Production of polyamide 11 microparticles for Additive Manufacturing by liquid-liquid phase separation and precipitation
Production of polyamide 11 microparticles for Additive Manufacturing by liquid-liquid phase separation and precipitation
复制标题
DOI：
10.1016/j.ces.2018.11.051
复制
发表时间：
2019-04-06
影响因子：
4.7
通讯作者：
Schmidt, Jochen
中科院分区：
文献类型：
--
作者：
Dechet, Maximilian A.;Goblirsch, Anja;Schmidt, Jochen
在此贡献中，研究了液-液相分离（LLPS）和乙醇沉淀作为生产用于选择性激光烧结（SLS）的聚酰胺11（PA 11）粉末的方法。为此，通过浊度测量实验确定PAII-乙醇体系的浊点和溶液温度曲线。推导出颗粒形成的适宜体系组成和温度范围。在LLPS和沉淀过程中颗粒特性对工艺参数（聚合物浓度，搅拌条件和温度制度）的依赖性进行了评估，并对产品的尺寸和形态进行了表征。此外，结构，流变和热特性进行了分析，并与工艺参数。测定分子量分布。在去除细料和用疏水气相二氧化硅干燥涂覆后，获得了平均粒径为91 μ m的优化的PA 11粉末，其显示出良好的SLS流动性。这种优化的PA 11粉末的SLS加工性通过在激光烧结机中构建多层测试样品来证明。有了这一贡献，我们提出了一个全面的工作流程，通过沉淀制造的SLS粉末的工艺开发，产品表征和产品应用。(C)2018爱思唯尔有限公司版权所有。
Within this contribution liquid-liquid phase separation (LLPS) and precipitation from ethanol was studied as an approach to produce polyamide 11 (PA11) powders for selective laser sintering (SLS). To this end, the cloud point and solution temperature curve of the PAll-ethanol system was determined experimentally via turbidity measurements. The proper range of system composition and temperature for particle formation was deduced. The dependence of particle characteristics on process parameters (polymer concentration, stirring conditions and temperature regime) during LLPS and precipitation was assessed and the products were characterized with respect to their size and morphology. Furthermore, structural, rheological and thermal characteristics were analyzed and correlated with process parameters. Molecular weight distributions were determined. After removal of fines and dry coating with hydrophobic fumed silica, an optimized PA11 powder with mean particle size of 91 mu m showing good flowability for SLS was obtained. SLS processability of this optimized PA11 powder was demonstrated by building multilayered test specimens in a laser sintering machine. With this contribution, we present a comprehensive workflow for the process development, product characterization and product application of a SLS powder manufactured via precipitation. (C) 2018 Elsevier Ltd. All rights reserved.