of PBT/(POE/R-LLDPE)-g-(GMA-co-St) blends were exhaustively explored. The findings revealed that glycidyl methacrylate (GMA) and styrene (St) were effectively grafted onto the poly (ethylene-octene) (POE) and R-LLDPE molecular chains. This process enabled the epoxy groups in the GMA of the graft to react with the terminal groups of the PBT resin, thereby enhancing its compatibility with PBT. The use of R-LLDPE-g-(GMA-co-St) or POE-g-(GMA-co-St) as singular modifiers did not produce optimal modification results. Conversely, the most effective modification of the PBT resin was observed when both were combined, indicating a pronounced synergistic modification effect. The optimal overall performance of the blend was noted when the R-LLDPE content in the graft copolymer was 50 wt%. This method significantly enhanced the toughness of the blend while preserving excellent thermal stability and mechanical strength, concurrently reducing the product cost. At this point, a high concentration of voids was observed in the stress-whitening area of the impact specimens. The PBT matrix displayed conspicuous shear yielding with a notably rough impact fracture surface, manifesting highly significant tough fracture characteristics.

Effect of the Nature, the Content and the Preparation Method of Zeolite‐Polymer Mixtures on the Pyrolysis of Linear Low‐Density Polyethylene

The effect of the preparation method of the mixture catalyst/polymer on the linear low‐density polyethylene (LLDPE) pyrolysis is studied by comparing the results obtained when the polymer and the catalyst (Hβ or HZSM‐5) are extruded or simply mixed in powder form. By improving the polymer/catalyst contact through extrusion, the polymer degradation took place at lower temperature. The effect of extrusion is more pronounced with Hβ compared to HZSM‐5 owing to the highest external surface of Hβ. While the yields of gas/liquid/coke do not differ with the preparation method when HZSM‐5 is used as catalyst, more significant amount of liquid phase and high production of paraffins are observed when Hβ/LLDPE mixture is extruded, according to random scission pathway reactions. The subsequent reactions are limited by the size of the pore, which impede hydrogenation reactions, producing high molecular weight molecules. Regardless of zeolite type, the micropores of the zeolite are more affected by deactivation by coke when extrusion method is used, this effect being much more important for HZSM‐5. This result is a consequence of a polymer pre‐degradation during the extrusion process in which the first cracks of the polymer at low temperature and the first pore blockages can be generated.

Evaluating Effectiveness of Multi-Component Waste Plastic Bags on Bitumen Properties: Physical, Rheological, and Aging.

This study examines the applicability of an unknown composition waste plastic bag sample as bitumen modifier. The waste components were initially characterized to identify the type of plastics and the level of impurity. Asphalt binder performance was examined for rutting, thermal, and age resistance. The results revealed that the waste plastic bags, predominantly consisted of Low-Density Polyethylene (LDPE) and Linear Low-Density Polyethylene (LLDPE) and contained 6.1% impurities. The binder tests indicated that the waste plastic bags enhanced the rutting resistance of bitumen by one grade, with its modification more similar to LLDPE, rather than LDPE. The thermal degradation and aging properties of the modified binders demonstrated that the bitumen modified by the waste plastic bags exhibited slightly lower resistance to temperature and aging compared to virgin LDPE and LLDPE. This was attributed to the impurities contained in the waste plastic. In conclusion, the analyzed waste plastic bags proved to be suitable for use in binder modification, presenting a viable alternative to virgin LLDPE.