Recycling of Medical PVC Waste from Used Peritoneal Dialysis Solution Bags to Soundproofing Sheets

This study explores the recycling of used peritoneal dialysis (PD) solution bags, composed primarily of poly(vinyl chloride) (PVC), into soundproofing sheets as a sustainable strategy for managing medical plastic waste. The fabrication process involved mixing all components in an internal mixer, followed by sheet formation using a two-roll mill and hot compression molding. By varying the contents of dioctyl phthalate (DOP) as a plasticizer (15-30 phr) and barium sulfate (BaSO4) as a filler (30-70 phr), the properties of the PVC sheets including physical, mechanical, flame resistant and soundproofing properties were investigated. The results indicated that the appropriate DOP contents for fabricating the 1 mm-thick PVC sheets were 25 and 30 phr, which gave dense, light yellow PVC sheets with good flexibility for all ratios of BaSO4. In contrast to the hardness, the tensile strength decreased when increasing the DOP and BaSO4 contents. The soundproofing testing showed that the increases in both the DOP and BaSO4 contents resulted in the decrease in the noise reduction coefficient (NRC), and consequently the increase in the sound reflecting ability. The best formulation to produce the 1 mm-thick soundproofing sheets was 30 phr DOP and 50 phr BaSO4, giving a sound reflection ability of 97%. The UL94 vertical flammability test revealed that the developed soundproofing sheets were classified into a V-2 class.