Smartphone-activated anti-counterfeiting via HDPE/poly(3-bromothiophene)-encapsulated FAPbBr3 perovskite nanocomposites

Polymer nanocomposite can be produced through combination of organic polymer matrix with dispersed inorganic nanofillers. In this study, fluoromica was employed as inorganic nano filler to reinforce high density polyethylene (HDPE) matrix. Optimum nano filler loading to improve mechanical properties of the HDPE nanocomposite was investigated. The fluoromica was first surface modified through ion exchange method using dimethyldioctadecylammonium chloride (DODMAC) to obtain organically modified fluoromica (organo-fluoromica) with hydrophobic surface characteristic. The organo-fluoromica was incorporated into HDPE matrix in 0, 1, 2 and 4 wt%, melt mixed using twin screw extruder and compressed into sheets. The resultant HDPE/organo-fluoromica nanocomposites were subjected to the mechanical tests (tensile and tear tests). Results indicate that the HDPE nanocomposites with 2wt% of organo-fluoromica (HDPEOF2) possesses the highest tensile strength which is 23.72 MPa. The value is ∼15% higher than the neat HDPE. This was due to the good interactions between the organo-fluoromica nanofiller with the HDPE matrix. The surface modification produced hydrophobic nano filler for improving its compatibility with the hydrophobic HDPE matrix. Accordingly, elongation at break of the nanocomposite reduced while the Young’s modulus increased. This was caused by the restricted molecular motion of the HDPE chains as a result of nanofiller-matrix interactions. Findings also indicate that the use of nanofiller greater than 2wt% decreases the mechanical properties of the HDPE due to filler-filler interaction and therefore reducing the contact surface between the clay and the polymer matrix. Furthermore, the stiffness of the HDPE nanocomposite increased as concentration of nanofiller increased. The result of tear test follows the trend of tensile test, where the HDPE nanocomposite with 2wt% organo-fluoromica shows the best tear property. The tear strength of HDPEOF2 nanocomposites is found to be increased by 8.14% when benchmarked with the neat HDPE. This may be due to nanometric dispersion of the silicate layers and enhancement in nanofiller-matrix interactions that can improve the tearing resistance of the HDPE. The findings of this study revealed the potential of organo-fluoromica as reinforcing filler in the HDPE nanocomposite system, thus demand further research and development in this particular area.

The mechanical and adhesive properties of electrically and thermally conductive polymeric composites based on high density polyethylene filled with nickel powder

Processing and mechanical properties of carbon nanotube–alumina hybrid reinforced high density polyethylene composites

Short vegetal-fiber reinforced HDPE—A study of electron-beam radiation treatment effects on mechanical and morphological properties

The influence of sawdust particles reinforcement on the physical and mechanical characteristics of high-density polyethylene (HDPE) matrix composites was studied for application as sustainable wood plastic composites (WPCs) for housing. The WPCs developed by compression moulding method were characterised. The results revealed web-like structures/cross-linking in the microstructure of the samples, which is a characteristic of polymers. The microstructure revealed a good dispersion of sawdust particles and compatibilizer in the HDPE matrix and bonding, which enhanced the properties of the composites. The control sample C exhibited water absorption of 0.22 % whereas sample S8 having 1.1 to 1.4 mm sawdust particles, 30 wt. % of sawdust particles content, and 3 wt. % of compatibilizer exhibited the least water absorption of 0.14 %. The unreinforced HDPE control sample exhibited a tensile strength of 12.53 MPa while sample S7 with the smallest size (less than 1 mm) and 30 wt. % of sawdust particles content, and 7 wt. % of compatibilizer exhibited the highest tensile strength of 16.22 MPa. This is 29.5 % higher than that of the control sample. The control sample exhibited a flexural strength of 10.2 MPa while sample S7 exhibited the highest flexural strength of 14.85 MPa, which is 45.6 % higher than that of the control sample. The control sample exhibited a hardness value of 13.93 HV while sample S7 exhibited the highest hardness value of 19.17 HV, which is 37.6 % greater than that of the control sample. Samples S5, S7, S8, and S9, which contained high content of sawdust particles demonstrated impact energy values of 34.27, 33.14, 35.17, and 36.46 J respectively. The unreinforced control sample demonstrated a low wear rate value of 0.35 g/Nm. However, sample 7 demonstrated the least wear rate of 0.23 g/Nm, which is 34.3 % lower than that of the control sample. In view of these characteristics, the composites especially sample 7, has the potentials for application as a sustainable building material.

This work provides a study about the incorporation of a high density polyethylene (HDPE) matrix composite in medium density fiberboards (MDF). A composite was processed in a single screw extruder with 5% of Pinus spp fibers in a HDPE matrix and applied as reinforcing agent in MDFs, as well as pure HDPE, in 11 different variations, using 12% of urea-formaldehyde resin and nominal density of 750 kg.m−3. The composite and the pure HDPE were analyzed by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The DSC results showed that both polymeric matrix and composite presented the same melting temperature but the composite had a reduced melting enthalpy and crystallinity due to thermal history. SEM analysis showed a well distribution of fibers on the composite. The results of technological properties of MDFs were compared to commercial MDF standards. The MDF reinforced with 40% of polymeric composite reached all minimum standard requirements, being the most recommended to be used as an alternative to conventional MDF, in terms of physical and mechanical performance.

The focus of this research work is to study the effect of hybrid fillers of bamboo fiber and commercial glass fiber on high density polyethylene (HDPE) matrix without interfacial coupling agent. The hybrid composite was formed through melt blending method using two-roll mixing mill at temperature of 160 oC and was shaped using compression molding machine. The highest value of Tensile Modulus at break and Hardness were obtained at hybrid ratio of 70 % of HDPE/ 15 % bamboo/ 15 % glass particles (H/B15/G15). However, the inclusion of the hybrid fillers did not show any significant difference in Impact strength from the molded blank HDPE samples (H/B0/G0) while the percentage water absorbed by the samples predominantly decreased as the content of the commercial glass filler was increase in the HDPE matrix.

Blends of a high density polyethylene (HDPE) matrix and a polycarbonate (PC) minor phase were investigated through their morphology, heat resistance, mechanical properties, crystallizing behavior, rheological measurement and especially the compatible effect of a compatibilizer: low density polyethylene grafted diallyl bisphenol A ether (LDPE‐g‐DBAE). The blends without compatibilizer exhibited a phase growth and no adhesive between the HDPE matrix and the dispersed phase. In the presence of 10% by weight of LDPE‐g‐DBAE as a compatibilizer, more fine particles and a dim phase interface were observed, and the blends showed a remarkable increase in heat distortion temperature and mechanical properties. The compatibilized blends possessed a high apparent viscosity as compared with the noncompatibilized ones. However, the apparent viscosity of the blends, with or without the compatibilizer, was lower than that of the neat HDPE and PC. Exploration by DSC found that the melting point and the crystallinity of HDPE in the blends decreased, and especially for the blends with the compatibilizer. These facts could be interpreted in terms of the efficient compatible effect of the LDPE‐g‐DBAE, which resulted from the interaction between the diallyl bisphenol A ether unit of LDPE‐g‐DBAE and polycarbonate, and the miscibility of the LDPE unit and HDPE.

Mechanical behavior of glass microballoon (GMB) reinforced high density polyethylene (HDPE) matrix syntactic foams is investigated under tensile mode. GMB’s are blended in HDPE using brabender and subsequently compression molded to form the syntactic foam sheets. GMBs with true particle density 200 kg/m3 are varied by 0, 20, 40 and 60 vol. % in HDPE matrix. With increase in microballoon content modulus is increases while strength decreases. Syntactic foams present lower fracture strain as compared to neat HDPE. Compression molded neat HDPE exhibited higher modulus and lower strength as compared to injection molded samples. Micrography is performed using scanning electron microscope for all the tested samples

Thermal switching between solid- and liquid-like behavior of dispersed semi-crystalline telechelics and nanohybrids tailored for temperature-induced healing of polyethylene cracks

In this study, the alkali treatment of sawdust using different concentration of sodium hydroxide (NaOH) is performed. The purpose of this treatment is to improve the filler-matrix compatibility, thus, enhance the properties of tested specimens under various strain rate condition. The outcome shows the alkali treated sawdust did improve its surface roughness through reduction of sawdust diameter. With this increasing of surface roughness, it will enhance the compatibility between sawdust filler and HDPE matrix. For comparison purpose, the treated and untreated sawdust filler were reinforce in High Density Polyethylene (HDPE) matrix and have been test under static and dynamic loading using Universal Testing Machine (UTM) and Split Hopkinson Pressure Bar (SHPB) apparatus. The results indicate that the stiffness and compression strength properties were improved on treated sawdust composites for both static and dynamic loading compare to untreated sawdust composites.

Designers actively pursue the use of novel materials and concepts in furniture and interior design. By providing insights into their processing behavior and suitability for 3D-printing processes, this research helps to highlight the potential of using waste materials to create more environmentally friendly and sustainable 3D-printing filaments that can be used in furniture and interior design. Furthermore, the study evaluates the effect of incorporating palm midrib nanoparticles (DPFNPs) to reinforce a high-density polyethylene (HDPE) matrix with different loadings such as 10, 20, 30, 40, and 50 wt.%. The composites were extruded into filaments using a manual extruder, which was then utilized to fabricate 3D-printed specimens using a 3D-printing pen. The effect of adding DPFNPs on the composite's chemical, thermal, and mechanical properties was evaluated, with a particular focus on how these modifications influence the melt flow rate (MFR) and, subsequently, the material's printability. The results revealed that HDPE and filament composites presented similar FTIR spectra. On the other hand, the filament composites presented an increase in the thermal stability and a decrease in the mechanical strength with increasing DPFNP content in the HDPE matrix. The filaments were successfully printed using a 3D-printing pen. Thus, using DPFNPs in the HDPE matrix presents a low-cost alternative for filament production and may expand 3D-printing applications in interior and furniture design with more sustainable materials. Future work will delve into optimizing these composites for improved printability and assessing their recyclability, aiming to broaden their applications in 3D printing and beyond.

In this study, tailored polyethylene reactor blends with the in situ embedding of a weakly entangled ultra-high-molecular-weight polyethylene (UHMWPE) were synthesized by the polyhedral oligomeric silsesquioxane modified Ziegler–Natta (ZN) catalysts using a two-stage cascade polymerization technique. Holistic improvement of strength/stiffness/toughness was realized by the common injection modeling owing to the enhanced formation of an orientated structure which was verified by the patterns of two-dimensional (2D) small-angle X-ray scattering and 2D wide-angle X-ray diffraction, as well as the fracture morphology. 30 wt % of the less entangled UHMWPE was successfully incorporated into the high-density polyethylene (HDPE) matrix to achieve a synchronously increased tensile strength (52.4 MPa, +97.7%), Young’s modulus (604.2 MPa, +43.6%), and impact resistance (74.4 kJ/m2, +675%), compared with those of the benchmarked HDPE. However, dissipation of a shish-kebab structure was pronounced in the depth direction of the HDPE spline reinforced with the disentangled UHMWPE. This dissipation was proved to partially sacrifice the strength and stiffness. Importantly, the impact strength is greatly enhanced (+140%) due to the cocrystallization effect of the disentangled linear UHMWPE chains with the HDPE matrix. The HDPE matrix reinforced with the weakly entangled UHMWPE presents wider gradient distribution and orientation degree distribution of oriented structures (including shish-kebab and stacked lamella) along the depth direction. Thus, the balance of strength/stiffness/toughness was synergistically improved with the wider gradient distribution of oriented structures. This in situ polymerization method with the weakly entangled UHMWPE offers a promising routine for achieving the high-performance polyethylene commodity.

The recycling of waste polyurethane (PU) using radiation-induced grafting was investigated. The grafting of waste PU onto a high-density polyethylene (HDPE) matrix was carried out using a radiation technique with maleic anhydride (MAH). HDPE pellets and PU powders were immersed in a MAH-acetone solution. Finally, the prepared mixtures were irradiated with an electron beam accelerator. The grafted composites were characterized by Fourier transformed infrared spectroscopy (FT-IR), surface morphology, and mechanical properties. To make a good composite, the improvement in compatibility between HDPE and PU is an important factor. Radiation-induced grafting increased interfacial adhesion between the PU domain and the HDPE matrix. When the absorbed dose was 75 kGy, the surface morphology of the irradiated PU/HDPE composite was nearly a smooth and single phase, and the elongation at break increased by approximately three times compared with that of non-irradiated PU/HDPE composite.

In this work, “green” composites made from High Density Polyethylene (HDPE) and natural fiber based date palm fiber have been prepared and studied. The effects of different loadings of date palm fibers (DPF) on the morphological, thermal and melt rheological properties of the composites have been investigated. Morphological investigation showed that the fibers were evenly dispersed in HDPE matrix at all DPF loadings. Additionally, the results of differential scanning calorimetry (DSC) analysis revealed that the addition of the DPF in the HDPE matrix has slightly increased the crystallization temperature (ΔT = ± 1.33 oC). However, the crystallinity index, Xc of the composites at all DPF loadings were lower than the neat HDPE. The decrease of Xc was approximately 10.5 – 14 %. Differential scanning calorimetry (DSC) analysis results revealed that the addition of the DPF into the HDPE matrix has increased the crystallization temperature. However, the crystallinity index of the composites at all DPF loadings were lower than the neat HDPE. In term of melt rheological analysis, the complex viscosity of the composites were all higher than the HDPE matrix and increased with the increase of DPF loadings, which was due to the restriction of the HDPE chain segment movements as the amount of DPF increased.