David Grewell^1,*, Gowrishankar Srinivasan¹, Eric Cochran²

Journal of Renewable Materials, Vol.2, No.3, pp. 157-165, 2014, DOI:10.7569/JRM.2014.634112

Abstract Presented in this study is a novel recycling strategy for poly(lactic acid) (PLA) in which the depolymerization is rapidly promoted by the base-catalyzed hydrol-/alcohol-ysis of the terminal ester bonds under mild conditions. Post-consumer PLA water bottles were cut into approximately 6 x 2 mm plastic chips and heated to 50–60o C in water, ethanol, or methanol as the depolymerization medium. A variety of carbonate salts and alkaline metal oxides were screened as potential catalysts. High-power ultrasound was also investigated as a means to accelerate the PLA decomposition. Both mass loss and HPLC analysis of the treated suspensions showed that the… More >

Zhi-Yu Yang, Yi-Ling Chou, Hao-Chun Yang, Chin-Wen Chen^*, Syang-Peng Rwei^*

Journal of Renewable Materials, Vol.9, No.5, pp. 867-880, 2021, DOI:10.32604/jrm.2021.014476

Abstract A series of thermoplastic polyester elastomer (TPEE) and thermoplastic poly(ester amide)s elastomer (TPEaE) copolymers were obtained by depolymerizing PET (polyethylene terephthalate) by which the waste PET can be efficiently recovered and recycled into value-added products from a practical and economical point of view. The structure of TPEE and TPEaE was identified using nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopy (FT-IR). Differential scanning calorimetry (DSC) data showed that the melting temperature (T_m) decreased with the amide content increased. The glass transition temperature (T_g) was increased as introducing the amide group, and the formation of amide-ester and amide-amide hydrogen bonds… More >

Lifen Li¹, Zhigang Wu¹, Xuedong Xi², Baoyu Liu³, Yan Cao³, Hailong Xu³, Yingcheng Hu^4,*

Journal of Renewable Materials, Vol.9, No.2, pp. 219-235, 2021, DOI:10.32604/jrm.2021.012099

Abstract Lignin is an abundant renewable macromolecular material in nature, and degradation of lignin to improve its hydroxyl content is the key to its efficient use. Alkali lignin (AL) was treated with Brønsted acidic deep eutectic solvent (DES) based on choline chloride and p-toluenesulfonic acid at mild reaction temperature, the structure of the lignin before and after degradation, as well as the composition of small molecules of lignin were analyzed in order to investigate the chemical structure changes of lignin with DES treatment, and the degradation mechanism of lignin in this acidic DES was elucidated in this work. FTIR and NMR… More >