Novel high performance lubricants for industrial and biomedical applications

新一代润滑剂的开发具有重要的技术和经济意义，因为据估计，我们的能源消耗有一半是以摩擦的形式消散的。 液晶(LCS)是一种各向异性粘弹性材料，类流体流动和类晶体各向异性的结合使其相作为界面行为的改进剂应用于润滑剂。粘度系数相对于不同流动方向的各向异性是液晶相的独特性质。液晶材料能够形成具有良好承载能力的有序边界层，降低滑动表面的摩擦系数、磨损率和接触温度，从而有助于提高部件的使用寿命和节约能源，已被广泛证明。 另一种显著改善润滑剂性能的方法是添加纳米颗粒。这些添加剂能够形成具有良好承载能力的有序边界层，降低滑动表面的摩擦系数、磨损率和接触温度。 虽然人工滑膜关节的性能和寿命总体上是良好的，但润滑仍然是一个关键因素，因为其失效的主要形式之一是由于磨损颗粒导致的植入物松动。很少有直接证据表明健康和患病滑液的组成以及这种生物液体的结构和性质所起的作用。如果我们理解了这一点，我们可能能够设计出更好的人工关节，甚至可能修复受损的自然关节。由于大多数溶致液晶材料的生物相容性，它们被认为是用作生物润滑剂的可行候选材料。 该研究项目的主要目标是设计、测试和优化具有超低摩擦和减磨的新一代润滑剂和生物润滑剂。计算模拟和实验将为研制经济可行的新型润滑剂提供一条有效的途径。为了提高润滑效率，从而降低能源消耗，我们的目标是开发一种使用液晶或纳米颗粒作为添加剂的润滑流动模型，该模型经过实验验证，可以应用于现代计算工程和设计工具中。这些工具将使设计下一代可持续高性能润滑油成为可能。

The development of a new generation of lubricants is of paramount technological and economic relevance as it is estimated that half of our energy consumption is dissipated as friction. Liquid Crystals (LCs) are anisotropic viscoelastic materials; the combination of fluid-like flow with crystal-like anisotropy makes its phases interesting as modifiers of interfacial behavior when applied as lubricants. The anisotropy of the viscosity coefficient, with respect to different flow directions, is a unique property of the liquid crystalline phase. The ability of liquid crystalline materials to form ordered boundary layers with good load-carrying capacity, and to lower the friction coefficients, wear rates and contact temperatures of sliding surfaces, thus contributing to increase the components service life and save energy has been widely demonstrated. Another method to improve significantly the properties of lubricants is the addition of nanoparticles. The ability of these additives to form ordered boundary layers with good load-carrying capacity, and to lower the friction coefficients, wear rates and contact temperatures of sliding surfaces has been demonstrated. Although the performance and life of artificial synovial joints is generally good, lubrication remains a key factor because one of the main forms of their failure is due to loosening of the implant caused by wear particles. There is very little direct evidence for the role played by the composition of the healthy and diseased synovial fluid and the structure and properties of this biofluid. If we understood this we might be able to design better artificial joints and possibly even repair damaged, natural joints. Due to the bio-compatible nature of most lyotropic liquid crystalline materials, they have been considered as viable candidates to be used as bio-lubricants. The main objective of this research program is the design, testing and optimization of a new generation of lubricants and bio-lubricants with ultra-low friction and reduced wear. The computational modeling and experiments will offer an efficient pathway to formulate novel lubricants which are economically viable. To improve lubrication efficiency and therefore reduce energy consumption we aim to develop a model of lubrication flow using liquid crystals or nanoparticles as additives that is experimentally validated and can be implemented into modern computational engineering and design tools. These tools will make it possible to design the next generation of sustainable high performance lubricants.