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This book covers a wide range of applications and uses of simulation and modeling techniques in polymer injection molding, filling a noticeable gap in the literature of design, manufacturing, and the use of plastics injection molding. The authors help readers solve problems in the advanced control, simulation, monitoring, and optimization of injection molding processes. The book provides a tool for researchers and engineers to calculate the mold filling, optimization of processing control, and quality estimation before prototype molding.

In this study, machine learning algorithms (MLA) were employed to predict and classify the tensile strength of polymeric films of different compositions as a function of processing conditions. Two film production techniques were investigated, namely compression molding and extrusion-blow molding. Multi-factor experiments were designed with corresponding parameters. A tensile test was conducted on samples and the tensile strength was recorded. Predictive and classification models from nine MLA were developed. Performance analysis demonstrated the superior predictive ability of the support vector machine (SVM) algorithm, in which a coefficient of determination and mean absolute percentage error of 96% and 4%, respectively were obtained for the extrusion-blow molded films. The classification performance of the MLA was also evaluated, with several algorithms exhibiting excellent performance.

Objectives This study aimed to compare the 3D changes of maxillary arches in infants with bilateral cleft lip and palate (BCLP) undergoing vacuum formed nasoalveolar molding appliance with active screw (VF-NAM) to those who received conventional Grayson (G-NAM). Methods A total of 24 BCLP infants were randomly allocated into, group 1 ( n  = 12) who received V-NAM and Group 2 ( n  = 12) underwent G-NAM appliances. In the V-NAM group, all infants received 1- 2 vacuum formed maxillary plates incorporated with active retraction screw. In the G-NAM group, Grayson’s NAM technique was followed. The nasal stents were added to the maxillary plates in both groups in the same manner to mold the deformed nasal cartilages. Sixteen items in the digital maxillary models were analyzed at T1 (pre-NAM therapy) and T2 (post-NAM therapy) using 3D software. Parametric data were analyzed using a repeated measures ANOVA test to compare between groups and assess changes within each group by time, while non-parametric data were analyzed using the Mann–Whitney U test to compare between groups and the Wilcoxon signed-rank test to assess changes within each group by time. Results By the end of this study, both groups showed no statistically significant differences in all variables associated with changes in the transverse and vertical arch dimensions except the mid-arch width in which the VF-NAM group exhibited a significantly greater change compared to the G-NAM group, with an effect size of 0.953 (CI 95%: -0.03 − 2.46). In the sagittal dimensions, A more significant decrease in the right and left alveolar cleft widths was observed in the VF-NAM group relative to the G-NAM group with effect sizes of 0.89 (CI 95%: -3.73–0.11). and 0.85 (CI 95%: -3.82 − 0.14), respectively ( P  < 0.05). Conversely, the G-NAM group demonstrated a significantly greater increase in the premaxillary rotation angle compared to the VF-NAM group, with an effect size of 0.875(CI 95%: -3.06 − 13.56) ( P  < 0.05). Conclusion Both VF-NAM and G-NAM effectively reduced alveolar cleft gaps, retracted the premaxillary segment, and normalized alveolar contour. However, VF-NAM resulted in greater reductions in cleft width and mid-arch width expansion. Conversely, G-NAM was more effective in improving premaxillary rotation. These findings may contribute to clinical decision-making in the early cleft management by guiding the selection of appliances based on individual anatomical characteristics. The use of a VF-NAM or G-NAM appliance could strategically optimize pre-surgical outcomes and enhance treatment planning in infants with BCLP. Trial registration NCT04966572 -July 8th 2021.

The quality control of plastic products is an essential aspect of the plastic injection molding (PIM) process. However, the warpage and shrinkage deformations continue to exist because the PIM process is easily interfered with by several related or independent process parameters. Thus, great efforts have been devoted to optimizing process parameters to minimize the warpage and shrinkage deformations of products during the last decades. In this review, we begin by introducing the manufacturing process in PIM and the cause of warpage and shrinkage deformations, followed by the mechanism about how process parameters, like mold temperature, melt temperature, injection rate, injection pressure, holding pressure, holding and cooling duration, affect those defects. Then, we summarize the recent progress of the design of experiments and four advanced methods (artificial neural networks, genetic algorithm, response surface methodology, and Kriging model) on optimizing process parameters to minimize the warpage and shrinkage deformations. In the end, future perspectives of quality control in injection molding machines are discussed.

Most lenses on the market can be made by injection molding. However, defects such as weld lines and residual stress are often generated during the production of concave products. Compression molding eliminates these problems, and the cost of the required molding machinery is relatively low compared to other processes. The process can also be highly automated, which is essential for plastic manufacturing. This study proposes an innovative mold for compression molding for a double-concave lens. There is no requirement for angular alignment because the lens is axisymmetric. A compact compression mold without leader pins is created. Parameter optimization for the powder and granular PMMA is optimized using the Taguchi method. The significant compression molding parameters are the pre-pressing period, the pressing temperature, the pressing force, and the pressing period. The surface profiles of finished products are measured, and a factor response analysis is used to determine the effect of various parameters on the finished product. The pressing force was shown to be the most significant factor for powder. However, granules need a long enough pre-pressing time because the gap widens. A confirmation experiment was conducted with the optimized parameters. The profile of the compressed double-concave lens is measured and compared with the mold insert. Powder PMMA is more suitable for compression molding than granular PMMA. However, regardless of the material type, the compression-molded double-concave lens is 96% replicable or more.

Tremendously negative effects have been generated in recent decades by the continuously increasing production of conventional plastics and the inadequate management of their waste products. This demands the production of materials within a circular economy, easy to recycle and to biodegrade, minimizing the environmental impact and increasing cost competitiveness. Bioplastics represent a sustainable alternative in this scenario. However, the replacement of plastics must be addressed considering several aspects along their lifecycle, from bioplastic processing to the final application of the product. In this review, the effects of using different additives, biomass sources, and processing techniques on the mechanical and thermal behavior, as well as on the biodegradability, of bioplastics is discussed. The importance of using bioplasticizers is highlighted, besides studying the role of surfactants, compatibilizers, cross-linkers, coupling agents, and chain extenders. Cellulose, lignin, starch, chitosan, and composites are analyzed as part of the non-synthetic bioplastics considered. Throughout the study, the emphasis is on the use of well-established manufacturing processes, such as extrusion, injection, compression, or blow molding, since these are the ones that satisfy the quality, productivity, and cost requirements for large-scale industrial production. Particular attention is also given to fused deposition modeling, since this additive manufacturing technique is nowadays not only used for making prototypes, but it is being integrated into the development of parts for a wide variety of biomedical and industrial applications. Finally, recyclability and the commercial requirements for bioplastics are discussed, and some future perspectives and challenges for the development of bio-based plastics are discussed, with the conclusion that technological innovations, economic incentives, and policy changes could be coupled with individually driven solutions to mitigate the negative environmental impacts associated with conventional plastics.

High-performance discontinuous carbon-fiber-reinforced thermoplastics (CFRTPs) offer promising manufacturing flexibility and recyclability for advanced composite applications. However, their mechanical performance and reliability strongly depend on the internal fiber architecture, which is largely determined by the molding process. In this study, three distinct compression molding approaches—CFRTP sheet molding compounds (SMCs), bulk molding compounds (BMCs), and free-edge molding compounds (FMCs)—were systematically evaluated to investigate how processing parameters affect fiber orientation, tape deformation, and impregnation quality. X-ray micro-computed tomography (XCT) was employed to visualize and quantify the internal structures of each material, focusing on the visualization and quantification of in-plane and out-of-plane fiber alignment and other internal structure features. The results indicate that CFRTP-SMC retains largely intact tape layers and achieves better impregnation, leading to more uniform and predictable internal geometry. Although CFRTP-BMC exhibits greater tape deformation and splitting due to increased flow, its simpler molding process and better tolerance for tape shape distortion suggest potential advantages for recycled applications. In contrast, CFRTP-FMC shows significant tape fragmentation and poor impregnation, particularly near free edges. These findings underscore the critical role of a controlled molding process in achieving a consistent internal structure for these materials for the first time. This study highlights the utility of advanced XCT methods for optimizing process design and advancing the use of high-performance discontinuous CFRTP in industry.

Edible films and coatings are thin layers, with a thickness of generally less than 0.3 mm, that are used for centuries to protect food products and to avoid the deterioration of their ingredients. While an edible coating is formed directly on the food surface by spraying, dipping or spreading techniques, an edible film is first produced by solvent casting, compression moulding or extrusion procedures and posteriorly implemented into the food products, being placed on or between food components. The food sector is the main consumer of packaging materials, with the edible films and coatings being mainly applied into meat and seafood, fruits and vegetables and dairy products. These packaging materials, normally formed by a cohesive structured biopolymer, additives and/or a solvent, can also be used as carriers of several active ingredients, like colourants, flavours, nutrients and antimicrobial and antioxidant compounds, which can prolong the shelf life, improve the organoleptic characteristics and enhance the nutritional value of the final product. Nowadays, due to health and environmental concerns, the use of natural antioxidant and antimicrobial sources, like natural extracts, is emerging in the packaging research sector, being widely applied as active ingredients in edible film and coating formulations. A wide range of studies revealed the comprehensive interests in edible films and coatings with functional properties. So, the main objective of this review is to cover the recent works on edible films and coatings, including the investigation of recent advances in the incorporation of active compounds, namely natural extracts, and the challenges and opportunities for future research.

Natural fiber‐reinforced composites have emerged as a promising alternative in various industries, including automotive, aerospace, construction, and civil engineering, owing to their eco‐friendly nature and favorable mechanical properties. However, challenges such as low thermal stability and high moisture absorption limit their widespread use. To overcome these limitations, surface modifications such as mercerization, benzoylation, silane treatment, and acetylation have been extensively explored. Hybrid composites (HCs), combining natural and synthetic fibers, offer a compelling solution by harnessing the unique properties of both materials. This review comprehensively examines the types of fibers and polymers utilized in HCs, along with various chemical treatments to enhance their properties. Additionally, a detailed analysis of different manufacturing processes for HCs is provided, including hand lay‐up, vacuum‐assisted resin transfer molding, autoclave molding, injection molding, and compression molding. Furthermore, this review highlights recent advancements in HCs and their applications. Significant outcomes include a deeper understanding of the synergistic effects between natural and synthetic fibers, improved mechanical and thermal properties, and enhanced applications in diverse industries. The potential of HCs as a sustainable and high‐performance material solution emphasizes the importance of ongoing research and innovation in this field to overcome existing challenges and unlock new possibilities for composite engineering. Highlights Surface modifications such as mercerization, benzoylation, and silane treatment enhance the properties of natural fibers in composite materials. Hybrid composites (HCs) offer unique advantages by combining natural and synthetic fibers, including improved thermal, mechanical, and damping properties. Various chemical treatments and manufacturing processes contribute to enhancing the properties and applications of HCs. Recent advancements in HCs have led to an improved understanding and utilization of composite engineering across multiple industries. The review discusses challenges, opportunities, and future prospects for HCs, emphasizing the need for ongoing research and innovation in this field. Natural fiber‐reinforced hybrid composites are emerging as eco‐friendly alternatives in different industrial applications for their favorable mechanical and thermal properties.

Polylactide (PLA) is known as one of the most promising biopolymers as it is derived from renewable feedstock and can be biodegraded. During the last two decades, it moved more and more into the focus of scientific research and industrial use. It is even considered as a suitable replacement for standard petroleum-based polymers, such as polystyrene (PS), which can be found in a wide range of applications—amongst others in foams for packaging and insulation applications—but cause strong environmental issues. PLA has comparable mechanical properties to PS. However, the lack of melt strength is often referred to as a drawback for most foaming processes. One way to overcome this issue is the incorporation of chemical modifiers which can induce chain extension, branching, or cross-linking. As such, a wide variety of substances were studied in the literature. This work should give an overview of the most commonly used chemical modifiers and their effects on rheological, thermal, and foaming behavior. Therefore, this review article summarizes the research conducted on neat and chemically modified PLA foamed with the conventional foaming methods (i.e., batch foaming, foam extrusion, foam injection molding, and bead foaming).