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Low-density polyethylene

Low-density polyethylene (LDPE) is a thermoplastic polymer derived from the free-radical polymerization of ethylene monomer under high pressure (150–350 MPa) and elevated temperatures (80–300 °C), resulting in a highly branched molecular structure that yields a density of 0.910–0.940 g/cm³.^[1] This branching distinguishes LDPE from other polyethylenes, imparting flexibility, toughness, and a lower melting point (typically 105–115 °C) compared to high-density variants.^[2] First commercialized in 1939 by Imperial Chemical Industries (ICI) for electrical insulation during World War II, LDPE has become one of the most widely produced plastics globally, with annual production exceeding 20 million tons as of 2023.^[3] Key properties of LDPE include excellent low-temperature impact resistance, chemical inertness to acids and bases, and impermeability to moisture, making it ideal for applications requiring durability and flexibility without rigidity.^[1] It is insoluble in water but softens upon exposure to hydrocarbons, and its translucent, waxy appearance allows for easy processing into thin films via extrusion or blow molding.^[4] The production process, known as the high-pressure tubular or autoclave method, initiates polymerization with organic peroxides, leading to the characteristic short- and long-chain branches that reduce crystallinity to about 40–50%.^[5] Environmental concerns have grown due to its persistence as microplastic waste, though recycling efforts target LDPE for reuse in lower-grade products.^[6] LDPE's versatility drives its primary uses in packaging, including shrink wraps, grocery bags, and food storage films, where its stretchability and barrier properties preserve contents effectively.^[7] It also features in squeeze bottles, toys, and housewares, benefiting from its low cost (around $1,000–1,500 per ton as of 2024)^[8] and ease of fabrication.^[9] Ongoing research focuses on bio-based alternatives and improved degradation methods to mitigate its environmental footprint, while innovations in copolymerization enhance specific performance traits like tear resistance; as of 2025, the LDPE market is projected to grow to $60.79 billion, driven by sustainable initiatives.^[10]^[3]

History

Discovery

The discovery of low-density polyethylene (LDPE) occurred accidentally in 1933 at the Imperial Chemical Industries (ICI) laboratory in Northwich, England, during experiments aimed at investigating high-pressure reactions of ethylene. Chemists Eric Fawcett and Reginald Gibson were attempting to polymerize ethylene with benzaldehyde to produce a potential lubricant or pressure-transmitting fluid, using a simple batch reactor setup.^[11]^[12]^[13] In their experiment on March 24, 1933, Fawcett and Gibson heated a mixture of ethylene and benzaldehyde to approximately 170°C under extreme pressures ranging from 1,000 to 3,000 atmospheres, where trace amounts of oxygen present as an unintended impurity in the apparatus served as a free-radical initiator. Instead of the expected reaction product, they isolated a white, waxy solid that proved to be a novel polymer formed solely from the ethylene monomer, as the benzaldehyde component was absent in the final material. This substance exhibited unique properties, including a softening point around 115°C and insolubility in common solvents, marking the first synthesis of polyethylene via free-radical polymerization.^[12]^[14]^[15] Initial attempts to replicate the reaction were inconsistent and often unsuccessful, attributed to variations in oxygen contamination and equipment impurities that affected the initiation of the radical chain process. To address these challenges, ICI researchers Edmond Williams, Michael Perrin, and John Paton undertook systematic experiments in 1935, refining the conditions to achieve reproducible polymerization of pure ethylene under high pressure without additional reactants.^[16]^[12] Their work confirmed the process's reliability, producing consistent batches of the waxy polymer and enabling further characterization. The material was soon recognized as a distinct form of polyethylene, characterized by its low density (around 0.92 g/cm³) resulting from irregular branching in the polymer chains induced by the high-pressure free-radical mechanism, which contrasted with the linear structures of later high-density variants developed using coordination catalysts. This branching reduced crystallinity and imparted flexibility, setting LDPE apart as a unique thermoplastic. Early analyses, including X-ray diffraction and solubility tests, supported this structural insight, though full elucidation of the branch types awaited advanced spectroscopic techniques in subsequent decades.

Commercial development

Following the accidental discovery of polyethylene by Imperial Chemical Industries (ICI) scientists Eric Fawcett and Reginald Gibson in 1933, efforts shifted toward industrial viability.^[17] ICI filed a patent application for the high-pressure polymerization of ethylene in February 1936, which was granted as British Patent 471,590 in September 1937, securing a monopoly on the process until licensing began in the 1950s.^[18] The patent described production under pressures of at least 1,200 atmospheres and temperatures of 100–300°C to yield solid polymers suitable for commercial use.^[18] The first commercial production commenced in September 1939 at ICI's facility in Heysham, England, utilizing autoclave reactors operating at 1,000–3,000 atm and 100–300°C to produce low-density polyethylene (LDPE), branded as "Polythene."^[19] Initial output was limited to around 100 tons per year, primarily for electrical insulation.^[12] During World War II, LDPE's superior dielectric properties made it essential for insulating radar cables on aircraft and ships, dramatically increasing demand and prompting secrecy around the material.^[20] This urgency led to U.S. production during World War II, with DuPont commissioned by the U.S. Navy in 1942 to build a plant under license from ICI; commercial output started in 1944 at Sabine River, Texas, marking the material's transatlantic expansion.^[19]^[21] Post-war, global LDPE production surged as licensing agreements proliferated, reaching approximately 100,000 tons annually by the early 1950s and exceeding 1 million tons by the late 1950s, fueled by applications in packaging and consumer goods.^[17] LDPE played a pivotal role in the invention of plastic bags during the 1950s, with early garbage bags developed in 1950 using the material's flexibility and waterproof qualities.^[22]

Chemical structure

Monomer and polymerization

Low-density polyethylene (LDPE) is synthesized from ethylene, a simple gaseous alkene monomer with the chemical formula C₂H₄. Ethylene is primarily derived from the steam cracking of natural gas liquids, such as ethane, or petroleum fractions like naphtha.^[23]^[24] The polymerization of ethylene to form LDPE proceeds via a free radical mechanism, which is distinct from the coordination catalysis used for high-density polyethylene.^[25] In this process, initiators such as organic peroxides or traces of oxygen generate free radicals that abstract a hydrogen from the ethylene molecule, opening its double bond and creating a reactive carbon-centered radical. This radical then propagates by adding successive ethylene monomers, forming a growing polymer chain through repeated addition across the double bonds.^[26] Chain termination occurs via radical recombination or disproportionation, while branching arises from chain transfer reactions to the polymer backbone itself, introducing short-chain branches during propagation.^[26] The overall reaction can be represented as:

n \ce{CH2=CH2} \rightarrow \ce{[-CH2-CH2-]_n}

This equation illustrates the addition polymerization, where n ethylene units link to form the polyethylene backbone, with the value of n determining the chain length. In LDPE production, the degree of polymerization typically ranges from 1,000 to 10,000 ethylene monomers per chain, corresponding to number-average molecular weights of approximately 28,000 to 280,000 g/mol.^[27] These values reflect the polydisperse nature of free radical polymerization, where chain lengths vary due to differences in initiation, propagation, and termination rates.^[25]

Branching and molecular weight

Low-density polyethylene (LDPE) exhibits a highly branched molecular structure resulting from its free radical polymerization process, which introduces both short-chain branches (SCBs) and long-chain branches (LCBs). The SCBs, primarily ethyl, butyl, and longer alkyl groups formed via intramolecular hydrogen transfer (back-biting), typically number 10–30 per 1,000 carbon atoms, while LCBs, which connect polymer chains and can extend up to hundreds of carbon units, occur at a lower frequency of 1–3 per 1,000 carbon atoms.^[28]^[29] Traditional LDPE relies on the polymerization-induced branching for its characteristic architecture. This branching disrupts chain packing, creating significant amorphous regions that enhance flexibility but limit ordered crystalline domains.^[30] In comparison to high-density polyethylene (HDPE), LDPE displays substantially higher branching levels, with approximately 2–5% of its carbons involved in branches versus less than 1% in the nearly linear HDPE. This elevated branching in LDPE results in lower crystallinity, typically 40–55%, compared to 80–90% in HDPE, as the irregular side chains hinder the formation of extended crystalline lamellae.^[31]^[32] Consequently, LDPE's molecular architecture leads to reduced density (0.917–0.930 g/cm³) and poorer packing efficiency relative to HDPE's more linear chains.^[29] The molecular weight distribution of LDPE is notably broad due to random chain termination and transfer reactions during free radical polymerization, yielding a polydispersity index (PDI, defined as Mw/Mn) typically ranging from 4 to 20. This wide distribution, far broader than the PDI of 2–4 for many linear polyethylenes, influences melt rheology by promoting shear thinning and enhancing processability in extrusion applications.^[33] The resulting varied chain lengths contribute to LDPE's unique balance of flow properties and mechanical performance.

Production

High-pressure process

The high-pressure process is the primary industrial method for synthesizing low-density polyethylene (LDPE), involving the free radical polymerization of ethylene in specialized reactors under extreme conditions. This process typically operates in either tubular or autoclave reactors at pressures ranging from 1,000 to 3,000 bar (approximately 15,000 to 45,000 psi) and temperatures between 150 and 350°C, achieving monomer conversions of 15-30% per pass.^[34]^[35] The elevated pressure suppresses chain transfer reactions and promotes branching, resulting in the characteristic low density and flexibility of LDPE, while the high temperatures facilitate initiator decomposition and reaction propagation. Ethylene is compressed in multi-stage systems to reach these pressures, with careful control to prevent adiabatic heating that could lead to runaway reactions.^[36] Initiation in the high-pressure process relies on organic peroxides, such as benzoyl peroxide or tert-butyl peroxy compounds, which are injected at multiple points along the reactor to generate free radicals and control the polymerization rate. These initiators decompose thermally under the process conditions, with their selection and dosing tailored to achieve desired molecular weight and branching levels; traces of oxygen may also be used in some variants to modulate radical formation at lower pressures within the range.^[37]^[38] The free radical mechanism, involving initiation, propagation, and termination steps, drives the formation of branched polymer chains, as outlined in the monomer and polymerization subsection.^[39] Reactor design significantly influences product properties: autoclave reactors provide a broader residence time distribution due to back-mixing, leading to more uniform long-chain branching and a wider molecular weight distribution suitable for applications requiring enhanced processability. In contrast, tubular reactors operate under plug-flow conditions at higher pressures, yielding a narrower molecular weight distribution and improved optical clarity in films due to reduced branching variability.^[40]^[41] Both types require precise temperature profiling along the reaction zones to manage the exothermic reaction and prevent hotspots.^[42] The process demands substantial energy input, typically 10-20 kWh per kg of LDPE produced, primarily for compression and heating, with overall efficiencies improved by recycling unreacted ethylene. Byproducts such as waxes and oligomers, formed from side reactions, are separated via devolatilization and purification steps post-reactor to ensure product purity.^[43]^[44] This separation is critical for downstream pelletization and to minimize waste in the highly energy-intensive operation.^[45]

Additives and variations

Low-density polyethylene (LDPE) formulations are often modified by incorporating additives to enhance stability, processability, and performance during manufacturing and end-use. Common additives include antioxidants such as hindered phenols, typically added at concentrations of 0.1-0.5% by weight to inhibit oxidative degradation during processing and storage.^[46] Slip agents like erucamide, a fatty acid amide, are incorporated at low levels (around 0.1-0.2%) to reduce surface friction and facilitate mold release in film and extrusion applications.^[47] For outdoor applications, UV stabilizers such as hindered amine light stabilizers (HALS) are blended into LDPE to protect against photodegradation from ultraviolet exposure, extending the material's service life in environments like agricultural films or packaging.^[48] Copolymer variants of LDPE incorporate comonomers to tailor flexibility and other attributes while maintaining a base ethylene structure. Ethylene-vinyl acetate (EVA) copolymers, with vinyl acetate content typically ranging from 5-20%, exhibit improved flexibility due to reduced crystallinity compared to pure LDPE.^[49] Similarly, ethylene-butyl acrylate (EBA) copolymers, featuring 5-20% butyl acrylate comonomer, provide enhanced low-temperature performance and adhesion properties suitable for flexible films and coatings.^[50] These comonomers introduce short branches that modify the polymer's rheological behavior without altering the high-pressure polymerization core. A related variation is linear low-density polyethylene (LLDPE), which, while distinct from traditional LDPE, shares similar density ranges but achieves controlled short-chain branching through copolymerization of ethylene with alpha-olefins using Ziegler-Natta catalysts under low-pressure conditions.^[29] This results in a more linear structure with uniform branches, offering better mechanical properties for applications like stretch films, though it requires different processing than branched LDPE.^[51] Processing aids and variations further customize LDPE through masterbatches, which are concentrated dispersions of pigments or colors in a carrier resin, added at 1-5% to achieve desired hues without compromising homogeneity in extrusion or molding.^[52] For foamed LDPE variants used in insulation or packaging, blowing agents such as pentane are introduced to generate gas during expansion, creating cellular structures that reduce density and improve thermal insulation.^[53]

Physical properties

Density and crystallinity

Low-density polyethylene (LDPE) exhibits a density typically ranging from 0.917 to 0.930 g/cm³ at 23°C, as measured by the ASTM D792 standard method involving immersion in a liquid medium to determine specific gravity.^[54] This density is lower than that of high-density polyethylene (HDPE), which ranges from 0.941 to 0.965 g/cm³, primarily due to the branched molecular structure of LDPE that introduces voids and increases free volume between polymer chains, reducing overall packing efficiency.^[32] LDPE is a semicrystalline polymer with a crystallinity degree of 40-55%, characterized by an orthorhombic crystal lattice structure where polyethylene chains align in a folded conformation within lamellar domains.^[55] Crystallinity levels are quantified using differential scanning calorimetry (DSC), which measures the heat of fusion and compares it to the theoretical value for perfect polyethylene crystals (293 J/g).^[55] Branching in LDPE limits the size of crystalline lamellae to 10-20 nm in thickness by disrupting chain folding and regularity, thereby increasing the amorphous content compared to linear polyethylenes.^[56] Additionally, the cooling rate during processing significantly affects amorphous content; faster cooling rates restrict crystal growth time, resulting in higher amorphous fractions and lower overall crystallinity.^[57] LDPE's density below 1 g/cm³ allows it to float in water, facilitating applications requiring buoyancy such as marine floats and lightweight packaging.^[58]

Thermal characteristics

Low-density polyethylene (LDPE) exhibits a glass transition temperature of approximately -120°C in its amorphous regions, marking the point where the polymer transitions from a glassy to a rubbery state, which contributes to its flexibility at low temperatures.^[59] The melting point, determined by differential scanning calorimetry (DSC) as the peak of the endothermic transition, typically ranges from 105°C to 115°C, influenced by the degree of branching and crystallinity that affects the melt behavior.^[60] The Vicat softening temperature for LDPE falls between 85°C and 95°C, indicating the point at which the material begins to deform under a specified load.^[61] For practical applications, LDPE has a continuous use limit of about 65°C, beyond which prolonged exposure may lead to softening or dimensional changes, while short-term exposure up to 90°C is tolerable without significant deformation.^[62] LDPE demonstrates low thermal conductivity, ranging from 0.33 to 0.44 W/m·K, making it an effective insulator in applications requiring heat retention or barrier properties.^[63] Its coefficient of linear thermal expansion is relatively high, at 100–200 × 10^{-6}/°C, which can influence dimensional stability during temperature fluctuations.^[54] Regarding heat resistance, LDPE begins to undergo significant thermal degradation above approximately 400°C through random chain scission mechanisms, leading to molecular weight reduction and potential volatilization.^[64] In terms of flammability, LDPE is classified under UL94 HB, indicating horizontal burning with slow flame spread and low smoke emission compared to more rigid polymers.^[65]

Mechanical properties

Strength and flexibility

Low-density polyethylene (LDPE) demonstrates moderate tensile strength, typically ranging from 10 to 20 MPa as measured by ASTM D638, which is lower than that of high-density polyethylene owing to the material's extensive branching that reduces intermolecular forces and crystallinity.^[66]^[67] The yield strength falls in the range of 8 to 12 MPa under similar testing conditions, reflecting LDPE's ability to deform plastically before significant hardening.^[68]^[67] A hallmark of LDPE's mechanical behavior is its high elongation at break, often 400% to 600%, which imparts substantial ductility and toughness, allowing the material to stretch extensively without fracturing.^[68]^[67] This property arises from the polymer's amorphous regions and chain entanglement, enabling energy dissipation through large deformations. In terms of flexibility, LDPE has a Young's modulus of 150 to 300 MPa, which facilitates bending and shaping without cracking, complemented by a Shore D hardness of 45 to 55 that balances softness with sufficient rigidity for practical use.^[68]^[69]^[67] The stress-strain response of LDPE is characteristically nonlinear, featuring an initial elastic region followed by yielding, necking, and extensive drawing that promotes uniform elongation and high energy absorption prior to failure.^[70] This behavior underscores LDPE's suitability for applications requiring resilience under tensile loads, where the necking phenomenon localizes deformation but propagates through drawing to maintain structural integrity over large strains.^[70]

Other mechanical attributes

Low-density polyethylene (LDPE) exhibits high impact strength, attributed to its viscoelastic nature, which allows energy dissipation through molecular chain mobility and branching. The notched Izod impact strength is typically high, often resulting in no break (>500 J/m) according to ASTM D256, making it suitable for applications requiring toughness without brittleness.^[71] For thin films, dart drop impact resistance often exceeds 300 g, demonstrating LDPE's ability to withstand punctures and sudden loads in flexible packaging.^[72] Abrasion resistance in LDPE is moderate compared to other engineering plastics, reflecting its soft surface that wears under frictional stress but maintains integrity in low-wear environments. This property supports its use in non-abrasive contact applications, where surface scuffing is minimal. LDPE demonstrates good resistance to fatigue under cyclic loading, as evidenced by laboratory studies on static and dynamic fatigue testing, which show minimal crack propagation in bulk specimens over repeated stress cycles.^[73] Its creep behavior is characterized by a creep modulus of approximately 40 to 100 MPa under a 1 MPa load at 23°C, indicating moderate long-term deformation resistance suitable for sustained low-stress conditions.^[74] Tear strength for LDPE films measures 200 to 400 g via the Elmendorf method (ASTM D1922), enabling reliable propagation resistance in flexible structures like bags and wraps, where directional tear control is essential for packaging integrity. This attribute, combined with inherent flexibility, enhances LDPE's performance in dynamic tearing scenarios.^[75]^[76]

Chemical properties

Resistance and reactivity

Low-density polyethylene (LDPE) exhibits significant inertness to a variety of common chemicals at room temperature, showing no significant reaction or degradation when exposed to water, dilute acids such as hydrochloric and sulfuric (up to 60%), dilute bases like potassium hydroxide, alcohols including ethanol and methanol, and aliphatic hydrocarbons such as hexane.^[77]^[78] This chemical stability arises from LDPE's non-polar hydrocarbon structure, which resists hydrolysis and ionization by these agents, making it suitable for applications involving aqueous or mildly aggressive environments. However, LDPE demonstrates limited compatibility with aromatic solvents like toluene, where exposure leads to swelling and partial softening due to solvent diffusion into the amorphous regions of the polymer.^[77]^[78]^[79] In contrast, LDPE reacts adversely with strong oxidizing agents, undergoing chemical attack that results in polymer degradation, including chain scission. Halogens such as chlorine (gaseous or moist) and bromine cause severe effects, leading to bond breakage and material embrittlement, while fuming sulfuric acid and concentrated nitric acid (>95%) similarly induce oxidative cleavage of the polyethylene chains.^[78]^[79]^[80] These reactions are driven by the electrophilic nature of the oxidizers, which abstract hydrogen atoms and initiate radical mechanisms that propagate along the polymer backbone, reducing molecular weight and mechanical integrity.^[81] LDPE displays high permeability to gases, particularly non-polar ones like oxygen, with transmission rates typically ranging from 4,500 to 7,500 cm³·mil/m²·day·atm at standard conditions, owing to the polymer's low crystallinity and flexible chains that allow facile diffusion.^[82] In comparison, its permeability to water vapor is relatively low, at approximately 15-25 g·mil/m²·day, providing a modest barrier against moisture despite the material's overall hydrophobicity.^[83] These permeation characteristics stem from the size and solubility of penetrants in the LDPE matrix, with smaller, non-interacting molecules like O₂ permeating more readily than polar water vapor.^[84] The electrical properties of LDPE contribute to its reactivity profile in non-chemical contexts, featuring a low dielectric constant of 2.2-2.4 at 1 kHz and exceptionally high volume resistivity exceeding 10¹⁵ ohm·cm, which minimizes ionic conduction and dielectric losses under electric fields.^[65]^[63]^[85] This insulation behavior is attributed to the absence of polar groups in the polymer, ensuring low reactivity with electromagnetic stressors and supporting its use in electrical applications without significant charge accumulation or breakdown.^[65]

Stability and degradation

Low-density polyethylene (LDPE) exhibits limited oxidative stability when exposed to ultraviolet (UV) light, primarily undergoing photo-oxidation that initiates free radical formation and leads to the production of hydroperoxides as initial intermediates.^[86] These hydroperoxides decompose into macroradicals, resulting in the formation of carbonyl compounds, chain unsaturation, and carboxylic acids, which cause chain scission, surface embrittlement, and reduced mechanical integrity, mainly affecting a 500–900 micron surface layer.^[86] Without UV stabilizers, such as absorbers or quenchers, LDPE experiences accelerated degradation outdoors, with significant loss of tensile strength (nearly 50%) observed after about 7 months of exposure in high-UV environments like Florida.^[87] Additives like hindered amine light stabilizers, incorporated during production, can extend this lifetime by retarding radical propagation. Thermal degradation of LDPE occurs above 200°C through random chain scission, producing volatile hydrocarbons such as ethylene and butene as primary products.^[88] This process follows a one-step pyrolysis mechanism with an activation energy of 215–221 kJ/mol, as determined by isoconversional methods like Friedman and Flynn–Wall–Ozawa.^[88] The degradation yields a broad distribution of oligomers and gases, with the reaction rate increasing significantly at higher temperatures due to enhanced bond breaking in the polymer backbone. LDPE demonstrates excellent hydrolytic stability owing to its non-polar C–C and C–H bonds, which resist hydrolysis under aqueous conditions across a wide pH range. Unlike heteroatom-containing polymers, LDPE does not undergo hydrolytic chain cleavage, making it highly inert to water and maintaining structural integrity in moist environments. Biodegradation of LDPE is minimal in natural settings, with weight loss rates of 0.1–1% reported in soil or compost over several years under ambient conditions. Recent investigations have detected trace microbial activity, including methane emissions from LDPE at 5.8 nmol/g/day when incubated under ambient solar radiation for 212 days.^[89] This slow process primarily involves surface erosion by consortia of bacteria and fungi, but overall mineralization remains negligible without pretreatment.

Applications

Packaging

Low-density polyethylene (LDPE) plays a dominant role in packaging applications due to its flexibility, clarity, and excellent heat-sealability, making it ideal for consumer and industrial containment solutions. Packaging accounts for approximately 58% of global LDPE consumption, with projections estimating around 15 million tons annually by 2025 as total LDPE production reaches about 26 million tons.^[90]^[91] Plastic films and bags represent the largest segment of LDPE use, comprising 60-70% of total LDPE applications, primarily in shrink and squeeze films for food packaging such as bread bags and resealable storage bags. LDPE's high clarity allows for product visibility, while its superior sealability ensures airtight closures that preserve freshness and prevent contamination.^[92]^[93]^[94] In bottles and containers, LDPE is widely used for squeeze bottles in personal care products like shampoos and lotions, holding a significant market share of 20-50% in flexible dispensing packaging due to its squeezability and chemical resistance. It also enables flexible pouches for liquids, providing lightweight, leak-proof options for items such as sauces and detergents.^[95]^[96]^[97] Expanded LDPE (EPE) foam is employed in protective packaging for electronics and fragile items, offering cushioning through its closed-cell structure and typical expansion ratios of 3-40 times, which provide a high strength-to-weight ratio for impact absorption.^[98]^[99]

Other uses

Low-density polyethylene (LDPE) is widely utilized as an insulating material for wires and cables due to its excellent dielectric properties, including low dielectric loss, which minimizes energy dissipation in electrical transmission.^[100] This makes it suitable for medium-voltage power cables, where it provides reliable electrical insulation and thermal stability, often rated for continuous operation up to 90°C in non-crosslinked forms.^[101] Manufacturers like Dow produce specialized LDPE compounds for these applications, enhancing curing speed and weather resistance for outdoor cable systems.^[102] In the medical and laboratory sectors, LDPE serves as a key material for flexible tubing and bags used in intravenous (IV) fluid delivery, owing to its chemical inertness and biocompatibility, which prevent reactions with bodily fluids or pharmaceuticals.^[103] These properties ensure sterility during storage and transport, with LDPE bags commonly employed for gamma irradiation sterilization to maintain product integrity without compromising the material's durability.^[104] LDPE's flexibility and moisture resistance also make it ideal for laboratory equipment components, such as squeeze bottles and disposable containers, supporting safe handling in clinical environments.^[105] LDPE plays a vital role in construction through geomembranes, which act as impermeable barriers for moisture control in landfills and water containment systems, leveraging the material's flexibility and chemical resistance.^[106] In building applications, it is formulated into housewraps that provide vapor-permeable yet water-resistant layers for exterior walls, enhancing energy efficiency and protection against environmental elements.^[107] For agriculture, UV-stabilized LDPE grades are extensively used in greenhouse films, offering durability against sunlight degradation while allowing light transmission to promote plant growth in controlled environments.^[108] Emerging applications of LDPE include 3D printing filaments, where its flexibility and impact resistance enable the production of prototypes and custom parts, though challenges like thermal expansion require specialized extrusion techniques.^[109] In consumer products, LDPE is favored for toys such as squeeze toys, benefiting from its soft, resilient nature that withstands repeated deformation without cracking.^[110] Globally, non-packaging uses of LDPE, encompassing these industrial, medical, construction, and emerging sectors, account for approximately 40-50% of total production, highlighting its versatility beyond disposable items.^[111]

Environmental considerations

Impact and pollution

Low-density polyethylene (LDPE) contributes significantly to microplastic pollution in marine environments, as its films and fragments degrade into particles smaller than 5 mm through weathering and mechanical action. These LDPE-derived microplastics constitute approximately 20% of global plastic waste entering oceans, forming a major portion of the approximately 170 trillion microplastic particles on the ocean surface as estimated in a 2020 study, with totals exceeding this when including deeper waters and sediments as of 2025.^[112]^[113]^[114] Due to their chemical stability, LDPE microplastics persist in the ocean for over 100 years, resisting complete biodegradation and accumulating in sediments and water columns.^[115]^[116] The production of LDPE generates substantial greenhouse gas (GHG) emissions, with cradle-to-gate assessments indicating approximately 1.9 tons of CO₂ equivalent per ton of LDPE resin. At the end-of-life stage, LDPE exposed to sunlight undergoes photochemical degradation, releasing methane at a rate of 5.8 nmol per gram per day after prolonged exposure, alongside other hydrocarbons like ethylene. With global LDPE production estimated at around 23 million tons in 2025, these emissions exacerbate climate change, particularly as less than 10% of LDPE is recycled, leading to widespread accumulation in landfills and oceans.^[43]^[117]^[118] LDPE pollution harms wildlife and ecosystems, notably through ingestion by marine species. For instance, around 35-60% of seabirds worldwide have ingested plastics, including LDPE fragments mistaken for food, leading to internal blockages, starvation, and reduced reproductive success.^[119] Additionally, LDPE can leach additives such as phthalates into surrounding environments, contaminating water and soil; these endocrine-disrupting chemicals bioaccumulate in food webs, posing risks to aquatic organisms and human health via seafood consumption.^[120]

Recycling and sustainability

Low-density polyethylene (LDPE) is identified by recycling code #4, which facilitates its sorting in waste streams for recovery processes.^[121] Mechanical recycling of LDPE primarily involves melt extrusion, typically conducted at temperatures between 180°C and 220°C, to process collected waste into pellets for reuse. This method achieves 80-90% retention of original mechanical properties in initial cycles, though repeated processing leads to chain scission and reduced molecular weight. A key limitation is color degradation, where pigments and contaminants accelerate oxidative changes during extrusion, often resulting in darker recyclates unsuitable for high-visibility applications.^[122]^[123]^[124] Global recycling rates for LDPE remain low, estimated at 5-10% of generated waste, reflecting challenges in collection and processing infrastructure. In the United States, the LDPE recycling rate was 5.7% in 2016, remaining below 5% as of 2025 despite expanded curbside programs and industry commitments.^[125] Chemical recycling offers an alternative, particularly through pyrolysis, which thermally decomposes LDPE at 400-600°C to recover ethylene monomers with yields of 70-80% for valuable hydrocarbons, enabling closed-loop production without quality loss from mechanical methods.^[126] Sustainability initiatives include bio-based LDPE derived from sugarcane ethanol, pioneered by Braskem's industrial plant in Triunfo, Brazil, operational since 2010 with an initial capacity of 200,000 metric tons per year. This renewable variant reduces reliance on fossil feedstocks while maintaining identical performance to conventional LDPE. Additionally, CO2-derived LDPE variants, produced via carbon capture and polymerization, can cut fossil carbon input by up to 50% compared to traditional routes, supporting lower greenhouse gas emissions when powered by renewables.^[127]^[128] Despite these advances, contamination from food residues and mixed plastics poses significant challenges, reducing recyclate purity and economic viability. By 2025, emerging trends include pilot-scale enzymatic degradation using engineered microbes to break down LDPE into monomers, addressing its inherent low biodegradability. Circular economy policies, such as the European Union's Packaging and Packaging Waste Regulation (PPWR) targets, which include 25-30% recycled content for plastic bottles and 10-35% for other plastic packaging elements by 2030, are driving investments to boost LDPE recovery rates and integrate sustainable practices across supply chains.^[129]^[130]^[131]

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Solid polymers of ethylene are produced (a) by subjecting ethylene, compressed to a pressure of at least 1200 ats., to a temperature of 100--300 DEG C., ...Missing: 1934 | Show results with:1934
[19]
Polyethylene (low density) - The Plastics Historical Society
Dec 6, 2016 · The first plant came into operation in September 1939 and the resultant product, named "Polythene" by ICI, was to have a major impact on the war ...
[20]
From Coal Tar to Crafting a Wealth of Diversity - ACS Publications
Jan 12, 1998 · During the war years, LDPE was used for electrical insulation for ship and airborne radar systems. Union Carbide had also produced LDPE at about ...
[21]
https://www.hy-ram.co.uk/the-history-of-polyethylene-electrofusion-welding/
[22]
Cracking and related refinery processes
Cracking, as the name suggests, is a process in which large hydrocarbon molecules are broken down into smaller and more useful ones.
[23]
Ethylene: The “World's Most Important Chemical”
Sep 6, 2017 · Oil or natural gas is heated with steam to crack apart molecular bonds, and the ethylene gas emitted is separated and sent to processing plants.Missing: source | Show results with:source
[24]
(PDF) Free Radical Polymerizations: LDPE and EVA - ResearchGate
Oct 17, 2024 · Commercially a very flexible and branched LDPE is produced through free radical polymerization of ethylene (monomer), in the presence of ...
[25]
The Free Radical, High Pressure Polymerization of Ethylenes. The ...
The mechanism of the high‐pressure free radical polymerization ... Ethylene‐Polyethylene Mixtures in the Industrial Production of Low Density Polyethylene.
[26]
Polyethylene - an overview | ScienceDirect Topics
The molecular weight of polyethylene can vary from 30,000–6,000,000 g/mol, density can range from 0.91–0.98 g/cc, and crystallinity can span 30–90%. The melting ...
[27]
advanced analysis of a systematic set of mini-plant scale low density ...
Apr 27, 2021 · While LDPE typically exhibits 10–30 SCBs per 1000 carbon atoms, the LCB density is only 1–3 per 1000 carbon atoms. SCBs affect mainly the ...
[28]
Poly(ethene) (Polyethylene) - The Essential Chemical Industry
There are about 20 branches per 1000 carbon atoms. The relative molecular mass, and the branching, influence the physical properties of LDPE. The branching ...
[29]
Short-chain Branching in polyolefins: causes and how to study them.
Jul 20, 2021 · Polyolefin copolymer resins incorporate comonomers such as 1-butene, 1-hexene, or 1-octene, which results in short-chain branches irregularly added.Missing: 20-40 side<|control11|><|separator|>
[30]
LDPE vs HDPE - Chembook
Realize that my example is a bit extreme, but the fact is that HDPE is way less branched (almost no branching) than LDPE (about 2% of the carbons have branching) ...Missing: percentage | Show results with:percentage
[31]
Density Polyethylene - an overview | ScienceDirect Topics
Polyethylene is produced in three main forms: low density (<0.930 g/cm3), linear low density (0.915–0.940 g/cm3), and high density (0.940–0.965 g/cm3). The high ...5.3 Polyethylene (pe) · Rotational Molding Polymers · 2.3 Polyethylene Types
[32]
[PDF] Comparison Study of Model Based Industrial Low-Density ... - Aidic
Average Molecular Weight (Mn), Weight Average Molecular Weight (Mw) and Polydispersity Index (PDI) The rate constants of propagation and initiation for all ...
[33]
Low-density polyethylene simulated production in high pressure ...
Jan 10, 2023 · This free radical polymerization occurs in a tubular reactor under harsh working conditions with a variety of initiators present.Missing: yield | Show results with:yield
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[PDF] DYNAMIC OPTIMIZATION OF LOW-DENSITY POLYETHYLENE ...
Jul 16, 2020 · The monomer conversion (XM) in the tubular reactor is reported to be very low, which is in the range of 20–30% per pass [8]. Considering the.
[35]
High-Pressure Polymerization - an overview | ScienceDirect Topics
The polymerisation reaction takes place in tubular or stirred vessel reactors (d) under careful control of pressure and temperature, enhanced or initiated by ...
[36]
[PDF] Polymerization of monomers with Organic Peroxide for ... - PERGAN
The main areas of application for these initiators are the production of low density polyethylene (LDPE), polyvinylchloride (PVC), styrenics (PS/EPS), acrylics.
[37]
High pressure, free radical polymerizations to produce ethylene ...
In one embodiment, these organic peroxide initiators are used in an amount from 0.001 to 0.2 wt%, based upon the weight of polymerizable monomers. Peroxide ...
[38]
[PDF] Safety of organic peroxides - Nouryon
For example dry dibenzoyl peroxide is shock-sensitive, so that the probability of an explosion effect being initiated by mechanical treatment is very high. The ...
[39]
[PDF] Tubular LDPE has the Extrusion Coating future. - TAPPI.org
Approximately 50-60 years ago, the first commercial extrusion coating process started up, the plastic for coating was Low Density Poly Ethylene (LDPE).<|separator|>
[40]
High molecular weight tail and long‐chain branching in low‐density ...
Apr 5, 2001 · The reason for the tubular resins showing such differences in molecular weight distribution and LCB concentration in comparison to autoclave ...
[41]
and micro-mixing in the low-density polyethylene autoclave reactor
In general, the LDPE produced in the autoclave reactor has more long chain branched structures and wider molecular weight distribution, due to the much more ...
[42]
[PDF] Cradle-to-Gate-Life-Cycle-Analysis-of-Low-Density-Polyethylene ...
Apr 30, 2020 · The renewable energy demand consists of landfill gas used for process energy in olefins production and electricity derived from renewable energy ...
[43]
[PDF] Eco-profiles of the European Plastics Industry LOW DENSITY ...
The average gross energy to produce 1 kg of low density polyethylene is 77 MJ ... Gross water consumption required for the production of 1 kg of low ...
[44]
[PDF] LDPE Production from Ethylene (High-Pressure Tubular Process)
Net Utility Consumption Rates (per mt of LDPE) ... The chemicals employed in this process include a mixture of organic peroxides (used as initiators) diluted in.
[45]
Stabilisation of LDPE cross-linked in the presence of peroxides I ...
Without the peroxide, Irganox 1081, at concentrations in the range 0.1–0.5% w/w, was found to inhibit LDPE oxidation. Its depletion rate at temperatures in the ...
[46]
[PDF] vote sheet for plastics determinations NPR
• Anti-blocking agents: Fine silicas are an example of a PE antiblocking agent;. • Slip agents: PE slip agents include fatty amides such as oleamide and ...
[47]
Process & Function Additive for LDPE Plastic - baoxu chemical
UV Stabilizer for LDPE ... UV stabilizers contain two types of light stabilizers: Ultraviolet Light Absorbers (UVA) and Hindered-Amine Light Stabilizers (HALS), ...
[48]
[PDF] GENERAL EXTRUSION GUIDE CELANESE EVA POLYMERS
For EVA copolymers, the acetate groups decrease crystallinity (and therefore increase flexibility) but increase density due to the greater molecular weight of ...
[49]
EBA - Material Data Center
... comonomers to produce ethylenevinyl acetate copolymer (EVA), ethylene-butylacrylate copolymer (EBA) and ethylenemethylacrylate copolymer (EMA). The current ...
[50]
Polyethylene (PE Plastic) – Structure, Properties & Toxicity
Jul 9, 2025 · LDPE is produced at high pressure (1000-3000 bar) and temperature (80-300°C). It is derived via the free radical polymerization process. Two ...<|control11|><|separator|>
[51]
Thermoplastic Masterbatches & Liquid Dispersions vs. Raw Pigments
Thermoplastic masterbatches, and liquid dispersions improve the strength of pigments, reduce color variability, reduce environmental health and safety concerns.
[52]
Why Use Pentane as a Blowing Agent in Foam Production? - Trecora
Pentane is attractive as a blowing agent for foam production because it is comparatively inexpensive. It is also readily available.
[53]
Polyethylene (Low Density) LDPE, LLDPE
65 oC. Density 0.917 - 0.930 g/cm3. RESISTANCE TO CHEMICALS Dilute Acid **** Dilute Alkalis **** Oils and Greases ** variable. Aliphatic Hydrocarbons ...Missing: source | Show results with:source
[54]
[PDF] characterization of melting phenomena in linear low density ...
The total heat of fusion associated with this peak is 140 J/g, which corresponds to 48% crystallinity based on the reported theoretical value of 293 J/g for ...
[55]
Reassessing chain tilt in the lamellar crystals of polyethylene - Nature
Sep 21, 2023 · Flexible polymer chains fold regularly to form 10–20-nm-thick lamellar crystals (folded-chain crystals; FCCs), which grow with 10–20-nm-thick ...
[56]
The Effect of the Cooling Process on the Crystalline Morphology and ...
Jun 20, 2020 · In this study, LDPE samples were prepared by melt blending with different cooling processes, which were natural air cooling, rapid air cooling, water cooling ...
[57]
Solved: Water has a density of 1.0g/cm^3. A substance called LDPE ...
Rating 5.0 (2) Since the density of LDPE (0.91 g/cm^3) is less than the density of water (1.0 g/cm^3), LDPE will float on water. This is because objects with a lower density ...
[58]
PE-LD: Polyethylene low density - NETZSCH Polymers
Glass Transition Temperature: -130 to - 100/-30 to -10 °C ; Melting Temperature: 100 to 115 °C ; Melting Enthalpy: - J/g ; Decomposition Temperature: 487 to 498 °C ...
[59]
[PDF] LOW DENSITY POLYETHYLENE - MOL
It is stable in the temperature range from −50 to 85°C, the melting point is from 105 to 115°C. In the oxygen absence LDPE is stable up to 290 °C. It decomposes ...
[60]
[PDF] Data Sheet: LDPE
(Low Density Polyethylene) ... Glass transition temperature [°C]. -110. Vicat softening temperature [°C]. 89. Coefficient of thermal expansion [K-1 · 10-6].
[61]
What Is the Service Temperature of LDPE? - Polymer Molding
Oct 14, 2022 · This thermoplastic retains its shape all the way down to minus 40 degrees Celsius and up to 65 degrees Celsius (149 degrees Fahrenheit). ...Missing: continuous | Show results with:continuous
[62]
Thermoplastic Low Density Polyethylene (LDPE) - SubsTech
Dec 14, 2023 · Thermal expansion (20 ºC), 16*10-5, ºCˉ¹, 9*10-5, in/(in* ºF). Thermal conductivity, 0.33, W/(m*K), 2.29, BTU*in/(hr*ft²*ºF). Melting point, 120 ...Missing: glass transition Vicat softening heat degradation flammability<|control11|><|separator|>
[63]
[PDF] Thermal degradation studies of LDPE containing cobalt stearate as ...
for neat LDPE increased from 3.67 to 7.56 after. 600 h of thermal exposure at 70°C, which is indica- tive of chain scission resulting in lower molecular weight.<|separator|>
[64]
Low Density Polyethylene - LDPE - AZoM
May 11, 2001 · Typical Properties ; Oxygen Index (%), 17 ; Flammability UL94, HB ; Volume Resistivity (log ohm.cm), 16 ; Dielectric Strength (MV/m), 27.
[65]
Polyolefins - Plastics Europe
... low-density polyethylene, HDPE has little branching, giving it stronger intermolecular forces and tensile strength than LDPE. It is also harder and more ...
[66]
Overview of materials for Low Density Polyethylene (LDPE), Film ...
Overview of materials for Low Density Polyethylene (LDPE), Film Grade ; Tensile Strength, Ultimate, 7.85 - 34.5 MPa. 1140 - 5000 psi. Average value: 13.2 MPa ...
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https://www.lookpolymers.com/polymer_Overview-of-materials-for-Low-Density-Polyethylene-LDPE-Film-Grade.php
[68]
LDPE - Plastics International
Thermal Conductivity. Coefficient of Linear Thermal Expansion, 6.40 x 10^5. Flammability Rating, Not Rated. Electric/Physical Properties. Volume Resistivity, 10 ...
[69]
Static and Dynamic Properties of Semi-Crystalline Polyethylene - PMC
The typical engineering stress-strain curves of LDPE and UHMWPE at two strain rates and a range of strain that results in failure are shown in Figure 7.
[70]
https://pmc.ncbi.nlm.nih.gov/articles/PMC6432432/
[71]
[PDF] Novel non-barrier liquid packaging solution - ExxonMobil Chemical
... LDPE ○Market reference with up to 40% LDPE. *ExxonMobil estimate ... 300 g. Dart Drop Impact (Method A), g. 240 MPa. 265 MPa. 290 MPa. 315 MPa. 340 MPa.
[72]
US20180036092A1 - Package for a medical device - Google Patents
B29K2023/0633 LDPE, i.e. low density polyethylene. B PERFORMING OPERATIONS ... 85-90. Taber Abrasion, D-3489, 1-50 mg loss. (H-18, 1000 g load, 10-50 mg loss.
[73]
Mechanical and Thermal Degradation-Related Performance of ... - NIH
Oct 10, 2024 · This paper presents research aimed at laboratory experiments on static and cyclic fatigue testing of low-density polyethylene (LDPE) ...
[74]
[PDF] SABIC® LDPE 1965N0
Vicat Softening Temperature (5) (6) at 10 N (VST/A). 75. °C. ISO 306. © 2017 Copyright by SABIC. All rights reserved. Page 2. DSC test melting point. 104. °C.<|separator|>
[75]
Tear Strength: Definition, Relation to 3D Printing, Formula, Unit, and ...
Mar 23, 2023 · LDPE, on the other hand, has an Elmendorf tear strength of 320g MD and 170g TD. What Are the Types of Materials With High Tear Resistance? In ...
[76]
[PDF] TRICOLENE® LDF2922
TYPICAL VALUE (METRIC). ASTM. Melt Index. 2.2 g/10 min. D 1238. Density. 0.922 g/cm³. D 792. Thickness. 1.5 mil. 38 µm. Tear Strength (MD/TD). 168/300 g. D 1922.<|separator|>
[77]
None
### LDPE Chemical Resistance Summary
[78]
None
### Summary of Polyethylene (PE) Chemical Resistance, Focusing on LDPE
[79]
[PDF] Chemical Resistance Chart for LDPE (Low Density Polyethylene)
Chemical Resistance Classification: A = Excellent. B = Good, Minor Effect, slight corrosion or discoloration. C = Fair, Moderate Effect, not recommended for ...Missing: reactivity | Show results with:reactivity
[80]
Electrochemical Oxidation and Functionalization of Low‐Density ...
Apr 13, 2023 · The copper and nickel electrode/electrolyte pairs showed a promising capability for oxidation and chain-scission of LDPE. In contrast, the ...
[81]
[PDF] degradation of ldpe lldpe and hdpe in film extrusion - TAPPI.org
In the extruder, cross-linking and chain scission reactions are dominating at low and high melt temperatures, respectively, for LDPE, and chain scission is over ...
[82]
What is Low-Density Polyethylene (LDPE)? - Xometry
Apr 29, 2022 · To make low-density polyethylene, you'll need to call on the radical polymerization process. This involves extreme heat (up to 570 degrees ...Settings · How Ldpe Is Made · Advantages And Disadvantages
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[PDF] Water Vapor Permeation in Plastics
For oxygen permeating a polymer above the glass temperature, the permeability increases approximately 10%/°C [DeLassus 2002, pg. 392]. Another thing that ...
[84]
https://www.pnnl.gov/main/publications/external/technical_reports/PNNL-26070.pdf
[85]
https://www.professionalplastics.com/professionalplastics/ElectricalPropertiesofPlastics.pdf
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[PDF] Photo-oxidation and weathering of LDPE studied by surface and ...
Sep 23, 2012 · Neat PE lost nearly 50% of its tensile strength after 7 months of outdoor weathering in Florida, whereas with HALS stabilization, the same 50%.
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https://depositonce.tu-berlin.de/bitstreams/e1312e3e-0e47-4a30-b93d-0676635cdfdb/download
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https://doi.org/10.1016/j.enconman.2009.12.017
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Low Density Polyethylene Market - LDPE - Industry Analysis & Size
Sep 26, 2025 · By end-user industry, packaging retained 58.45% of low density polyethylene market size in 2024, while healthcare and pharmaceuticals are poised ...
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Low-density Polyethylene Packaging (LDPE) Market Size
The global low-density polyethylene packaging market was valued at USD 20.8 billion in 2024, with a volume of 18,342.2 kilo tons, and is estimated to grow at a ...
[91]
Low Density Polyethylene (LDPE) Cost Intelligence Report, 2030
The LDPE category is expected to grow at a CAGR of 4.63% from 2023 to 2030. The increasing demand for films and shrink-wrap packaging in the food and ...Missing: percentage | Show results with:percentage
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Low Density Polyethylene | Plastic Film Distributor - PolymerFilms
It is known to be a material that has good clarity, excellent chemical resistance, good moisture barriers, and is often chosen because of its ease of processing ...
[93]
Polyethylene Film - an overview | ScienceDirect Topics
LDPE film is heat sealable, chemically inert, odour free and shrinks when heated. It has low water vapour permeability but high gas permeability.
[94]
Light Density Polyethylene (LDPE) Bottles Market
May 8, 2025 · In 2025, the Light Density Polyethylene (LDPE) Bottles Market is estimated at USD 1.0 million, and is projected to reach USD 1.7 million by 2035 ...
[95]
Squeeze Bottle Market Size & Share 2024-2034
Jun 18, 2024 · Polyethylene, in particular, is expected to dominate the market in 2024, capturing a projected market share of 63%. Such a boosted popularity ...Missing: LDPE | Show results with:LDPE
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Low-Density Polyethylene (LDPE) Solutions - Port Plastics
Moisture Resistance: LDPE is inherently moisture-resistant, making it an excellent barrier against liquids, which is crucial for packaging and storage solutions ...
[97]
Good Elasticity Expanded Polyethylene Foam Sheet , Thermal ...
Expansion Ratio: 3~40 Times. Width: 1m~1.8m. Thermal Conductivity: 0.032W/mk. High Light: heat insulation foam. ,. closed cell foam insulation roll. Expanded ...
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Expanded Polyethylene Foam (EPE)
Aug 25, 2020 · Expanded polyethylene foam, also known as EPE, is a molded semi-rigid, non-crosslinked, closed-cell polyethylene foam that is often denser and stronger.
[99]
Enhancement in Electrical and Thermal Properties of LDPE ... - NIH
Apr 13, 2022 · The thermal conductivity of the pure LDPE was 0.32 W/(m·K). The thermal conductivity of nanocomposite films doping with single-doped (h-BN) and ...
[100]
DOW™ HFDK-4201 EC Crosslinkable Power Cable Insulation ...
Unfilled, crosslinkable, low density polyethylene insulation compound designed for medium voltage power cable insulation applications. It has a low level of ...
[101]
ENDURANCE™ HFDA-9217 BK Compound for Cable Systems - Dow
Black, low-density polyethylene compound that provides high curing speed, good thermal stability and good weather resistance designed for area power ...
[102]
Medical-Grade Plastics – The Future of Healthcare - Techmer PM
Both high-density (HDPE) and low-density (LDPE) variants are used in tubing, containers, and prosthetics. PE is flexible, durable, and resistant to moisture ...
[103]
https://www.techmerpm.com/medical-grade-plastics-the-future-of-healthcare/
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Plastic Material Selection For The Medical Industry - First Mold
May 29, 2025 · Low-density polyethylene (LDPE) is a flexible and relatively cheap plastic used in squeeze bottles, tubing, and medical bags. High-density ...
[105]
Smooth LDPE Geomembrane Liners: Applications, Pros, Cons
May 5, 2025 · Smooth LDPE geomembranes are synthetic liners made from low-density polyethylene, known for their even surface texture. Unlike textured ...Missing: housewraps | Show results with:housewraps
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Polyethylene Sheeting, Construction Agricultural Film, MA
Construction film is typically made from polyethylene, a thermoplastic polymer known for its strength, flexibility, and resistance to moisture. The material may ...
[107]
Analysis and Design of Low-density Polyethylene Greenhouse Films
Aug 6, 2025 · Low-density polyethylene (LDPE) films are the most widely used plastic covering materials of greenhouses in Mediterranean Europe.
[108]
Polymer Pyramid: Choose the Best 3D Printing Material - 3devo
Oct 4, 2024 · Low-Density Polyethylene (LDPE): A flexible material with impact resistance, LDPE is used in applications like bottle caps and plastic bags.
[109]
LDPE Polymer - A Complete Guide to Low Density Polyethylene!
Jan 5, 2024 · LDPE is a versatile, thermoplastic polymer made from ethylene, known for its flexibility and ductility, and is used in many applications.<|separator|>
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Low Density Polyethylene (LDPE) Market Size & Share Trends, 2033
The packaging industry accounted for over 12.5 million metric tons, representing approximately 50 percent of total consumption. Asia-Pacific led production and ...
[111]
Interactive adverse effects of low-density polyethylene microplastics ...
LDPE-MPs contributed the maximum inhibition rates of 85%, 51.3%, 21.49 ... The concentration of microplastics (MPs) in the ocean is increasing at an ...
[112]
Microplastics in coastal and marine environments: A critical issue of ...
Among marine debris, 60–80 % consists of plastic, with 80 % of the debris originating from land, resulting in an estimated 51 trillion pieces of microplastics ...
[113]
Marine litter plastics and microplastics and their toxic chemicals ...
Apr 18, 2018 · Persistent plastics, with an estimated lifetime for degradation of hundreds of years in marine conditions, can break up into micro- and nanoplastics over ...
[114]
Production of methane and ethylene from plastic in the environment
Aug 1, 2018 · The emissions of hydrocarbon gases were measured using virgin LDPE pellets exposed for seven days to the full solar spectrum (FULL; 280–700 nm) ...Missing: life | Show results with:life
[115]
Low Density Polyethylene Market Size, Share and Forecast 2035
The global Low-Density Polyethylene (LDPE) market stood at approximately 22.6 million tonnes in 2024 and is anticipated to grow at a healthy CAGR of 3.39% ...
[116]
How Are Seabirds Impacted by Ocean Plastic, and What Can You ...
scientists estimate that 90 percent of seabirds have ingested plastic ...
[117]
Investigation on the effect of several parameters involved in the ...
Feb 20, 2024 · This work investigates the biodegradation of polyethylene (PE) and low-density polyethylene (LDPE) and the leaching of their harmful additives.
[118]
Understanding recycling symbols - Recycle Now
3 - PVC, used for car parts, window fittings, etc: Not easily recyclable. 4 - LDPE, used for plastic bags and wrapping, etc: Recycle at specialist points. 5 ...The On-Pack Recycling Label... · Other Symbols · Plastic Resin Codes
[119]
Mechanical and Thermal Degradation-Related Performance of ...
Oct 10, 2024 · This paper presents research aimed at laboratory experiments on static and cyclic fatigue testing of low-density polyethylene (LDPE) recovered from post- ...
[120]
Mechanical and Thermal Properties of Mixed PE Fractions from Post ...
Dec 1, 2022 · Degradation of Polyethylene during Extrusion. II. Degradation of Low ... The results show that simulated recycling did not significantly change ...
[121]
Mechanical Recycling of Packaging Plastics: A Review
Sep 30, 2020 · The sharp reduction in the properties of the material is due to deterioration thermo-oxidative and thermo-mechanical degradation of the chains ...2 Plastic Waste Recycling · 2.4 Polymer Blends In... · 4.1 PolyethylenesMissing: retention | Show results with:retention
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How the Global Plastic Recycling Industry Is Changing in 2025
Sep 20, 2025 · Recycling Rates Still Lagging. Globally, less than 10% of all plastic ever produced has been recycled. In 2024, global plastic waste generation ...Missing: 5.7% 2016 15%
[123]
Life cycle environmental impacts of chemical recycling via pyrolysis ...
May 15, 2021 · The results suggest that chemical recycling via pyrolysis has a 50% lower climate change impact and life cycle energy use than the energy recovery option.
[124]
Braskem's biopolymers avoid emissions of over 5 million tons of ...
Dec 7, 2020 · In 2010, Braskem announced the commissioning of the plant with production capacity 9of 200 kta becoming the world's leading biopolymer producer.
[125]
Climate and biodiversity impacts of low-density polyethylene ...
Jul 15, 2023 · According to the Plastics Europe (2014), 3.43 MJ of electricity is needed to produce 1 kg of LDPE and 0.25 MJ of heat can be exported from the ...
[126]
Ink Effects on LDPE Recycling: A Comprehensive Study
May 21, 2024 · This study delves into the effects of ink components on LDPE recyclates, focusing on thermal behavior and recycling impacts.
[127]
Recent trends in microbial and enzymatic plastic degradation
Aug 12, 2024 · This review accentuates the pivotal role of enzymatic and microbial degradation in mitigating plastic pollution, the associated challenges, and ...
[128]
Plastic waste and recycling in the EU: facts and figures | Topics
Jun 25, 2024 · It includes banning certain single-use plastic items and a 25% target for recycled content in plastic bottles by 2025 and 30% by 2030. The ...