The effect of silane treatment on nanosized carica papaya seed modified pullulan as biocoagulant in wastewater treatment

Currently, conventional wastewater treatment process used chemical coagulant such as Aluminium sulphate. However, the residual aluminium in treated wastewater causes toxicity and serious health issues such as Alzheimer’ disease. Thus, in this study the potential of nanosized Carica Papaya (CP) seeds treated by silane coupling agent incorporated to pullulan on wastewater treatment was investigated. The biocoagulant produce prepared at a different composition of CP range from 1% to 9% was used to treat sewage wastewater. The biocoagulant was characterized by particle size analyser, FTIR and FESEM. The treated wastewater was analyzed by jar test in term of turbidity, pH, dissolved oxygen and Total Suspended Solid with biocoagulant dosage at 0.6 g/L. The size of nanosized biocoagulant was obtained at 608.9 nm. Silane treatment provides well dispersion of nanosized Carica Papaya seed powder in the pullulan matrix phase. FTIR analysis shows the presence of O-H, C=O and Si-O-CH3 bond. The highest turbidity reduction observed at the composition of nanosized CP5/P and silane treated nanosized CP5/P up to 93.89% and 93.98% respectively. However, no significant changes observed on turbidity reduction with increasing CP seeds content for both biocoagulant. Further, at these compositions, the TSS reduced up to 20% and 60% respectively. The DO value of wastewater decreased from the initial value and the increased the pH from 6.58 to 6.69 lead to the neutral condition. Therefore, the effectiveness of both untreated and silane treated biocoagulant were further confirmed upon textile wastewater with turbidity reduction achieved up to 7.84% and 14.54 % respectively. Overall, silane treatment enhanced the effectiveness of nanosized CP modified pullulan as biocoagulant

Tensile Properties of Natural Fibre Reinforced Polymer Composite Foams: A Systematic Review

Biodegradable foam packaging was chosen as an alternative food packaging material due to non-toxic and produced from renewable sources. Researchers has turned to incorporate natural fibre to enhance the mechanical properties of polymer composite foam. In this study, the objective is to identify the studies which investigated on the tensile properties of natural fiber incorporated polymer composite foam, and analyzed the effect of natural fibre content and size on tensile properties. Further correlation between the natural fibre content and size on tensile properties of composite polymer foam was conducted. The studies on the natural fibre incorporated polymer composite was identify via PRISMA method. The effect of natural fibre content and natural fibre size on tensile properties of polymer composite foam were analyzed in terms of qualitative analysis via systematic review. This study employs systematic review method on the existing literature. This study has utilized supplementary databases such as SAGE Journals, ScienceDirect, Taylor & Francis, Emerald Insight, ERIC ProQuest, SpringerLink and IEEE Xplore to cater all the possible relevant literature for a comprehensive review. The systematic review method comprised of the steps that explain on the review process in the sequence of the (identification, screening, eligibility), data analysis and data abstraction. From the article used in this systematic review, most of the result shown the increased tensile properties on natural fibre reinforced polymer composite foams. The study by Texteira et al. (2014) shows that the softwood fibre with 33% of PLA loading has the highest elongation at break, and highest natural fibre size (2470 µm). While the study by Long et al. (2019) has the highest tensile strength with 30% of ABF fibre content. The composition of 20 wt% BF with 80 wt% PLA composite were concluded to have the optimum tensile properties

Comparative study on micronsized and nanosized carica papaya seed modified pullulan as biocoagulant in wastewater treatment

Plant-based coagulants have been used as an alternative material to replace chemical coagulant in wastewater treatment. So far, limited information was found on the incorporation of plant-based biocoagulant to natural polymers and the effect of particle size upon wastewater treatment application. Thus, this study was conducted to explore the effectiveness of micronsized and nanosized Carica Papaya (CP) seed modified pullulan as biocoagulant. Biocoagulant were prepared at different composition of CP to pullulan, with the CP content range from 1% to 9%. The biocoagulant were characterized via Particle Size Analyzer (PSA), Fourier Transform Infrared Spectroscopy (FTIR) and morphological analysis via Field Emission Scanning Electron Microscopy (FESEM). It was used to treat municipal wastewater. The treated wastewater quality was analyzed by jar test method with dosage of biocoagulant used was 0.6g/L. Result showed that the 10% (D10), 50% (D50) and 90% (D90) distribution of micronsized CP had particle size of 0.3675 μm, 0.8433 μm and 1.9537 μm respectively. The nanosized CP was 0.4473nm (D10), 2.3758nm (D50) and 2.9938nm (D90). Characterization of biocoagulant via FTIR revealed the appearance of O-H, C=O, C-H and C-O-C bond which contribute to particle interaction for turbidity reduction of wastewater. Jar test analysis found that at 3% micronsized CP and 7% nanosized CP were able to reduce turbidity up to 59.65% and 65.27% respectively. Both size of biocoagulant slightly changed the pH of treated wastewater to neutral, increased in dissolved oxygen (DO) and reduced in total suspended solid (TSS). Overall, nanosized CP was found more effective as compared to micronsized CP

Mechanical, Rheological, and Bioactivity Properties of Ultra High-Molecular-Weight Polyethylene Bioactive Composites Containing Polyethylene Glycol and Hydroxyapatite

Ultrahigh-molecular-weight polyethylene/high-density polyethylene (UHMWPE/HDPE) blends prepared using polyethylene glycol PEG as the processing aid and hydroxyapatite (HA) as the reinforcing filler were found to be highly processable using conventional melt blending technique. It was demonstrated that PEG reduced the melt viscosity of UHMWPE/HDPE blend significantly, thus improving the extrudability. The mechanical and bioactive properties were improved with incorporation of HA. Inclusion of HA from 10 to 50 phr resulted in a progressive increase in flexural strength and modulus of the composites. The strength increment is due to the improvement on surface contact between the irregular shape of HA and polymer matrix by formation of mechanical interlock. The HA particles were homogenously distributed even at higher percentage showed improvement in wetting ability between the polymer matrix and HA. The inclusion of HA enhanced the bioactivity properties of the composite by the formation of calcium phosphate (Ca-P) precipitates on the composite surface as proven from SEM and XRD analysis

Thermal and mechanical properties of ultrahigh molecular weight polyethylene/high-density polyethylene/polyethylene glycol blends.

Blends of ultrahigh molecular weight polyethylene (UHMWPE) with high-density polyethylene (HDPE) provide adequate mechanical properties for biomedical application. In this study, the mechanical and thermal properties of UHMWPE/HDPE blends with the addition of polyethylene glycol (PEG) prepared via single-screw extruder nanomixer were investigated. The UHMWPE/HDPE blends exhibit a gradual increase in strength, modulus, and impact strength over pure polymers, suggesting synergism in the polymer blends. The elastic and flexural modulus was increased at the expense of tensile, flexural, and impact strength for the blends containing PEG. The degradation temperature of UHMWPE was improved with the incorporation of HDPE due to good thermal stability of HDPE. HDPE improved the dispersibility of PEG in matrix, consequently reduced the surface area available for the kinetic effects, and reduced the degradation temperature. The morphology analysis confirmed the miscibility between UHMWPE and HDPE and the changes in polymer structure with the presence of PEG modify the thermal behavior of the blends. The mechanical properties of the blends that are underlying values for the design of implant material show the potential used as biomedical devices

Mechanical properties of rice husk filled impact modified unplasticised poly(vinyl chloride) composite

Rice husk (RH) is one of the natural fillers that offer a number of advantages over inorganic fillers since they are biodegradable, low cost, recyclable and renewable. This study investigates the performance of RH as filler for unplasticised poly(vinyl chloride) (PVC-U) composites. In the sample preparation, composites with different RH loadings varied from 10 to 40 phr were prepared using two-roll mill at temperature 165 oC before being hot pressed at temperature 185 oC. Tensile, flexural and izod impact test were conducted in order to investigate the mechanical properties of the composites. Incorporation of RH fillers from 10 to 40 phr has resulted in the increased of flexural modulus indicating an improvement in stiffness. The effects of acrylic impact modifier and LICA 12 coupling agent on the mechanical properties of PVC-U composites were investigated. The acrylic impact modifiers were found to be effective in enhancing the impact strength at all levels of RH content. Effectiveness of the impact modifier in enhancing the impact strength decreased with increasing RH content. LICA 12 was found to be the most effective in increasing impact strength at 20 phr RH loading. The processability of RH filled PVC-U composites was studied by using Brabender Plasticorder. It was found that incorporation of RH has resulted in decreasing the fusion time of the PVC compounds while the heat distortion temperature (HDT) increased at all RH loadings. The degradation temperature (T10%) decreased with increasing RH content. The percentage of water absorption increased slightly with increasing RH content and treated samples exhibited lower percentage of water absorption compared to the untreated samples. The optimum composition which gives balance of properties based on stiffness and toughness of PVC-U composites is PVC-U at 8 phr of acrylic impact modifier and 20 phr of RH treated with LICA 1

Mechanical properties of unplasticised PVC (PVC-U) containing rice husk and an impact modifier

The objective of this study was to investigate the effects of rice husk and acrylic impact modifiers on the mechanical properties of unplasticised poly(vinyl chloride) (PVC-U) composites. The composites were prepared using a two-roll mill at temperature 165 °C before being hot pressed at 185 °C. The incorporation of rice husk (RH) fillers from 10 to 40 per hundred resin (phr) has increased the flexural and tensile modulus of the unmodified and modified (8 phr impact modifier) PVC-U composite. The flexural strength for both unmodified and modified PVC-U composite was observed to increase until RH loading of 20 phr. However, the tensile and impact strength of PVC-U composite decreased with RH loading. The scanning electron microscopy (SEM) showed that the rice husk fillers agglomerated and unevenly distributed throughout the matrix. The result showed that the impact strength of the filled PVC-U composites (20 phr filler) increased but the tensile and flexural properties decreased with increasing impact modifier content. The formulation containing 8 phr of acrylic impact modifier and 20 phr of RH loading showed the best balance of stiffness and toughness properties

Influence of processing aids and hydroxyapatite as fillers on flow behaviour and mechanical properties of ultra high molecular weight polyethylene/high density polyethylene composites

In this study, blends of ultra high molecular weight polyethylene/high density polyethylene/polyethylene glycol (UHMWPE/HDPE/PEG) and the composites containing Hydroxyapatite (HA) as reinforcement filler were prepared via single screw extruder nanomixer followed by compression moulding. PEG (2phr) was used as processing aid and HA loadings were varied from 10 to 50 phr. HDPE and PEG were introduced to improve the extrudability of UHMWPE. Rheological behavior was studied via capillary rheometer while flexural and izod impact tests were conducted in order to investigate the mechanical properties of the blends and composites. Melt viscosity of the blends was found to decrease with increasing shear rate indicating a pseudoplastic behaviour. Incorporation of PEG shows a synergism effect on the reduction of blends viscosity. Blend of 40% UHMWPE/ 60% HDPE/ 2 phr PEG was chosen as the optimum blend composition with a balance properties in terms of the mechanical properties and processability. The incorporation of HA fillers from 10 to 50 phr into the blend resulted in the increase of flexural modulus and flexural strength with a slight decline of impact strength values. It can be concluded that the composites having adequate strength and modulus within the range of cancellous bone properties were succesfully developed to be used as biomedical implant devices

Mechanical Properties of Rice Husk Filled Impact Modified PVC-U Composite

The growing interest in environmentally friendly materials has produced reevaluation of organic materials as fillers in plastics. Composite materials made from plant fibre are receiving a great deal of attention today since they are biodegradability, very low cost, recyclability, and renewable nature. Rice husk (RH) is one of the natural fillers that offer a number of advantages over inorganic fillers. This study investigates the performance of RH as filler for unplasticised polyvinyl chloride (PVC-U) composites. Acrylic impact modifier at 4,8,10 and 12 phr were used to enhance the impact properties of PVC. The composites with RH loadings varied from 10 to 40phr were prepared using two roll mill at temperature 165oC for 10 minutes of milling time. The composites milled sheets were then placed into a mould and hot pressed at temperature 185oC and pressure of 120kg/m2 for 5 minutes. The cooling time used was 5 minutes before the specimens being removed from the mould. Testing such as tensile, flexural and izod impact test were conducted in order to investigate the mechanical properties of the composites. It was found that incorporation of RH improved the Young modulus and flexural modulus of the composites. However, tensile strength, elongation at break, flexural strength and impact strength decreased with increasing RH content of impact modified PVC-U composites. Impact modifier has resulted in enhancing the impact strength at all levels of RH content. The improvement was about 8 to 30% from 40 to 10phr of RH. Effectiveness of the impact modifier in enhancing the impact strength decreased with increasing RH content. From the result, it may conclude that the impact properties of the composites are optimized at 8phr of acrylic impact modifier content, and the optimum compositions which give a balance properties of PVC-U composites is at 20phr of RH and 8phr of acrylic impact modifier

Barrier properties of pullulan/starch based films modified with lauric acid

Enormous attention has been given in developing active food packaging materials in order to reduce the environmental effects caused by conventional packages. Recent scenario has turned into developing the food packaging materials based on biodegradable polymers such as starch-based materials. Starch, an agricultural raw material was chosen to be developed as it is widely available in nature, renewable and cheap. In this study, the potential of pullulan modified starch based films was investigated with the incorporation of lauric acid. Three types of film were prepared which are starch as control, starch/pullulan as well as starch/pullulan/lauric acid via casting technique. The barrier properties of these blends were assessed via Water Vapor Transmission Rate (WVTR. Further characterization of the blends was conducted via Fourier Transform Infrared Spectroscopy (FTIR) and the surface morphology of the film by Scanning Electron Microscopy (SEM). The results showed that the control films, starch exhibits the highest WVTR. The presence of lauric acid at highest composition of pullulan reduced the WVTR due to the hydrophobicity of the lauric acid. The C-H bond between starch, pullulan and lauric acid was detected via FTIR. The occurrence of peaks attributed to hydrogen bonding and OH group of starch. The composition which exhibited good water vapor resistant is starch modified pullulan at 7:3 ratio incorporated with lauric acid