Efficient Simulation of Melt Viscoelasticity of Architecturally Varied Polymer Mixtures

不同结构聚合物混合物熔体粘弹性的有效模拟

• 批准号: 1067707
• 负责人: John Dorgan
• 金额: $ 25万
• 依托单位: Colorado School of Mines
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-08-01 至 2014-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1067707&HistoricalAwards=false
• 关键词: Efficient; Simulation; Melt; Viscoelasticity; Architecturally

1067707DorganIn this project, non-equilibrium molecular scale simulations are used to advance the understanding of flow of plastic materials during manufacturing operations. The proposed new modeling technique allows profound insight into the flow properties of different types (linear vs. branched) polymers and their mixtures. Such an understanding has been long sought in order to address issues in materials design and polymer processing. Ultimately, such understanding will lead to the best combination of polymer types that achieve a desired technical objective. Improved understanding of polymer flow properties provides a means of designing optimized additives capable of delivering desired properties. For validation, results from the new simulation techniques will be held against existing experimental data for novel polymer architectures and then used to design polymer mixtures having desirable processing characteristics. The intellectual merit of the work lies in developing the computer codes and in generating rheological data for complex polymeric systems. The work builds on existing success in accurately and completely describing the melt rheological properties of linear architectures using these same simulation techniques. In addition to the effects of chain architecture, confinement effects on flow are studied. The results generated can shed insight into novel confinement effects that are being exploited in emerging areas of nanotechnology. The activities pursued integrate research and teaching while promoting discovery; to successfully complete the project several subjects must be mastered including polymer science, statistical mechanics, computer science, and molecular visualization. Computer programs for performing the simulations will be shared via posting on the CSM Chemical Engineering web pages. Additional dissemination of the results will be accomplished through publication in widely available scientific journals (J. Chemical Physics and Macromolecules) and presentations at national (ACS, APS, AICHE, and SoR (Society of Rheology) and international meetings (Polymer Processing Society, International Congress of Rheology). The commitment to diversity evidenced by past performance by the PI will be continued. In addition to direct support of underrepresented groups as graduate students, outreach activities will be continued. Supported graduate students all participate in MentorNet as a means of providing role models to younger students. The Denver, Colorado region is particularly rich for recruiting Hispanic and Native American students. The PI has worked extensively with students from varied backgrounds, particularly in the context of the NSF supported Research Experience for Undergraduates (REU) program.

1067707Dorgan 在该项目中，使用非平衡分子尺度模拟来加深对制造操作过程中塑料材料流动的理解。所提出的新建模技术可以深入了解不同类型（线性与支化）聚合物及其混合物的流动特性。 为了解决材料设计和聚合物加工中的问题，人们长期以来一直在寻求这种理解。最终，这种理解将导致聚合物类型的最佳组合，从而实现所需的技术目标。 对聚合物流动特性的深入了解提供了一种设计能够提供所需特性的优化添加剂的方法。 为了进行验证，新模拟技术的结果将与新型聚合物结构的现有实验数据进行比较，然后用于设计具有所需加工特性的聚合物混合物。 这项工作的智力价值在于开发计算机代码并为复杂的聚合物系统生成流变数据。 这项工作建立在使用这些相同的模拟技术准确、完整地描述线性结构的熔体流变特性的现有成功的基础上。 除了链结构的影响之外，还研究了对流动的限制影响。 产生的结果可以深入了解纳米技术新兴领域正在利用的新型限制效应。 所开展的活动将研究和教学结合起来，同时促进发现；为了成功完成该项目，必须掌握几个学科，包括高分子科学、统计力学、计算机科学和分子可视化。 用于执行模拟的计算机程序将通过在 CSM 化学工程网页上发布来共享。结果的进一步传播将通过在广泛使用的科学期刊（J.化学物理和高分子）上发表以及在国家会议（ACS、APS、AICHE 和 SoR（流变学会）和国际会议（聚合物加工学会、国际会议）上发表来完成。流变学大会）。除了对代表性不足的研究生群体的直接支持之外，还将继续支持所有研究生。参与 MentorNet 作为向年轻学生提供榜样的一种方式 科罗拉多州丹佛地区特别适合招收西班牙裔和美国原住民学生，PI 与来自不同背景的学生进行了广泛的合作，特别是在 NSF 支持的研究背景下。本科生体验（REU）计划。