Functional dyeable polypropylene fabric development and process parameter optimization Part I: Dyeable modified polypropylene development with process parameter optimization

This study aims to develop dyeable modified polypropylene (PP) granules with disperse dye. The optimal dyeable modified PP granule process used polyester as a mixed copolymer. The purpose was to overcome the excessive difference between the polyester material melting point and PP melting point. The development of a low-melting modified co-polybutylene adipate terephthalate (Co-PBAT) was the key point. After the low-melting modified Co-PBAT was presented, PP and a PP grafting maleic anhydride compatibilizer were made into a composite by dual-screw mixing process. The disperse dye dyeability was reached by the molecular behavior of the Co-PBAT chain segment. The prepared material was applied to explore the thermal properties of modified ester pellets and the functional group was verified by Fourier infrared spectroscopy. In this study, the Taguchi method and principal component analysis were used to optimize the process parameter design of two quality characteristics; namely, the color strength and the polymer melt flow index (MFI). According to the results, the multi-quality optimization of the ester pellets consisted of a modified Co-PBAT melting point of 170°C, the modified Co-PBAT content of 9 wt%, the compatibilizer content of 3 wt%, and the mixing temperature of 205°C. The MFI of the regular PP polymer was 28.1 g/10 min, the color strength was 100 K/S. For the optimal process, the MFI of the PP/Co-PBAT dyeable granules was 37.88 g/10 min, and the color strength was 121.31 K/S. It could be observed that the developed polymer had good circulating workability and color strength.