LT: Models and Instruction for Life Cycle Material Content Decisions

9727209斯图尔特本提案侧重于通过开发聚合物降解模型、产品特性模型和生命周期材料含量决策模型来实现可持续发展和材料再利用设计的工程方法。由于这些挑战是多学科的，因此描述了化学工程(聚合物加工)、工业工程(制造工艺)、运筹学(应用数学建模)和机械工程(产品设计)之间的合作。这项建议的一个重要内容是将具有环境意识的工程学方法纳入本科生和研究生工程学课程。随着运输、航空航天和耐用品行业对塑料的需求不断增加，塑料的处置也在增加。分析生命周期中回收塑料的使用、可回收性、减少工艺废物、能源消耗、产量和产品性能之间的权衡是复杂的。到目前为止，大多数公司要么加工100%的原始材料，要么加工少量再研磨的原始材料。纯再生胶的来源可以是内部的，也可以是来自其他工业加工机的(S)。接受产品管理的公司正在努力开发可行的方法，以经济地处理和回收退回的产品。消费后的聚合物暴露在各种热和机械条件下。此外，消费后产品含有聚合物混合物以及增强剂、油漆或阻燃剂等添加剂。因此，消费后塑料给制造过程带来了额外的原材料不确定性。为了实现从摇篮到摇篮产品的企业可持续发展目标，生产先进聚合物和复合材料的公司需要聚合物降解模型、产品表征模型和可回收材料含量选择的决策工具，以及了解可持续发展问题和方法的工程师。必须解决几个材料、制造、设计和决策建模问题以及课程整合。首先，我们必须能够确定进口回收材料的降解程度。以前的研究已经证明了分子量分布(MWD)与聚合物降解性能之间的关系，如粘度和熔体指数。我们将研究测量常见材料混合物的MWD的可行性，其中混合物指的是不同的回收世代(从原始到第五代)以及聚合物混合物。我们还必须描述产品的复杂性和所需的相应材料特性。接下来，我们将研究产品复杂性与材料降解性能之间的关系。将使用温度和压力的典型工业处理参数。其目标是表征回收含量与原始含量之间的比率与模具几何形状、机械性能和流变性之间的关系。材料降解模型将为生命周期材料含量决策模型提供有价值的输入。生命周期材料含量决策模型的目标是选择材料含量比率，以便在再研磨、消费后和原始材料供应、能源消耗、周期时间和质量的限制下将成本降至最低。在五个不同的本科生和研究生课程中，主要研究人员将激励未来的工程师努力应对环境材料选择的挑战。工业生态学原理以及生命周期材料内容决定的分析方法将被整合到工程课程中。***

9727209 Stuart This proposal focuses on engineering approaches for sustainability and design for materials reuse through the development of polymer degradation models, product characterization models, and life cycle material content decision models. Because these challenges are multidisciplinary, collaboration between Chemical Engineering (polymer processing), Industrial Engineering (manufacturing processes), Operations Research (applied mathematical modeling), and Mechanical Engineering (product design) are described. An important element of this proposal is the integration of environmentally conscious engineering approaches into undergraduate and graduate engineering curriculum. As the demand for plastics by the transportation, aerospace, and durable goods industries is increasing, the disposal of plastics is also increasing. The analysis of life cycle trade-offs between use of recycled plastics, recyclability, reduction of process wastes, energy consumption, yields, and product performance are complex. To date, most companies process either 100% virgin material or virgin material with small percentages of regrind. Sources of pure regrind may be internal or from another industrial processor(s). Companies embracing product stewardship are struggling to develop viable approaches to economically process and recycle returned products. Post-consumer polymers have been exposed to various thermal and mechanical conditions. In addition, post-consumer products contain polymer blends as well as additives such as reinforcements, paint, or flame retardants. Thus, post-consumer plastics introduce additional raw material uncertainties into the manufacturing process. To achieve corporate sustainability goals for cradle to cradle products, companies producing advanced polymers and composites need polymer degradation models, product characterization models, and decision tools for recycled material content choices as well as engineers who understand sustainability issues and approaches. Several materials, manufacturing, design, and decision modeling issues as well as curriculum integration must be addressed. First, we must be able to identify the measure of degradation for incoming recycled materials. Previous studies have demonstrated the relationship between the molecular weight distribution (MWD) and polymer degradation properties such as viscosity and melt index. We will investigate the feasibility of measuring the MWD for common material mixes where mixes refer to various recycling generations (virgin through fifth generation) as well as polymer blends. We must also characterize the product complexities and the corresponding material properties required. Next, we will investigate the relationship between the product complexities and the material degradation properties. Typical industrial processing parameters for temperature and pressure will be used. The goal is to characterize the relationship between the ratio of recycled content to virgin content and the mold geometry, mechanical properties, and rheological properties. The materials degradation models will provide valuable input for the life cycle material content decision model. The objective of the life cycle material content decision model is to select material content ratios in order to minimize costs subject to constraints on regrind, post-consumer, and virgin material supply, energy consumption, cycle time, and quality. In five different undergraduate and graduate classes, the principal investigators will motivate future engineers to grapple with environmental materials selection challenges. Industrial ecology principles as well as analytical methods for life cycle material content decisions will be integrated into the engineering curriculum. ***