Search

This study uses a rotomolding procedure to produce hollow cubes made of linear low-density polyethylene (LLDPE) and coconut fibers (CF). The purpose is to investigate the effect of different CF content (0, 5, 12.5, and 20 wt%) and size (100 and 50 mesh) on composite properties. As the CF content rises, the density of all composites decreases due to an increase in material porosity, a result of poor adhesion between the fiber and LLDPE. Impact strength reduced as the content of CF increased, except for the composite with 5 wt% of CF and 50 mesh size. The ineffective adhesion between coir fibers and LLDPE, along with the presence of voids in the matrix, caused the mechanical properties to deteriorate as the CF content increased. The flammability test revealed that all samples dripped. The neat LLDPE sample deformed, whereas the LLDPE/CF composites maintained their shape. This behavior suggests that CF plays a structural role in burning composites. Maleic anhydride-grafted polyethylene (MAPE), calcium stearate, and magnesium stearate additives did not contribute to reducing the composite’s porosity. MAPE was the only additive that did not reduce the elastic modulus of composites. [ABSTRACT FROM AUTHOR]

A novel linear low‐density polyethylene containing H‐shape long‐chain‐branching structures (LCB‐LLDPE) is industrially synthesized with Ziegler‐Natta catalysts and gas‐phase polymerization process at the assistance of ω‐alkenylmethyldichlorosilane copolymerization‐hydrolysis chemistry. The incorporated LCB structures are characterized by NMR, SEC, and SAOS (small amplitude oscillatory shear) measurements. With a same‐sourced plain LLDPE as a comparison benchmark, the new LCB‐LLDPE is studied for its properties on various aspects, revealing, among others, significantly reinforced rheological properties, including enhanced shear‐thinning behavior, a significant strain‐hardening phenomenon in extensional flow, and substantially increased melt strength, as well as significantly improved optical properties, which all benefit its application in extrusion blow molding for thin‐film production. [ABSTRACT FROM AUTHOR]

[Display omitted] A series of sulfur-bridged bis(2-indenyl) zirconocenes were synthesized and tested for ethylene/1-octene co- polymerization and 1-decene oligomerization. Zirconocene bearing two 5,6-positioned methyl substituents in indenyl moieties, distant from the metal center, appeared to be an active catalyst producing 1-decene oligomers with high content of unsaturated vinylidene end groups, which is preferable for post-functionalization. [ABSTRACT FROM AUTHOR]

The developed polymer composites based on low-density linear polyethylene modified with OMCARB CH85 technical carbon have been experimentally investigated. A comprehensive analysis of the composites' properties has demonstrated that the use of this filler type results in a percolation transition at a 25 % mass fraction of filler, leading to an decrease in resistivity. Samples with lower concentrations exhibit electrical resistance values corresponding to those of semiconductors. When the filler concentration reaches 20 %, the maximum material stiffness is observed, and the character of stretching transitions from ductile to brittle. Electron microscopic examination of the samples reveals a mesh microstructure of the polymer matrix with embedded carbon black particles acting as crystallization nuclei. As a result, the mechanical properties and electrical conductivity of the composite are enhanced.

AbstractIn order to improve the mechanical properties of polymer composites, natural fibers are being employed more and more as reinforcements. However, incorporating natural fibers can be difficult in rotational molding, a process used to make hollow plastic objects like kayaks and fuel tanks. Bi-axial rotation is a procedure that can result in fiber aggregation and is challenging to regulate. The optimal combination of NaOH-treated peanut shell powder (TPSP) and linear low-density polyethylene (LLDPE) for rotational molding was examined in our research reported in the manuscript. Processability was assessed using a variety of testing techniques, such as Fourier transform infrared spectroscopy (FTIR), particle size distribution, bulk density, melt flow index (MFI), differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). Significant peaks with TPSP concentrations in LLDPE ranging from 10 to 22% were shown by the FTIR. Blends of TPSP with LLDPE containing more than 18% TPSP were not acceptable for rotational molding due to poor flowability, as shown by particle size and bulk density investigations and supported by MFI data. According to our study, a 16% TPSP blend was the best formulation for rotational molding since it improved the thermal stability and increased the crystallinity by around 10%. [ABSTRACT FROM AUTHOR]

The present study examines the influence of successive treatments on the fiber surface (NaOH, hydrogen peroxide, and acetic anhydride). The palm petiole fibers were incorporated as reinforcement in linear low-density polyethylene (LLDPE) composites with a loading of 15 wt% and evaluated for mechanical, morphological, and dynamic mechanical properties. The effect of treatments on fiber surfaces has been confirmed using FTIR. The scanning electron microscopy (SEM) results showed that the enhanced interfacial adhesion between the fibers and the matrix makes treated composites more rigid and homogeneous, which means that the fibers are distributed uniformly. The tensile modulus and flexural strength were all enhanced by adding 15% of untreated palm petiole fibers recorded at 598 MPa and 15.56 MPa, respectively, while the tensile strength was decreased. Palm-petiole fiber composites' storage modulus increased, and the acetylated-alkali fiber (FNA) reinforced LLDPE composite showed the highest storage modulus. Loss modulus increased when palm petiole fibers were strengthened. The Tan delta of composites made from palm petiole fibers was low initially but expanded with fiber addition. We concluded that successive treatments improve the performance of the palm petiole fiber residue and have the potential to create a new type of sustainable and eco-friendly material for various applications. [ABSTRACT FROM AUTHOR]

Linear low‐density polyethylene (LLDPE) is a polyolefin known for its superior low‐temperature heat seal ability, low‐temperature tolerance, and bag‐tear resistance which are important features for the polymeric packaging sector. In this work, to improve the mechanical properties and expand the range of applications of LLDPE, the microfibrillar clay mineral palygorskite (PAL) was added. However, the use of PAL as a reinforcing agent for polymers depends on its purification process to extract accessory minerals such as calcite, dolomite, and quartz. In addition to this purification process, two surface modifications were used on the purified PAL (PALp) to improve interactions with LLDPE: silanization with aminosilane (PALs) and organophilization by incorporating an organic compound (PALo). The PAL were characterized according to their morphological properties using transmission electron microscopy (TEM), X‐ray diffraction (XRD), and Fourier transform infrared spectroscopy (FT‐IR). The films of LLDPE/PAL, with varying levels (1, 3, and 5 wt%) and types of PAL (raw PAL, PALp, PALs, and PALo), were prepared by an extrusion process, and films were prepared by compression molding, without preferred orientation. The films were characterized by rheological analyses, tensile tests, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and water vapor permeability. Incorporating modified PAL was significant in enhancing the mechanical properties of the nanocomposites. LLDPE/PALs with the addition of 3 wt% PALs showed a 14% increase in elastic modulus (281.08 ± 8.25 MPa) compared to the nanocomposite with 3 wt% of raw PAL (243.43 ± 15.01 MPa). Highlights: The PAL is a clay mineral with a fibrous morphology and has a low cost.The technique to purify PAL is a quick, simple, and inexpensive technique.Comparison between of two technique surface modification of PAL.The effectiveness of modifications of PAL was confirmed in LLDPE films.The surface modification with silanization was more effective. [ABSTRACT FROM AUTHOR]

Graphene‐loaded thermoplastic nanocomposite films must be evaluated for antibacterial activity, mechanical, and barrier properties before being utilized as food packaging. Herein, economically feasible linear low‐density polyethylene (LLDPE)‐based flexible packaging materials were developed via the melt compounding technique at 170°C temperature by taking advantage of both graphene nanoplatelets (GNP) and nano zinc oxide (ZnO) fillers. Morphological studies reveal that in composites loaded with GNP/ZnO hybrid fillers, ZnO nanoparticles form a network‐like structure throughout the polymer matrix. Simultaneously, GNPs are uniformly dispersed. The inclusion of hybrid nanofiller considerably reduces both the oxygen transmission rate and the water vapor transmission rate (WVTR) in LLDPE nanocomposites. A maximum decrease of 36% and 67%, respectively, in both oxygen transmission rate and WVTR is observed for 3 wt% of hybrid filler loading in a thermoplastic matrix containing 1 wt% of nano ZnO. The antibacterial efficacy of the derived nanocomposite films is obvious against gram‐positive (Bacillus subtilis) and gram‐negative (Escherichia coli) bacterial strains. These nanocomposite films have the potential to be successfully utilized as flexible packaging materials owing to their improved thermal, barrier, and antibacterial effectiveness. Highlights: GNP/ZnO was used as a hybrid reinforcing filler in the LLDPE matrix.ZnO nanoparticles establish a network‐like morphology.LLDPE nanocomposite films exhibited excellent antibacterial activity.Oxygen and water vapor barrier properties were significantly improved.The thermoplastic composite films could be used as food packaging materials. [ABSTRACT FROM AUTHOR]

The reliability of thermal regulation systems is crucial for ensuring the stability of condensed-mode gas-phase fluidized bed reactors (FBRs) used in the production of linear low-density polyethylene (LLDPE). However, studies reporting on the practical industrial control engineering of such reactors relying on thermal equilibrium mechanisms are scarce. This study presents a thorough analysis of a hot thermoregulating water (TRW) valve-jamming incident and interprets the related phenomena and parameter changes. The effect of the catalyst activity and variations in the liquid-phase quantities on the TRW valve action are investigated in depth, and a general explanation is provided by analyzing typical distributed control system data trends and proven deductive reasoning. Results indicate that the polymerization stability is maintained by two thermal pathways. The first pathway is related to the latent (condensate)/sensible heat (gas) extraction and polymerization heat of the materials, and the second is associated with the TRW system, specifically the cold and hot TRW branches. These pathways exhibited synergistic bidirectional effects. Finally, a series of innovative measures are proposed for internal and external operations to fully prevent and respond to TRW valve malfunctions and maintain overall polymerization stability. This study enhances the dependability of linear low-density polyethylene production through advanced process optimization utilizing the Unipol prototype and offers perspectives on system engineering for polyethylene production processes. [ABSTRACT FROM AUTHOR]

The blending of polymers is an efficient means for developing new materials in a less hazardous and more economical way compared to the synthetic route. Polymers with different properties are blended to obtain a new material with combined properties. In this study, a thermoplastic elastomer blend is prepared by melt mixing a metallocene-based polyolefin elastomer (Engage 8003, abbreviated as EN) with linear low-density polyethylene (LLDPE, abbreviated as LL) using a twin-screw extruder in various compositions. To investigate the effect of the electron beam on the properties, LL, EN and their blends are irradiated in the 50–250 kGy dose range. The samples are subjected to gel fraction, mechanical, dynamic mechanical, hardness, heat shrinkability, volume resistivity and morphological studies. The % gel fraction, hardness and heat shrinkability of a sample increase with an increase in the irradiation dose. With increasing LL content, Young's modulus and ultimate tensile strength of the blends are increased, maintaining the % elongation at break in an attractive region. LE64 (60 wt% LL and 40 wt% EN) and LE46 (40 wt% LL and 60 wt% EN) blends show optimized mechanical and dynamic mechanical properties. Irradiation further increases the tensile strength and Young's modulus of LE64 up to 150 kGy and LE46 up to 200 kGy. The volume resistivity of the LE64 blend increases tenfold and quadruples for LE46 compared to non-irradiated blends when irradiated at 200 kGy. The morphological structures of the non-irradiated and crosslinked blends support the outcome of the obtained properties nicely. [ABSTRACT FROM AUTHOR]

Linear low-density polyethylene (LLDPE) is a type of plastic with a high percentage of solid waste and is hardly degradable. The characteristics of LLDPE such as high toughness and low density have the potential to be an alternative aggregate substitute for applications in non-structural mortar composites. The purpose of this study was to determine the suitable formulation of LLDPE aggregate substitution against silica sand for the application of non-structural adhesive mortar composites. Vinyl acetate/ethylene (VAE) surfactant (1.2 wt%) was used to improve the interface between LLDPE and the cement matrix. Mechanical testing; XRD and FTIR characterization; density measurements; compression, adhesion, and thermogravimetric test; and morphological observation were carried out in this experiment. The results showed that LLDPE substitution decreased physical properties and accelerated thermal degradation. Cracks occurred on higher amount of LLDPE composition due to big difference in polarity. Suitable LLDPE substitution composition for adhesive mortar is up to 50%. [ABSTRACT FROM AUTHOR]

The effect of electrically conductive carbon black on the electrophysical and mechanical properties of the linear low-density polyethylene has been experimentally investigated. The structural parameters of carbon black have been determined, which have a significant effect on the electrical conductivity of carbon black and the electrical conductivity of polymer composite materials when it is used as a filler. It is established that the introduction of 10–20 wt. % carbon black in linear low-density polyethylene provides high conductivity of composite materials, while increasing their modulus of elasticity, but at the same time reduces elongation at break. It is shown that, in general, the studied carbon black is a promising filler in the development of electrically conductive polymer composite materials for electrical and radio engineering purposes.

Linear low‐density polyethylene (LLDPE) combined with the piperazine pyrophosphate (PAPP) and melamine cyanurate (MCA) was adopted to prepare the flame retardant LLDPE composite by melt blending. The research results showed that the PAPP/MCA mixture with a mass ratio of 4:1 presented the optimal flame retardant effect. With the 25 wt% addition amount, the LLDPE composite passed the UL‐94 V‐0 level (1.6 mm), and the limiting oxygen index (LOI) reached 29.4%. The peak of heat release rate (PHRR) decreased by 78.9% from 877.5 to 185.0 kW/m2, which is attributed to the good synergistic effect between PAPP and MCA, forming the stable and compact char layer. Besides, the thermal behaviors were characterized through thermogravimetric (TG) analysis, and the synergistic mechanism was investigated by scanning electron microscopy (SEM), TG analysis‐infrared spectrometry (TG‐IR), and x‐ray photoelectron spectroscopy (XPS). The results indicate that the good synergistic flame retardant effect can enhance the flame retardancy of LLDPE materials, and with the addition of MCA and PAPP, a flame retardant LLDPE composite with good thermal stability and mechanical properties can be prepared with no molten droplets on combustion, which provides a feasible solution for the application of high‐performance halogen‐free flame retardant LLDPE materials. [ABSTRACT FROM AUTHOR]

Maleic anhydride-modified homopolymerized polypropylene (PP-g-MAH) and maleic anhydride-modified polyolefin elastomer (POE-g-MAH) were used as bulking agents to improve the poor processing and mechanical properties of highly filled composites due to high filler content. In this study, a series of linear low-density polyethylene (LLDPE)/magnesium hydroxide (MH) composites were prepared by the melt blending method, and the effects of the compatibilizer on the mechanical properties, flame retardancy, and rheological behavior of the composites were investigated. The addition of the compatibilizer decreased the limiting oxygen index (LOI) values of the composites, but they were all greater than 30.00%, which belonged to the flame retardant grade. Mechanical property tests showed that the addition of the compatibilizer significantly increased the tensile and impact strengths of the LLDPE/60MH (MH addition of 60 wt%) composites. Specifically, the addition of 5 wt% POE-g-MAH increased 154.07% and 415.47% compared to the LLDPE/60MH composites, respectively. The rotational rheology test showed that the addition of the compatibilizer could effectively improve the processing flow properties of the composites. However, due to the hydrocarbon structure of the compatibilizer, its flame retardant properties were adversely affected. This study provides a strategy that can improve the processing and mechanical properties of highly filled composites. [ABSTRACT FROM AUTHOR]

Linear low‐density polyethylene (LLDPE) and high‐density polyethylene (HDPE) are polyolefins widely used in the packaging sector. Seeking to improve the mechanical properties with good cost‐effectiveness, attapulgite (ATP) was chosen as a reinforcing filler for the polyolefins. ATP is a hydrated magnesium and aluminum clay mineral with a microfibrous morphology, and the purity of this filler depends on the deposit. ATP is associated with the presence of accessory minerals that need to be removed so as not to interfere with its final application. Thus, an ATP purification process was carried out through physical separation and chemical treatment with hydrogen peroxide (H2O2) and sulfuric acid (H2SO4). This purification process despite having a low yield and is very effective in reducing impurities and organic matter. This ATP was named ATPa. LLDPE/ATPa and HDPE/ATPa nanocomposites with the addition of 1, 3, and 5 wt% of ATPa were prepared by extrusion and hot pressing. The mechanical properties (Shore D hardness, tensile tests, and Izod impact strength), thermal properties (differential scanning calorimetry—DSC and thermogravimetric analysis—TGA), X‐ray diffraction, rheological, and transmission scanning microscopy (TEM) were determined for these nanocomposites. The mechanical properties of the nanocomposites increased with the addition of ATPa. HDPE/ATPa nanocomposites showed more promise than LLDPE/ATPa nanocomposites. The addition of 5 wt% ATPa increased the tensile strength by 14% for the HDPE matrix and 5% for the LLDPE matrix and increased the elastic modulus by 46% for HDPE and 26% for LLDPE. [ABSTRACT FROM AUTHOR]

The application of highly filled composites is limited by their poor processing and rheological properties due to the high loading of fillers. One possible solution to this problem is to use maleic anhydride grafted polypropylene (MAPP) with high melt index as compatibilizer and lubricant. Herein, magnesium hydroxide (MH)/linear low‐density polyethylene (LLDPE) composites with 60 wt% of MH were prepared using MAPP with three different melt flow indexes (MFI). The equilibrium torque and melt flow index tests show that the addition of MAPP with high MFI significantly improves the processability and flowability of MH/MAPP/LLDPE composites. The rheological studies show that it also leads to a substantial reduction in the viscosity and therefore MH/MAPP/LLDPE composites exhibit more solid‐like responses. The scanning electron microscopy shows that a transition layer is formed at the MH‐LLDPE interface. The flame retardancy test shows that the addition of MAPP slightly reduces the flame retardancy of the composites as evidenced by the reduced limiting oxygen index and increased total heat release. Cone calorimeter test shows that the simultaneous addition of MH and MAPP has a synergistic smoke suppression effect. [ABSTRACT FROM AUTHOR]

In this paper, the linear low-density polyethylene (LLDPE) fibers were used as the precursors to prepare low-cost carbon fibers (CFs) via ultraviolet crosslinking-vulcanized stabilization-carbonization processing. The spinning particles were obtained by mixing linear low-density polyethylene with photoinitiator 4-chlorobenzophenone (4-CBP), crosslinkers triallyl isocyanurate (TAIC), and thermal stabilizer antioxidant 1010, and then the ultraviolet (UV) photosensitive LLDPE fibers were fabricated by traditional melt spinning. Then, the LLDPE primary fibers were treated by UV irradiation, vulcanized stabilization and carbonization to obtain the low-cost CFs. to characterize the structure and properties of ultraviolet crosslinked polyethylene (UV-XLPE) fibers and CFs, the Fourier transform infrared spectrometer, differential scanning calorimeter, thermogravimetric analyzer, X-ray diffractometer and scanning electron microscope were adopted. The results showed that, UV irradiation introduced a crosslinked structure of LLDPE fibers, and the degree of gelation of XLPE fibers reached a maximum of 48.6% when UV irradiation was carried out for 15 min; with the extension of UV irradiation time, the melting temperature and crystallization temperature of UV-XLPE fibers move to the direction of low temperature, and the crystal size of the fiber decreases; after vulcanization, the carbon yield of the fiber is significantly improved, reaching up to 62.9%, and the surface and section of CFs are dense. [ABSTRACT FROM AUTHOR]

In this paper, we report that the compatibility of polymer blends between linear low-density polyethylene (LLDPE) and cyclic natural rubber (CNR) can be increased by the addition of oleic acid-grafted linear low-density polyethylene. The research aims to investigate the effect of LLDPE-g-OA compatibilizer in LLDPE/CNR blends on improving the mechanical properties and characteristics of the blends. The LLDPE/CNR/LLDPE-g-OA blends (compatible blends) were prepared by blending methods in the molten phase using an internal mixer set at a temperature of 160oC with a rotation speed of 100 rpm. The LLDPE pellets were inserted into it until melts and followed with an addition of CNR and LLDPE-g-OA. The tensile strength test results have shown an increase in mechanical properties after the addition of the compatibilizer with a maximum content of 4 wt%. The difference in FTIR spectra of compatible blends is indicated by the presence of C=C bonds from CNR, which appear at 1654.9 cm-1, indicating the occurrence of physical bonds in the blends. The existence of the LLDPE-g-OA compatibilizer has increased the thermal stability of the polymer blends and changes in the melting point temperature of 1240C. Compatible blends showed that the surface morphology was smoother, and there were significant microstructural changes compared to incompatible blends.

The need to reach carbon neutrality as soon as possible has made the use of recycled materials widespread. However, the treatment of artificial marble waste powder (AMWP) containing unsaturated polyester is a very challenging task. This task can be accomplished by converting AMWP into new plastic composites. Such conversion is a cost-effective and eco-friendly way to recycle industrial waste. However, the lack of mechanical strength in composites and the low filling content of AMWP have been major obstacles to its practical application in structural and technical buildings. In this study, a composite of AMWP/linear low-density polyethylene (LLDPE) filled with a 70 wt% AMWP content was fabricated using maleic anhydride-grafted polyethylene as a compatibilizer (MAPE). The mechanical strength of the prepared composites is excellent (tensile strength ~18.45 MPa, impact strength ~51.6 kJ/m2), making them appropriate as useful building materials. Additionally, laser particle size analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, and thermogravimetric analysis were used to examine the effects of maleic anhydride-grafted polyethylene on the mechanical properties of AMWP/LLDPE composites and its mechanism of action. Overall, this study offers a practical method for the low-cost recycling of industrial waste into high-performance composites. [ABSTRACT FROM AUTHOR]

The poor processing and rheological properties of highly filled composites caused by the high loading of fillers can be improved with the use of maleic anhydride grafted polyethylene wax (PEWM) as compatibilizer and lubricant. In this study, two PEWMs with different molecular weights were synthesized by melt grafting, and their compositions and grafting degrees were characterized by Fourier transform infrared (FTIR) spectroscopy and acid-base titration. Subsequently, magnesium hydroxide (MH)/linear low-density polyethylene (LLDPE) composites with 60 wt% of MH were prepared using polyethylene wax (PEW) and PEWM, respectively. The equilibrium torque and melt flow index tests indicate that the processability and fluidity of MH/MAPP/LLDPE composites are significantly improved with the addition of PEWM. The addition of PEWM with a lower molecular weight leads to a substantial reduction in viscosity. The mechanical properties are also increased. The limiting oxygen index (LOI) test and cone calorimeter test (CCT) show that both PEW and PEWM have adverse effects on flame retardancy. This study provides a strategy to simultaneously improve the processability and mechanical properties of highly filled composites. [ABSTRACT FROM AUTHOR]

Temperature is one of the key parameters to determine the structures and properties of polymers during processing, but the effect of processing temperature on similar-structured polymer blends has rarely been reported. In this work, a linear low-density polyethylene (LLDPE)/ethylene-octene copolymer (EOC) blend with similar-structured components was chosen as a model system to study the effect of processing temperature (including compounding temperature and molding temperature) on its crystallization, phase morphology, and tensile behavior. It was found that the blends presented evenly distributed rubbery domains at lower processing temperatures, whereas a special, EOC-rich phase domain consisting of a less stable crystalline phase and a rubbery phase was observed at higher processing temperatures. The phase morphology was mainly determined by the final processing temperature, which had a major effect on the yield stress of the material. This work not only reports novel results on processing-structure-performance relations of similar-structured blends but can also guide the design and production of LLDPE-based products with tailored properties. [ABSTRACT FROM AUTHOR]

Utilizing oxo-degradable additives is an alternate, efficient method of managing plastic trash. To prepare the polymer chain for microorganisms to break down the fragments over time, oxo-degradation of plastics involves breaking the chain into small pieces. In this study, a film with a thickness of 35 µm is created by mixing a mixture of linear low-density polyethylene (LLDPE) and d2w grade master batch (pro-oxidant). This thickness falls within the range of specifications for linear low-density polyethylene (LLDPE) films manufactured in petrochemical businesses. Additionally, is the study investigates how the mechanical characteristics of linear low-density polyethylene (LLDPE) are affected by the addition of a d2w pro-oxidant additive at five different weight percentages (0, 0.5, 1, 2, and 3% w/w). After thermal processing for films in an oven for one to seven days, the progress of LLDPE film is monitored by FTIR analysis to check for the presence of the carbonyl group by assessing the mechanical properties of the film. Tensile strength at break, tensile strength at yield, elongation at break, and elongation at yield are the mechanical qualities that are measured. Both the machine direction (MD) and the transverse direction (TD) are used to measure all properties. Following seven days of exposure to the oven at 70 °C, the mechanical properties of the film deteriorated. Both in the machine and transverse directions (MD and TD), the tensile strength at break dropped by 46.62% and 31.8%, respectively. Both in the machine and transverse directions (MD and TD), the tensile strength at yield dropped by 22% and 36.36%, respectively. Both machine and transverse elongation at break (MD and TD) were reduced by 21% and 38.36%, respectively. Following the addition of pro-oxidant and after thermo-oxidative treatment in an oven at 70 °C for 7 days, the results of the FTIR measurement for LLDPE did not significantly alter. [ABSTRACT FROM AUTHOR]

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In preparation of polymer nanocomposites, achieving good mixing and uniform distribution of nanofillers is highly desired for property enhancement. Polyethylene (PE) and its nanocomposite with halloysite nanotubes (HNTs) possesses a myriad of potentials for advanced engineering properties. A high nanoparticle loading is preferred to capitalize the nano‐reinforcement, thermal, and barrier properties. The capability of a two‐roll calendaring machine to disperse HNT particles into a linear low‐density polyethylene (LLDPE) matrix at elevated processing temperatures was assessed. Morphological, thermal, mechanical, and rheological behavior of prepared nanocomposites were characterized. A homogeneous distribution of HNTs in concentrations up to 5 wt.% was evidenced by SEM analysis. TGA showed the 10 wt.% composite exhibited an overall outstanding thermal stability. DSC analysis revealed the 30 wt.% sample has the highest Tm and Tc, and the %crystallinity did not change much due to HNT incorporation for all samples. DMA showed the storage and loss moduli increased with increase in HNT loadings. The effect of loading HNTs into the LLDPE matrix on Tg was minimal, implying that LLDPE and HNTs are quite compatible. The results demonstrated that the two‐roll mill fabrication method can efficiently keep HNT particles unagglomerated and disperse them evenly into the LLDPE matrix. [ABSTRACT FROM AUTHOR]

Composites made of linear low-density polyethylene (LLDPE) and β-cyclodextrin/d-limonene inclusion complex (CD-lim) were prepared by melt extrusion to develop a novel food packaging material. Scanning electron microscopy evidenced a fairly good dispersion of the filler within the polymeric matrix. Infrared spectroscopy coupled with thermogravimetric analysis confirmed the presence of CD-lim in the composites, proving that the applied technology of including the essential oil within β-CD cages allows for preventing a sizable loss of d-limonene despite a high temperature and shear applied upon extrusion processing. Moreover, the influence of the filler on the thermal properties of PE was assessed. It was found that the cyclodextrin-based inclusion complex significantly fastens the crystallization path of the polyethylene matrix with an improved crystallization rate of the PE/CD-lim composites compared to the neat polymer. [ABSTRACT FROM AUTHOR]

Blending polyethylene with thermoplastic polyolefin elastomers (TPOs) is a promising way to manipulate its structures and tailor its properties. Herein, three TPOs, i.e., two ethylene–octene copolymers (EOCs) and an olefin block copolymer (OBC) with different structures, were used to comparatively investigate the miscibility, crystallization, and phase behavior of their blends with a linear low-density polyethylene (LLDPE). It was found that large differences occurred in the crystallization and phase behaviors of the blends due to the different extent of similarity in the molecular structure between the TPO and the LLDPE matrix. In particular, a unique segregated phase morphology comprised a less stable crystalline phase and a rubbery phase was found in an LLDPE/EOC blend. The tensile performance and elasticity of the blends were also studied and correlated with the structures of the blends. This work not only provides novel results on the miscibility and phase behavior of the similar-structured LLDPE/TPO blends, but can also guide the design of LLDPE-based products with tailored performances. [ABSTRACT FROM AUTHOR]

In this paper, we report that the compatibility of polymer blends between linear lowdensity polyethylene (LLDPE) and cyclic natural rubber (CNR) can be increased by the addition of oleic acid-grafted linear low-density polyethylene. The research aims to investigate the effect of LLDPE-g-OA compatibilizer in LLDPE/CNR blends on improving the mechanical properties and characteristics of the blends. The LLDPE/CNR/LLDPE-g-OA blends (compatible blends) were prepared by blending methods in the molten phase using an internal mixer set at a temperature of 160 oC with a rotation speed of 100 rpm. The LLDPE pellets were inserted into it until melts and followed with an addition of CNR and LLDPE-g-OA. The tensile strength test results have shown an increase in mechanical properties after the addition of the compatibilizer with a maximum content of 4 wt%. The difference in FTIR spectra of compatible blends is indicated by the presence of C=C bonds from CNR, which appear at 1654.9 cm-1, indicating the occurrence of physical bonds in the blends. The existence of the LLDPE-g-OA compatibilizer has increased the thermal stability of the polymer blends and changes in the melting point temperature of 124 0C. Compatible blends showed that the surface morphology was smoother, and there were significant microstructural changes compared to incompatible blends. [ABSTRACT FROM AUTHOR]

Polymer blends have the potential to be developed into new resins for specific applications with balanced performance properties and economic advantages. In this paper, polypropylene (PP) and linear low-density polyethylene (LLDPE) blends were investigated at specific composition of PP/LLDPE (60/40) blends (PL40) using a Twin Screw Extruder (TSE). The nano-calcium carbonate (CaCO3) content was varied (between 0–40 wt %), and the composites were investigated using slit die rheometers. Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) techniques, revealed the existence of favorable interaction between the surface of CaCO3 nanoparticles and PL40 matrices after surface modification of aminopropyltriethoxy silane (AMPTES) coupling agent. Rheological properties reveal that both the apparent viscosity and the pseudo-plasticity of the PL40 nanocomposites increases with increasing nano-CaCO3 contents and decreases slightly by treated nano-CaCO3 with 2% AMPTES. Dynamic mechanical analysis (DMA) demonstrated that the storage modulus (G′) and glass transition temperature (Tg) are enhanced upon treated nano-CaCO3 with a coupling agent. The results from the mechanical properties exhibited that the impact strength was optimum at 20% nano-CaCO3 content, but tensile strength slightly decreased for untreated PL40 nanocomposites. However, treatment with amino coupling agent improved tensile strength. This attribute to the enhancement of dispersion of the nano-CaCO3 particles in PL40 matrix, leading to improved interfacial adhesion. Treatment of nano-CaCO3 significantly improved the Young's modulus and flexural modulus compared to the untreated PL40 composites. The crystallization behavior of the composites supported the strong interfaces formed on addition of the amino coupling agent. Furthermore, scanning electron microscopic (SEM) showed evidence of improvement in the dispersion of treated CaCO3 in the PL-40 matrix. [ABSTRACT FROM AUTHOR]

Plastic film has been widely used as one of the most important materials in various agricultural fields, due mainly to the chemical stability, thinness, and light properties. At the same time, the mechanical properties of plastic film can be the main research direction of film structure design in recent years. In this study, the experiment and numerical simulation were carried out for the damage analysis of plastic film under the hail impact. Among them, the air cannon test device was used to analyze the failure form and damage law of plastic film under hail impact. A high-speed camera and laser speed meter were then utilized to record the deformation process and energy absorption of plastic film that impacted by the ice ball. The finite element method (FEM) was also selected to evaluate the structural parameters of plastic film using ABAQUS software. The error analysis was performed on the failure area and the energy absorption of the plastic film, in order to verify the effectiveness of the numerical simulation. There was the relatively small error of the experimental and numerical simulation, indicating the better performance of the simulation. The plastic film under ice ball impact was also analyzed as follows. Firstly, the different sizes of the ice ball were selected to evaluate the impact angles of the ice ball impact plastic film. Secondly, the simulation was carried out in the the single and secondary impact of the ice ball impact on the plastic film. Finally, the ice ball impact plastic film was simulated with the different thicknesses and ice impacting double-layer plastic film with different distances between layers. The failure form and energy absorption of the plastic film were achieved in the better performance after numerical simulation. The following results were obtained: 1) The plastic film with the 0.12 mm thickness efficiently resisted the impact of hail with a diameter of less than 10 mm. Once the hail size was more than 30 mm, the plastic film was damaged rapidly, due to the action of the tensile stress wave. In addition, there was the larger damaged area that caused by the ellipsoidal hockey ball impact plastic film than that by the spherical one. 2) The secondary impact of the ice ball on the plastic film caused the superposition of stress waves, leading to the accelerated destruction of the film. 3) The largest damaged area of the film was observed, when the ice ball impact angle was 60° at the ice ball impact angle of 0°, 30° and 60°. 4) The damaged area of the double-layer film greatly increased with the increase of the distance between the plastic films. The anti-hail impact effect of the double-layer plastic film was better than that of the single-layer plastic film with the same thickness, when the distance between the double-layer plastic films was controlled within 5 mm. Therefore, the numerical simulation can be used to analyze the damage of plastic film under the impact of the ice ball. The tensile strength of plastic film can also be improved the better ability of hail impact resistance. This finding can provide a strong reference for the structural design and damage analysis of thin films. [ABSTRACT FROM AUTHOR]

In this article, nonpolar polyethylene with polar poly(vinyl chloride) is considered as a polymer–polymer mixture. Direct mixing of poly(vinyl chloride) and polyolefins leads to the formation of incompatible mixtures that have weak complex properties. To form this mixture, chlorinated polyethylene and a copolymer of polyvinyl chloride with polyethylene were used as compatibilizers. An extreme relationship of the elastic modulus on the composition of the blend at a PE content (5–20 wt.%) was revealed. The use of EBM model representations made it possible to identify the reasons for this relationship, namely, the cumulative contribution of structural changes in PVC and the enhancement of interfacial adhesion due to the presence of a compatibilizer at the phase boundary. [ABSTRACT FROM AUTHOR]

Abstract Herein different stabilizer formulations of linear low‐density polyethylene (LLDPE) against UV‐ and heat‐initiated degradation are described. The project aims at outdoor applications, such as irrigation piping and profiles, in the Middle East desert regions, where long‐term weathering stability due to high temperatures and solar radiation is important. Two UV/heat formulations, without and with carbon black (CB) as pigment, were incorporated into LLDPE by melt compounding. Neat LLDPE and the stabilized compounds were exposed to accelerated UV and heat aging. Morphological analysis through scanning electron microscopy of the UV‐exposed neat LLDPE showed more severe surface cracking compared to the CB‐containing LLDPE, while all stabilized compounds did not show any surface degradation. Crack formation was less visible for the thermally aged samples. A significant decrease in molecular weight (MW) was observed for the neat UV‐exposed LLDPE, while both unpigmented stabilized compounds showed little change in MW. Mechanical properties, thermal analysis, and carbonyl index results supported the morphological results, which confirmed that CB alone was slightly more effective in protecting the LLDPE against UV initiated degradation, but performed worse against thermal initiated degradation. UV1 and UV2 compounds were efficient against both UV‐ and heat‐initiated degradation, with UV1 performing better for unpigmented compounds, and UV2 for the pigmented ones.

[Display omitted] • CHO ternary diagram targets were used to initialize Aspen Plus simulation for steam co-gasification of glycerol and LLDPE. • A 50 % LLDPE content produced a syngas yield of 3.22 Nm3/kg at SFR of 1. • A carbon conversion efficiency of 95% was achieved at a 50% LLDPE and SFR of 0.8. • A syngas lower heating value of 11.63 MJ/Nm3 was achieved at 50 % LLDPE and SFR of 0.8. • Cold gas efficiency of 64% was achieved at 50% LLDPE content and SFR of 0.8. The co-gasification of different wastes for syngas production is a promising technology as it reduces pressure on waste management and promotes waste valorization. This paper considered the steam co-gasification of glycerol and linear low density polyethylene plastic (LLDPE) waste to produce syngas. To achieve this, a graphical targeting approach based on carbon, hydrogen, oxygen (CHO) ternary diagrams was used to determine the impact of different operating parameters (pressure, temperature and LLDPE content) on syngas composition. It was determined that an increase in pressure decreased H 2 and CO content but increased the content of CH 4 , CO 2 and H 2 O. It was also determined that increasing the LLDPE content increased H 2 and CH 4 concentration, but decreased CO, CO 2 and H 2 O concentration. The synergistic interaction of the feedstocks on the syngas ratio and lower heating value (LHV) was also determined. Results revealed that increasing the pressure decreased the synergistic effect. Furthermore, an Aspen Plus simulation was performed at different steam to feedstock ratios (SFR) and at 1000 K and 1 bar. The highest positive extent of synergy in terms of LHV, syngas yield (SY), carbon conversion efficiency (CCE) and cold gas efficiency (CGE) of 8.29 %, 21.51 %, 23.38 % and 23.81 % was achieved at LLDPE content of 50 % and SFR of 0.8, 1, 0.8 and 0.8 respectively. At these operating conditions the value of LHV, SY, CCE and CGE was found to 11.63 MJ/Nm3, 3.22 Nm3/kg, 95 % and 64 % respectively. [ABSTRACT FROM AUTHOR]

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ultra‐high molecular weight polyethylene (UHMWPE) and linear low‐density polyethylene (LLDPE) with different ratios were melt‐blended in an internal mixer. Results of rheological tests and scanning electron microscopy indicate that the blends are well miscible in the range of small addition amount of UHMWPE. The content of UHMWPE is suggested to be less than 5.0 wt%, to guarantee good compatibility of biphasic blends. Differential scanning calorimetry studies indicate that co‐crystallization occurs between UHMWPE and LLDPE. The crystallinity increases with the increase of UHMWPE as a nucleating agent. As a result, an improvement in mechanical properties is achieved. When the addition amount of UHMWPE is 5.0 wt%, the impact strength, breaking elongation, Young's modulus, and tensile strength are significantly increased by 27%, 25%, 75%, and 21% respectively. [ABSTRACT FROM AUTHOR]

Attapulgite (ATP) is a low-cost hydrated clay mineral of aluminum and magnesium and can be used for the preparation of linear low-density polyethylene (LLDPE) nanocomposites. However, the ATP contains accessory minerals that can harm their performance and hinder their polymer interaction. Then, a purification process of this clay mineral is necessary to raise the interactions between ATP and LLDPE. Furthermore, the non-polar nature of LLDPE can also hinder these interactions. One way to improve these interactions is the surface modification of ATP. In this way, the ATP was modified using aminosilane (3-aminopropyl) triethoxysilane (APTES). Raw ATP (ATPr), purified ATP (ATPp), and silanized ATP (ATPs) were characterized, and LLDPE/ATP nanocomposites with 3 and 5 wt% of ATPr, ATPp, and ATPs were prepared by extrusion. The nanocomposites were characterized by scanning electron microscopy (SEM), mechanical properties (tensile tests, Shore D hardness, and impact strength), and X-ray diffraction. APTES was grafted onto the clay surface. The APTES did not modify the crystal structure of ATP and, in addition, it improved the mechanical properties of LLDPE/ATPs nanocomposites. The addition of 5 wt% of ATPs increases the tensile strength, elastic modulus, and Shore D hardness, in addition to improving the dispersion of nanoclay in the polymer matrix. [ABSTRACT FROM AUTHOR]

Polymer-modified bitumen binders have been dramatically used over the last decade to combat the increasing weight and volume of heavy vehicle traffic and to reduce the pavement maintenance cost. This paper provides the findings of a study performed to evaluate new polymer composites to be used in bitumen modification. The proposed polymer is an Elastomer–Plastomer Vulcanised (EPV) nanocomposite containing low-density polyethylene (LLDPE), styrene butadiene rubber and a type of nanoclay and a small amount of bitumen binder. An example of bitumen binder was modified with 2%, 4%, and 6% of different EPV types and the storage stability and morphology of modified binders were evaluated to select the optimum EPV type. Further rheological analyses were conducted on modified binders containing 2%, 4%, and 6% of the selected EPV. It has been found that modification of bitumen with 4% of the selected EPV resulted in increasing the stiffness and elastic properties at the range of intermediate to high in-service temperatures. The viscosity of modified binders also increased at elevated production temperatures. [ABSTRACT FROM AUTHOR]

Utilizing oxo-degradable additives is an alternate, efficient method of managing plastic trash. To prepare the polymer chain for microorganisms to break down the fragments over time, oxo-degradation of plastics involves breaking the chain into small pieces. In this study, a film with a thickness of 35 µm is created by mixing a mixture of linear low-density polyethylene (LLDPE) and d2w grade master batch (pro-oxidant). This thickness falls within the range of specifications for linear low-density polyethylene (LLDPE) films manufactured in petrochemical businesses. Additionally, is the study investigates how the mechanical characteristics of linear low-density polyethylene (LLDPE) are affected by the addition of a d2w pro-oxidant additive at five different weight percentages (0, 0.5, 1, 2, and 3% w/w). After thermal processing for films in an oven for one to seven days, the progress of LLDPE film is monitored by FTIR analysis to check for the presence of the carbonyl group by assessing the mechanical properties of the film. Tensile strength at break, tensile strength at yield, elongation at break, and elongation at yield are the mechanical qualities that are measured. Both the machine direction (MD) and the transverse direction (TD) are used to measure all properties. Following seven days of exposure to the oven at 70 °C, the mechanical properties of the film deteriorated. Both in the machine and transverse directions (MD and TD), the tensile strength at break dropped by 46.62% and 31.8%, respectively. Both in the machine and transverse directions (MD and TD), the tensile strength at yield dropped by 22% and 36.36%, respectively. Both machine and transverse elongation at break (MD and TD) were reduced by 21% and 38.36%, respectively. Following the addition of pro-oxidant and after thermo-oxidative treatment in an oven at 70 °C for 7 days, the results of the FTIR measurement for LLDPE did not significantly alter.

Differential scanning calorimetry (DSC) and thermo-gravimetric analysis (TGA) were performed to evaluate the influence of olive pomace flour (OPF) and a coupling agent (C) on linear low-density polyethylene (LLDPE) bio-composites. The glass transition temperature (Tg), melting temperature (Tm), enthalpy of fusion (ΔHm), crystallization temperature (Tcryst.), heat of crystallization (ΔHcryst,) and percent crystallinity (Xc) were extracted from the DSC results. The degradation behavior was extracted from the TGA. Tg value (–114 °C) was unaffected by the addition of both OPF and C. A sharp DSC Tm peak, around 125 °C, was observed with its position being dependent on both filler and C contents. The ΔHm for the filler at 40% content decreased slightly, from 132 J/g for 0% filler to 123 J/g. TGA showed that the thermal degradation of LLDPE in the composite became easier upon increasing the OPF filler and coupling agent. [ABSTRACT FROM AUTHOR]

Composites made of linear low-density polyethylene (LLDPE) and β-cyclodextrin/d-limonene inclusion complex (CD-lim) were prepared by melt extrusion to develop a novel food packaging material. Scanning electron microscopy evidenced a fairly good dispersion of the filler within the polymeric matrix. Infrared spectroscopy coupled with thermogravimetric analysis confirmed the presence of CD-lim in the composites, proving that the applied technology of including the essential oil within β-CD cages allows for preventing a sizable loss of d-limonene despite a high temperature and shear applied upon extrusion processing. Moreover, the influence of the filler on the thermal properties of PE was assessed. It was found that the cyclodextrin-based inclusion complex significantly fastens the crystallization path of the polyethylene matrix with an improved crystallization rate of the PE/CD-lim composites compared to the neat polymer.

Linear low‐density polyethylene (LLDPE) 7042, which has a butene comonomer, is widely used but has poor tear and dart strengths. For practical applications, small amounts of other materials can be blended with 7042 to effectively improve its properties. In this study, four blend resins and films (cast and compressed films) were prepared by blending 7042 with four LLDPEs (2045G, 9030, 23F, and 9085) in 8:2 ratios. The results indicated that after blending 2045G, 23F, or 9030 with 7042, the crystallization ability of the three blends was significantly suppressed and crystal size decreased. Moreover, the molecular chain can pass though more lamellar stacks in the blends, leading to an increased tie‐chain concentration. Therefore, the tear and dart impact strength of the blend films improved. In contrast, the crystallization ability of the 7042/9085 blend was only slightly suppressed and did not significantly impact its properties. These findings contribute to our understanding of the relationship between material structures and properties, demonstrating that LLDPE blends can be used to improve the tear and dart strengths of 7042. [ABSTRACT FROM AUTHOR]

Herein different stabilizer formulations of linear low-density polyethylene (LLDPE) against UV- and heat-initiated degradation are described. The project aims at outdoor applications, such as irrigation piping and profiles, in the Middle East desert regions, where long-term weathering stability due to high temperatures and solar radiation is important. Two UV/heat formulations, without and with carbon black (CB) as pigment, were incorporated into LLDPE by melt compounding. Neat LLDPE and the stabilized compounds were exposed to accelerated UV and heat aging. Morphological analysis through scanning electron microscopy of the UV-exposed neat LLDPE showed more severe surface cracking compared to the CB-containing LLDPE, while all stabilized compounds did not show any surface degradation. Crack formation was less visible for the thermally aged samples. A significant decrease in molecular weight (MW) was observed for the neat UV-exposed LLDPE, while both unpigmented stabilized compounds showed little change in MW.Mechanical properties, thermal analysis, and carbonyl index results supported the morphological results, which confirmed that CB alone was slightly more effective in protecting the LLDPE againstUV initiated degradation, but performed worse against thermal initiated degradation. UV1 and UV2 compounds were efficient against both UV- and heat-initiated degradation, with UV1 performing better for unpigmented compounds, and UV2 for the pigmented ones. [ABSTRACT FROM AUTHOR]

LLDPE can be effectively converted into small molecules below C4 under mild condition using H-ZSM-5 catalyst and a small amount of water, achieving a selectivity of 100%. [Display omitted] • Linear low-density polyethylene can be potently thermolyzed into C1-C4 compounds. • The selectivity for C1-C4 compounds is 100%. • The thermal degradation reaction under a relatively low temperature of 220 °C. • The density of Brønsted acid sites is crucial for LLDPE decomposition. • Water enhances bond breakage and oxygenated product formation on Brønsted acid. The escalating environmental issues resulting from waste plastic necessitate innovative decomposition methods that optimize conversion rates and product selectivity. In this study, we demonstrate that linear low-density polyethylene (LLDPE) can be effectively hydrothermolyzed into C1 − C4 compounds with a selectivity of 100 % in the presence of trace water on H-ZSM-5 catalyst under a relatively low temperature of 220 °C. Water plays a dual role here as both a solvent and a reactant. It was found the density of Brønsted acid sites is crucial for LLDPE decomposition, serving as the primary active centers for cracking LLDPE chains. In-situ EPR studies indicate a synergistic mechanism of free radical and carbenium ion pathways in LLDPE depolymerization. Density Functional Theory (DFT) simulations show that the depolymerization starts with the cleavage of a C–C bond in polyethylene, instigated by a hydrogen radical from the Brønsted acid site, leading to various intermediate stages for the formation of tert -butanol, acetone and acetic acid from two potential pathways. The presence of water is crucial in these pathways, aiding bond breakages and the creation of oxygenated products in the Brønsted acid site. This study represents a substantial leap forward in sustainable methodologies for upcycling plastic waste. [ABSTRACT FROM AUTHOR]

Experience of structure development, manufacture, and testing of a pneumatic pressure shell accumulator with a volume of 25 dm3 is presented. A binder composition for "cold" hardening based on ÉD-20 epoxy resin and Étal-23X cycloaliphatic amine is developed. In terms of rheological and physicomechanical properties the binder proposed is suitable for manufacturing shells by a "wet" winding method with low energy consumption for hardening. [ABSTRACT FROM AUTHOR]

Doing experiments in order to determine mechanical properties of nanocomposites costs a lot. Therefore, finding the ways by which the properties of the nanocomposites can be predicted without any empirical or few number of empirical experiments seems to be useful. In the present study, efforts have been made to create a relation between mathematical model based on dimensionless number (Ch) and mechanical properties of low-density polyethylene/linear low-density polyethylene/styrene ethylene butadiene styrene (LDPE/LLDPE/SEBS) nanocomposite reinforced by nanoparticles of calcium carbonate. The proposed model is able to predict mechanical properties of nanocomposites based on their composition. This model is capable to predict elongation at break in terms of Young's modulus and fracture toughness, and to predict fracture toughness in terms of Young's modulus and elongation at break. The results showed prediction of the dimensionless number Ch model, and the experimental results are consistent. [ABSTRACT FROM AUTHOR]

Substitution of synthetic polymers by polymers prepared from renewable resources as well as synthetic fibers by natural fibers is a current research topic. They target various sectors of application such as the automotive industry, transport, packaging, building, and so on, that can offer a solution of lightness, great performance, and a minimum impact on the environment. In the present study, biocomposites based on linear low-density polyethylene (LLDPE) reinforced with nonchemically treated and noncompatibilized almond shell powder (ASP) particles were prepared by an elaboration process based on mixing polymer powder with ASP particles having similar density in solid state. For consolidation, thermocompression technique has been used. The mass ratio of ASP in the LLDPE/ASP composites varied from 10 wt% to 40 wt%. Effects of ASP wt% on the mechanical and structural properties of biocomposites have been explored through tensile and shore D hardness tests as well as microscopic observations. Homogenous repartition of ASP particles in the polymer matrix was observed for less than 20 wt% ASP. For more than 20 wt% ASP, agglomeration of fillers particles has been observed. Also, it has been found that elastic modulus of the biocomposites increases with ASP particles wt%, while tensile strength and ductility decrease when the ASP wt% increases. [ABSTRACT FROM AUTHOR]

The banded to sheaf‐like morphology transition of linear low‐density polyethylene spherulites in the micron‐thick film was investigated systematically for the first time. It was confirmed that this transition predominantly resulted from the thickening long period and the weakening surface stress of the multilamellar crystals as the crystallization temperature was increased. The mechanism might be different from the confinement effect of the ultrathin film. Moreover, based on the high‐selectivity of combinatorial method, a series of unique spherulitic crystals, such as double‐nested, multiple‐nested and hollow spherulites, were successfully constructed, which might provide a potential application in model substrate and surface modification studies. [ABSTRACT FROM AUTHOR]