The majority of 3D‐printed biodegradable biomaterials are brittle, limiting their application to compliant tissues. Poly(glycerol sebacate) acrylate (PGSA) is a synthetic biocompatible elastomer and compatible with light‐based 3D printing. In this article, digital‐light‐processing (DLP)‐based 3D printing is employed to create a complex PGSA network structure. Nature‐inspired double network (DN) structures consisting of interconnected segments with different mechanical properties are printed from the same material in a single shot. Such capability has not been demonstrated by any other fabrication techniques so far. The biocompatibility of PGSA is confirmed via cell‐viability analysis. Furthermore, a finite‐element analysis (FEA) model is used to predict the failure of the DN structure under uniaxial tension. FEA confirms that the DN structure absorbs 100% more energy before rupture by using the soft segments as sacrificial elements while the hard segments retain structural integrity. Using the FEA‐informed design, a new DN structure is printed and tensile test results agree with the simulation. This article demonstrates how geometrically‐optimized material design can be easily and rapidly constructed by DLP‐based 3D printing, where well‐defined patterns of different stiffnesses can be simultaneously formed using the same elastic biomaterial, and overall mechanical properties can be specifically optimized for different biomedical applications.
One of the environmental crises facing the world is pollution due to rubber auto tire destruction. The use of tires in vehicles consumes 6% of the world's energy and causes 5% of carbon dioxide emissions; it accounts for up to 10% of the microplastic pollution found in oceans. Here, a new rubber nanocomposite self‐assembled from hard and soft elastomer matrixes is designed: polybutadiene with its two hydroxy chain ends reacts with 4,4'‐diphenylmethane diisocyanate to form segmented polyurethane. This system first undergoes self‐assembly, forming well‐defined nanoscale hard domains distributed in the soft matrix. Then, cross‐linking between the soft segments is accomplished by a controlled radiation method, resulting in the double network elastomer (DN‐E). Remarkably, the DN‐E exhibits the lowest reported loss factor value at 60 °C. The index of energy dissipation in the rolling tire demonstrates a prominent reduction of 72%, accomplished with an 88% decrease in energy loss, and 85% less wear loss, as compared with best earlier reported commercial tires. These new double‐network materials open a new prospective for the design and fabrication of ultralow energy‐consumption and strong abrasion‐resistance elastomers, which establishes a milestone for the development of the next generation of green low‐pollution tires causing much less energy dissipation.
more » « less- NSF-PAR ID:
- 10363689
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 30
- Issue:
- 34
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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