Mechanical, thermal, and morphological properties of poly(lactic acid) (PLA)/ recycled tyre rubber waste compatibilised with chain extender

The accumulation of waste tires in our society is a pressing issue due to their short lifespan and increasing demand. This research delves into effective methods for recycling waste tires, with a particular focus on utilising biopolymers. Polylactic acid (PLA), a completely biodegradable polymer, has gained popularity for its biocompatibility, biodegradability, mechanical strength, and ease of processing. To overcome its toughness and thermal stability limitations, PLA has been blended with commercial polymers, such as rubber. Furthermore, the addition of 10% recycled tyre waste to 90% PLA has been shown to increase its durability and strength. Joncryl® ADR is used as a chain extender and reactive compatibiliser to enhance the chemical interactions in the binary blend. The samples were prepared using a twin-screw extruder with the temperature between 150 and 190 ºC and 60 rpm of screw speed. These blends are then analyzed using a range of characterization techniques, including Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), scanning electron microscopy (SEM), tensile testing, and notched Izod impact testing. The blends were then characterized by chemical changes, thermal transitions, and thermal degradation. It was found that the 90/10/0.6 (PLA/RW/ADR) nanocomposite exhibited maximum thermal degradation

Statistical study on the interaction factors of polypropylene-graft-maleic anhydride (PP-g-MA) with graphene nanoplatelet (GNP) at various Poly(Lactic Acid)/Polypropylene (PLA/PP) blends ratio

This paper reports the effects of polypropylene-graft-maleic anhydride (PP-gMA) and graphene nanoplatelet (GNP on tensile stress of various PLA/PP weight ratio. The PLA/PP blends prepared with the ratio 70/30, 80/20, and 90/10 with the addition of PP-g-MA (1 to 5 phr) and GNP (1 to 3 phr) by using an injection molding machine. The tensile stress (MPa) was analyzed based on 11 runs of full factorial design. The results showed that the tensile stress of PLA/PP blends gradually increased after the addition of PP-g-MA and GNP. There is a relationship between PP-g-MA and GNP which causes a positive impact on the mechanical properties of PLA/PP blends. The optimum tensile stress of 50.06 MPa achieved at the ratio of 90/10 blends with 5 phr of PP-g-MA and 3 phr of GN

Statistical study on the interaction factors of polypropylene-graft-maleic anhydride (PP-G-MA) with graphene nanoplatelet (GNP) at various poly(lactic acid)/polypropylene (PLA/PP) blends ratio

This paper reports the effects of polypropylene-graft-maleic anhydride (PP-g-MA) and graphene nanoplatelet (GNP on tensile stress of various PLA/PP weight ratio. The PLA/PP blends prepared with the ratio 70/30, 80/20, and 90/10 with the addition of PP-g-MA (1 to 5 phr) and GNP (1 to 3 phr) by using an injection molding machine. The tensile stress (MPa) was analyzed based on 11 runs of full factorial design. The results showed that the tensile stress of PLA/PP blends gradually increased after the addition of PP-g-MA and GNP. There is a relationship between PP-g-MA and GNP which causes a positive impact on the mechanical properties of PLA/PP blends. The optimum tensile stress of 50.06 MPa achieved at the ratio of 90/10 blends with 5 phr of PP-g-MA and 3 phr of GNP

Polyvinylidene fluoride (PVDF)/Poly (Ether Sulfones) (PES) blend membrane for CO2/ CO4 for gas separation

In this study, a combination of Polyvinylidene fluoride (PVDF) and Poly (ether sulfones) (PES) blend membrane and DMF as solvent component was developed to evaluate the CO2 and CO4 separation performance. The gas permeation test was thereafter conducted on the membrane produced. The separation through a membrane works on the theory of permeation based on permeability and selectivity. These two important values were estimated using a set of analytical functions. The membranes produced was then characterized using scanning electron microscopy (SEM) and the Fourier Transform Infrared Spectroscopy (FTIR). The result obtained revealed a higher permeability for the CO2 and CH4 gases when the blending ratio of PVDF: PES: DMF/5:15:80 were applied. Moreover, the selectivity results showed that the use of the blending ratio of PVDF: PES: DMF/20:0:80 produce the highest selectivity (1.3086 GPU) while blending ratio of PVDF: PES: DMF/10:10:80 exhibited the least selectivity. Moreover, the morphological elucidation revealed the presence of pores for every cross-section composite membrane and this aids the permeability properties of the membrane aggregates at different blending ratio. Also, the FTIR results showed nearly similar functional group characteristic

MICROWAVE IRRADIATION OPTIMIZATION FOR EFFICIENT LIGNIN REMOVAL FROM COCOA SHELL WASTE USING ALKALI

This paper reports a study to determine the optimum conditions of microwave in assisting alkali treatment for removing lignin from cocoa shell waste (CSW). The CSW was mixed with 5% of NaOH solution at the ratio of 1: 10 of weight to volume of the alkaline before being irradiated in a microwave oven. Various microwave powers (200-400 W), temperature settings (60-80 °C) and irradiation times (10-20 min) were tested on 15 samples set by the Box-Behnken design. The lignin removal was analysed using a 72 % sulfuric acid treatment method. A quadratic equation was employed to the response surface and statistical analysis conducted to confirm the adequacy of the model. The plots show that the optimum microwave conditions are 400 W, 76 °C and 19 min, which were capable to remove 86.57% of lignin. Thermogravimetric analysis and micrographs revealed different decomposition temperature of lignin and morphology of extensively-pored surface of treated CSW, respectively. ABSTRAK: Kajian ini adalah berkaitan penentuan keadaan optimal ketuhar gelombang mikro bagi membantu menyingkirkan lignin daripada sisa kulit biji koko (CSW) menggunakan rawatan alkali. CSW dicampurkan dengan larutan NaOH 5 % pada nisbah 1:10 berat kepada isipadu larutan alkali sebelum campuran dipanaskan ke dalam ketuhar gelombang mikro. Pelbagai keadaan ujian dibuat pada ketuhar gelombang mikro seperti tenaga (200-400 W), suhu ketuhar (60-80 °C) dan masa pemanasan (10-20 min) ke atas 15 sampel mengikut reka bentuk statistik Box-Behnken. Kadar penyingkiran lignin ditentukan dengan menggunakan kaedah rawatan larutan asid sulfurik berkepekatan 72 %. Persamaan kuadratik telah digunakan ke atas permukaan respon dan analisis statistik telah dilakukan bagi memastikan kesesuaian model. Plot-plot menunjukkan keadaan optima ketuhar gelombang mikro adalah pada 400 W, 76 °C dan 19 min iaitu berupaya menyingkirkan sebanyak 86.57% lignin. Analisis thermogravimetri dan mikrograf masing-masing menunjukkan perbezaan suhu penguraian lignin dan morfologi permukaan CSW yang dirawat didapati berliang dengan banyaknya

Mechanical properties of poly(lactic acid) compounded with recycled tyre waste/graphene nanoplatelets nanocomposite

This study reports the binary blend of poly(lactic acid) (PLA) with recycled tyre waste (RW) with different compositions. The effect of graphene nanoplatelets (GNP) on the RW/PLA in terms of mechanical and morphology of nanocomposites have been investigated. The sample was prepared by twin-screw extruder with a die of 25 mm width and 0.5 mm thickness. Results show that incorporation of GNP at 1, 2 and 3 phr improves the tensile properties of the RW/PLA blend. It was found that the surface morphologies by Scanning Electron Microscope (SEM) show that the loading of GNP in nanocomposites decreases the formation of void and pores in the blend system

Increasing frailty is associated with higher prevalence and reduced recognition of delirium in older hospitalised inpatients: results of a multi-centre study

Purpose: Delirium is a neuropsychiatric disorder delineated by an acute change in cognition, attention, and consciousness. It is common, particularly in older adults, but poorly recognised. Frailty is the accumulation of deficits conferring an increased risk of adverse outcomes. We set out to determine how severity of frailty, as measured using the CFS, affected delirium rates, and recognition in hospitalised older people in the United Kingdom. Methods: Adults over 65 years were included in an observational multi-centre audit across UK hospitals, two prospective rounds, and one retrospective note review. Clinical Frailty Scale (CFS), delirium status, and 30-day outcomes were recorded. Results: The overall prevalence of delirium was 16.3% (483). Patients with delirium were more frail than patients without delirium (median CFS 6 vs 4). The risk of delirium was greater with increasing frailty [OR 2.9 (1.8–4.6) in CFS 4 vs 1–3; OR 12.4 (6.2–24.5) in CFS 8 vs 1–3]. Higher CFS was associated with reduced recognition of delirium (OR of 0.7 (0.3–1.9) in CFS 4 compared to 0.2 (0.1–0.7) in CFS 8). These risks were both independent of age and dementia. Conclusion: We have demonstrated an incremental increase in risk of delirium with increasing frailty. This has important clinical implications, suggesting that frailty may provide a more nuanced measure of vulnerability to delirium and poor outcomes. However, the most frail patients are least likely to have their delirium diagnosed and there is a significant lack of research into the underlying pathophysiology of both of these common geriatric syndromes

Poly(Lactic Acid) (PLA)/Acrylonitrile Butadiene Styrene (ABS) with Graphene Nanoplatelet (GNP) Nanocomposites

A melt blending of poly(lactic acid) (PLA)/acrylonitrile-butadiene-styrene (ABS) with 30:70 PLA:ABS was prepared by a twin screw extruder with a die of 25 mm width and 0.5 mm thickness with various loadings of graphene (0–1.0 wt.%). The PLA/ABS blends were evaluated by mechanical, morphology, thermal and interaction of the components of the blend. Results show the incorporation of graphene nanoplatelet (GNP) improved the tensile and modulus properties. Nevertheless, it was observed that at higher GNP loadings i.e. 0.6–1.0 wt.%, both tensile and modulus properties showed a decreasing trend. It was also found that the thermal stability for the blend slightly improved when graphene presence in the blend

Preparation and characterization of poly(lactic acid)/linear low density polyethylene/recycled tire waste/graphene nanocomposites

Biobased polymer nanocomposites are a separate class of materials created by the inclusion of nanoparticles into polymer matrix composites. In comparison to ordinary composites, these materials have superior mechanical, electrical, thermal, and barrier characteristics, as well as exceptional microstructures, which have attracted global interest. For toughness modification, poly(lactic acid) (PLA) is commonly toughened with low-modulus polymers such as linear low-density polyethylene (LLDPE). Due to environmental concerns, recycled tire waste (RW) was included in a binary blend of PLA and LLDPE and reinforced with graphene nanoplatelets (GNP). The polymer resins, RW and GNP were melt blended in a twin-screw extruder at 60 rpm for 15 min. The blends were then characterized for chemical changes, thermal transitions and thermal degradation. Due to the presence of platelets, it was discovered that the 40/50/10/5 (PLA/LLDPE/RW/GNP) nanocomposite exhibited the maximum thermal degradation temperature. Thermal transitions were observed in all nanocomposites without any appreciable chemical changes

Statistical study on the interaction factors of polypropylene-grafted-maleic anhydride(PP-g-MA) with graphene nanoplatelet (GNP) at various poly (lactic acid)/polypropylene (PLA/PP) blebds ratio.

This paper reports the effects of polypropylene-graft-maleic anhydride (PP-gMA) and graphene nanoplatelet (GNP on tensile stress of various PLA/PP weight ratio. The PLA/PP blends prepared with the ratio 70/30, 80/20, and 90/10 with the addition of PP-g-MA (1 to 5 phr) and GNP (1 to 3 phr) by using an injection molding machine. The tensile stress (MPa) was analyzed based on 11 runs of full factorial design. The results showed that the tensile stress of PLA/PP blends gradually increased after the addition of PP-g-MA and GNP. There is a relationship between PP-g-MA and GNP which causes a positive impact on the mechanical properties of PLA/PP blends. The optimum tensile stress of 50.06 MPa achieved at the ratio of 90/10 blends with 5 phr of PP-g-MA and 3 phr of GNP.Keywords: poly(lactic acid)(PLA); polypropylene (PP); graphene nanoplatelets (GNP