SBIR Phase I: Ultra-softening polymers from engineered thiol-based resins for additive manufacturing

This Small Business Innovation Research (SBIR) Phase I project will focus on the understanding, development, and commercialization of new ultra-softening shape memory polymer (SMP) systems for use as novel earpiece materials. Currently, earpieces such as earphones and earplugs utilize tough, semi-rigid polymers that are often poor fitting, uncomfortable and must be produced via conventional molding technology. SMPs possess several key properties that render them attractive alternatives to conventional materials such as their ability to soften dramatically with heat and their ability to be optically cured. Through adjustments in the composition of SMP systems, thermomechanical properties such as the temperature and amount of softening can be significantly and controllably tailored according to the intended application. The softening that the earpieces experience after insertion will result in the ability to conform to the exact shape of the ear canal, improving comfort and audio performance. Pending success of this project, we will have developed the first shape memory material that can be rapidly cured with light into complex 3-D shapes with sub 100 micrometer feature sizes using stereolithography, which is viscoelastic at both room temperature and body temperature and softens an order of magnitude between the two. The broader impact/commercial potential of this project is built around the fact that we are introducing a completely new technology which will enable real time manufacturing of custom components with application specific thermomechanical properties. While the overarching goals of this proposal are specific to demonstrating custom ultra-softening viscoelastic earpieces with superior comfort and audio quality with easy insertion, the technology developed here will benefit numerous industries and society as a whole. For example, we envision this technology being used in remote locations where businesses have need for softening elastic and viscoelastic materials in specified geometries such as gaskets, heat-shrinkable tubes, seals, grips, etc. Furthermore, this technology could be monumental in the medical field by enabling hospitals to create custom biomedical devices on-site as needed, designed specifically for the patient. Eliminating the need to order specialty parts from a separate location will reduce time and cost associated with medical device implantation. In addition, a successful project will benefit the scientific community by providing peer reviewed publications introducing novel shape memory material with highly tailorable thermomechanical properties according to composition, thus stimulating additional research in field of SMP systems and applications.