Design of compostable materials for the manufacturing of flexible tampon applicators

The present study aims to develop a more sustainable solution to plastic single-use tampon applicators. Tampon applicators are currently made with carboard or PE. Cardboard applicators are generally compostable, however many women prefer plastic applicators for major comfort during application. Plastic tampon applicators are characterized by high flexibility to allow a comfortable application of the tampon and allow the tampon to easily slide through the flexible petals on the upper part of the applicator. The shift to compostable materials is hindered by poor processability, inadequate mechanical properties and high cost of commercially available compostable polymers. In this respect, the present work deals with the design and development of innovative compostable polyester-based blends with high flexibility. The blends are based on binary blends PLA/PBS, PBS/PBAT and PLA/PBAT which were tailored for injection molding of flexible, highly processable and low cost compostable tampon applicators. The effect of the ratios between primary and secondary polymeric phase on flexibility of the petals and processability during injection molding was studied. Moreover, the effect on processability of the addition of a mineral filler to decrease material costs was also evaluated. Twin-screw corotating extrusion of the compound, injection molding of the plastic material for the fabrication of the tampon applicators, and evaluation of the thermophysical and mechanical properties of the applicators are hereinafter discussed. The compostable binary blends are found to be suitable for injection molding of the tampon applicators, exhibiting adequate processability during injection molding, flexibility of the petals during ejection from the mold.