Effects Of Maleated Polyethylene Research Articles

High‐performance wood‐reinforced crosslinked high‐density polyethylene composites

AbstractThis paper presents a comprehensive investigation into the manufacturing of high‐performance wood‐crosslinked high‐density polyethylene composites (WxHDPEC). In particular, the effect of maleated polyethylene (MAPE) treatment and concentration (0–50 wt%) of maple wood fibers is investigated. The samples were produced via dry‐blending followed by compression molding and a set of characterization was performed including chemical, morphological, mechanical, thermal, and physical properties. The gel content was found to increase with increasing wood fiber content, while the surface modification significantly improved the tensile strength (11%), tensile modulus (298%), flexural strength (138%), and flexural modulus (81%). Thermal analyses also showed improved thermal stability and higher thermal resistance for the treated composites. Finally, the Shore D hardness increased by 11.0 (from 61.5 to 72.5) and 12.1 (from 61.5 to 73.6) points, while the Shore A hardness increased by 7.5 (from 91.5 to 99.0) and 8.1 (from 91.5 to 99.6) points for the untreated and treated composites, respectively. These improvements are attributed to effective adhesion between MAPE‐treated wood fibers and the xHDPE matrix. The findings not only advance our understanding of these complex materials but also provide alternatives for various applications from construction to automotive engineering.Highlights High‐performance wood‐reinforced crosslinked high‐density polyethylene was produced. The effect of maleated polyethylene (MAPE) treatment and maple wood fibers was studied. Higher crosslink density in MAPE‐treated wood‐xHDPE was obtained. Wood‐crosslinked high‐density polyethylene composites have better properties.

Sustainable Use of Coffee Husks For Reinforcing Polyethylene Composites

The utilization of the coffee husk fiber (CHF) from the coffee industry as a reinforcing filler in the preparation of a cost-effective thermoplastic based composite was explored in this study. The chemical composition and thermal properties of the CHF were investigated and compared with those of wood fiber (WF). CHF proved to be mainly composed of cellulose, hemicellulose and lignin, and exhibited similar thermal behavior to WF. High density polyethylene (HDPE) composites with CHF loadings of from 40 to 70% were prepared using melt processing and extrusion. The processing properties, mechanical behavior, water absorption and thermal performance of these composites were investigated. The effect of maleated polyethylene (MAPE) used as a coupling agent on the composite was explored. The experimental results showed that increasing the CHF loading in the HDPE matrix resulted in an increase in the modulus and thermal properties of the composites, but resulted in poor water resistance. The addition of a 4% MAPE significantly improved the interfacial behavior of the hydrophilic lignocellulosic fiber and the hydrophobic polymer matrix.

The role of nanoclay formations and wood fiber levels on central composite designed polyethylene composites

Central composite designed experiments are conducted to study the independent effects of maleated polyethylene, dicumyl peroxide and nanoclay in the forms of natural (Cloisite® Na+) and masterbatch (Nanoblend™ concentrates MB2001) on the mechanical properties of fiber reinforced PE composites with different fiber levels. The optimum values are predicted on the results of designed experiments and there are linear regressions between fiber content and their mechanical properties. The deposition and formation of nanoclay particles in PE composites are ascertained by scanning electron microscope and transmission electron microscope observations. Both natural nanoclay and MB2001 can be delaminated and even exfoliated in polarized PE matrix. As wood fiber is introduced, natural nanoclay particles (nanoclay-natural) are deposited on fiber surface even loaded in fiber lumens, but the nanoclay particles of MB2001 (nanoclay-concentrate) are mostly dispersed in the matrix. In addition, the different reinforcements between nanoclay-natural and nanoclay-concentrates are also investigated to find out the influence of particle formation on the quality of composite materials.

Effects of MAPE Modified on Physico-Mechanical Properties of Silvergrass Reinforced High Density Polyethylene Composites

In this study, silvergrass (SV) reinforced high density polyethylene (HDPE) composites (WPCs) were prepared by injection molding. The effects of maleated polyethylene (MAPE), slivergrass fibers content on the mechanical, Differential scanning calorimeter, morphologies of WPCs were investigated. It was found that the mechanical properties of the SV reinforced HDPE composites can be improved by MAPE treatment. The highest tensile strength and flexural strength of the composites can be reached with 40% and 50% SV contents at the fixed 8% MAPE respectively. The SV can be the nucleating agent with the addition of MAPE. SEM images of tensile fracture surfaces of treated composites demonstrated better fiber-matrix adhesion.

Effects of MAPE Treatments on Thermal Properties of Silvergrass Reinforced High Density Polyethylene Composites

In this study,silvergrass (SV) reinforced high density polyethylene (HDPE) composites (WPCs) were prepared by injection molding. The effects of maleated polyethylene (MAPE), Slivergrass fibers (SV) content on the thermal, crystalline properties of WPCs were investigated. It was found that compared with the untreated WPCs, the thermal stability of the composites after incorporation of MAPE was significantly improved. Moreover, the results show that with MAPE adding, SV was an effective heterogeneous nucleating agent.

Analysis of the Mechanical Properties of Rice Husk Reinforced Polyethylene Composites Using Experiments with Mixtures

In recent years, the use of agro-wastes, such as rice husk (RH), in the manufacture of thermoplastic composites to replace wood fibres has emerged as a promising field of interest. Linear medium density polyethylene (LMDPE) and ground rice husk (GRH) were used to manufacture composites. The D-optimal design routine in Design Expert software was used to select ten different blends with different percentages of RH, MDPE and compatibiliser, maleated polyethylene (MAPE) along with four replicate blends. RH was varied between 15 to 50 wt%, MAPE between 1 to 6 wt% and MDPE between 44 to 84 wt%. The effects of RH, MDPE and MAPE content on the mechanical properties of the manufactured composites were examined. The results show that tensile and flexural properties of the composites were improved, whereas, Charpy impact strength was decreased with increasing RH loading. The effect of MAPE on tensile strength and Charpy impact strength was significant, but its effect was negligible on tensile modulus, flexural strength and flexural modulus of the composites.

Phase structure and properties of poly(ethylene terephthalate)/high‐density polyethylene based on recycled materials

AbstractBlends based on recycled high density polyethylene (R‐HDPE) and recycled poly(ethylene terephthalate) (R‐PET) were made through reactive extrusion. The effects of maleated polyethylene (PE‐g‐MA), triblock copolymer of styrene and ethylene/butylene (SEBS), and 4,4′‐methylenedi(phenyl isocyanate) (MDI) on blend properties were studied. The 2% PE‐g‐MA improved the compatibility of R‐HDPE and R‐PET in all blends toughened by SEBS. For the R‐HDPE/R‐PET (70/30 w/w) blend toughened by SEBS, the dispersed PET domain size was significantly reduced with use of 2% PE‐g‐MA, and the impact strength of the resultant blend doubled. For blends with R‐PET matrix, all strengths were improved by adding MDI through extending the PET molecular chains. The crystalline behaviors of R‐HDPE and R‐PET in one‐phase rich systems influenced each other. The addition of PE‐g‐MA and SEBS consistently reduced the crystalline level (χc) of either the R‐PET or the R‐HDPE phase and lowered the crystallization peak temperature (Tc) of R‐PET. Further addition of MDI did not influence R‐HDPE crystallization behavior but lowered the χc of R‐PET in R‐PET rich blends. The thermal stability of R‐HDPE/R‐PET 70/30 and 50/50 (w/w) blends were improved by chain‐extension when 0.5% MDI was added. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Effect of Maleated Polyethylene on the Crystallization Behavior of LLDPE/Clay Nanocomposites

The crystallization behavior and microstructure of linear low density polyethylene (LLDPE)/modified montmorillonite (20A) composites containing maleic anhydride grafted polyethylene (MA-g-PE) were investigated by differential scanning calorimetry (DSC), X-ray diffraction (XRD), and transmission electron microscope (TEM). The dispersion of 20A in LLDPE matrix depended on the amount of MA-g-PE. The degree of super cooling reduced when 20A was introduced into LLDPE with MA-g-PE. The Avrami analysis shows that the nonisothermal crystallization process of the LLDPE/20A composites followed the Avrami equation with Avrami exponent value in the range of 2.75–3.97. The activation energies calculated by Kissinger method were 986 kJ/mol for LLDPE, 949 kJ/mol for PE-A5MA0, 1445 kJ/mol for PE-A5MA5, and 1581 kJ/mol for PE-A5MA20. The activity of nucleation of PE-A5MA0 was 0.75 but the values of the composites with MA-g-PE were in the range of 0.37–0.56. These behaviors can be interpreted by the fact that the loading of MA-g-PE in LLDPE/20A composites enhances the dispersion of clay in LLDPE matrix and the good dispersion of 20A affects the degree of super cooling and the nucleation activity of silicate.

Effect of Maleated Polyethylene on the Rheological Properties of LLDPE/Clay Nanocomposites

Linear low density polyethylene (LLDPE)/20A composites were prepared by adding a moderate amount of maleic anhydride grafted polyethylene (MA-g-PE). The dispersion of the modified montmorillonite (20A) in LLDPE matrix depended on the amount of MA-g-PE. When the content of MA-g-PE was higher than 15 wt %, the exfoliated nanocomposite was obtained. The nanocomposites of adding a MA-g-PE showed unusual rheological properties such as high shear thinning tendency and elastic property. These effects were confirmed by an oscillatory viscometer. The wavy melt fracture occurred at 8720 s−1 for the LLDPE/20A composite but occurred at 10500 s−1 for LLDPE/20A composites containing 15 wt % MA-g-PE. The MA-g-PE modified LLDPE/clay composite could be less sensitive to melt fracture because the composite has a high elastic property to resist elongational stress when leaving the die.

Polymer‐Clay Nanocomposites Based on Blends of Polyamide‐6 and Polyethylene

AbstractThe preparation of polyamide‐6/clay, high‐density polyethylene/clay, and high‐density polyethylene/ polyamide‐6/clay nanocomposites is considered. X‐ray diffraction (XRD), differential scanning calorimetry (DSC), and Fourier Transform Infrared (FTIR) measurements show that the clay enhances the crystallization of the γ‐form of polyamide‐6. The clay also acts as a nucleation agent and causes a reduction of spherulitte size. Scanning electron microscopy (SEM) analysis of fracture surfaces shows that the clay reduces the PA‐6 particle size in the HDPE/PA‐6/clay nanocomposites and changes the morphology. Mechanical properties and the effect of maleated polyethylene are also reported.