清华化工论坛第五十五讲将于6月29日10:00在英士楼201会议室举行,欢迎各位老师参加🧝♀️!
报告题目🧜🏿♂️:Dissolving the Insoluble
报告人🦖: Paschalis Alexandridis
UB Distinguished Professor
Department of Chemical and Biological Engineering
University at Buffalo (UB), The State University of New York (SUNY)
报告时间:6月29日周五10:00
报告地点:英士楼201
摘要:
The recalcitrance to dissolution hinders the processing of crystalline polymers. [Curr. Opin. Green Sustainable Chem. 2018, 14, 40-52. DOI: 10.1016/j.cogsc.2018.05.008] A phenomenological model is presented that captures the phenomena governing the dissolution of semicrystalline polymers, e.g., solvent diffusion, transformation from crystalline to amorphous domains, specimen swelling, and polymer chain untangling. The model is validated for the case of cellulose (cotton) fiber swelling and dissolution in various solvents. [Cellulose 2017, 24 (2), 571-590. DOI: 10.1007/s10570-016-1145-1] A parametric sensitivity analysis is carried out to assess the impact of various parameters on the dissolution of cellulose fibers. [AIChE Journal 2017, 63 (4), 1368-1383. DOI: 10.1002/aic.15615] [Biomacromolecules 2018, 19 (2), 640-651. DOI: 10.1021/acs.biomac.7b01745] To emulate large-scale processing of cellulosic biomass where the particles exhibit a distribution of size and degree of crystallinity, a model is developed in which the behavior of a population of particles is obtained from an ensemble of individual polymer particle dissolution models. [Chem. Eng. J. 2018, 350, 37-48. DOI: 10.1016/j.cej.2018.05.167] Using this population ensemble model, various particle size distributions are analyzed for different dissolution parameters. The insights obtained from these studies would be useful for the rational design and optimization of solvent systems and processes for the dissolution of semicrystalline polymers such as cellulose, polyglycolic acid, and polyesters. [Bioresource Technol. 2017, 228, 330-338. DOI: 10.1016/j.biortech.2016.12.049]