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The hybrid single shot method is an innovative manufacturing technique that allows thermoset composite sheets to be formed and cured while they are also bonded into an injected thermoplastic body all in a single integrated operation. This integration concept is complex in nature but promising to overcome the drawbacks of the traditional procedures for manufacturing such multi-material structures by reducing the cycle time, energy consumption, and cost of the required tools and machinery. In this study, CF/Epoxy prepreg sheets are selected as the inserted material which is then later deformed and bonded to an injected body made of a polypropylene compound. The bonding between these two dissimilar materials is mostly achieved by taking the advantages of the melt penetration and the tackiness of the prepreg sheet. Therefore, an experimental study is here designed and carried out to evaluate the bonding conditions of the final hybrid parts regarding several influential process parameters. To better monitor the process and analyze the physics behind this integration, a set of real-time process variables are measured and analyzed using an instrumented experimental setup. The results show that the pre-heating time has the largest effect on the bonding strength, and the best combination of the deformation and bonding strength is achieved when the cavity pressure and temperature are at the highest level compared to the other experiments. The maximum bonding strength attained in the optimum process settings was 6.8 MPa which shows a 51% improvement compared to the average value of the other experiments.

Recent advancements in instrumentation and the emergence of industrial IoT solutions have created new possibilities to collect data in injection molding processes. Although many approaches have bee...

A series of nitrogen-doped carbons (NCs) were prepared by the pyrolysis (300–900 °C) of crystalline polyazomethine (PAM) synthesized via a facile condensation reaction in methanol solvent. The controlled solvent evaporation resulted in PAM crystals in the form of nanosheet clusters with a sheet thickness of ~50 nm. Such architecture was maintained after pyrolysis, obtaining porous CNs of high specific surface areas of up to 700 m2/g. The resulting NCs were used as absorbents to remove aromatic Rhodamine B from water. The NC that pyrolyzed at 750 °C exhibited the highest adsorption capacity (0.025 mg/mg), which is attributed to its high surface area and surface condition.

Delignified wood (DW) is natural wood’s cellulosic skeleton. It has highly ordered anisotropic architecture, permitting solute accessibility to modify its abundant interior surfaces. Herein, we demonstrate a facile method to coat polydopamine (PDA) conformally on DW’s interior surfaces. The PDA layer not only introduced heteroatom (N), but also facilitated the generation of silver particles by in situ reduction. The prepared DW skeletons were freeze-dried and pyrolyzed at 850/1200 °C to create carbonized DW (CDW) and then embedded in the epoxy matrix to prepare a composite for the application of electromagnetic interference (EMI) shielding. It was found that the PDA coating converted to a highly conductive carbon species on the surface of a DW-derived carbon scaffold. As a result, the PDA modification increased the electrical conductivity (EC) of the plain epoxy/CDW from 0.32 to 0.46 S/m, and accordingly the EMI shielding effectiveness (SE) increased from 18.2 dB for epoxy/CDW to 24.0 dB for epoxy/CDW-PDA, and 30.6 dB for epoxy/CDW-Ag. This work provides a facile and universal methodology to enhance the EC and EMI SE performance of open-porous carbon.

Fluorescent graphene quantum dots (GQDs) prepared from low-cost and sustainable precursors are highly desirable for various applications, including luminescence-based sensing, optoelectronics, and ...

Fullerene-based low-dimensional (LD) heterostructures have emerged as excellent energy conversion materials. We constructed van der Waals 1T-MoS2/C60 0D-2D heterostructures via a one-pot synthetic approach for catalytic hydrogen generation. The interfacial 1T-MoS2-C60 and C60-C60 interactions as well as their electrocatalytic properties were finely controlled by varying the weight percentages of the fullerenes. 1T-MoS2 platforms provided a novel template for the formation of C60 nanosheets (NSs) within a very narrow fullerene concentration range. The heterostructure domains of 1T-MoS2 and C60 NSs exhibited excellent hydrogen evolution reaction (HER) performances, with one of the lowest onset potentials and ΔGH* values for LD non-precious nanomaterials reported to date.

Although the mass production of cellulose nanocrystals (CNC) shows the possibility of their use in scalable nanocomposite manufacturing, the low compatibility between the CNC-hydrophobic matrix and...

Polyurethanes are among the top six polymers produced in the world and are widely used in the automotive, furniture, construction and appliance industry for their light weight, impact resistance, and insulating properties. However, the use of hazardous diisocyanates used in polyurethane formulations has led many to search for more sustainable alternatives. The lignin component of biomass has been targeted to replace the often toxic and petroleum-derived precursors to polymer synthesis in support of the biorefinery concept where natural materials are used as the feedstock for commodity plastics. The use of lignin is often hampered due to its low reactivity, heterogeneity and the necessity of employing extensive purification and/or functionalization measures to ensure materials are of comparable quality. In this report, a unique method is presented for the synthesis and processing of a non-toxic, non-isocyanate polyurethane foam utilizing unmodified Kraft lignin and a biobased curing agent. Raw Kraft lignin is functionalized with green organic carbonates and a non-toxic approach is taken to solubilize the precursors with a curing agent from renewable fatty acids enabling rapid gel-times. For the first time, a NIPU foam from lignin is synthesized while the structure–property relationship of different reaction mixtures is studied demonstrating shape memory capacity and 100% biobased carbon content.

Lithium-ion batteries (LIBs) are dominant electrochemical energy storage systems in rapidly growing electronic markets. However, the conventional anode and cathode materials have limited specific capacity and quickly approach their theoretical limit. Hence, alternate battery chemistry beyond LIBs is required. Lithium-sulfur (Li-S) batteries are noteworthy energy storage systems due to their high theoretical capacity (1672 mAh/g), high theoretical energy density (2600 Wh/kg), and low cost of raw materials. Unfortunately, commercialization of Li-S batteries is hindered by the low electronic conductivity of sulfur and intermediate polysulfides, polysulfide dissolution and shuttle effect, volume expansion of elemental sulfur during the charge/discharge process, and lithium dendrite growth at the anode side. To address these challenges, various strategies such as modification of sulfur hosts, electrolyte optimization, and separator modifications have been employed. Initially, researchers encapsulated sulfur in various carbonaceous materials to mitigate the polysulfide shuttle. Later, a new active material, called sulfurized polyacrylonitrile (SPAN), was developed to mitigate the polysulfide shuttle and extend the life cycle of Li-S batteries. The main advantage of the SPAN over elemental sulfur is that it is more effective in mitigating polysulfide dissolution and shuttling due to the presence of the C−S bonds, consequently preventing the loss of active material. On the other hand, due to the limited number of binding sites in the SPAN structure, the sulfur content of SPAN materials is limited to 40 – 44 wt.%. To compete with the state-of-the-art LIBs, the Li-S batteries should provide an areal capacity of >5 mAh/cm2, corresponding to a sulfur loading of >5 mg/cm2. Realizing such a high S loading using 2D planar current collectors (e.g., aluminum foil) without compromising specific capacity and cycling stability is practically unrealistic. Using synthetic materials (e.g., graphene foam, graphene aerogel, metal-organic framework), three-dimensional (3D) electrode architectures with high SPAN loading and efficient electron and ion conductive pathways have been constructed. However, preparing these 3D electrodes mainly involves synthetic raw materials, harsh chemicals, and costly fabrication processes. Porous carbon frameworks derived from biomass, which are plant-based materials derived from nature, are alternative candidates. Biomass structures with interconnected channels over multiple length scales can provide a natural 3D template for electrochemical energy storage systems. In this study, we took advantage of the inherent porous structure of natural wood and engineered 3D frameworks using a delignification/low-temperature pyrolysis approach. A block of Balsa wood was sliced into thin sheets parallel to the tree growth direction. To facilitate the permeation of active material into the cellular structure, we first subjected the wood to a facile chemical treatment to remove lignin and hemicellulose. The delignified wood (DW) was then converted to an ultra-lightweight carbonized DW (CDW) scaffold using a low-temperature pyrolysis approach. To prepare CDW scaffolds, the DW sheets were pyrolyzed at 500, 600, 700, and 1000 °C. Continuous electron transport through the CDW conductive network and ion transport along the highly porous cellular body makes intrinsic and effective charge transfer through the CDW scaffold. SPAN active material was synthesized by pyrolyzing a mixture of elemental S and polyacrylonitrile under nitrogen flow and then using it to prepare an aqueous slurry of SPAN, CMC, and carbon black with a mass ratio of 70:15:15. To prepare the cathodes, CDWs were cut into squares with an area of 1.00 ± 0.05 cm2, dipped into a beaker of SPAN slurry, and kept under a vacuum. SPAN-impregnated free-standing electrodes (SPAN@CDW) were dried and utilized for electrochemical studies. The unique design of the SPAN@CDW electrode, wherein the interconnected pathways run in three-dimension, ensured effective electron and ion transport within the cathode. Thus, SPAN@CDW cathodes exhibited an excellent rate capability, with discharge capacities >1000 mAh/gs at 1C (1672 mA/g). The electrode with CDW pyrolyzed at 600 °C, and S loading of ~2 mg/cm2 exhibited a high specific capacity of ~1350 mAh/gs after 500 cycles at 0.1C, indicating good cycling stability. We also demonstrated the fabrication of SPAN@CDW electrodes with a high S loading of ~12.3 mg/cm2, which could deliver a high areal capacity of ~15.1 mAh/cm2 at 0.1C.

The growing population and increasing demands for energy are overwhelming our supply of fossil fuels and limiting the availability for future generations. Technologies for energy storage devices are emerging to replace conventional fuel-based technologies to meet emissions goals set by world governments and the rapid electrification of the transportation sector. Lithium-ion batteries (LIBs) are widely used for energy storage in devices across many commercial applications. LIB electrodes are continuously evolving due to demands for higher energy density and long cycling life. Among the recent developments in anode electrode materials, silicon (Si) is regarded as the most promising replacement for graphite due to its high theoretical specific capacity (~4200 mAh g-1), which is over 10 times greater than that of conventional graphite anodes (~372 mAh g-1). Despite the advancements, persisting challenges hinder the commercialization of Si for LIB anodes. Si-based electrodes are susceptible to rapid degradation due to the large volume change (approx. 400%) of Si particles during lithium insertion and extraction. The repeated volume change leads to the pulverization of the Si material, ultimately leading to decreased cycling stability from the loss of contact with the current collector. To overcome this obstacle, 3-dimensional porous and hollow nanostructures have been employed to provide sufficient void space to accommodate the volume change during electrochemical cycling. However, with the demands for material cost-reduction from industry, Si structures' strategic engineering must be cost-effective for commercial viability. Our team has developed a patent-pending cost-effective, scalable, and green methodology to use bio-renewable templates to synthesize a 3-dimensional Si architecture, called Si nano-quills (SiNQs). We innovated a two-step, cost-effective process that yields SiNQs with a porous morphology and hollow interior structure. First, in a scalable sol-gel process, silica gel particles were prepared using commonly available low-cost chemicals. The unique mesoporous SiNQ morphology was engineered using surfactant-modified cellulose nanocrystals as a bio-renewable sacrificial template. The templates were removed via thermal treatment to form silica nanoparticles. These particles, called silica nano-quills (SilicaNQs), possess a 3-dimensional bulk structure comprised of hollow quill-like arms and a high degree of porosity. In the second step, we employed a low-temperature magnesiothermic reduction method to convert SilicaNQs into SiNQs with a relatively large surface area. Anode electrodes were fabricated using SiNQs as the active material for electrochemical testing. The slurry was prepared using the active material, carbon black, and PVDF with a mass ratio of 60:20:20 coated onto an ion-permeable Bucky Paper (BP, a flexible and conductive paper made of carbon nanotubes). The 2032-type coin cells were assembled for battery testing using SiNQ electrodes (with an active mass loading of 1 mg cm-2) and a lithium metal chip as the counter electrode. The coin cells were cycled at a current rate of 0.1C (420 mA g-1) over the potential range of 0.01 – 1.0 V at room temperature. The SiNQ anode offered superior battery capacity retention of 73% of the initial reversible capacity of 963 mAh g-1 after 220 cycles. In comparison, batteries fabricated from the Mg reduction of commercially available mesoporous silica, SBA-15, offer capacity retention of only 52.6% after 100 cycles. The SiNQ precursor is engineered to possess porous walls with a superior BET surface area (1265 m2 g-1) compared to SBA-15 (550 m2 g-1). After Mg reduction, the SiNQs retain a BET surface area of 232 m2 g-1, whereas the surface area of reduced SBA-15 is 74 m2 g-1. The superior performance of SiNQs is due to their unique morphology that offers high surface area and porosity for effective diffusion of lithium ions and more sites for interactions with lithium ions, leading to a higher reversible capacity. Moreover, the porous architecture of SiNQs can effectively mitigate the volume change issue during lithiation and delithiation processes, thus providing a good cycling performance.

One of the biggest challenges of the near future is how to meet the increasing energy demand without any adverse environmental impact. Lithium-Ion batteries (LIBs) are one of the promising alternative energy storage systems to replace conventional non-rechargeable batteries. LIBs are becoming one of the most widely used energy storage devices because of their relatively high specific energy density (~300 Wh/kg), excellent stability over a wide temperature range, and lower cost than other battery systems. Intense research is in progress to increase the capacity of anode electrodes for realizing high-energy LIBs. In this context, silicon (Si) has a great potential to replace commercial graphitic anode active materials mainly due to its high theoretical specific capacity (4200 mAh/g) and low working potential (0.37 to 0.45 V vs. Li/Li+). To harness and maintain a high capacity from Si-based anodes, we must deal with two main challenges: (i) volume changes of Si (>300%) during charging and discharging, which cause pulverization of the material and loss of electrical contact, and (ii) unstable growth of solid-electrolyte interphase (SEI) layer, which can cause early degradation of performance in Si-anode batteries. To overcome these challenges, different approaches have been taken. This includes developing graphite/Si anodes with limited amounts of Si ( To advance the use of Si materials in LIB anodes, we developed a viable technology to create a hybrid silicon-carbon material, called Si@C, in which a soybean-derived carbon cloud protects Si nanoparticles during the battery operation. We employed soybean oil in a scalable oil-in-water emulsion polymerization technique to produce Si-containing polymeric particles. In this method, we emulsified two immiscible solutions. One contains a homogeneous Si mixture in epoxidized soybean oil (ESO), and another contains a uniform dispersion of ball-milled lignin or soyhull powders in water. Citric acid, a crosslinking agent, was used to help polymerize the ESO and integrate carbon-rich lignin/soyhull with polymerized particles. The final Si@C product was achieved by carbonizing the polymerized solid product at 500 °C (under argon) and ball milling to get a fine powder. Several Si@C hybrid materials containing 20 wt.% to 50 wt.% Si were successfully prepared and utilized for anode preparation. Electrodes were made by coating a slurry of Si@C active material, carbon black, and binder with a mass ratio of 60:20:20 onto an ion-permeable Bucky Paper (BP, a flexible and conductive paper made of carbon nanotubes). Anodes with different binding systems were prepared to determine an appropriate binder for Si@C based batteries. The 2032-type coin cells were assembled for battery testing using 1M LiPF6 in EC:DMC in a volume ratio of 1:1 as the electrolyte, Li chips as the counter electrode, and Celgard 2325 as the separator. The coin cells were cycled at a current rate of 0.1C (420 mA/gSi) over the potential range of 0.01 – 1.0 V at room temperature. Battery results showed that Si@C hybrid materials increased the capacity of Si anodes by a factor of >2. At Si mass loading of 1.0 mg/cm2, implementing our carbon cloud approach led to an increase in the discharge capacity of anodes from 0.5 mAh (corresponding to anode with bare Si) to >1.0 mAh (corresponding to anode with Si@C hybrids). Results from battery cycling at 0.1C demonstrated excellent capacity retention of >95% after 130 cycles for anodes prepared using our Si@C active materials. The Si content of Si@C hybrid particles was also found to be an influential factor in the cycling performance of anodes. Finally, we observed that the use of water-based polyacrylic acid (PAA) and carboxymethyl cellulose (CMC) binders improve the electrochemical performance of Si@C based anodes. These water-based binders are ideal for preparing Si-based slurries, and the need for using toxic solvents (e.g., NMP) to prepare slurries can be averted. In conclusion, we innovated a viable technology that uses biomass (soybean oil and soyhulls) to enhance Si-based batteries' performance. We demonstrated that our Si@C materials with a carbon cloud protecting the Si nanoparticles are promising active materials to improve the capacity and cycling stability of LIB anodes.

Facile electron transport and intimate electronic contact at the catalyst-electrode interface are critical for the ideal performance of electrochemical devices such as glucose biofuel cells and biosensors. Here, through a comprehensive experimental-theoretical exploration, we demonstrate that engineering of interfacial properties, including interfacial electron dynamics, electron affinity, electrode-catalyst-adsorbate electrical synergy, and electrocatalytically active surface area, can lead to highly efficient graphene-based electrochemical devices. We selected two closely related but electronically and surface chemically different functionalized graphene analogues-graphene acid (GA) and reduced graphene oxide (rGO)-as the model graphenic platforms. Our studies reveal that compared to rGO, GA is a superior bifunctional catalyst with high oxygen reduction reaction (an onset potential of 0.8 V) and good glucose oxidation activities. Spectroscopic and electrochemical analysis of GA and rGO indicated that the higher carboxylic acid content on GA increases its overall electron affinity and coupled with improved conductivity and band alignment, which leads to GA's better electrochemical performance. The formulation of a heterostructure between GA and samarium oxide (Sm2O3) nanoparticles led to augmented conductivity (lower charge-transfer resistance) and glucose binding affinity, resulting in a further enhanced glucose oxidation activity. The interdimensional Sm2O3/GA heterostructure, leveraging their enhanced glucose oxidation capacity, exhibited excellent nonenzymatic amperometric glucose sensing performance, with a detection limit of 107 nM and a sensitivity of 20.8 μA/μM. Further, a nonenzymatic, membrane-free glucose biofuel cell (with Sm2O3/GA heterostructure as anode and GA as biocathode) produced a power density of 3.2 μW·cm-2 (in PBS spiked with 3 mM glucose), which can function as self-powered glucose sensors with 70 nM limit of detection. The study establishes the potential of interfacial engineering of GA to engage it as a highly tunable substrate for a broad range of electrochemical applications, especially in future self-powered biosensors.

Three compounding methods were compared to determine their effects on the organization of the interphase in nanocomposites of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and cellulose nanoc...

Photocure kinetics of acrylated epoxidized soybean oil (AESO) was studied via photocalorimetry without adding any diluent/comonomer, in the presence of two different photoinitiators, namely, 2,2-dimethoxy phenylacetophenone and 1-hydroxycyclohexyl phenyl ketone. The effect of varying photoinitiator concentration, light intensity, and temperature on the extent of crosslinking was calculated from the ratio of experimentally measured reaction enthalpy to the theoretical enthalpy of reaction (ΔHtheoretical). Photocuring of AESO was observed to be a second-order reaction exhibiting autocatalytic behavior. Nevertheless, due to the occurrence of vitrification, incomplete crosslinking (α ≠ 1) was observed in most curing conditions. Rate constants and activation energies were determined using both nonlinear model-fitting and model-free isoconversional methods. Activation energy, as determined from the model-free isoconversional method, was observed to increase as the reaction proceeded, indicating the shift in cure mechanism from kinetic-controlled to diffusion-controlled. Finally, the reaction termination mechanism was observed to be a combination of second-order and primary radical termination mechanisms.

Conventional leaf springs are simple in design, utilizing multiple metallic bars (leaves) with low geometrical moment of inertia to generate an economical and linear spring rate. In its early form, the leaf-spring was manufactured using metals like steel, but, in modern applications, there exist composite leaves reinforced by advance glass and carbon fibers. Benefits of composite spring designs include: high specific strength, ability to form complex profiles, and possibility of subcomponent consolidation to reduce assembly. Due to the bending characteristics of the leaf spring, the axial load decreases through the beam thickness, reaching a minimum at the neutral surface. Given this fact, a design optimization approach for mono-composite leaf springs is developed considering a hybrid fiber-layup. Initially, a detailed topology optimization is conducted to optimize the geometry of the leaf spring based on the Tsai-Wu failure model. This process yielded a unique spring design which reduced the mass of the spring by 29% compared to the initial non-optimized spring and 80–90% compared to a steel spring. Subsequently, the design is further optimized by replacing low stress, high modulus reinforcement with lower modulus and cost-effective materials to improve overall vehicle mass, efficiency, and operation. The second stage of the optimization based on the hybrid fiber-layup approach resulted in an additional 7% mass reduction. As there is a connection between fuel efficiency and vehicle mass, the significant reduction of spring mass has a positive impact on vehicle fuel consumption and leads to suspension responsiveness gains. Moreover, the possibility of swapping up to 20% of the middle plies reinforcement with commodity plastics demonstrates the cost benefits of the hybrid fiber-layup design approach considering the high cost of carbon and other high-performance reinforcements.

With the rise of Industry 4.0-related technology in the plastic and composite industry, a new wealth of data from the production process is becoming available to manufacturers. The effective utilization of this data towards improving quality and output is therefore of critical importance but requires knowledge of the data that is truly useful and the application of that data to pre-developed models or trained algorithms. Accordingly, in this research, 12 different online data sources in the injection molding process are evaluated to determine their relative degree of importance in predicting variations on final part quality indices, namely part weight, thickness, and diameter. These data are obtained during each injection molding cycle using a data acquisition system connected to eight in-mold sensors and four machine data sources. Three distinct types of perturbations are introduced into the process to challenge the range of detection capacities of these various data sources: shot size variations, material disturbances, and shutdown of the mold cooling system. The resultant curves from these studies are then analyzed for critical values, and partial least square (PLS) regressions performed using the extracted values as predictors and the final part quality indices as responses. Using the standard coefficients from the PLS analysis, rankings of the correlations between the extracted values and final part quality indices are generated, indicating which data sources best detected variations in the final produced parts for each of the three perturbations.

In this study, the effect of epoxidized soybean oil (ESO) on the thermomechanical properties of foams based on epoxidized pine oil (EPO) was investigated. To obtain homogeneity in microstructure, an in-house developed, delayed addition approach was adopted for foaming compositions with polymethylhydrosiloxane (PMHS) while varying ESO content from 10% to 50%. The resulting foams were characterized with respect to microstructure, mechanical and thermal properties. The influence of rheology of blend compositions before gelation on the cell morphology was examined and a prospective approach was proposed for optimality in cell size. Although pure ESO did not cure at room temperature, blending with EPO facilitated processing the foams at room temperature, thereby curtailing the overall energy input in commercially manufacturing such composite systems. The behavior of foams under compressive loading was studied, and the compressive strength was observed to exhibit a decrease from 5.24 to 1.13 MPa with increase in ESO content. The nature of collapse plateau however suggested an increase in the fraction of load supported by the fluid in this region. This juxtaposed with a decrease in foam density deviated from Rehkopf's evaluation of load distribution between polymer and fluid. The foams were shown to exhibit high thermal stability, which increased from 182 to 208 °C with the amount of ESO present in the matrix.

In this paper, we set to examine the inter-laminar shear strength of a fiber-reinforced composite part manufactured via a stepped-concurrent ultraviolet curing and layering process. This process was specifically proposed for making epoxy-based thick parts, whereby a layer-by-layer, model-based, optimal layering time and ultraviolet control scheme is set up with the objective of minimizing the degree of cure deviation across the final thick part. We focus on a cationic curing process wherein additional energy savings are possible by switching off the ultraviolet source after initiating the curing reaction with the ultraviolet source at each layer addition. Since the inter-laminar sheer strength of parts made via a layering process is often a concern, we consider the application of in-situ consolidation pressure in the layering process. We then characterize the inter-laminar shear strength by manufacturing samples with application of different in-situ consolidation pressures and measuring the inter-laminar shear strength of each sample by the short-beam shear test. The results showed that the inter-laminar shear strength of composite parts fabricated with the proposed stepped-concurrent curing, and layering process increases with the applied consolidation pressure up to a point. Scanning electron microscopy of samples cured at different in-situ consolidation pressure showed that the sample with optimum consolidation pressure has relatively uniform fiber to resin distribution and hence improved inter-laminar shear strength.

Epoxidation of high-linolenic perilla oil was carried out in the presence of solid acidic ion-exchange resin at varying reaction temperatures for 8 h. A pseudo two-phase kinetic model that captures the differences in reactivity of double bonds at various positions in the fatty acid of a triglyceride molecule during both epoxy formation and cleavage was developed. The proposed model is based on the Langmuir-Hinshelwood-Hougen-Watson (L-H-H-W) postulates and considers the adsorption of formic acid on the catalyst as the rate-determining step. To estimate the kinetic rate constants of various reactions, genetic algorithm was used to fit experimentally obtained iodine and epoxy values of epoxidized perilla oil. A re-parametrized form of Arrhenius equation was used in the proposed model to facilitate the precise estimation of parameters with least computational effort. The obtainment of the least error between experimentally determined and theoretically predicted iodine and epoxy values indicates the robustness of the proposed model.

The authors detail the creation of a hybrid multi-material structure via the injection of polypropylene (PP) with high ductility into a robust CF/Epoxy thermoset sheet. The purpose of this hybrid method involves combining the inherent properties of both thermoset and thermoplastic materials in a new hybrid structure while reducing the cycle time and tooling system. Specifically, the effect of pre-heating time, injection temperature, and injection speed rate on the deformation of the prepreg and polymer penetration through prepreg sheets were evaluated. The results of the experimental design indicated that the hybrid structures were manufactured with no penetration present in any combinations of parameters. An inadequate deformation characterized the samples created at a lower injection temperature, and pre-heating time, with insufficient adhesion as a result. High injection speed resulted in enhancing the formability and joinability. Also, the effect of the mentioned process parameters on the curing of prepreg sheet and bending behavior of final hybrid component were investigated through Differential Scanning Calorimetry (DSC), and the Three-point flexural test, respectively. Both DSC and Three-point test results illustrated the increase in pre-heating time, and the injection temperature enhanced the amount of curing and an increase of stiffness on the hybrid component.

Reactive extrusion was used for dicumyl peroxide (DCP)-initiated grafting of glycidyl methacrylate (GMA) to poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). The effects of GMA and DCP content and their weight ratio on the GMA grafting percentage (GP%), the polymer melt viscosity, and the PHBV molecular weight were investigated. FTIR spectroscopy determined that the DCP did indeed initiate GMA grafting. However, the changes in both the zero-shear viscosity (η0) and the molecular weight suggested the existence of crosslinking products in the extruded polymers. A negative correlation between the degree of crystallinity (χc) of the PHBV-g-GMA and the GP% suggested the influence of chain branching on crystallinity. In addition, the GMA content was found as a key factor determining the GP%. The PHBV-g-GMA was used as a matrix polymer in cellulose nanocomposites to evaluate its effects on CNC dispersion and CNC-matrix adhesion relative to the unmodified PHBV matrix. The SEM images and the change in crystallization temperature suggested enhanced dispersion of CNC in a PHBV-g-GMA matrix. However, little increase in strength properties were found with CNC addition suggesting inadequate stress transfer between the matrix and CNCs.

CF/Epoxy sheet with injected thermoplastic is a hybrid structure that combines high mechanical properties of thermoset composite with the toughness and complex geometries of injected thermoplastic into a single component. To overcome the high cycle time and production cost associated with the manufacturing of such hybrids, the authors undertook a feasibility study for developing an integrated technology for the manufacturing of thermoset CF/Epoxy prepreg sheet and injected thermoplastic polypropylene. First, several demonstrator parts were manufactured to elucidate the effect of the process parameters on the process performance and the appearance of the final hybrid component. Then, to have a better understanding about the curing condition of prepreg sheet during this hybrid process, a set of numerical simulation was conducted to study the relationship between the initial preset machine parameters (i.e., holding time, injection speed rate,) on the temperature distribution and history of the prepreg sheet. The results show that the proposed technology is capable of manufacturing hybrid components in a single operation under different process and design conditions.

In this study, cellulose nanocrystals (CNCs) with PEG grafts of various lengths (1 k, 2 k, 5 k, and 10 kDa) were prepared via a polydopamine (PDA) mediated method in the aqueous solution. The prepared CNC-PEGs were further used to reinforce the polyvinyl alcohol (PVA) at the loading of 0, 1, 3, 5, and 7 wt% in order to demonstrate the effects of the PEG length on the properties of the PVA/CNC nanocomposites. PEG surface modification resulted in simultaneous improvements in stiffness and toughness. The graft lengths have noticeable impacts on the properties of composites. The shorter graft yields better enhancement in strength and stiffness, attributable to the high efficiency in the stress transfer and high interface adhesion. The longer PEG graft length yields high graft-matrix entanglement, forming a thicker rubbery coating layer that enhances the toughness of PVA/CNC composites.

Fullerene-based low-dimensional (LD) heterostructures have emerged as excellent energy conversion materials. We constructed van der Waals 1T-MoS

Every day-increasing connectivity and access to data can provide valuable insight to the plastics industry. While the amount of accessible data has been increasing, the means to process and store it efficiently while squeezing valuable process information out of it has not been prioritized. The increase in connectivity has led to much of this data being stored and used in cloud computing systems which can be both monetarily and computationally expensive. Motivated by this fact, the feasibility of using real-time data directly captured from injection molding machine is investigated in terms of their capabilities for online quality monitoring. Using the built-in sensors that are usually existed in the standard injection molding machines (barrel pressure, screw position, and clamp force) and a dimensional reduction method, models are derived to predict quality of injection molded parts (Weight, Thickness, and Diameter). The developed models show high predictive capability with R2 values ranging from 0.89–0.97. Moreover, the combination of the proposed feature extraction method and implementation of Partial Least Squares Regression (PLS) demonstrates that most of the computing for automatic quality control can be done on local edge computing hardware with a significantly summarized data, and only control commands need to be sent through the cloud.