SBIR Phase I: Natural Fiber-Reinforced Bio-Based Thermoset Resin Composites

该小型企业创新研究第一阶段项目将开发适用于车辆（汽车，公路卡车和休闲车）外部应用的天然纤维增强生物基树脂复合材料。这些生物基工程材料对汽车和卡车制造商来说很有趣，因为它们重量轻，潜在的低成本和低环境影响。然而，这些复合材料往往对水分高度敏感。这种敏感性是生物基复合材料商业化的主要障碍之一。目前，没有天然纤维增强复合材料被用作运输应用中的结构部件，因为湿度敏感性问题。该方法是研究纤维类型，纤维加工和树脂化学的组合，以生产具有强界面结合和对水分最不敏感的性能的复合材料。将确定纤维的类型（洋麻与亚麻）、纤维的加工（原纤化程度和表面改性）以及树脂的类型（大豆油衍生树脂与改性酚醛树脂）如何影响复合材料的机械性能及其对水分的敏感性。预计在这个实验空间内将产生树脂和纤维之间的良好界面结合的组合，这将导致降低湿度敏感性。天然纤维和生物基树脂有可能在各种复合材料应用中取代玻璃纤维和源自石油的合成树脂。最有可能的机会将出现在运输部门（汽车、卡车、房车）;其他机会可能出现在建筑材料（底层地板、屋顶、甲板、柱子和横梁）。用天然纤维增强生物基热固性树脂复合材料代替玻璃纤维增强合成树脂复合材料将具有许多传统复合材料无法比拟的优点。生物基复合材料将具有较低的密度、可接受的比强度、相等或更高的比模量，以及非研磨性的并且具有低的工具磨损率的纤维。它们对环境的影响将较小，因为它们是可再生资源，在制造纤维时使用较少的不可再生能源。将有一个重量减轻，这可以提高燃油经济性和减少排放，以及减少生命周期的环境影响，通过螯合碳在植物材料的生长。由于这些是可再生资源，并且在工业生产水平上具有较低的原材料成本，因此该产品将具有较低的成本。天然纤维和生物基树脂可以与合成纤维和树脂组合以提供设计灵活性，例如，如果天然纤维增强复合材料的刚度对于应用来说是不够的，则可以加入玻璃纤维（10 - 30重量%）以将模量提高到可接受的水平。人们仍然认识到自然强化的大部分价值。同样地，生物基树脂可以用于扩展石化树脂，就像乙醇与汽油混合一样。

This Small Business Innovation Research Phase I project will develop natural fiber-reinforced bio-based resin composites that are appropriate for use in exterior applications on vehicles (automobiles, over-the-road trucks, and recreational vehicles). These bio-based engineering materials are interesting to automotive and truck manufactures because of their light weight, potential low cost, and low environmental impact. However, these composites tend to be highly sensitive to moisture. That sensitivity is one of the main barriers to commercialization for bio-based composites. Currently, no natural fiber-reinforced composites are used as structural components in transportation applications because of the moisture sensitivity issue. The approach is to investigate combinations of fiber type, fiber processing, and resin chemistry to produce composites with strong interfacial bonding and properties that are the least sensitive to moisture. It will be determined how the type of fiber (kenaf vs. flax), the processing of the fiber (degree of fibrillation, and surface modification), and the type of resin (soybean oil-derived resins vs. modified phenolics) affect the mechanical properties of the composites and their moisture sensitivity. It is anticipated that within this experimental space will be combinations that produce good interfacial bonding between resin and fiber which will lead to reduced moisture sensitivity.Natural fibers and bio-based resins have the potential to replace fiberglass and synthetic resins derived from petroleum in a variety of composite applications. The most likely opportunities will be in the transportation sector (automotive, truck, RV); additional opportunities may develop in building materials (subfloor, roof, decking, posts and beams). Replacing fiberglass-reinforced synthetic resin composites with natural fiber-reinforced biobased thermoset resin composites will have the many advantages over traditional composites. The bio-based composites will have lower density, acceptable specific strength, equal or higher specific modulus, and fibers that are non-abrasive and have low wear rates for tooling. Their environmental impact will be less as the are renewable resources and use less non-renewable energy in making the fibers. There will be a weight reduction which can increase fuel economy and reduce emissions as well as reduce the life-cycle environmental impact by sequestering carbon during the growth of the plant material. This product will have a lower cost due to the fact that these are renewable resources and have a lower cost of raw materials at industrial production levels. Natural fibers and bio-based resins can be combined with synthetic fibers and resins to provide design flexibility, e.g., if the stiffness of a natural fiber-reinforced composite is insufficient for an application, fiberglass (10-30 wt%) can be added to raise the modulus to an acceptable level. One still realizes much of the value of the natural reinforcement. Likewise, bio-based resins can be used to extend petrochemical resins much as ethanol is blended with gasoline.