Energy dissipating of shear thickening gel reinforced with PVA polymer

The new generation of impact-resistant materials should be lightweight and flexible. For this purpose, various additives, such as shear thickening gels (STG) are synthesized and incorporated into these materials. In this article, it has been tried to develop a new method for synthesizing new shear -thickening gels (n-STG). This new method involves dispersing Polyvinyl alcohol (PVA) solution into the STG polymer matrix. Unlike previous studies that used PDMS, and boric acid as fixed materials in the preparation of STG, this work introduces PVA as a new auxiliary material in the PDMS and boric acid polymer matrix. At first, different percentages of PVA solution in distilled water (DW) were prepared. After a series of experiments, PVA (14%) was well combined with the polymer matrix. In this way, by changing the mass ratio of PVA (14%) to pyroboric acid (P-BA) and PVA (14%) to polydimethylsiloxane (PDMS), 7 values of (1:6) to (7:6) were tested. When the ratio of PVA (14%) to P-BA is greater than 1:6, it lacks STG properties. However, when the ratio of PVA (14%) to PDMS changed from 1:6 to 6:6, shear thickening gel properties were observed and the samples were named n-STG. The maximum shear storage modulus (G'_max) of n-STG samples first increases and then decreases, reaching a maximum value of 0.55 MPa. The resilience elasticity test demonstrated that the rebound percentage value of the n-STG-5 sample was 22.6% higher than the STG sample without PVA, due to its higher shear storage modulus. This study showed that PVA in the STG polymer matrix improves polymer chain cross-linking and performance due to its n-STG stimulus–response property.