SBIR-STTR Award

This Small Business Innovation Research Phase I project aims to develop a new material and methodology to design comfortable, custom earpieces based on shape-memory polymers. These devices are stand alone earplugs or attachments to products in three other markets - headphones, hands-free and Bluetooth devices, and hearing aids: any aural device that demands comfort and seal. The work focuses on these adaptive self-adjusting materials that conform to complex contours of the inner ear canal, are comfortable and seal well. The intellectual merit of the project is related to developing adaptive earpieces from tailored shape-memory polymers with enhanced acoustic properties. Current material solutions suffer from several drawbacks, including an inability to control the force exerted by the earpiece upon the sensitive regions of the inner ear and concurrently block out unwanted noise. This Phase I project will develop next generation self-adjusting shape-memory polymers that deliver both long term comfort and an effective seal as cost-effective one-size-fits-all devices. This project will also provide overall proof of concept for enhanced devices and generate a fundamental research knowledge base necessary to ultimately produce successful commercial devices. Due to their desirable properties, chemically crosslinked shape-memory polymers are increasingly being proposed in biomedical applications, but their broader adoption into mass markets has been limited. The novel manufacturing process, mnemosynation, developed leading up to this project enables a new class of thermoset polymers with fully recoverable strains that can be mass manufactured through traditional plastics processing techniques. Thus, the broad impact of this project is two-fold: it will lay the groundwork for future injection moldable devices of complex geometries possessing shape memory and it will establish the first links between sound attenuation and crosslinker density in shape-memory polymer earpieces. Better occlusion translates into lower required listening volumes on devices such as earphones, Bluetooth hands free devices and hearing aids. This will be the first commercial proving ground for the mnemosynation manufacturing process and pave the way for a new generation of mass producible customizable ergonomic plastics with tunable shape memory properties. This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5)

This Small Business Innovation Research (SBIR) Phase II project supports the development of a unique manufacturing method to produce novel shape memory polymers in complex shapes. These smart materials can "remember" and reform to a set shape upon an external stimulus. This continuous manufacturing process is vastly more efficient than the current state-of-the-art methods, enabling many low cost applications of shape memory polymers. This project will develop shape memory polymer earplugs that are heat activated by the user's ear and continuously adapt and self-adjust to custom fit any size ear canal. Current material solutions for earplugs suffer from several drawbacks, including an inability to control the force exerted by the earplug upon sensitive inner ear regions that cause pain over time. This effort will address the technical challenges of scaling up the low cost manufacturing process and establish formulations that will enable optimization of its acoustic performance. Human subject testing will be conducted to subjectively validate comfort and objectively validate attenuation with very differently sized ear canals. If successful, this project will yield a device with optimized acoustic properties and comfort ready for first commercial sale. The broader/commercial impact of this project is the impact of a mass-manufactured shape memory polymer device. Due to their desired properties, shape memory polymers are increasingly used in biomedical applications, but their broader adoption into mass markets has been limited by cost and geometry constraints. If successful, this project will establish a novel manufacturing process that, through modified traditional plastics processing techniques, can mass manufacture a new class of polymers. Thus, the broad impact of this project is twofold: it will establish the first links between sound attenuation and crosslinker density in shape memory polymer earpieces, and it will lay the groundwork for future low cost shape memory devices of complex geometries. Better occlusion and more comfortable earplugs are expected to enable higher usage of protective hearing devices in loud industrial settings. This in turn addresses the growing problem of noise-induced hearing loss in the industrial sector, which according to OSHA, is the number one occupational disease in the US today. In addition, shape memory earplugs may benefit other users including musicians, professional athletes and children with autism. This technology can also be adapted to similar devices including cell phone headsets, Bluetooth audio devices, and hearing aids