Self-healable soft shield for γ-ray radiation based on polyacrylamide hydrogel composites

Abstract

With the growing risk of radiation exposure, there are growing interests in radiation shielding. Because most radiation shields are made from heavy metals, a need to develop a soft shield is raised to protect human body. However, because the shield can easily undergo a mechanical damage by an impact, it would be better to have self-repairing system in the shield. Here, we have fabricated an intrinsic self-healable soft shield for gamma ray by making acrylamide based hydrogel composite. The composite contains lead dioxide nanoparticles for gamma ray shielding and Laponite clays for self-repairing. Although the hydrogel contained a large amount of lead dioxide nanoparticles (3.23 M), the fabricated composites stretched beyond 1400% while showing a high attenuation coefficient of 0.1343 cm−1 against gamma ray from a cobalt-60 source. Then a systematic study was performed to analyze self-healing properties and the 96.55% of maximum self-healing efficiency was obtained. We also analyzed a storage modulus of hydrogel and molecular weight of polyacrylamide to study an effect of gamma ray on the self-healing. The self-healing efficiency was decreased by a gamma ray because the radiation induces scissioning or covalent crosslinking in the chains.

Self-healing polyacrylamide (PAAm) gels at room temperature based on complementary guanine and cytosine base pairs

“…S8 (ESI†). 36,37,42,44,45 It can be found from the results that the self-healing gel prepared in this work has good strain, and the self-healing efficiency is also higher than those reported in some studies (Table S3, ESI†).…”

Dual X-ray- and Neutron-Shielding Properties of Gd2O3/NR Composites with Autonomous Self-Healing Capabilities

“…Nonetheless, despite having Gd 2 O 3 contents of up to 100 phr, the recoverable strengths of the Gd 2 O 3 /NR composites were in the range of 0.30–0.40 MPa, which were in the same order of magnitude as that of pristine NR reported by Xu et al (being in the range of 0.5–0.7 MPa, depending on self-healing times [ 23 ]), implying the useability and potential of the current self-healing materials for applications in radiation protection. Furthermore, the success of the current work could promote further attempts to develop ‘smart’ and more effective materials for use in radiation shielding, along with the previously reported composites of Bi 2 O 3 /PVA, Sm 2 O 3 /PVA, Gd 2 O 3 /PVA, graphene/PVA, and PbO 2 /acrylamide [ 18 , 28 , 49 , 50 ]. It should be noted that the %Recovery values of the NR samples with the addition of Gd 2 O 3 were higher than that of the pristine NR because the original Gd 2 O 3 /NR composite had 2–3 times lower tensile strength than pristine NR, while having similar recoverable strength after self-healing, which resulted in considerably higher %Recovery values for the Gd 2 O 3 /NR composites.…”

Practical Applications of Self‐Healing Polymers Beyond Mechanical and Electrical Recovery

“…In 2020, the Sun group reported an intrinsic self‐healable soft shield for γ‐rays by preparing a polyacrylamide‐based hydrogel composite containing lead dioxide nanoparticles for shielding and Laponite clay for self‐healing mediated by hydrogen bonding. [ 88 ] The particles were incorporated into the stock of the acrylamide monomer and nanoclay, and polymerization was subsequently conducted using a thermal radical initiator (Figure 7c ). The physical cross‐linking of polyacrylamides with clays via hydrogen bonding imparted self‐healing properties.…”

“…The red dotted line indicates the minimum detrimental 𝛾-ray radiation dose to humans. Reproduced with permission [88]. Copyright 2020, Springer Nature.…”