Haoting Yin,Dongyuan Ye,Tianyu Wu,Xiaoyu Meng,Hai-Mu Ye
The sluggish crystallization kinetics of poly(ethylene succinate) (PES), a biodegradable aliphatic polyester with promising mechanical properties, severely restricts its industrial processing and application. To address this limitation, this study introduces two bio-derived hexahydric alcohols, myo -inositol (MIS) and dipentaerythritol (DPE), as nucleating agents to regulate PES crystallization. Non-isothermal and isothermal differential scanning calorimetry, polarized optical microscopy, and wide angle X-ray diffraction analyses reveal that both MIS and DPE significantly enhance nucleation density and crystallization rates via epitaxial templating and hydrogen-bonding interactions. DPE outperforms MIS, achieving 19.1 °C increase in crystallization temperature and 28% improvement in relative crystallinity at 2 wt% loading, attributed to its superior epitaxial surface provision and stronger intermolecular interactions for PES chains. Fourier transform infrared spectroscopy further confirms the plasticizing effect of these agents, which reduces rigid amorphous fractions and enhances chain mobility. The synergistic mechanism combines heterogeneous epitaxial nucleation and chain lubrication, enabling accelerated crystallization kinetics without compromising biodegradability. This work provides a sustainable strategy to optimize PES processing efficiency and performance, advancing its potential as a viable alternative to conventional thermoplastics.
A series of Ni catalysts were prepared with various supports (ZSM-5, Al 2 O 3 , SiO 2 , bentonite, TiO 2 , and kieselguhr) and their catalytic properties were investigated for the hydrogenation of cellobiose and glucose, the reaction intermediates of cellulose hydrolysis in hot-compressed water, in order to elucidate the key factors to control the hexitols selectivity in the hydrolytic hydrogenation of cellulose. For the hydrogenation of cellobiose, hexitols were produced with a selectivity above 82% over Ni/ZSM-5, but the other checked Ni catalysts produced large amount of glycerol, ethylene glycol , and propanediol, and the product distribution strikingly depended on the catalysts used. On the basis of kinetic experiments, it was the hydrogenation/dehydrogenation ability of Ni catalyst that played a critical role in controlling hexitols selectivity. High hydrogenation and inferior dehydrogenation activity of Ni catalysts were essential for obtaining high yield of hexitols in the hydrolytic hydrogenation of cellulose. The synergistic effect of Ni active species and acid–base sites was proposed to accelerate the dehydrogenation of sorbitol and thus reducing the yield of hexitols.
危险品化学品经营许可证（带存储）