Plastic Blends Research Articles

Co-pyrolysis and hydrogenation of Thar coal, waste plastic and waste oil blends for fuel oil production

ABSTRACTCo-liquefaction of Thar coal with waste plastic and waste oil was carried out to get high-quality fuel from waste. Four major variables, temperature, residence time, hydrogen pressure and coal: waste plastic ratio, oil: coal and oil: waste plastic ratios were investigated. According to results, maximum oil yield was obtained at 400°C temperature, 100psi pressure, 60 min residence time, and oil: coal: waste plastic ratios of 6:2:2. An FTIR result and 13C NMR analysis have shown extracted oil contains almost 84% aliphatic compounds and 16% aromatic compounds. Among aliphatic, there is more %age of diesel fraction. Extracted residue can also be used as a fuel in cement industry and in power generation plants because it contains almost 83–84% carbon with less than 1% sulfur.

Effect of exhaust gas recirculation on a CRDI engine fueled with waste plastic oil blend

The inevitable rise in the usage of plastic poses a serious threat to the environment owing to their non-biodegradable nature. The lack of proper infrastructure for treating and recycling plastic wastes give rise to the disposal problem. However, the oil synthesized from these waste plastics can be used as an alternative fuel for C.I engines which not only helps to tackle the disposal problem but also aids in recovering precious energy from these wastes. This experimental investigation aims to study the effects of plastic-diesel blend(P30) fuel on the performance, emission and combustion characteristics of a twin cylinder CRDI engine operating at different EGR rates (0%, 10% & 20%). The experimental results showed a slight drop in the engine performance while operating with plastic blend, mainly overall due to its higher viscosity and lower heating value. The vast upsurge of NOX emissions with plastic blend was mitigated by the aid of EGR methodology. Marginal increase in the discharge of regulated emissions like HC, CO and soot were noticed for both plastic blend as well as EGR operations. The experiments were carried out for five different loading conditions varying from 0% to 80% in steps of 20% each and found out that waste plastic-diesel blend can be successfully used as an alternative fuel in diesel vehicles without any prior modifications in the engine.

Highly conducting blend hybrid electrolytes based on amine ended block copolymers and organosilane with in-situ formed silica particles for lithium-ion batteries

In this study, amine ended block co-polymers of ethylene oxide/propylene oxide units are reacted separately with poly(ethylene glycol) diglycidyl ether (PEGDGE) and (3-isocyanatopropyl)triethoxysilane (ICPTES) and then mixed in different weight ratios to obtain ion conductive and mechanically stable hybrid solid polymer electrolytes (SPEs). Various characterization techniques are employed to explore the morphology, thermal stability, molecular interaction, backbone structure and dynamic behavior of the blend hybrid SPEs. The hybrid SPE exhibits the maximum ionic conductivity of 1.1 × 10−4 S cm−1 at 30 °C. The electrochemical stability window of hybrid SPEs varies from 4.5 to 4.7 V, depending on salt concentration. Moreover, the “salt free” hybrid membrane is plasticized in an organic electrolyte solvent to enhance the ionic conductivity to an exceptionally high value of 2.4 × 10−2 S cm−1 at 30 °C and 1.8 × 10−1 S cm−1 at 70 °C. The test cell consists of plasticized blend hybrid membrane delivers an initial discharge capacity of 142.5 mAh g−1 and retains 92% of initial capacity after 70 cycles with coulombic efficiency value of over 99%. Our results show that the blend hybrid electrolytes can be a promising electrolyte system for applications in high energy density lithium-ion batteries.

Solid state 13C‐NMR study of a plasticized PLA/PHB polymer blend

ABSTRACTHigh‐resolution solid‐state 13C nuclear magnetic resonance spectra and 13C spin–lattice relaxation times T1(13C) are used to characterize the structure of a polymer blend prepared from poly(lactic acid) (85 wt %) and poly(3‐hydroxybutyrate) (15 wt %) and the effect of the plasticizer triacetine on the structure and molecular dynamics of the blend. Single‐pulse and cross‐polarization magic angle spinning 13C nuclear magnetic resonance spectra indicate that the nonplasticized polymer blend consists of semicrystalline poly(3‐hydroxybutyrate) domains built into an amorphous poly(lactic acid) matrix. Triacetine supports formation of the crystalline regions within both polymer components in the blend. Spin–lattice relaxation times of carbonyl carbons indicate that the nonplasticized polymer blend consists of noninteracting chains of blended polymers and plasticization of the polymer blend increases the relaxation rate. The glass transition, cold crystallization, and melting processes of the nonplasticized and plasticized blends were also studied using differential scanning calorimetry methods. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46296.

Characterisation of wood plastic composite manufactured from kenaf fibre reinforced recycled-unused plastic blend

This paper presents the development of wood plastic composite manufactured from recycled polypropylene/polyethylene (r-PP/PE) blend reinforced with kenaf fibre. The r-PP/PE were sourced from rejected-unused diapers, which the plastic and absorbent gel were separated. The composite was prepared by varying the fibre loadings, at 0, 30, 40, 50, and 60 wt%. The composite was tested for flexural and impact tests followed by thermal and morphological analyses. The thermal analysis was performed by using differential scanning calorimetry technique, while the scanning electron microscopy was used for morphological analysis. It was found that the maximum flexural strength of the composite was at 30 wt% of kenaf fibre, meanwhile the maximum modulus was at 60 wt%. SEM morphology showed the failure mode from the impact fractures such as voids, fibre breakage and matrix cracking. From thermal analysis, the addition of kenaf fibre reduced the degree of crystallinity of the r-PP/PE but an improvement can be observed after the second step of heating and cooling.

Characteristics of Biodegradable Polylactide/Thermoplastic Starch/Nanosilica Composites: Effects of Plasticizer and Nanosilica Functionality

The effect of plasticizer (polydimethylsiloxanol) and neat (SiO2) or modified (having amine functional groups) silica (A‐SiO2) on morphology, thermal, mechanical, and rheological properties of PLA/TPS blends compatibilized by maleated PLA (MPLA) was investigated. Toughened PLA/MPLA/TPS (60/10/30) blend containing 3 wt.% of plasticizer and various contents (1, 3, or 5 wt.%) of silica were prepared in a corotating twin‐screw extruder. From SEM, it is clear that plasticized PLA/MPLA/TPS blend continuous porous structure is highly related to the silica content and its functionality. The results indicate that polydimethylsiloxanol enhances ductility and the initial thermal stability of the plasticized blend. DSC and DMTA analyses show that nucleation ability and reinforcing effect of A‐SiO2 on plasticized blend crystallization are much better than those of SiO2. Silica practically had no effect on the thermo‐oxidative degradation. However, the composites with A‐SiO2 had better thermal stability than those with SiO2. Moreover, silica significantly improved the elongation at break.

Utilisation of recycled thermoplastics sourced from rejected-unused disposable diapers as polymer blends

The blending of two or more thermoplastics could produce polymer blends, which are preferable compared to developing a new type of plastic. This paper presents the study on the utilisation of recycled thermoplastic polymers which are recovered from rejected-unused disposable diapers. The aim of study is to characterise the effect of manufacturing temperature on the tensile and morphological properties of recycled plastic blend. Besides that, the polymer blend sourced from virgin materials was also prepared to compare the properties. The recycled and virgin materials were blended by using an internal mixer with fixed parameters. Later, the blended materials were crushed and moulded using hot compression moulding with temperature variations of 180 °C, 190 °C and 200 °C. The tensile tests were conducted in accordance with the ASTM D638 using a universal testing machine, followed by scanning electron morphological analysis. The results showed that as temperature increases, tensile strength decreases and tensile strain increases for both recycle and virgin blends. Tensile strength and strain for the recycled blend were also lower than the virgin blend at all temperatures, due to low miscibility in the recycled blend compared to the virgin one. The low miscibility caused more macrophase separation and resulted in poor adhesion between the polymer components. Also, the increase of temperature caused the tensile modulus to be reduced for the recycled blend. Meanwhile for the virgin blend, the modulus reduced at 190 °C but increased suddenly at temperature of 200 °C.

Macrofouling communities and the degradation of plastic bags in the sea: an insitu experiment.

The increasing amount of plastic littered into the sea may provide a new substratum for benthic organisms. These marine fouling communities on plastic have not received much scientific attention. We present, to our knowledge, the first comprehensive analysis of their macroscopic community composition, their primary production and the polymer degradation comparing conventional polyethylene (PE) and a biodegradable starch-based plastic blend in coastal benthic and pelagic habitats in the Mediterranean Sea. The biomass of the fouling layer increased significantly over time and all samples became heavy enough to sink to the seafloor. The fouling communities, consisting of 21 families, were distinct between habitats, but not between polymer types. Positive primary production was measured in the pelagic, but not in the benthic habitat, suggesting that large accumulations of floating plastic could pose a source of oxygen for local ecosystems, as well as a carbon sink. Contrary to PE, the biodegradable plastic showed a significant loss of tensile strength and disintegrated over time in both habitats. These results indicate that in the marine environment, biodegradable polymers may disintegrate at higher rates than conventional polymers. This should be considered for the development of new materials, environmental risk assessment and waste management strategies.

Rheology of Green Plasticizer/Poly(vinyl chloride) Blends via Time–Temperature Superposition

Plasticizers are commonly added to poly(vinyl chloride) (PVC) and other brittle polymers to improve their flexibility and processing properties. Phthalate plasticizers such as di(2-ethylhexyl phthalate) (DEHP) are the most common PVC plasticizers and have recently been linked to a wide range of developmental and reproductive toxicities in mammals. Our group has developed several replacement compounds that have good biodegradation kinetics, low toxicity profiles, and comparable plasticizer properties to DEHP. Knowledge of the rheology of PVC–plasticizer blends at elevated temperatures is crucial for understanding and predicting the behavior of the compounds during processing. In this work, the time–temperature profiles of PVC blended with our replacement green plasticizers—succinates, maleates, and dibenzoates, of varying alkyl chain length—are compared to blends prepared with DEHP and a commercially available non-phthalate plasticizer, di(isononyl cyclohexane-1,2-dicarboxylate) (Hexamoll® DINCH®). The relationship between the plasticizer molecular structure and viscoelastic response was examined by applying time–temperature superposition. All compounds except the diethyl esters showed a comparable viscoelastic response to DEHP and Hexamoll® DINCH®, and dihexyl succinate exhibited the most effective reduction of the storage modulus G′. All of the dibenzoate blends exhibited a lower stiffness than the DEHP blends. These experiments help to show that the green plasticizers described herein are viable replacements for DEHP, providing a less toxic alternative with comparable processing and rheological performance.

Effect of compatibilizer on the final performance of linear low density polyethylene/e-waste plastic blends

This paper reports recycling of electronic waste (e-waste) by means of a melt blending process, using linear low density polyethylene with a twin screw extruder to achieve an ecological and economic outcome. It was observed that the addition of compatibilizer led to an enhancement overall of the properties of the blends as compared to uncompatibilized blends, owing to better dispersion in the presence of compatibilizer. The ultimate goal was to develop environmentally friendly polymer blends filled with e-waste plastic.

Characterization of plastic beach debris finalized to its removal: a proposal for a recycling scheme.

Characterization of beach debris is crucial to assess the strategy to answer questions such as recycling. With the aim to assess its use in a recycling scheme, in this note, we carried out a physical and chemical characterization of plastic litter from a pilot beach in Central Italy, using the FT-IR spectroscopy and thermoanalysis. Fourteen polymers, having mainly thermoplastic origin, were identified; among them, the most represented are polyethylene (41.7%) and polypropylene (36.9%). Chemical and mechanical degradation were clearly observed by an IR spectrum. The thermogravimetric analysis curve of the plastic blend shows the melting point at 120-140°C, and degradation occurs almost totally in a one-step process within 300-500°C. The high heating value of the plastic debris is 43.9MJkg-1. Polymer blends obtained by beach debris show mechanical properties similar to the virgin high-density polyethylene polymer. Following the beach plastic debris characterization, a recycling scheme was suggested.

Polyolefin-functionalized graphene oxide and its GO/HDPE nanocomposite with excellent mechanical properties

To prepare GO/Polyolefin nanocomposites with enhanced mechanical, electrical, or thermal properties is still a challenge due to the poor interfacial adhesion between GO and non-polar polyolefins. In this study, we report an effective strategy for the polyolefin-functionalized graphene oxide (fGO) using two-step methods GO was firstly modified by using glycidyl methacrylate (GMA) and styrene (St) dual monomers grafting method, thus GO-g-(GMA-co-St) with numerous epoxide groups is obtained. Then through the reaction between the epoxide group of GMA and anhydride group of maleic anhydrides (MAH) of the prepared HDPE-g-(MAH-co-St), GO-g-HDPE-g-(MAH-co-St) could be obtained. The successful preparation of the GO-g-HDPE-g-(MAH-co-St) was confirmed by AFM, TEM, FTIR, XRD, DSC, and TGA characterization. The results show the grafting ratios of the poly(GMA-co-St) and HDPE-g-(MAH-co-St) being up to 50.4wt% and 70.4wt%, respectively. The functionalized GO shows homogeneous dispersion in the nanocomposites with HDPE, and the stress at break and strain at break of the nanocomposite is increased by 28.7% and 130% respectively with only 0.2wt% fGO loading. The approach of the polyolefin-functionalized GO paves a new way to develop not only polyolefin/graphene nanocomposites but also excellent nanocomposites of polyolefin/engineering plastic blends with graphene.

Recycled plastic granules and demolition wastes as construction materials: Resilient moduli and strength characteristics

Vast quantities of plastic and demolition wastes are generated annually by municipal and commercial industries in all developed and developing countries. The sustainable usage of recycled plastic and demolition wastes as alternative construction materials has numerous environmental and economic advantages. New opportunities to recycle plastic and demolition wastes into alternative resource materials for construction industries would mitigate landfill issues and significantly reduce global carbon emissions. Infrastructure projects typically consume significant quantities of virgin quarry materials, hence the usage of plastic and demolition wastes as alternative construction materials will divert significant quantities of these wastes from landfills. In this research, three types of recycled plastic waste granules: Linear Low Density Polyethylene filled with Calcium Carbonate (LDCAL), High Density Polyethylene (HDPE) and Low Density Polyethylene (LDPE) were evaluated in blends with Crushed Brick (CB) and Reclaimed Asphalt Pavement (RAP). The blends prepared were evaluated in terms of strength, stiffness and resilient moduli. Resilient moduli prediction models were proposed using Repeated Load Triaxial (RLT) tests to characterize the stiffness properties of the plastic/demolition waste blends. Polyethylene plastic granules with up to 5% content were found to be suitable as a road construction material, when blended in supplementary amounts with demolition wastes. This research is significant, as the usage of plastics as a construction material, in combination with demolition wastes will expedite the adoption of recycled by-products by construction industries. Furthermore, the plastic blends were prepared without the requirement for any further operations, such as reshaping plastic granules into fibers, hence leading to significant energy and costs savings.

Impact of plastic blends on the product yield from co-pyrolysis of lignin-rich materials

Co-pyrolysis of lignin-rich materials with two types of plastic waste blends was evaluated. Blend 1 (B1) comprised 30% m/m styrene-butadiene rubber (SBR, from rubber granules used tires), 40% m/m polyethylene terephthalate (PET, from scrap bottles), and 30% m/m polypropylene (PP, from scrap bumpers). Blend 2 (B2) comprised 40% m/m PET (from scrap bottles), 30% m/m PP (from automotive scrap), and 30% m/m acrylonitrile-butadiene-styrene copolymer (ABS, from automotive scrap). The lignin-rich materials evaluated were wood biomass, agrarian biomass, and waste from furniture. The feedstock-to-product energy conversion efficiency (FP-ECE) was also studied. Samples were thermally treated from room temperature to 400 or 600°C at a heating rate of 10°Cmin−1 under N2 at a flow rate of 3dm3min−1. In light of the experimental results, an appropriate temperature for the fixed-bed pyrolysis of biomass-plastic mixtures with various ratios was determined and the raw materials were pyrolysed under the same conditions. The solid (char), liquid and gaseous products of pyrolysis were analysed. The pyrolysis experiments and analysis of variance showed that the combination of biomass with plastic materials had a positive effect on the liquid and gas yields.

Thermal behavior of vehicle plastic blends contained acrylonitrile-butadiene-styrene (ABS) in pyrolysis using TG-FTIR

As important plastic blends in End-of-Life vehicles (ELV), pyrolysis profiles of ABS/PVC, ABS/PA6 and ABS/PC were investigated using thermogravimetric-Fourier transform infrared spectrometer (TG-FTIR). Also, CaCO3 was added as plastic filler to discuss its effects on the pyrolysis of these plastics. The results showed that the interaction between ABS and PVC made PVC pyrolysis earlier and HCl emission slightly accelerated. The mixing of ABS and PA6 made their decomposition temperature closer, and ketones in PA6 pyrolysis products were reduced. The presence of ABS made PC pyrolysis earlier, and phenyl compounds in PC pyrolysis products could be transferred into alcohol or H2O. The interaction between ABS and other polymers in pyrolysis could be attributed to the intermolecular radical transfer, and free radicals from the polymer firstly decomposed led to a fast initiation the decomposition of the other polymer. As plastic filler, CaCO3 promoted the thermal decomposition of PA6 and PC, and had no obvious effects on ABS and PVC pyrolysis process. Also, CaCO3 made the pyrolysis products from PA6 and PC further decomposed into small-molecule compounds like CO2. The kinetics analysis showed that isoconversional method like Starink method was more suitable for these polymer blends. Starink method showed the average activation energy of ABS50/PVC50, ABS50/PA50 and ABS50/PC50 was 186.63kJ/mol, 239.61kJ/mol and 248.95kJ/mol, respectively, and the interaction among them could be reflected by the activation energy variation.

Antibacterial and Drug Elution Performance of Thermoplastic Blends

Food preservatives or drug compounds can be eluted from polymer substrates to prevent the occurrence of hospital-acquired infections and food spoilage. We investigated the antimicrobial and drug-elution properties of the albumin and zein thermoplastic blends plasticized with glycerol and mixed with varying amounts of low-density polyethylene (LDPE), food preservatives (sodium benzoate or sodium nitrite), and drugs (ampicillin or ciprofloxacin). Bacillus subtilis and Escherichia coli were utilized as Gram (+) and Gram (−) species, respectively, for antimicrobial and drug-elution analyses, since these species are common in the human body and in food environments. The amount of contamination occurring in food and medical applications could be limited with usage of plastic blends made from thermomechanical molding of proteins (albumin from hen egg white and zein from corn), drug eluting compounds, and low-density polyethylene.

Characterization of plastic blends made from mixed plastics waste of different sources.

This paper studies the recyclability of construction and household plastic waste collected from local landfills. Samples were processed from mixed plastic waste by injection moulding. In addition, blends of pure plastics, polypropylene and polyethylene were processed as a reference set. Reference samples with known plastic ratio were used as the calibration set for quantitative analysis of plastic fractions in recycled blends. The samples were tested for the tensile properties; scanning electron microscope-energy-dispersive X-ray spectroscopy was used for elemental analysis of the blend surfaces and Fourier transform infrared (FTIR) analysis was used for the quantification of plastics contents.

Characterization of wood plastic composites manufactured from recycled plastic blends

The possibility of using recycled plastic waste for the manufacturing of wood-plastic composites is investigated. The samples were processed from the “light” fraction of construction plastic waste and municipal mixed plastic waste, and tested for flexural, tensile, and un-notched impact strength, hardness properties and water absorption. Thermal analysis was performed by differential scan calorimetry and thermogravimetric analysis methods; scan electron microscopy was used for morphology study of the composites. It was found that the strength of the composites was poorer than those of the reference manufactured from virgin low density polyethylene; the hardness was comparable and stiffness higher than those of the reference. The wettability of the reference was the lowest of the studied composites.

Understanding the Compatibility of the Energetic Binder PolyNIMMO with Energetic Plasticizers: Experimental and DFT Studies

AbstractThe development of energetic binders with suitable energetic plasticizers is required to enhance the mechanical properties and to reduce the glass transition temperature of propellant and explosive formulations. The compatibility of the energetic binder poly(3‐nitratomethyl‐3‐methyloxetane) (polyNIMMO) with five different energetic plasticizers viz. bis(2,2‐dinitro propyl)acetal (BDNPA), dinitro‐diaza‐alkanes (DNDA‐57), 1,2,4‐butanetriol trinitrate (BTTN), N‐N‐butyl‐N‘(2‐nitroxy‐ethyl) nitramine (BuNENA) and diethyleneglycoldinitrate (DEGDN) was studied by differential scanning calorimetry (DSC), rheology, and DFT methods. The results obtained for the pure binder were compared with the results obtained for the binder/plasticizer blend in regard of the decomposition temperature and the format of the peak indicated the compatibility of polyNIMMO with the plasticizers. The glass transition temperatures of the blends were determined by low temperature DSC and showed desirable lowering of glass transition temperature with single peak. The rheological evaluation revealed that the viscosity of the binder is considerably lowered by means of flow behavior upon addition of 20 % (w/w) plasticizer. The addition of BuNENA and DEGDN has maximum effect on the lowering of viscosity of polyNIMMO. The predicted relative trend of interaction energies between plasticizer and binder is well correlated with the corresponding trend of viscosity of binder/plasticizer blends. These experimental studies verified by theoretical methods are valuable to design practical blends of new plasticizers and binders.

Viability Study of Use of Reprocessed High Density Polyethylene for Manufacturing Products and Multi Response Optimization of Injection Moulding Parameters Using Grey Relational Analysis

In landfill, it was found that the majority of the plastic items are not biodegradable and very gradually degrade. With reprocessed consumer plastics, many attempts have been made to reduce the impact on the environment and to avoid the consumption of virgin plastics. The plastic blend of 50% reprocessed high density polyethylene (HDPE) and 50% virgin HDPE has been used purposely for this study. Usability of reprocessed HDPE as alternative for virgin HDPE is investigated.This paper investigates the influence of the process parameters melt temperature, holding pressure, and cooling time on tensile strength and flexural strength through Taguchi methodology and grey relational analysis in Injection moulding machine. Multi response characteristics like tensile and flexural strengths are selected to evaluate the process performance and the corresponding moulding parameters of the melt temperature, holding pressure, and cooling time. Optimal combination of injection moulding parameters is determined using Taguchi and Grey relational analysis. Tensile and flexural strengths of the reprocessed HDPE are found close to that of virgin HDPE. Hence, reprocessed HDPE is found a good alternative for virgin HDPE. The confirmation results reveal that, there is significant progress in tensile strength and flexural strength of reprocessed HDPE and Grey relational grade are improved by 6%, 5% and 74% respectively. Optimal combination of the process parameters for the multi-performance characteristics of the reprocessed HDPE is the set with melting temperature at 235 °C, holding pressure at 250 N/m2and cooling time at 25 s.