Sythesis and Properties of Novel Biodegradable PLA/H12MDI(MDI)/DMPA/butanediol Water-borne Polyurethane Composites

• Main Authors: Li, Yi-jie, 李宜潔
• Other Authors: Cheng, Pao-swu
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/34575407757475769416

碩士 === 高雄師範大學 === 化學系 === 98 === The main object of this research is to develop novel biodegradable water-borne polyurethane composites. Firstly, lactic acid monomer was heated to 150 ℃ in a vacuum system without adding any solvent or catalyst for homopolymerization to form the PLA prepolymers. The PLA diol was synthesized by direct condensation between PLA prepolymers and large amount of ethylene glycol. PLA diol, diisocyanate monomer (H12MDI or MDI), DMPA and 1,4-butanediol monomer were used as organic matrixes, coupling agent and chain extender agent respectively. In order to prepare a biodegradable water-borne polyurethane composites as a heat resistant, high transmittance and biodegradable of optical thin film, we successfully use PLA diol to condensation polymerize with diisocyanate monomer and to synthesize the novel biodegradable water-borne polyurethane composites in a low costs. The optimum reaction time, polymer mean molecular weight and optimum amount of reaction components were identified by GPC, FT-IR and NMR spectrometers. The transmittance and heat resistance properties of these composites are measured by UV-Visible and TGA. Experimental results show that these composites have above 84.6% transmittance and the best Td value is 416.64 ℃. The hardness of these composites are 3~4H, and the glass transition temperature(Tg) is not detected in 60~200 ℃ with DSC spectrometer. The surface resistanes of these optical thin films are 2.11×108~8.71×109 Ω/cm2 which have the anti-electrostatic characters. These composites are continuously degradation with the papain hydrolysis at 25 ℃ for 28 days. The WPU composites are corroded and have 57.4% weight lost. According to the morphology structure which is estimated by SEM, the optic thin films are evenly distributed and have obvious surface texture change after enzyme degraded.