Fast co-pyrolysis offers a sustainable solution for upcycling polymer waste, including scrap tyre and plastics. Previous studies primarily focused on slow heating rates, neglecting synergistic mechanisms and sulphur transformation in co-pyrolysis with tyre. This research explored fast co-pyrolysis of scrap tyre with polypropylene (PP), low-density polyethylene (LDPE), and polystyrene (PS) to understand synergistic effects and sulphur transformation mechanisms. A pronounced synergy was observed between scrap tyre and plastics, with the nature of the synergy being plastic-type dependent. Remarkably, blending 75 wt% PS or LDPE with tyre effectively eliminated sulphur-bearing compounds in the liquid product. This reduction in sulphur content can substantially mitigate the release of hazardous materials into the environment, emphasizing the environmental significance of co-pyrolysis. The synergy between PP or LDPE and tyre amplified the production of lighter hydrocarbons, while PS's interaction led to the creation of monocyclic aromatics. These findings offer insights into the intricate chemistry of scrap tyre and plastic interactions and highlight the potential of co-pyrolysis in waste management. By converting potential pollutants into valuable products, this method can significantly reduce the release of hazardous materials into the environment.
Residual palm oil that goes into the river untreated can become detrimental to the environment. Residual oil discharge during milling process into palm oil mill effluent (POME) is unavoidable. About 1 wt% of residual oil in POME causes major problems to the mills, in terms of environment, wastewater treatment and economy losses. This paper reports the recovery of residual oil from POME by adsorption on polypropylene micro/nanofiber (PP-MNF) and desorption of oil by hands pressing, and oil extraction from the PP-MNF using solvent and supercritical-CO2 extraction techniques. The characterization of the PP-MNF and the quality of oil extracted were analyzed using analytical instruments. The reusability of the PP-MNF was also investigated. The experimental results showed the adsorption capacity of the PP-MNF was 28.65 g of oil/g of PP-MNF on average using refined palm oil, whilst recovery of oil from POME was 10.93 g of oil/g of PP-MNF. The extraction yield of oil from PP-MNF using hand pressing was 89.62%. The extraction of residual oil from the pressed PP-MNF showed comparable yield between solvent and supercritical CO2 techniques. The quality of recovered oil was similar with the quality of the crude oil, and no trace of polypropylene contamination was detected in the oil recovered. The PP-MNF showed no significant physical change after the extraction process. In conclusion, the PP-MNF has great potential to be used commercially in residual oil recovery from POME.
Consumers today prefer to purchase ready-to-eat, fresh-cut fruit that is readily available at the markets and retailers. They generally select the fresh-cut fruit base on the quality, freshness, nutrition and safety. The effects of packaging condition on fresh-cut Cantaloupe were studied during 18 days of storage at 2°C and 87% RH. Fresh-cut Cantaloupe pieces were packed in a Polypropylene (PP) container. As a control, the container was cover with lid without film, while Sample 1 (S1) was sealed only by a 40 μm PP film and Sample 2 (S2) was sealed with a 40 μm PP film and then adding the lid cover. Changes in colour, firmness Total Soluble Solids (TSS), pH, Titratable Acidity (TA) and Total Plate Count (TPC) were evaluated over time. During storage, it was found that the firmness significantly decreased from day 0 until day in all packaging conditions. Color parameters Luminosity (L*) and Chromaticity (C) were significantly change at the significance level of 95% (p
In toxicological analysis, the analytical validation method is important to assess the exact risk of contaminants of emerging concern in the environment. Syringe filters are mainly used to remove impurities from sample solutions. However, the loss of analyte to the syringe filter could be considerable, causing an underestimate of the analyte concentrations. The current study develops and validates simultaneous liquid chromatography-mass spectrometry analysis using a direct filtration method to detect four groups of contaminants of emerging concern. The adsorption of the analyte onto three different matrices and six types of syringe filters is reported. The lowest adsorption of analytes was observed in methanol (16.72%), followed by deionized water (48.19%) and filtered surface lake water (48.94%). Irrespective of the type of the matrices, the lowest average adsorption by the syringe filter was observed in the 0.45 μm polypropylene membrane (15.15%), followed by the 0.20 μm polypropylene membrane (16.10%), the 0.20 μm regenerated cellulose (16.15%), the 0.20 μm polytetrafluoroethylene membrane (47.38%), the 0.45 μm nylon membrane (64.87%) and the 0.20 μm nylon membrane (71.30%). In conclusion, the recommended syringe filter membranes for contaminants of emerging concern analysis are polypropylene membranes and regenerated cellulose, regardless of the matrix used.
STUDY OBJECTIVE: To assess the morphologic features of anterior armed transobturator collagen-coated polypropylene mesh and its clinical outcomes in pelvic reconstructive surgery to treat pelvic organ prolapse.
DESIGN: Evidence obtained from several timed series with intervention (Canadian Task Force classification II-3).
SETTING: Chang Gung Memorial Hospital, Taoyuan, Taiwan, China.
PATIENTS: Between April 2010 and October 2012, 70 patients underwent surgery to treat symptomatic pelvic organ prolapse, stage III/IV according to the POP-Q (Pelvic Organ Quantification System).
INTERVENTION: Anterior armed transobturator collagen-coated mesh.
MEASUREMENT AND MAIN RESULTS: Morphologic findings and clinical outcome were measured. Morphologic features were assessed via 2-dimensional introital ultrasonography and Doppler studies. Clinical outcome was measured via subjective and objective outcome. Objective outcome was assessed via the 9-point site-specific staging method of the International Continence Society Pelvic Organ Prolapse Quantification before the operation and at 1-year postoperative follow-up. Subjective outcome was based on 4 validated questionnaires: the 6-item UDI-6 (Urogenital Distress Inventory), the 7-item IIQ-7 (Incontinence Impact Questionnaire), the 6-item POPDI-6 (Pelvic Organ Prolapse Distress Inventory 6), and the 12-item PISQ-12 (Pelvic Organ Prolapse/Urinary Incontinence Sexual Questionnaire), at baseline and at 12 months after the operation. Data were obtained for 65 patients who underwent the combined surgery and were able to comply with follow-up for >1 year. Ultrasound studies reveal that mesh length tends to shorten and decrease in thickness over the 1-year follow-up. Vagina thickness also was reduced. Neovascularization through the mesh was observed in <8.5% of patients in the first month and at 1 year, and was evident in approximately 83%. The mesh exposure rate was 6.4%. The recorded objective cure was 90.8% (59 of 65 patients), and subjective cure was 89.2% (58 of 65 patients) at mean (SD) follow-up of 19.40 (10.98) months. At 2 years, UDI-6, IIQ-7, and POPDI-6 scores were all significantly decreased (p < .001), whereas the PISQ-12 score was significantly increased (p = .01).
CONCLUSIONS: Ultrasound features suggest that the degeneration of collagen barrier may be longer than expected and that integration of collagen-coated mesh could occur up to 1 year. A substantially good clinical outcome was noted.
KEYWORDS: Anterior vaginal mesh; Collagen-coated mesh; Morphology; Outcome; Pelvic organ prolapse
The effect of electron beam radiation on ethylene-propylene diene terpolymer/polypropylene blends is studied as an attempt to develop radiation sterilizable polypropylene/ethylene-propylene diene terpolymer blends suitable for medical devices. The polypropylene/ethylene-propylene diene terpolymer blends with mixing ratios of 80/20, 50/50, 20/80 were prepared in an internal mixer at 165°C and a rotor speed of 50 rpm/min followed by compression molding. The blends and the individual components were radiated using 3.0 MeV electron beam accelerator at doses ranging from 0 to 100 kGy in air and room temperature. All the samples were tested for tensile strength, elongation at break, hardness, impact strength, and morphological properties. After exposing to 25 and 100 kGy radiation doses, 50% PP blend was selected for in vivo studies. Results revealed that radiation-induced crosslinking is dominating in EPDM dominant blends, while radiation-induced degradation is prevailing in PP dominant blends. The 20% PP blend was found to be most compatible for 20-60 kGy radiation sterilization. The retention in impact strength with enhanced tensile strength of 20% PP blend at 20-60 kGy believed to be associated with increased compatibility between PP and EPDM along with the radiation-induced crosslinking. The scanning electron micrographs of the fracture surfaces of the PP/EPDM blends showed evidences consistent with the above contentation. The in vivo studies provide an instinct that the radiated blends are safe to be used for healthcare devices.
Our aim is to study the inflammatory response towards the collagen-coated and non-coated polypropylene meshes in rats and the urodynamic investigation post-operatively. Forty-two female Sprague Dawley were divided into 7 groups of 6 rats; Control, Day 7 and 30 for Sham, Avaulta Plus (MPC), Perigee (MP). UDS were taken at days 7 and 30. Mesh with the vagina and bladder wall was removed and sent for immunohistochemical examination. Results showed intense inflammatory reaction on day 7 in the study groups which decreased on day 30. IL-1, TNF-α, MMP-2 and CD31 were observed to decrease from day 7 to day 30. NGF was almost normal on day 30 in all groups. UDS showed no difference in voiding pressure. Both Study and Sham groups had shorter voiding interval (VI) on day 7 but significantly lower in MPC. VI had significantly increased on day 30 in all groups. Voided volume was significantly lower in the mesh groups even when an increase was seen on day 30. In conclusion, the higher levels of IL-1, TNF-α and MMP-2 in collagen-coated polypropylene mesh imply greater inflammation than the non-coated polypropylene mesh. Mesh implantation can lead to shorter voiding interval and smaller bladder capacity.
We report two cases of large chest wall primary chondrosarcoma, one of the sternum and the other of the lateral chest wall. Both were treated by radical resection and reconstruction using marlex mesh and methyl methacrylate "sandwich" prosthesis and pedicled latissiumus dorsi flap.
This paper focuses on the synthesis and mechanism of carbon nanospheres (CNS) coated with few- and multi-layered graphene (FLG, MLG). The graphitic carbon encapsulates the core/shell structure of the Ni/NiO nanoparticles via the chemical vapor deposition (CVD) method. The application of the resulting CNS and hybrids of CNS-FLG and CNS-MLG as reinforcement nanofillers in a polypropylene (PP) matrix were studied from the aspects of mechanical and thermal characteristics. In this research, to synthesize carbon nanostructures, nickel nitrate hexahydrate (Ni(NO₃)₂·6H₂O) and acetylene (C₂H₂) were used as the catalyst source and carbon source, respectively. Besides, the morphology, structure and graphitization of the resulting carbon nanostructures were investigated. On the other hand, the mechanisms of CNS growth and the synthesis of graphene sheets on the CNS surface were studied. Finally, the mechanical and thermal properties of the CNS/PP, CNS-FLG/PP, and CNS-MLG/PP composites were analyzed by applying tensile test and thermogravimetric analysis (TGA), respectively.
Microbial extracellular hydrolytic enzymes that degrade organic matter in aquatic ecosystems play key roles in the biogeochemical carbon cycle. To provide linkages between hydrolytic enzyme activities and genomic or metabolomic studies in aquatic environments, reliable measurements are required for many samples at one time. Extracellular proteases are one of the most important classes of enzymes in aquatic microbial ecosystems, and protease activities in seawater are commonly measured using fluorogenic model substrates. Here, we examined several concerns for measurements of extracellular protease activities (aminopeptidases, and trypsin-type, and chymotrypsin-type activities) in seawater. Using a fluorometric microplate reader with low protein binding, 96-well microplates produced reliable enzymatic activity readings, while use of regular polystyrene microplates produced readings that showed significant underestimation, especially for trypsin-type proteases. From the results of kinetic experiments, this underestimation was thought to be attributable to the adsorption of both enzymes and substrates onto the microplate. We also examined solvent type and concentration in the working solution of oligopeptide-analog fluorogenic substrates using dimethyl sulfoxide (DMSO) and 2-methoxyethanol (MTXE). The results showed that both 2% (final concentration of solvent in the mixture of seawater sample and substrate working solution) DMSO and 2% MTXE provide similarly reliable data for most of the tested substrates, except for some substrates which did not dissolve completely in these assay conditions. Sample containers are also important to maintain the level of enzyme activity in natural seawater samples. In a small polypropylene containers (e.g., standard 50-mL centrifugal tube), protease activities in seawater sample rapidly decreased, and it caused underestimation of natural activities, especially for trypsin-type and chymotrypsin-type proteases. In conclusion, the materials and method for measurements should be carefully selected in order to accurately determine the activities of microbial extracellular hydrolytic enzymes in aquatic ecosystems; especially, low protein binding materials should be chosen to use at overall processes of the measurement.
Pyrolysis oil from oil palm biomass can be a sustainable alternative to fossil fuels and the precursor for synthesizing petrochemical products due to its carbon-neutral properties and low sulfur and nitrogen content. This work investigated the effect of applying mesoporous acidic catalysts, Ni-Mo/TiO2 and Ni/Al2O3, in a catalytic co-pyrolysis of oil palm trunk (OPT) and polypropylene (PP) from 500 to 700 °C. The obtained oil yields varied between 12.67 and 19.50 wt.% and 12.33-17.17 wt.% for Ni-Mo/TiO2 and Ni/Al2O3, respectively. The hydrocarbon content in oil significantly increased up to 54.07-58.18% and 37.28-68.77% after adding Ni-Mo/TiO2 and Ni/Al2O3, respectively. The phenolic compounds content was substantially reduced to 8.46-20.16% for Ni-Mo/TiO2 and 2.93-14.56% for Ni/Al2O3. Minor reduction in oxygenated compounds was noticed from catalytic co-pyrolysis, though the parametric effects of temperature and catalyst type remain unclear. The enhanced deoxygenation and cracking of phenolic and oxygenated compounds and the PP decomposition resulted in increased hydrocarbon production in oil during catalytic co-pyrolysis. Catalyst addition also promoted the isomerization and oligomerization reactions, enhancing the formation of cyclic relative to aliphatic hydrocarbon.
The incorporation of kenaf fiber fillers into a polymer matrix has been pronounced in the past few decades. In this study, the effect of multiwalled carbon nanotubes (MWCNTs) with a short kenaf fiber (20 mesh) with polypropylene (PP) added was investigated. The melt blending process was performed using an internal mixer to produce polymer composites with different filler contents, while the suitability of this melt composite for the injection molding process was evaluated. Thermogravimetric analysis (TGA) was carried out to investigate the thermal stability of the raw materials. Rheological analyses were conducted by varying the temperature, load factor, and filler content. The results demonstrate a non-Newtonian pseudoplastic behavior in all samples with changed kenaf fillers (10 to 40 wt %) and MWCNT contents (1 to 4 wt %), which confirm the suitability of the feedstock for the injection molding process. The addition of MWCNTs had an immense effect on the viscosity and an enormous reduction in the feedstock flow behavior. The main contribution of this work is the comprehensive observation of the rheological characteristics of newly produced short PP/kenaf composites that were altered after MWCNT additions. This study also presented an adverse effect on the composites containing MWCNTs, indicating a hydrophilic property with improved water absorption stability and the low flammability effect of PP/kenaf/MWCNT composites. This PP/kenaf/MWCNT green composite produced through the injection molding technique has great potential to be used as car components in the automotive industry.
Traumatic diaphragmatic rupture and traumatic abdominal wall hernia are two well-described but rare clinical entities associated with blunt thoracoabdominal injuries. To the best of our knowledge, the combination of these two clinical entities as a result of a motor vehicle accident has not been previously reported.
Since ancient Egypt, orthosis was generally made from wood and then later replaced with metal and leather which are either heavy, bulky, or thick decreasing comfort among the wearers. After the age of revolution, the manufacturing of products using plastics and carbon composites started to spread due to its low cost and form-fitting feature whereas carbon composite were due to its high strength/stiffness to weight ratio. Both plastic and carbon composite has been widely applied into medical devices such as the orthosis and prosthesis. However, carbon composite is also quite expensive, making it the less likely material to be used as an Ankle-Foot Orthosis (AFO) material whereas plastics has low strength. Kenaf composite has a high potential in replacing all the current materials due to its flexibility in controlling the strength to weight ratio properties, cost-effectiveness, abundance of raw materials, and biocompatibility. The aim of this review paper is to discuss on the possibility of using kenaf composite as an alternative material to fabricate orthotics and prosthetics. The discussion will be on the development of orthosis since ancient Egypt until current era, the existing AFO materials, the problems caused by these materials, and the possibility of using a Kenaf fiber composite as a replacement of the current materials. The results show that Kenaf composite has the potential to be used for fabricating an AFO due to its tensile strength which is almost similar to polypropylene's (PP) tensile strength, and the cheap raw material compared to other type of materials.
Manual workers in plastics industry are often exposed to work related discomfort and pain while performing their daily
task. These exposure leads to common occupational diseases such as Work-related Musculoskeletal Disorder (WMSD) or
low back pain (LBP) which in turn will affect their working performance. The main objective for this study is to
analyse the working posture of a manual worker that works in a polypropylene fibrillated yarn industry using RULA
assessment in CATIA P3 V5R14 software. The subject were selected from the packaging area as the manual handling
work are only present in that area. Based on the RULA analysis done by constructing the worker posture in the
software, several awkward postures were identified to be high in risk factors. The postures that is high in risk is
postures 3 which is due to lifting heavy loads and twisting or turning of the trunk. The postures obtained the final
RULA analysis score of 7 and this indicates that changes must be done immediately. It is recommended that the
company should increase the ergonomic awareness among the manual workers especially while performing their work
and to redesign the working posture for the manual workers.
This paper investigates the selectivity of GMA-based-non-woven fabrics adsorbent towards copper ion (Cu) functionalized with several aliphatic amines. The aliphatic amines used in this study were ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetetramine (TETA), and tetraethylenepentamine (TEPA). The non-woven polyethylene/polypropylene fabrics (NWF) were grafted with glycidyl methacrylate (GMA) via pre-radiation grafting technique, followed by chemical functionalization with the aliphatic amine. To prepare the ion recognition polymer (IRP), the functionalized amine GMA-grafted-NWF sample was subjected to radiation crosslinking process along with the crosslinking agent, divinylbenzene (DVB), in the presence of Cu ion as a template in the matrix of the adsorbent. Functionalization with different aliphatic amine was carried out at different amine concentrations, grafting yield, reaction temperature, and reaction time to study the effect of different aliphatic amine onto amine density yield. At a concentration of 50% of amine and 50% of isopropanol, EDA, DETA, TETA, and TEPA had attained amine density around 5.12, 4.06, 3.04, and 2.56 mmol/g-ad, respectively. The amine density yield decreases further as the aliphatic amine chain grows longer. The experimental condition for amine functionalization process was fixed at 70% amine, 30% isopropanol, 60 °C for grafting temperature, and 2 h of grafting time for attaining 100% of grafting yield (Dg). The prepared adsorbents were characterized comprehensively in terms of structural and morphology with multiple analytical tools. An adsorptive removal and selectivity of Cu ion by the prepared adsorbent was investigated in a binary metal ion system. The IRP samples with a functional precursor of EDA, the smallest aliphatic amine had given the higher adsorption capacity and selectivity towards Cu ion. The selectivity of IRP samples reduces as the aliphatic amine chain grows longer, EDA to TEPA. However, IRP samples still exhibited remarkably higher selectivity in comparison to the amine immobilized GMA-g-NWF at similar adsorption experimental conditions. This observation indicates that IRP samples possess higher selectivity after incorporation of the ion recognition imprint technique via the radiation crosslinking process.
A nanocomposite containing polypropylene (PP) and nano α-Al2O3 particles was prepared using a Haake internal mixer. Mechanical tests, such as tensile and flexural tests, showed that mechanical properties of the composite were enhanced by addition of nano α-Al2O3 particles and dispersant agent to the polymer. Tensile strength was approximately ∼ 16% higher than pure PP by increasing the nano α-Al2O3 loading from 1 to 4 wt% into the PP matrix. The results of flexural analysis indicated that the maximum values of flexural strength and flexural modulus for nanocomposite without dispersant were 50.5 and 1954 MPa and for nanocomposite with dispersant were 55.88 MPa and 2818 MPa, respectively. However, higher concentration of nano α-Al2O3 loading resulted in reduction of those mechanical properties that could be due to agglomeration of nano α-Al2O3 particles. Transmission and scanning electron microscopic observations of the nanocomposites also showed that fracture surface became rougher by increasing the content of filler loading from 1 to 4% wt.
The electrical resistivity and flexural strength of plastic composites reinforced with pineapple leaf particles (PCPLP) is presented. PCPLP were produced using different plastic materials; Polyethylene (PE) and Polypropylene (PP), and different plastic pineapple leaf particle ratios; 50:50 and 70:30. The PCPLP were tested and evaluated with respect to electrical resistivity and flexural strength according to ASTM D257 and D790, respectively. The results indicate that PCPLP made from PP exhibits better electrical resistance than PE, which may be attributed to the better frequency insulation behaviour ofPP. PCPLP using the higher ratio of 70:30 also exhibited better electrical resistance than the lower 50:50 ratio. Cellulose materials inherently influence the electrical resistance of plastic composites, due to their natural propensity to absorb moisture. The PCPLP produced using a ratio of 50:50 for both PP and PE composites exhibited better MOE results than the 70:30 composites, however the converse is true with respect to the MOR. MOE of PCPLP was increased with increasing pineapple leaf particles content due to the greater matrix stiffness of this natural particle with respect to plastic matrix. However, high percentage offiller particles in the matrix (70:30 ratio) has reduced the toughness in the composite structure due to the lost ofphysical contact between high accumulated particles.
The objective of this study was to develop an optimized assay for Salmonella Typhi biofilm that mimics the environment of the gallbladder as an experimental model for chronic typhoid fever. Multi-factorial assays are difficult to optimize using traditional one-factor-at-a-time optimization methods. Response surface methodology (RSM) was used to optimize six key variables involved in S. Typhi biofilm formation on cholesterol-coated polypropylene 96-well microtiter plates. The results showed that bile (1.22%), glucose (2%), cholesterol (0.05%) and potassium chloride (0.25%) were critical factors affecting the amount of biofilm produced, but agitation (275 rpm) and sodium chloride (0.5%) had antagonistic effects on each other. Under these optimum conditions the maximum OD reading for biofilm formation was 3.4 (λ600 nm), and the coefficients of variation for intra-plate and inter-plate assays were 3% (n = 20) and 5% (n = 8), respectively. These results showed that RSM is an effective approach for biofilm assay optimization.
The present study investigates the effects of close-range blast loading of fibre metal laminates (FMLs) fabricated from woven glass polypropylene and aluminium alloy 2024-T3. The polypropylene layers and anodized aluminium are stacked in 3/2 layering configuration to investigate the impact energy absorbed through deformation and damage. In order to study the blast responses of FMLs, a 4-cable instrumented pendulum blast set-up is used. Effects of blast impulse and stand-off distance were examined. Investigation of the cross-section of FMLs are presented and damages such as fibre fracture, debonding, and global deformation are examined. Increasing stand-off distance from 4 to 14 mm resulted in a change of damage mode from highly localized perforation to global deformation.