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While thermoplastic polymers exhibit several desirable properties, their applicability is limited by their high viscosity and extreme processing conditions. To overcome these limitations, in this study, we used the thermoforming process to produce carbon fiber/polyetherketoneketone (CF/PEKK) laminates, which were pre-made through an oven-based consolidation process using prepregs. The laminates were produced at three different heating rates ($40^{\circ }$C/min, $75^{\circ }$C/min and $100^{\circ }$C/min). The laminates produced at the heating rate of $40^{\circ }$C/min showed improved interlaminar shear strength, $90^{\circ }$ tensile strength, and average interlaminar fracture toughness. On the other hand, heating at rates higher than $40^{\circ }$C/min increased the initiation value of the interlaminar fracture toughness ($G_{\mathrm{\text{IC}}-\mathrm{\text{I}}})$ but resulted in nonuniform composites of poor quality. This is because increasing the heating rate reduced the uniformity of the heat distribution with the laminates, resulting in the polymer molecules exhibiting different binding rates and thus nonuniform cross-linking. Thus, the proposed method is a suitable one for producing high-quality thermoplastic composites.

The chemical bonding of substrate and adhesive occurs in thermoplastic adhesive bonding, and the molecular deformation caused by the difference in chemical bonding affects the adhesive properties. Therefore, it is essential to investigate the correlation between the molecular deformation of interphase and the strength change behavior. As adhesive bonding involves the combination of two materials with different coefficients of thermal expansion, it is important to analyze the behavior at high temperatures. Therefore, to determine the effects of the molecular deformation of the interphase caused by differences in the adhesive type on the high-temperature performance when adhesive bonding is applied to thermoplastic composites, fusion and adhesive bonding were applied to carbon fiber/polyetherketoneketone thermoplastic composites. The lap shear strength test was conducted at three different temperatures to evaluate the adhesive performances. Scanning electron microscopy was used to determine the fracture mode and the molecular deformation of the interphase was analyzed by Fourier transform infrared spectroscopy. Temperature does not affect the strength of fusion bonded composites. When polyetheretherketone is used as an adhesive, the strength decreases as the temperature increases. When polyetherimide is used as an adhesive, the strength first increases at $100^{\circ }$C and then decreases at $160^{\circ }$C. The amount of C–O–C and C=C bond formation, diphenyl ketone group, and imide carbonyl group in the interphase followed the same trend as the strength.

Poly(butyl acrylate-co-methyl methacrylate)/clay nanocomposites were synthesized via emulsion polymerization with an emulsifier (sodium dodecyl benzene sulfonate, SDBS), an initiator (ammonium persulate, APS), acrylic acid ester monomer and Na-montmorillonite. It was found that the addition of SDBS and water widened the gap between clay layers and facilitated monomers to penetrate into clay. Through initiator, comonomers were polymerized in the montmorillonite galleries. The structure of extracted nanocomposites was confirmed by XRD, transmission electron microscopy (TEM). Their thermal property and molecule weight were investigated by differential scanning calorimetry (DSC) and gel-penetrate chromatogram (GPC).

Microfluidics is a multidisciplinary technology which enables the face-lift crossing a wide range of applications such as life science research, point-of-care diagnostics and personal medicine. Polymer materials, especially thermoplastics, are dominating this emerging market due to the low material cost and the ease of mass production. This paper reviews the major fabrication technologies for making polymer, especially thermoplastic microfluidic chips, such as micro tooling, injection molding, bonding and surface treatment. The paper also summarizes the key challenges in fulfilling the needs of next generation microfluidic products.

In the area of tissue engineering, single screw extrusion (SSE) has gained attention due to its versatility and efficiency in fabricating polymer-based scaffolds. Furthermore, advancements such as the implementation of extrusion techniques and the integration of bioactive agents have significantly expanded the capabilities of SSE. This study aims to investigate the configuration of a custom-designed plastic extrusion for tissue engineering, highlighting its potential in fabricating suture technology for various regenerative biomedical applications. Furthermore, the challenges and future perspectives in SSE technology are discussed, with a focus on the need for additional research to optimize processing parameters, enhance structure bioactivity, and facilitate clinical usage. SSE provides precise regulation of structure morphology, mechanical properties, and porosity, which are critical factors that influence cell behavior and tissue regeneration. Overall, SSE holds great promise as a scalable and cost-effective manufacturing technique for producing polymer-based structures with tailored properties, advancing the field of tissue engineering towards effective clinical solutions. The paper provides a comprehensive overview of a filament extruder production machine that is capable of manufacturing high-quality filament sutures (FS) using thermoplastic materials, specifically bio-protein derived from human serum albumin. The main focus of the paper is to explain the design and operation principles of the filament extruder. The extruder is equipped with a die that can measure a range starting from 2.5 mm and going down to smaller scales. This allows for the extrusion of filaments with a diameter as small as 1.75 mm. Although the design of the extrusion apparatus closely resembles that of commercially available machines, the focus here is on its adaptability and cost-effectiveness for laboratory-scale production. Overall, the research contributes to advancing the understanding of extrusion processing technologies in the context of biomedical applications, with a specific focus on utilizing human serum albumin-derived thermoplastics for manufacturing FS.