SBIR Phase I: Interface Control in Vapor-Grown Carbon Fiber/Polymer Composites

这个小企业创新研究第一阶段项目的目的是发展的理解和修改的表面状态，表面化学，并为气相生长的碳纤维复合材料中的界面控制上浆的发展。与脆性基质复合材料相比，聚合物基质复合材料通常需要高度的纤维-基质粘合以提供良好的复合材料强度和韧性。大多数商业增强纤维（碳和玻璃两者）在制造期间或之后用各种表面处理以及上浆处理以增加与基质聚合物的相容性和粘合。 一种新型的碳纤维已经开发出来，并正在进行中试规模的生产。这种气相生长碳纤维（VGCF）有望以显著低于其他碳纤维的成本获得高度石墨化的纤维增强。然而，由于这种纤维的高石墨化，纤维表面通常是不反应的，并且不会与聚合物基质结合。因此，将评估各种处理在聚合物基复合材料中使纤维/基体结合的效果。具体地说，在纤维上进行不同程度的表面氧化，然后施加商业上浆剂。将对表面化学进行量化，并通过复合材料测试进行验证。 作为一种低成本纤维，VGCF可以潜在地用作许多弹性体和聚合物基体的复合增强材料。低纤维-基质粘附性问题的解决方案将允许开发至少一种用于汽车部件的商业上可行的材料、需要EMI屏蔽的材料和需要小直径纤维的创新复合材料。

This Small Business Innovation Research Phase I project is aimed at developing an understanding of and modifications to the surface state, surface chemistry, and development of sizings for vapor-grown carbon fibers for interface control in composites. In contrast to brittle matrix composites, polymer matrix composites generally require a high degree of fiber-matrix adhesion in order to provide good composite strength and toughness. The majority of commercial reinforcing fibers, both carbon and glass, are treated during or after manufacture with various surface treatments as well as a sizing to increase compatibility with and bonding to the matrix polymer. A new class of carbon fiber has been developed and is being produced in pilot scale quantities. This vapor-grown carbon fiber (VGCF) holds the promise of a highly graphitic fiber reinforcement at costs significantly lower than other carbon fibers. However, due to the high graphitization of this fiber, the fiber surface is generally unreactive and will not bond with polymer matrices. Thus, various treatments will be evaluated for their effect in enabling fiber/matrix bonding in polymer matrix composites. Specifically, various degrees of surface oxidation will be effected onto the fibers followed by application of commercial sizings. The surface chemistry will be quantified and also verified from composite testing. As a low cost fiber, VGCF can potentially be used as a composite reinforcement for many elastomeric and polymeric matrices. The solution of the problem of low fiber-matrix adhesion will allow for the development of, at least one, commercially viable material for use in automotive parts, materials requiring EMI shielding, and innovative composites requiring small diameter fibers.