STTR Phase II: Nanofiber Fabrication via Melt Coextrusion for Fuel Filter Membranes

这个小企业技术转让第二阶段项目的更广泛的影响/商业潜力是展示一种低成本、环保的共挤出制造方法，用于生产高表面积的基于微纤维和纳米纤维的非织造燃料过滤器片材。 所述微-/微-非织造结构由两种不同的亲水性和疏水性聚合物在熔融共挤出和随后的剥离加工步骤中制成。 所得多孔过滤介质片材已显示出具有与目前使用的商业燃料过滤器产品相当的上级强度、可定制的孔径和燃料过滤效率。 这些成就标志着一条通往高度可扩展的制造工艺的道路，用于生产低成本的热塑性过滤器产品，以解决日益严格的EPA对ppm级水污染物的规定。据估计，熔融共挤出中降低的制造工艺复杂性在扩大到商业生产量时可降低高达60%的生产成本。此外，一个显着的环境影响，将实现通过采用这种新的生产技术在竞争过程中，由于其？更绿？无溶剂制造方面，消除了每年需要数百万加仑的有机溶剂和支持回收设备目前使用的过滤行业在创建静电纺丝和湿法复合非织造过滤介质。该第二阶段研究项目的目标是制造纳米/微米尺度的非织造纤维过滤垫的燃料过滤器通过一种新的熔融共挤出方法，具有高的燃料/水过滤效率和上级机械性能，在商业上相关的生产规模，以解决严格的EPA 2010过滤法规及其即将在2015年修订。在I期STTR项目中制造的第一代过滤器原型的表面积增加了10倍，孔隙率增加了2倍，变形强度是商业过滤器的6倍。共挤出的微孔过滤纤维尺寸分布与商业熔喷工艺样品相当，并且上级优于领先的湿法成网技术样品。在相同的测试条件下，与使用商业过滤器的80%的水分离相比，在共挤出微纤维过滤介质原型上的初步过滤效率实验显示出60%至大于80%的水与超低硫柴油的分离。新型多层共挤出过滤介质加工技术的商业利益集中在识别新型过滤介质膜聚合物材料，实现纳米尺寸的孔分布以提高过滤效率，并通过改进的过滤膜加工技术实现规模化生产成本节约。

The broader impact/commercial potential of this Small Business Technology Transfer Phase II project is to demonstrate a low cost, environmentally friendly co-extrusion fabrication method for producing high surface area micro- and nanofiber based nonwoven fuel filter sheets. The micro-/nanofiber nonwoven structures are fabricated from two different hydrophilic and hydrophobic polymers in a melt co-extrusion and subsequent exfoliation processing step. The resulting porous filtration media sheets have been shown to possess superior strength, tailorable pore sizes, and fuel filtration efficiency on par with currently utilized commercial fuel filter products. These accomplishments signify a path forward to a highly scalable manufacturing process for producing low cost thermoplastic filter products in addressing the increasingly stringent EPA regulation of ppm level water contaminant. The reduced manufacturing process complexity in melt co-extrusion is estimated to provide up to 60% reduced production costs when scaled to commercial production quantities. Additionally, a significant environmental impact will be realized through adoption of this novel production technology over competitive processes owing to its ?greener? solvent-free manufacturing aspects that eliminates the annual need for millions of gallons of organic solvents and supporting reclamation equipment currently utilized by the filtration industry in creating elctrospun and wet-laid composite nonwoven filtration media.The objectives of this Phase II research project are to fabricate nano/micro scale nonwoven fibrous filter mats for fuel filters via a novel melt co-extrusion approach, with high fuel/water filtration efficiency and superior mechanical properties, in a commercially relevant production scale, towards addressing the stringent EPA 2010 filtration regulations and its upcoming revisions in 2015. The first generation filter prototypes fabricated in Phase I STTR program exhibited up to a ten-fold increase in surface area, up to a two-fold increase in porosity and up to a six-fold the deformation strength of the commercial filters. The coextruded microporous filter fiber size distribution was comparable to a commercial melt-blown process sample and superior to the leading wet-laid technology samples. Preliminary filtration efficiency experiments on the coextruded micro-fiber filtration media prototypes exhibited 60 to greater than 80 % separation of water from ultra-low sulfur diesel as compared to 80 % water separation using commercial filter under same testing conditions. The commercial interest for the new multilayered, coextruded filtration media processing technique is centered on identification of new filtration media film polymer materials, achieving nano-sized pore distributions for improved filtration efficiency and achieving scale-up production cost savings through the improved filter film processing technique.