Enhanced Plastic with Increased Strength, Flexibility, and Self-Repairing Abilities
A novel plastic material has been engineered, surpassing the strength and elasticity of conventional types. Notably, it exhibits self-healing properties when exposed to heat, retains its original shape, and exhibits partial biodegradability. This innovation, known as VPR, was achieved by introducing polyrotaxane molecules into an epoxy resin vitrimer, a specific plastic variant. The resulting material, VPR, maintains its structural integrity and forms robust internal chemical bonds even at lower temperatures. This our review on the novel “Enhanced Plastic with Increased Strength, Flexibility, and Self-Repairing Abilities”.
Author:
Atir Naeem Qurashi
LinkedIn: Click here to see Atir’s profile
Researchers at the University of Tokyo have developed an innovative plastic material that surpasses the strength and flexibility of conventional plastics. This remarkable material, known as VPR, is capable of self-healing through heat, retaining its original shape, and is partially biodegradable. The creation of VPR involved the incorporation of polyrotaxane molecules into an epoxy resin vitrimer, a specific type of plastic.
At lower temperatures, VPR maintains its structural integrity with robust internal chemical bonds. However, when exposed to temperatures exceeding 150 degrees Celsius, these bonds recombine, allowing the material to be reshaped into different forms. Furthermore, applying heat and a solvent can break down VPR into its raw components. Interestingly, submerging VPR in seawater for 30 days resulted in a 25% biodegradation rate, with the polyrotaxane breaking down into a food source for marine life.
This innovative material holds promise for a wide range of applications, contributing to a more circular economy that promotes resource recycling and waste reduction. Its potential applications span across various fields, including engineering, manufacturing, medicine, and sustainable fashion.
While global initiatives to reduce plastic consumption and waste are underway, it remains a pervasive material that’s challenging to escape. Plastic is omnipresent, found in a wide array of products ranging from toys, clothing, and household items to electronics, vehicles, and infrastructure. Despite its utility, the plastic life cycle and disposal present a multitude of challenges. The development of alternatives that offer greater durability, enhanced reusability and recyclability, or are sourced from environmentally friendly materials, is imperative for addressing these issues and advancing progress toward achieving multiple Sustainable Development Goals set by the United Nations.
Taking this into consideration, a team of researchers from the University of Tokyo has introduced an environmentally sustainable plastic, centered around an epoxy resin vitrimer. Vitrimer plastics represent a relatively recent category of materials. They exhibit the solidity and strength characteristic of thermoset plastics, commonly employed in the production of heat-resistant tableware at lower temperatures. Moreover, vitrimers display the versatility of thermoplastics, allowing them to be reshaped multiple times at higher temperatures, similar to the plastics used for manufacturing plastic bottles. However, vitrimers have a notable drawback in that they tend to be brittle and lack significant elasticity.
To address this limitation, the research team incorporated a molecule known as polyrotaxane into the vitrimer structure, resulting in a substantially enhanced version they aptly named VPR, signifying ‘vitrimer incorporated with polyrotaxane’.
Project Assistant Professor Shota Ando from the Graduate School of Frontier Sciences stated that VPR exhibits remarkable properties, surpassing a standard epoxy resin vitrimer in multiple aspects. Specifically, VPR is more than five times as resilient to fractures, demonstrates self-repair capabilities 15 times faster, swiftly restores its original shape twice as expeditiously, and can be chemically recycled 10 times more rapidly than a conventional vitrimer. Notably, VPR also offers the novel feature of safe biodegradation in marine environments.
Polyrotaxane has garnered significant attention in both the scientific and industrial communities due to its remarkable capacity to enhance the durability of various materials. In this study, the heightened toughness of VPR enabled the creation and retention of more intricate shapes, even under low-temperature conditions, as exemplified by the origami crane featured in the accompanying video.
Furthermore, when it comes to disposal or recycling, VPR offers notable advantages over vitrimers lacking polyrotaxane. As Professor Ando explained, ‘Although this resin remains insoluble in various solvents at room temperature, it can be readily broken down to its elemental components when immersed in a specific solvent and heated.’ Notably, when exposed to seawater for 30 days, VPR displayed a remarkable 25% biodegradation rate, a feature not observed in vitrimers without polyrotaxane. These attributes position it as an ideal material for today’s society, which places significant emphasis on resource recycling and sustainability.
From various domains including engineering, fashion, robotics, and medicine, the research team envisions a wide spectrum of practical and creative applications for VPR. As Professor Ando illustrated, the potential applications are diverse and promising. For instance, in the realm of infrastructure, where materials like epoxy resins are often combined with substances such as concrete and carbon for road and bridge construction, the integration of VPR could yield easier maintenance due to its enhanced strength and heat-induced self-healing properties.
Moreover, VPR offers a unique advantage compared to conventional epoxy resins; it combines hardness with elasticity, making it suitable for robust bonding of materials with varying hardness and elongation. This attribute is particularly valuable in the manufacturing of vehicles.
Furthermore, given its shape memory, shape adjustment, and shape restoration capabilities, there is exciting potential for reshaping clothing items at home using simple tools like a hair dryer or steam iron, offering a novel dimension to fashion customization.
The team’s forthcoming endeavors include collaborating with companies to assess the practicality of their diverse concepts for VPR while persisting with their ongoing laboratory research. Professor Ando shared his perspective, stating, ‘I’ve long held the belief that existing plastics present formidable challenges in terms of recovery and disposal due to their segmentation based on specific applications. An ideal scenario would involve addressing numerous global challenges through the utilization of a singular material, such as this one.”
Also Read: The Cosmic Significance of Chemistry: Exploring Its Role in Our Lives
Follow Us on
References:
- Shota Ando, Masaki Hirano, Lisa Watakabe, Hideaki Yokoyama, Kohzo Ito. Environmentally Friendly Sustainable Thermoset Vitrimer-Containing Polyrotaxane. ACS Materials Letters, 2023; 3156 DOI: 10.1021/acsmaterialslett.3c00895
- www.sciencedaily.com