Acrylonitrile Butadiene Styrene Research Articles

Identification of microplastic content in milkfish ponds in Lontar Village, Serang Regency

Microplastics measuring < 5 mm can easily enter the fish's body through the respiratory system and digestive system. The aim of this research is to calculate the abundance of microplastics and determine the types contained in the bodies of milkfish, water and sediment in the Lontar Village Pond, Serang Regency. There are 6 stations, 4 fish samples were taken from each station, water samples were taken using a plankton net and sediment samples were taken using individual pipes at each station. The number of fish samples was 24 fish, meat, intestine, stomachs and gills were taken. Fish organs were destroyed using 10% KOH. Samples were incubated for 24 hours until the organic material was destroyed. Then filtered using Whattman No 42, and dried using an oven at 60ºC for 1 hour. Likewise, filtering of water and sediment samples is carried out. The types of microplastics found were fragments, fibers and films. The highest abundance was in the gills and intestines with an abundance of 11 per individual. The highest abundance of microplastics in the water in Lontar Village ponds is the fragment type with a total of 5 per/20 mL at station 3 and the film type with a total of 5 per/20 mL at station 6 and in the milkfish pond sediments of Lontar Village the highest abundance of microplastics is 1 per/25 gr. The types of polymers found in the digestive tract of milkfish are Polycarbonate (PC), Acrylonitrile butadiene styrene (ABS), Latex, Polystyrene (PS), Nylon, and Polytetrafluoroethylene (PTFE).Keywords: Aquaculture; Lontar; Microplastics; Milkfish

Towards Design Optimization of Compliant Mechanisms: A Hybrid Pseudo-Rigid-Body Model-Finite Element Method Approach and an Accurate Empirical Compliance Equation for Circular Flexure Hinges.

Innovative designs such as morphing wings and terrain adaptive landing systems are examples of biomimicry and innovations inspired by nature, which are actively being investigated by aerospace designers. Morphing wing designs based on Variable Geometry Truss Manipulators (VGTMs) and articulated helicopter robotic landing gear (RLG) have drawn a great deal of attention from industry. Compliant mechanisms have become increasingly popular due to their advantages over conventional rigid-body systems, and the research team led by the second author at Toronto Metropolitan University (TMU) has set their long-term goal to be exploiting these systems in the above aerospace applications. To gain a deeper insight into the design and optimization of compliant mechanisms and their potential application as alternatives to VGTM and RLG systems, this study conducted a thorough analysis of the design of flexible hinges, and single-, four-, and multi-bar configurations as a part of more complex, flexible mechanisms. The investigation highlighted the flexibility and compliance of mechanisms incorporating circular flexure hinges (CFHs), showcasing their capacity to withstand forces and moments. Despite a discrepancy between the results obtained from previously published Pseudo-Rigid-Body Model (PRBM) equations and FEM-based analyses, the mechanisms exhibited predictable linear behavior and acceptable fatigue testing results, affirming their suitability for diverse applications. While including additional linkages perpendicular to the applied force direction in a compliant mechanism with N vertical linkages led to improved factors of safety, the associated increase in system weight necessitates careful consideration. It is shown herein that, in this case, adding one vertical bar increased the safety factor by 100N percent. The present study also addressed solutions for the precise modeling of CFHs through the derivation of an empirical polynomial torsional stiffness/compliance equation related to geometric dimensions and material properties. The effectiveness of the presented empirical polynomial compliance equation was validated against FEA results, revealing a generally accurate prediction with an average error of 1.74%. It is expected that the present investigation will open new avenues to higher precision in the design of CFHs, ensuring reliability and efficiency in various practical applications, and enhancing the optimization design of compliant mechanisms comprised of such hinges. A specific focus was put on ABS plastic and aluminum alloy 7075, as they are the materials of choice for non-load-bearing and load-bearing structural components, respectively.

Biomechanical Analysis of Pedicle Screw Reinsertion Along the Same Trajectory in a Validated 3D-Printed Synthetic Bone Model

To investigate the biomechanical properties of pedicle screw reinsertion along the same trajectory in a previously validated synthetic bone model. Twenty identical acrylonitrile butadiene styrene models of lumbar vertebrae were three-dimensional-printed. Screws were placed in the standard fashion into each pedicle. Models were separated into 2 equal groups, control and experimental. Experimental group screws were completely removed from their testing block and reinserted once. All screws in both groups were then forcibly removed. Continuous torque monitoring was collected on screw insertion torque (IT), removal torque, and reinsertion torque. Pullout strength (PO), screw stiffness (STI), and strain energy (STR) were calculated. There was no significant difference between control and experimental groups for PO (P=0.26), STI (P=0.55), STR (P=0.50), or IT (P=0.24). There was a significant decrease in reinsertion torque (54.5 N-cm±8.2 N-cm) from control IT (62.9 N-cm±8.4 N-cm, P=0.045) and experimental IT (67.5 N-cm±7.6 N-cm, P=0.0026). Strong correlations (Pearson's r>0.80) were seen between control IT against STR and PO, between each of the experimental torque measurements, and between experimental PO and STI. Despite a significant decrease in insertion torque, there is no significant loss of pedicle screw performance when a screw is removed and reinserted along the same trajectory.

Correlation between AFM characterizations and dynamic mechanical testing to assess the ductile-to-brittle transition during ABS photodegradation

The extensive use of Acrylonitrile Butadiene Styrene (ABS) raises challenges due to its vulnerability to oxidative degradation, primarily impacting its mechanical behavior. Photodegradation appears to be the pivotal driver in this degradation process. The main aim of the present study is to provide a comprehensive approach to the underlying mechanisms governing the transition from ductile to brittle behavior in ABS after exposure to UV-induced photodegradation. This study thus focuses on the multiphase nature of ABS, wherein polybutadiene (PB) nodules are dispersed within a matrix of styrene-acrylonitrile. Dynamic mechanical tensile tests have been employed to highlight aged layer mechanical impact by blocking the dissipative response of the matrix and applying a homogenous stress field, while atomic force microscopy (AFM) has been used to characterize the local mechanical properties of ABS finely. The evolution of global mechanical properties has been correlated with changes in microstructural behavior. One of the main contributions of the present work is the correlation between the formation of brittle layers with the brittle state of aged ABS. Mechanical testing using dynamical tensile test revealed a critical aging time marking the transition from a ductile to a brittle state of the 450 µm thick samples. Chemical analysis using infrared spectroscopy revealed evolutions in the material composition, especially in the carbonyl, hydroxyl, and PB unsaturation groups. Distinct thin oxidized layers on each exposed surface were observed using optical microscopy. Finally, AFM analysis on the exposed surface shows the stiffening of PB nodules, indicating the formation of brittle thin layers due to oxidation causing an apparent fragile behavior of ABS.

Towards personalized microfluidics: 3D printing of high-performance micropumps by control and optimization of fabrication-induced surface roughness

Additive fabrication technologies are very attractive for use in the realization of customized medical diagnostic and point-of-care devices in the rapidly growing field of personalized healthcare. However, non-idealities in additive manufacturing processes, such as the enhanced roughness that is inherent to many such processes, limit the use of these fabrication technologies in real products. In this work, the effect of additive fabrication-induced surface roughness on fluid flow within material extrusion (MEX) 3D-printed microfluidic devices is modeled and experimentally validated. An optimization process to eliminate such effects in functional 3D-printed devices is developed. By the resulting careful model-driven optimization, high-performance printed glass and Acrylonitrile butadiene styrene (ABS) valveless micropumps are demonstrated in this work for the first time. Water flow rates of 210 µl min−1 and 140 µl min−1 for the ABS and the glass micropumps respectively, and a maximum working backpressure of 978 Pa at an actuation signal of 68 Hz and 120 Vpp are achieved, attesting to the viability of additive fabrication to realize functional microfluidic devices.

An Investigation on the Presence and Risk Assessment of Microplastics in Quilon Beach, South West Coast of India

Microplastics (MPs) are the most serious emerging pollutant around the globe. Anthropogenic activities are the major contributor of MPs in beach sediments. MPs are widely distributed along beaches and pose a serious threat to the marine food chain including human health. The present study aims to investigate, for the first time, the occurrence, quantification of abundance and risk assessment of MPs in Quilon beach, India and also identifies the potential sources along with the assessment of degree of MPs contamination using Pollution load index (PLI) and Pollution Hazard index (PHI) parameters. Sampling was conducted in dry season in the beach. A total of thirty-three samples were collected establishing a 20m grid pattern along the study area. MPs of size range 5mm - < 0.25mm were considered. The average abundance of MPs in the study area is 3145±2515 MPs/kg of sand. Polyester (PES), Acrylonitrile butadiene styrene (ABS) are the major polymer types in the study area. Fibre was the most dominant shapes. The frequent colours found were white and transparent. MPs of size <0.25mm were the most common of all the samples. Anthropogenic activities including sewage effluents, fishing and tourism activities might be the main sources of MPs pollution in this area.

Measuring thermomechanical response of large-format printed polymer composite structures via digital image correlation

Large-format additive manufacturing (LFAM) is a branch of additive manufacturing (AM) research with the ability to create large structures typically measuring several meters in scale. LFAM is advantageous for tooling applications, not only because it offers the ability to create complex geometries not easily made using subtractive manufacturing processes, but the cost savings of pelletized feedstock used by these systems result in larger parts printed at faster speeds than traditional AM systems. Fiber reinforced polymer (FRP) is a commonly used feedstock material in LFAM structures because it reduces the distortion experienced during printing. However, FRP introduces highly anisotropic thermomechanical properties and contributes to a nonhomogeneous microstructure that can result in critical distortion of dimensions during tooling. Measuring the global thermomechanical response of LFAM structures requires a more representative method that accounts for not only anisotropic properties but also the nonhomogeneous nature of the final part. This is where traditional techniques to measure thermomechanical response, such as thermomechanical analysis (TMA), fall short as they assume homogeneity. This study evaluated the coefficient of thermal expansion (CTE) of LFAM structures as measured by TMA as compared to a novel digital image correlation oven (DIC Oven) system. The LFAM structures were made from 20 % by weight carbon fiber reinforced acrylonitrile butadiene styrene (CF-ABS). TMA measurements showed significant variations in CTE across a single LFAM bead, confirming the need for a global technique that captures overall thermomechanical response. The CTE values measured using the DIC Oven compared well to average TMA values obtained from localized measurements across the sample. The DIC Oven was also used to quantify the effects of different layer orientations on thermomechanical properties, which cannot be easily captured using TMA. A predictive model was also developed by using localized TMA values across an LFAM bead to predict the overall thermomechanical response of an LFAM structure.

Multiresponse optimisation and process capability analysis of chemical vapour jet machining for the acrylonitrile butadiene styrene polymer: Unveiling the morphology

Abstract The implementation of three-dimensional (3D) printing technology has culminated in a notable rise in productivity and operational effectiveness for manufacturers. Additive manufacturing (AM) is a manufacturing technology that implies an alteration from the conventional approach of material removal. The fundamental idea underlying the AM technique is the gradual buildup of layers (layer-on-layer accumulation). In conventional approaches, every component can have detrimental implications due to the direct interaction between the tool and the workpiece, leading to the loss of heat through friction. The utilisation of 3D printing as a way to surpass conventional processing methods signifies a novel development in several sectors. This method involves the utilisation of unconventional techniques for the fabrication of components. The primary objective of this research is to investigate the chemical vapour jet drilling technique specifically applied to acrylonitrile butadiene styrene (ABS) materials. The intent is to enhance the surface characteristics, or surface finish (SF), and the dimensional accuracy (DA) of ABS workpieces. An evaluation regarding the reliability, repeatability, as well as preciseness of the vapour jet drilling (VJD) process is conducted via the utilisation of experiment and data analysis. The study employed a Taguchi L9 design of experiments to carry out a series of tests aimed at analysing the implications of three independent variables: pressure, flow rate, and standoff distance. The researchers employed a multiresponse optimisation approach to attain an optimal combination of parameters that resulted in a superior SF with DA. Consequently, the overall appeal of the outcome was reached. The process’s capabilities and dependability were assessed by conducting tests on the substrates at their optimal settings. Surface roughness and circularity were measured at numerous locations on the substrates. The study determined that the process capability indices (C p and C pk) had values over 1.33 for each of the response parameters, with C pk values also exceeding 1. The analysis of histograms and capability indices demonstrates that the VJD method, when conducted under optimised conditions, may be categorised as statistically controlled for the processing of ABS materials.

Experimental investigations into 3D printed hybrid auxetic structures for load-bearing and energy absorption applications

Auxetic structures possess negative Poisson’s ratio due to their unique geometrical configuration. It also offers enhanced indentation resistance, superior energy absorption capacity, excellent impact resistance, higher compressive strength, and other exceptional mechanical properties. In this study, multiple hybrid auxetic structures of three novel geometries have been designed by considering different sets of geometric parameters to numerically investigate the mechanical behaviors of the structures. The energy absorption properties and Poisson’s ratio of the developed hybrid auxetic structures have been measured under quasi-static compressive and bending loads. The numerically optimized structures from each of the three different geometries have been fabricated of acrylonitrile butadiene styrene using fused deposition modeling. Additionally, the simulated results have been experimentally validated. The validation studies have shown close agreement of their performances with the simulated results. Finally, comparative analyses of energy absorption performances have also been performed to select the most suitable structure for impact-resistant applications. Moreover, it has been observed that structure-2 exhibits superior performance in terms of maximum load-bearing capacity of 3395 N. On the other hand, structure-3 has the maximum energy absorption capacity of 51902 N.mm which is 4.85% higher than structure-1 and structure-2. Similarly, three-point bending test results have revealed that structure-2 performs better in terms of energy absorption capacity (10864 N.mm). Besides this, the effects of loading direction on deformation patterns and mechanical responses of the structures have been observed due to the changes in deformation mechanism. The high-velocity (8 m.s−1) impact test results have also confirmed the suitability of structure-2 for crashworthiness applications. The comparative findings derived from this study contribute significantly in developing lightweight, energy-absorbent, and impact-resistant auxetic core-sandwiched structures for civil, defense, and automobile sectors.

Electrophysical Characteristics of Acrylonitrile Butadiene Styrene Composites Filled with Magnetite and Carbon Fiber Fillers.

With the rapid development of wireless communication technologies and the miniaturization trend in the electronics industry, the reduction of electromagnetic interference has become an important issue. To solve this problem, a lot of attention has been focused on polymer composites with combined functional fillers. In this paper, we report a method for creating an acrylonitrile butadiene styrene (ABS) plastic composite with a low amount of conductive carbon and magnetic fillers preparation. Also, we investigate the mechanical, thermophysical, and electrodynamic characteristics of the resulting composites. Increasing the combined filler amount in the ABS composite from 1 to 5 wt % leads to a composite conductivity growth of almost 50 times. It is necessary to underline the temperature decrease of 5 wt % mass loss and, accordingly, the composite heat resistance reduction with an increase in the combined filler from 1 to 5 wt %, while the thermal conductivity remains almost constant. It was established that electrodynamic and physical-mechanical characteristics depend on the agglomeration of fillers. This work is expected to reveal the potential of combining commercially available fillers to construct effective materials with good electromagnetic interference (EMI) protection using mass production methods (extrusion and injection molding).

Quantifying microplastics in sediments of Jinzhou Bay, China: Characterization and ecological risk with a focus on small sizes

Small-sized microplastics (MPs) pose greater ecological toxicity due to their larger surface area, which makes them more likely to act as carriers for other pollutants and to be ingested by aquatic organisms. However, traditional visual analysis often neglects small-sized MPs and their associated ecological risk. This study utilized Laser Direct Infrared (LDIR) spectroscopy and traditional visual analysis to examine MPs in 31 sediment samples from Jinzhou Bay, a typical semi-enclosed bay located at the economic center of Dalian, China. The results showed significant heterogeneity in MP distribution, with averages of 1192 and 2361 items/kg dry weight reported by visual analysis and LDIR spectroscopy, respectively. LDIR spectroscopy identified MPs as small as 10 μm, with the majority of MPs (89.21 %) within the 10–250 μm range, and a significant proportion (46.45 %) between 10 and 50 μm among them. However, visual analysis was limited to detecting MPs >50 μm, and significant portions were identified between 50 and 100 μm (49.36 %) and 100–250 μm (31.01 %), missing a substantial fraction of smaller MPs. The predominant polymers identified were polyamide (PA), polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and acrylonitrile butadiene styrene (ABS). LDIR spectroscopy demonstrated a strong positive correlation between MP abundance and clay content, a relationship not observed with traditional visual analysis. The Potential Ecological Risk Index (PERI) indicated that over 87 % of sites posed an extremely high risk according to LDIR spectroscopy, compared to 51 % by traditional visual analysis. These discrepancy underscores the underestimation of ecological risks by traditional methods, particularly for small-sized MPs. High-risk polymers such as polyvinyl chloride (PVC), ABS, and polyurethane (PUR) significantly influenced PERI values. These findings highlight the critical need for precise identification and thorough risk assessment of small-sized MPs in environmental studies and offer insights for understanding of MP vertical migration in aquatic environments, particularly in the context of co-settlement with sediments.

Investigating the reinforcing effect of jute fiber in a PLA & PBAT biopolymer blend matrix for advanced engineering applications: Enhancing sustainability with bioresources

Renewable and biodegradable jute fiber (JF) is strategically incorporated as reinforcement in the poly (lactic acid) (PLA)/ poly (butylene adipate-co-terephthalate) (PBAT) matrix through melt blending. The resulting composites are comprehensively characterized to assess their mechanical properties, thermal stability, and morphological features. Scanning electron microscopy (SEM) is employed to scrutinize the interfacial bonding between the jute fibers and the biopolymer blend matrix. "The impact properties of the PLA/PBAT/JF 15 % composite (PLA/PBAT reinforced with 15 % jute fiber) are compared with a commercially available car dash box. Additionally, a composite fabricated from the recycled car dash box reinforced with 15 % jute fiber is evaluated. The results indicate that the developed composite demonstrates compatibility comparable to Acrylonitrile Butadiene Styrene (ABS) based engineering plastics." This investigation offers insights into the potential of bio-inspired jute fiber reinforcement to enhance the properties of the PLA/PBAT biopolymer blend matrix, thereby increases the scope in engineering applications other than single use application.

Improving the crashworthiness of B-Pillars in side-collisions

The B-pillar plays a crucial element in protecting passengers during side collisions. However, the current technology used in B-pillars is insufficient in providing adequate protection. Therefore, this research aims to investigate ways to improve the crashworthiness of the B-pillars. The study utilizes a 2020 Toyota Yaris due to its prevalence and poor side-crashworthiness and a right body measuring 80cm 60cm 40cm to simulate side collision. The results show that the velocity and acceleration of the upper B-pillar are greater than that of the lower B-pillar, indicating that the welding spot should be placed at the lower end of B-pillars, and the pillars thickness should be increased to enhance side crashworthiness. Furthermore, the study discovers that PVC, when combined with nano-materials, ABS resin, when combined through physical mixing, and SMC materials experience no significant deformation during collision while possessing an incomparably low density. Therefore, the study proposes the use of these stronger materials as an alternative to steel. The cost and feasibility of using these materials in mass production is also analyzed.

Mechanically sustainable and primary recycled thermo-responsive ABS–PLA polymer composites for 4D printing applications: Fabrication and studies

Abstract 3D printing is one of the plastic recycling processes that deliver a mechanically sustainable product and may be used for 4D printing applications, such as self-assembly, sensors, actuators, and other engineering applications. The success and implementation of 4D printing are dependent on the tendency of the shape memory with the action of external stimuli, such as heat, force, fields, light, and pH. Acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) are the most common materials for fused filament fabrication-based 3D printing processes. However, the low-shaped memory tendency on heating and weaker and less rigidity of ABS limit the application domains. PLA is an excellent responsive behavior when the action of heat has high stiffness. The incorporation of PLA into ABS is one of the solutions to tune the shape memory effect for better applicability in the 4D printing domain. In this study, the primary recycled PLA was incorporated into the primary recycled ABS matrix from 5 to 40% (weight%), and composites were made by extrusion in the form of cylindrical filaments for 4D printing. The tensile and shape memory properties of the recycled ABS–PLA composites were investigated to select the best combination. The results of the study were supported by fracture analysis by shape memory analysis, scanning electron microscopy, and optical microscopy. This study revealed that the prepared ABS–PLA-based composites have the potential to be applied in self-assembly applications.

Assessment of microplastic pollution and polymer risk in the sediment compartment of the Limfjord, Denmark

Estuarine sediments intercept and temporarily retain microplastics before they reach the marine seafloor, impacting various organisms, including key commercial species. This highlights the critical need for research on microplastic exposure in these transitional environments. This study provides a detailed assessment of microplastic pollution in the sediment compartment of the Limfjord, a 1500 km2 large Danish fjord, and introduces the Polymer Hazard Index (PHI) as a tool for evaluating polymer-specific risks. Thirteen sediment samples were collected, covering an anthropogenic gradient along the fjord. State-of-the-art methods were applied for extracting and identifying (FPA-μFT-IR imaging) microplastics (10–5000 μm). Our results indicate that microplastic contamination is pervasive across all sampled locations with concentrations ranging from 273 to 4288 particles kg−1, with a predominance of small microplastics (<100 μm). The estimated mass-based concentrations ranged between 2.60 × 104–1.11 × 106 ng kg−1. Overall, we estimated a microplastic stock of 3.8 × 103–1.65 × 105 kg in the surface sediments of the Limfjord, i.e., some 2.5–110 kg km−2. The application of the PHI revealed significant risks associated with specific polymers, such as polyacrylonitrile (PAN) and acrylonitrile butadiene styrene (ABS), underscoring the importance of considering polymer-specific hazards in environmental assessments.

Improving the crashworthiness of bi-tubular architectures with ABS cores under axial loading: Experimental and numerical investigation

In this study, quasi-static axial compression tests were conducted on mild steel bi-tubular architectures with rectangular nested tube (RNT) and square nested tube (SNT) geometries to evaluate their crushing and crashworthiness performance. A multi-criteria decision-making approach was employed to identify the optimal energy-absorbing architecture. The SNT structure, with the smallest gap size between the inner and outer tubes, exhibited the most desirable energy absorption characteristics among the considered cases. Acrylonitrile butadiene styrene (ABS) cores, with either rhombic or square cell configurations, were used to enhance the energy absorption performance of the SNT structure. A finite element model was created to evaluate the responses of the SNT structure filled with ABS cores. The validity of finite element simulations of the ABS cores and optimal architecture under axial compression were confirmed by comparing them with experimental results. The integration of the cores into the nested architecture enhanced crashworthiness performance and contributed to the control of the structure deformation. The SNT structure filled with rhombic ABS core exhibited superior crashworthiness performance compared to the counterpart filled with square core. The energy absorption of nested SNT structures filled with rhombic ABS core can be 116.93% greater than the corresponding non-filled structure. The crashworthiness indices of ABS-filled structures were highly sensitive to the number of cells and wall thickness of the core. A nested architecture with an ABS core could serve as a novel architecture for energy-absorbing devices.

Ultrasonic Welding of Acrylonitrile-Butadiene-Styrene Thermoplastics without Energy Directors.

Ultrasonic welding (USW) of thermoplastics plays a significant role in the automobile industry. In this study, the effect of the welding time on the joint strength of ultrasonically welded acrylonitrile-butadiene-styrene (ABS) and the weld formation mechanism were investigated. The results showed that the peak load firstly increased to a maximum value of 3.4 kN and then dropped with further extension of the welding time, whereas the weld area increased continuously until reaching a plateau. The optimal welding variables for the USW of ABS were a welding time of 1.3 s with a welding pressure of 0.13 MPa. Interfacial failure and workpiece breakage were the main failure modes of the joints. The application of real-time horn displacement into a finite element model could improve the simulation accuracy of weld formation. The simulated results were close to the experimental results, and the welding process of the USW of ABS made with a 1.7 s welding time can be divided into five phases based on the amplitude and horn displacement change: weld initiation (Phase I), horn retraction (Phase II), melt-and-flow equilibrium (Phase III), horn indentation and squeeze out (Phase IV) and weld solidification (Phase V). Obvious pores emerged during Phase IV, owing to the thermal decomposition of the ABS. This study yielded a fundamental understanding of the USW of ABS and provides a theoretical basis and technological support for further application and promotion of other ultrasonically welded thermoplastic composites.

3D printing of continuous metal fiber-reinforced recycled ABS with varying fiber loading

PurposeThe current study aims to develop a 3D-printed continuous metal fiber-reinforced recycled thermoplastic composite using an in-nozzle impregnation technique.Design/methodology/approachRecycled acrylonitrile butadiene styrene (RABS) plastic was blended with virgin ABS (VABS) plastic in a ratio of 60:40 weight proportion to develop a 3D printing filament that was used as a matrix material, while post-used continuous brass wire (CBW) was used as a reinforcement. 3D printing was done by using a self-customized print head to fabricate the flexural, compression and interlaminar shear stress (ILSS) test samples to evaluate the bending, compressive and ILSS properties of the build samples and compared with VABS and RABS-B samples. Moreover, the physical properties of the samples were also analyzed.FindingsUpon three-point bend, compression and ILSS testing, it was found that RABS-B/CBW composite 3D printed with 0.7 mm layer width exhibited a notable improvement in maximum flexural load (Lmax), flexural stress at maximum load (sfmax), flex modulus (Ef) and work of fracture (WOF), compression modulus (Ec) and ILSS properties by 30.5%, 49.6%, 88.4% 13.8, 21.6% and 30.3% respectively.Originality/valueLimited research has been conducted on the in-nozzle impregnation technique for 3D printing metal fiber-reinforced recycled thermoplastic composites. Adopting this method holds the potential to create durable and high-strength sustainable composites suitable for engineering applications, thereby diminishing dependence on virgin materials.

Optimization of physical and mechanical properties of PC/ABS/PMMA blends by mixture design approach

AbstractThis study aims to investigate the recycling of end‐of‐life computer plastics, focusing on polycarbonate (PC) and acrylonitrile–butadiene–styrene (ABS) copolymer, which constitute a significant portion of collected computers. Through differential scanning calorimetry and infrared spectroscopy analyses, the properties of raw PC, ABS and poly(methyl methacrylate) (PMMA) were evaluated. Various blends of PC and ABS were prepared, incorporating different percentages of recycled PMMA as a cost‐effective coupling agent. These blends were processed through melt compounding using a contra‐rotating twin‐screw extruder and subsequently shaped by injection molding. An experimental mixture design was applied to evaluate the mechanical and physical properties of the composite materials, including melt flow index, hardness, flexural strain at break and Charpy impact strength. The results of the desirability analysis indicated that the optimal blend for achieving a balance between mechanical and physical properties consists of a high PC content (approximately 80% or more), a low ABS content (less than 20%) and less than 5% recycled PMMA. © 2024 Society of Chemical Industry.

Effect of additively manufactured polymeric inserts on impact response of construction safety helmets

Purpose Struck-by accidents (i.e. being hit by a falling object) are a leading cause of traumatic brain injuries in the construction industry. Despite the critical role of hard hats in minimizing such injuries, their overall design has not appreciably changed in decades. Therefore, this study aims to explore the potential benefits of modifying commercially available hard hat designs by incorporating a compliant cantilever and a sacrificial, energy-absorbing structure to enhance their protective capabilities against impacts. Design/methodology/approach This study involved conducting experimental impact tests to obtain the head acceleration attenuation using hard hats with a variety of compliant cantilever lattice insert designs. These lattice inserts were additively manufactured using three polymeric materials, including polylactide (PLA), acrylonitrile butadiene styrene, high-impact polystyrene and three porosity levels. A Hybrid III head/neck assembly was fitted with each hard hat design, and experimental drop tests were conducted using a 1.8-kg steel impactor dropped from 1.83 m. The maximum acceleration and head injury criterion (HIC) values were obtained for each test. Findings Analysis of variance revealed that HIC was significantly reduced for all lattices with 56% porosity (p &lt; 0.023) compared to the control (unmodified) hard hat. The most effective insert was found to be a PLA insert with 56% porosity, which reduced the HIC value by 38% compared to the control (unmodified) hard hat, with a statistically significant p-value of 0.018. Originality/value The data present in this study reveals that simple and inexpensive modifications can be made to existing hard hat designs to reduce injury risk from overhead impacts.