Transparency Research of Poly(L-lactide) Films and Its Modified Films

摘要

Using polyhedral oligomeric silsesquioxanes (POSS) to modify Poly (L-lactide) (PLLA) had been studied to improve the properties in recent years. In the paper, the transparency of PLLA films and modified PLLA films was studied. First, PLLA films and a series of modified PLLA films were prepared. Star-shaped POSS-g-PLLA was prepared by using L-lactic acid and POSS-NH3CI in the presence of stannous (II) octanoate (Sn (Otc)_2) catalyst. A series of modified films were prepared by using octa(γ-chloroammoniumpropyl) octasilsesquioxane (POSS-NH_3Cl) and POSS-g-PLLA. Meanwhile, the reaction was characterized by Fourier Transform Infrared spectrometry (FTIR). Secondly, transparency of PLLA films, PLLA/POSS-NH_3CI films, PLLA/POSS-g-PLLA films and POSS-g-PLLA films were investigated, respectively. The conclusions were as follows: (1) the transparency of PLLA/POSS-NH_3CI, PLLA/POSS-g-PLLA and POSS-g-PLLA films was improved. (2) The transparency of POSS-g-PLLA films was the best, and the transparency of PLLA/POSS-g-PLLA films was better than that of PLLA/POSS-NH_3Cl films. (3) The transparency of POSS-g-PLLA films was significantly improved. In the visible spectral range (400-800 nm), the transparency of POSS-g-PLLA films was increased with the increase of POSS-NH3CI. and the transparency of the films improves even 58% in some wavelength. These phenomena were explained theoretically.