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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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering 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 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]

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]

Purpose: This study aims to develop a biodegradable linear low-density polyethylene (LLDPE)/starch blends with improved mechanical and flow characteristics and evaluate the probability of using essential oils such as Moringa oleifira and castor oils as green plasticizers and compatibilizers to avoid using harmful chemicals. Design/methodology/approach: Corn starch was blended with LLDPE through the melt blending technique. The corn starch content was varied from 5 to 40 phr in LLDPE. To enhance poor mechanical characteristic of the LLDPE/starch, essential oils such as M. oleifira and castor oils were incorporated into the composites with different concentrations starting from 1 to 7 phr. The essential oils' effect on mechanical, flow character, thermal stability and electrical properties of the LLDPE/starch was also investigated. The morphology of LLDPE/starch containing essential oils was also investigated by scanning electron microscope (SEM). Findings: The results revealed that increasing the corn starch content had an adverse effect on mechanical and flow characteristics of the composites, whereas incorporation of essential oils had increased the flow and mechanical characteristics of the composites. Also, dielectric measurements revealed that permittivity and dielectric loss increased by increasing oil content. Moreover, the values of the blends containing castor oil are higher compared to that containing M. oleifira. The SEM micrographs illustrated that the presence of essential oils in LLDPE/starch enhanced the distribution and the homogeneity of the composites, and the particle size of starch granules became smaller in LLDPE matrix. Originality/value: This study aims to introduce green plasticizer and compatibilizer to avoid using harmful chemicals in packaging industry. [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]

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]

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]

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]

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]

Composite substrates of linear low-density polyethylene with thermotropic liquid crystals as inclusions with three different weight fractions were synthesized. The dielectric characterizations of the composites in X band frequencies were studied to assess their applicability as substrates for microwave devices. Thermotropic liquid crystals, NN-(terephthalylidene)bis(4-n-butylaniline), NN-(terephthalylidene)bis(4-n-hexylaniline) and NN-(terephthalylidene)bis(4-n-decylbenzamine) were synthesized in the laboratory at room temperature. Structural characterization for synthesized thermotropic liquid crystals was done using nuclear magnetic resonance and Fourier transform infrared spectroscopy. To confirm the distribution of liquid crystal inclusions in the polymer matrix, scanning electron microscope images were used. Water absorbance test was carried out following Archimedes' principle. The real part of complex permittivity and the dielectric loss tangent at X band frequencies for all the weight fractions of the composite were found to be ~ 2.1–2.4 and ~ 10−2–10−4 respectively. The magnetic loss tangent was also measured for the substrates and showed values within the range of 10−1–10−2. To establish the suitability of the fabricated substrates for use in antennas, the return losses were calculated using the complex permittivity and permeability values. [ABSTRACT FROM AUTHOR]

The incorporation of antimicrobial agents into packaging materials is an effective method to inhibit the microbial population and aimed at specific microorganisms to provide better and safe products. The present study aims at developing an effective antimicrobial film with silver ions as an antimicrobial agent with and without ethylene-vinyl acetate (EVA). In the present work, two different masterbatches (MBs) were prepared. In the first case MB of 90%, linear low-density polyethylene (LLDPE) and 10% silver ions as an antimicrobial agent were prepared. In the second case MB of 80%, LLDPE, 10% silver ion, and 10% EVA were prepared. An antimicrobial film with low-density polyethylene and different percentages of the MB (0–30%) was prepared and tested under Japanese Industrial Standard (JIS Z 2801:2000) for Escherichia coli bacteria and Staphylococcus aureus bacteria. With the increase in the percentage loading of MB, the living amount of bacteria decreases. The decrease in the living amount of bacteria was greater when EVA was incorporated. [ABSTRACT FROM AUTHOR]

We investigated the rheological behavior of linear low-density polyethylene (LLDPE)/polylactic acid (PLA) blends in the presence of modified and non-modified silica nanoparticles in extensional flow. Characterization methods were used as Fourier transform infrared spectroscopy, scanning electron microscopy, and rheometric measurements under shear and uniaxial extensional flows. The rheology behavior of LLDPE significantly was changed by the addition of PLA and silica nanoparticles. Extensional results showed that the elongational viscosity of the blends intensified by the incorporation of silica nanoparticles. Strain hardening was observed for LLDPE containing 2 wt.% of the unmodified silica nanoparticles, which disappeared by enhancement of the unmodified silica from 2 to 8 wt.%. Furthermore, elongation thinning was observed for the filled blends at high loading, which was more sensitive to the strain rate by increasing of PLA. Surface modification of silica was demonstrated in different elongational behavior. Indeed, a fracture took place by loading the modified silica nanoparticles in LLDPE; however, the intensity of this behavior dramatically increased for filled blends with a high loading of modified silica. [ABSTRACT FROM AUTHOR]

Rheological, molecular, thermal, and mechanical properties of binary blends based on bimodal high-density polyethylene (HDPE; ethylene–1-hexene copolymer) and unimodal linear low-density polyethylene (LLDPE; ethylene–1-butene–1-hexene terpolymer) were studied. Six blends with different HDPE/LLDPE weight ratios, 80/20, 70/30, 60/40, 50/50, 40/60, and 20/80, were prepared by blending in a double-worm extruder. The correlation of the rheological properties of the blends, analyzed by the capillary and rotation methods, with the melt flow index and molecular characteristics was demonstrated. LLDPE with increased flowability (MFI = 3 g/10 min) as a polymer additive is an effective plasticizer allowing control of the melt viscosity in a wide range and choice of the optimum target value of the melt flow index of the blend. The activation energy of the melt flow was calculated, and the relationship between this quantity and the content of short-chain branchings in polyethylene blends was revealed. The blends obtained are homogeneous, but an increase in the content of LLDPE in HDPE leads to a change in the polyethylene structure, which is confirmed by a decrease in the crystallinity and in the lamella thickness. The strength values at the yield point and at break decrease with an increase in the fraction of LLDPE in HDPE. Changes in the properties of these blends in their processing into a film by flat-die extrusion were studied. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystals (CNCs) were surface modified with 3-isocyanatopropyl triethoxysilane (ICPTS) in tetrahydrofuran at 62–63 °C using triethylamine as a catalyst. ICPTS modified CNCs were further studied as a nanofiller in nanocomposites with linear low-density poly(ethylene) (LLDPE) prepared by melt processing. The modification of CNCs was confirmed by FTIR, solid state NMR, and thermogravimetric analysis. Compared to unmodified CNCs, the ICPTS modified CNCs show enhanced compatibility with LLDPE as shown by SEM. Nanocomposites processed at 70 °C reveal slightly enhanced mechanical properties and this effect was further intensified by increasing the molding temperature up to 120 °C. Under such conditions, a 20% increase in Young's modulus and 30% increase in tensile strength are achieved compared to neat LLDPE. Differential scanning calorimetry confirms the degree of LLDPE crystallinity, beside the CNC reinforcing network formation, as an important decisive factor in defining the final mechanical properties of LLDPE/CNC nanocomposites. The maximal enhancement of mechanical properties was observed at rather low amount of added ICPTS modified CNC (1–2 wt.%), which is important for practical application as CNCs are still rather expensive nanofiller. By modification of CNC with ICPTS the CNC polarity is reduced, which result in their improved compatibility with LLDPE, while on the other hand they function as a plasticizer and thus reduce the LLDPE crystallization degree, especially at high CNC concentrations. [ABSTRACT FROM AUTHOR]

Polyamide 6 (PA6) is a polymer largely applied in the packing industry; however, it has limitations like high water absorption, notch-sensitive impact and high electrical resistance. Some strategies have been developed aiming to improve these drawbacks, as blending PA6 with other polymers, like linear low-density polyethylene (LLDPE) which is also an electrical insulator. In this work, antistatic packages for the transportation and storage of electronic devices were prepared by mixing PA6 and LLDPE with the addition of carbon black as an antistatic agent to reduce the electrical resistivity of polymers. PA6/LLDPE (50/50) blend-based carbon black composites with different contents of carbon black (5, 10 and 15 wt%) were prepared in a twin screw extruder, and their mechanical, rheological, electrical and permeation properties were studied. Thereby, the effects of the addition of maleic anhydride-grafted LLDPE (LLDPE-g-MA) in the composites were also studied. The addition of LLDPE-g-MA and 5 wt% and 10 wt% of carbon black in the PA6/LLDPE blend resulted in a 130 and 150% increase in impact strength, respectively. Adding 10 wt% of carbon black in the PA6/LLDPE/LLDPE-g-MA blend increased the elastic modulus, reduced the electrical resistivity by 14 decades and also reduced the water vapor permeability, allowing this material to be eligible for use as antistatic packaging. [ABSTRACT FROM AUTHOR]

Linear low density polyethylene (LLDPE) exhibits a complex molecular structure that is characterized by molar mass and chemical composition distributions. Both molecular parameters complementarily influence the final application properties. Typically, the molecular structure of commercial polyolefins is characterized by a set of technical parameters including the melt flow index, the crystallization and melting temperatures and the comonomer content as obtained using Fourier transform infrared or NMR spectroscopy. LLDPEs with high comonomer contents are typically regarded as plastomers or elastomers. Due to their low crystallinities, characterization of these materials using crystallization‐based analytical techniques is of limited use since the majority of the material is rather amorphous. Such materials need specific alternative analytical methods that may be based on molar mass and/or chemical composition fractionation. Here it is shown that for a comprehensive analysis of LLDPEs with similar bulk properties, preparative molar mass fractionation (pMMF) and advanced analysis of the fractions are required. The pMMF fractions are comprehensively analyzed using size exclusion chromatography, differential scanning calorimetry and high‐temperature high‐performance liquid chromatography to provide detailed information on molar mass and copolymer composition. Correlated information of these molecular parameters is obtained by comprehensive two‐dimensional liquid chromatography. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Thermal and mechanical properties of neat linear low-density polyethylene (LLDPE) hybrid biocomposite with sugarcane bagasse and eggshell as a reinforcing filler were investigated. Hybrid biocomposites with sugarcane bagasse/eggshell was varied in the range of 6/4, 12/8, 17/13, 20/20, 13/17, 8/12, and 4/6 wt.%, were prepared and examined. The sugarcane bagasse fiber (Sb) was surface-treated using a silane coupling agent (3-(trimethoxysilyl) propyl methacrylate) and eggshell (Es) was treated using titanium (IV) isopropoxide. The results showed that high calcium oxide content was 99% by weight in eggshell and silicon dioxide content was 50% by weight in sugarcane bagasse. The tensile and flexural modulus and hardness of the composites with treated Sb/Es were higher than that of the untreated. These values of the LLDPE/Sb/Es composites increased with Sb/Es content. Differential scanning calorimetry (DSC) results show interesting trends in term of the influence of Sb/Es content, both with untreated and treated Sb/Es on the crystallization behavior of the composites but the melting and cold crystallization temperature of its composites did not obviously change. Thermogravimetric analysis (TGA) indicated their thermal stability of the composites, both untreated and surface-treated Sb/Es were lower than that of neat LLDPE. The sample molded from the biocomposite with surface-treated Sb/Es particles showed better dispersion of the materials inside. [ABSTRACT FROM AUTHOR]

This work aims to develop green linear low-density polyethylene (LLDPE) composites that are commercially viable due to the low cost of the date palm leaflet filler, which is a local renewable resource. The filler was naturally treated with gum arabic solution. FT-IR, XRD, and SEM techniques were used to characterize the samples. The thermal and mechanical properties were measured by TGA, DSC, and tensile testing. The results showed noticeable changes in the properties of the composites compared to those of the original LLDPE sample. TGA revealed TGA revealed that the composite started thermally. The composites started thermally degrading before the original polymer, owing to the degradation of the natural components in the filler. The findings from DSC suggested that the crystallinity was affected. The tensile testing results indicated that the composites were appropriate for applications requiring low tensile strength at break and high Young's modulus. A comparison of these results with earlier ones exhibited that the basic additives in the polymer may have an effect on the filler performance. [ABSTRACT FROM AUTHOR]

In the current study, huntite and hydromagnesite (HH) was used as flame-retardant additive in linear low-density polyethylene (LLDPE). The effect of HH amount on the flame-retardant and mechanical properties of the composites was investigated. The compatibilizer (ethylene butyl acrylate) use and the surface modifications with stearic acid and silane coupling agent were used in order to improve the mechanical properties of the composites. The mechanical properties of the composites were studied using tensile test and dynamic mechanical analysis. The fire-retardant properties of the composites were investigated using limiting oxygen index (LOI), mass loss calorimeter, vertical (UL 94 V) and horizontal (UL 94 HB) burning tests. According to the flammability test results, LOI value increased, horizontal burning rate reduced as the added amount of HH increased, whereas UL 94 V rating remained burn to clamp. According to the mechanical test results, the addition of HH reduced the tensile strength and elongation at break values and increased the elastic modulus and the β transition temperature of the LLDPE as the added amount increased. Only the compatibilizer use improved the flammability properties of the composites with improved tensile strength. Both stearic acid and silane modification merely increased the toughness of the composites. [ABSTRACT FROM AUTHOR]

Thermoplastics have been widely used in petroleum, chemical, construction, urban gathering and transportation systems due to their superior performance. This work focuses on the corrosive behaviors of linear low-density polyethylene (PE-LLD) and polypropylene (PP) against sulfuric acid, nitric acid, hydrochloric acid, sodium hydroxide and sodium chloride solution. The research results indicate that the impact strength of PP was found to show a loss rate of 23. 9 % after corrosion Ma 10 wt % NaOH solution for one week, whereas the loss rate for PE-LLD was 22. 6 % after corrosion in a 10 wt % HCl solution for two weeks. The effect of H2 SO4 solution with a concentration of 10 wt % on the melting enthalpy of PE-LLD was very noticeable, and the enthalpy value decreased by 54. 4 % after immersion corrosion for 6 weeks. [ABSTRACT FROM AUTHOR]

A new technique for production of high-pressure vessels from polymer-composite materials is suggested. The vessel has the form of a double-layer balloon, the internal layer of which is made from linear low-density polyethylene by rotational molding and the external layer of which is formed by winding of a reinforcing fiber impregnated with an oligomer on a polymer liner. The suggested technique for production of high-pressure vessels is compared to the other known techniques. [ABSTRACT FROM AUTHOR]