||In this study, thermoplastic polyurethane (TPU) was blended with Sebacic acid (SA) modified tapioca starch/glycerol (SATPS) to prepare a new composite material (SATPU). The mechanical properties, physical properties, and thermal properties of TPU after plasma treatment and Sebacic acid modified starch blends were observed through a tensil test, water absorption test, and thermogravimetric analysis, respectively. The correlation between the surface structure of sample and material properties, as well as the biodegradability of composts were observed through use of the scanning electronic microscope (SEM). This investigation was divided into two parts.
In section 1, SA (2g) modified tapioca starch and was prepared with different weights of TPU (0g, 50g, 100g, 150g) by a single-screw extruder. The single-screw extruder’s elevated processing temperatures can improve the initial modulus of the materials. The stress-strain test showed that elongation at the break of STTPU150 & SATPU150 increased from 300% to 520%. By adding more TPU, elongation at the break of SATPS & SATPU150 increased from 50% to 520%. The SEM morphology found that the interface became more fractured with increased proportion of TPU particles. The more TPU, the more water absorption decreases. However, the less biodegradeable the sample becomes. In TGA analysis, the thermal stability of SATPU blends is much better than STTPU blends throughout the relevant temperature range.
In section 2, in light of material costs we used 100g TPU particles in the plasma treatment. The SA modified starch / plasma treatment (20w, 40w, 60w/1min, 3min, 5min) TPU was compounded by single-screw extruder. Plasma treatment of 20w-1min TPU improved the surface between TPU/SATPS. Elongation at the break of 20w-1min increased from 240% to 320%. SEM morphology observed that the 20w-1min interface fractures were greatly improved. The optimal plasma parameter of the blend (Starch/glycerol/TPU, 250/75/100g) having outstanding mechanical properties is 20watt 1min.