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In an effort to move towards a more sustainable future, bioplastics are being promoted as sustainable alternatives to plastics. Nevertheless, the market transition to bioplastics requires the materials to be incorporated into already existing manufacturing processes with the capability of creating a variety of three-dimensional customized shapes. Thermoforming is a widely used process in the plastics industry to manufacture a wide range of products of different sizes. However, thermoforming of several types of bioplastics has received relatively scant research to date. Therefore, this study examines the feasibility of thermoforming three bioplastics, Polylactic Acid (PLA), Cellulose Acetate Propionate (CAP), and Bio-Polyethylene Terephthalate (Bio PET). Materials were tested using an industrial Form-Fill-Seal (FFS) thermoforming line equipped with a custom-designed sheet-forming chamber. Additionally, the results were compared to a commonly used thermoforming plastic, multilayer polyethylene/polyethylene terephthalate. The aim is to provide insight into the possibilities of this transition from a perspective of energy efficiency, processing speed, and possible shape-making, with an assessment of the optimal forming window for materials and a detailed analysis of the formed products. A further investigation is conducted into factors that may hamper the thermoforming performance of the materials being investigated. Results indicate that the thermoforming performance and processability of the studied materials differ clearly; PLA and BioPET yet face limitations in processability considering their properties and possibilities for their incorporation into existing thermoforming lines, whereas CAP material can compete the commercial materials on the basis of product shape, production speed, and energy requirements in thermoforming. [ABSTRACT FROM AUTHOR]

Plastics that are renewable and biodegradable have become increasingly popular in the quest for greener and more sustainable food packages. These so-called bioplastics are designed to replace traditional petrochemical polymers with renewable natural resources. To be a viable alternative to these oil-based resources the material must be successfully integrated into existing mass-manufacturing processes that transform material sheets into three-dimensional products. The purpose of this study was to examine the effect of process parameters, particularly moulding temperatures, on the 3D-formability of bioplastics during thermoforming. A numerical/visual comparison was conducted between thermoformed tray packages and reference packages made of petrochemical polymers focusing primarily on product geometry and stiffness. Three bioplastic materials were selected based on their availability and suitability for the process: Polylactic Acid (PLA) and Cellulose Acetate Propionate (CAP). The sample materials were formed to specimen trays using a custom-designed sheet-forming chamber on a commercial Form-Fill-Seal (FFS) thermoforming line. Material changes necessitated separate optimizations of the process parameters for each material. It was found that the material properties of bioplastics set certain limits to the formed geometric shapes, but these limits can be addressed during the packaging design phase, making bioplastics a viable material for environmentally friendly yet economically feasible packages. [ABSTRACT FROM AUTHOR]