Influence of Graphene Oxide Contents on Mechanical Behavior of Polyurethane Composites Fabricated with Different Diisocyanates

Abstract

The exceptional behavior of graphene has not yet been entirely implicit in the polymer matrix. To explore this fact in the present work, two series of Polyurethan (PU) composites were synthesized. The structural modification was observed by the use of two different diisocyanate of methylene diisocyanate (MDI) and hexamethylene diisocyanate (HMDI) in hydroxylterminated polybutadiene (HTPB) by using I,4 Butane diol (BD) as the chain extender. The variation in hard segment up to 25 (wt.%) in both series led to significant changes in the mechanical behavior of graphene oxide (GO) induced composites. Both series were prepared by an in situ polymerization process. Fourier transform infrared (FTIR) analysis showed a peak in the region of 1700 cm−1, which confirmed the conversion of the NCO group into urethane linkages. Thermal gravimetric analysis (TGA) revealed a thermal stability up to 450 °C @ 90% weight loss. The swelling behavior showed the optimum uptake of 30% of water and 40% of dimethyl sulfoxide (DMSO) with aliphatic diisocyanate. The values of storage modulus (E′), complex modulus (E*), and compliance complex (D*) were observed up to 7 MPa, 8 Mpa, and 0.7 MPa−1, respectively. The degree of entanglement (N) values were calculated from DMA and were found in the range of 1.7 × 10−4 (mol/m3). Phase segregation of PU was observed by scanning electron microscopy (SEM), elucidating the morphology of composites.

Graphene Oxide-Doped Polymer Inclusion Membrane for Remediation of Pharmaceutical Contaminant of Emerging Concerns: Ibuprofen

“…The presence of graphene oxide in PIMs' G1-G3 can be observed by the ring structure of the GO as indicated by the peak at 2160 cm −1 [54,55]. Similarly, the peaks at 3380 cm −1 represent the O-H stretching vibration of hydroxyl groups, while the peak of 1630 cm −1 is the C=O unit of -COOH groups stretch band of graphene oxide [56,57]. To evaluate the mechanism of Ibuprofen removal by the optimum graphene doped PIM and at the optimum pH, a comparative infrared spectrum of PIM G3 before and after Ibuprofen extraction was investigated, as shown in Figure 4 Wave number (cm To evaluate the mechanism of Ibuprofen removal by the optimum graphene doped PIM and at the optimum pH, a comparative infrared spectrum of PIM G3 before and after Ibuprofen extraction was investigated, as shown in Figure 4.…”

On the State of Graphene Oxide Nanosheet in a Polyurethane Matrix

“…Moreover, the Young’s modulus increased symbatically with the increasing concentration of the additive, reaching a value of 42.95 MPa, which was almost six times higher than that of the initial PU. In the literature, this behavior is logically associated with physical crosslinking between the rigid domains of the PU matrix and the functional groups on the GO nanosheet surface due to the formation of hydrogen bonds [ 50 , 51 , 52 , 53 , 54 ]. However, IR spectroscopy, which is one of the most effective methods for studying hydrogen bonds, turned out to be insensitive in our case [ 8 ].…”

Asphaltene-Stabilized Polyisobutylene Pressure-Sensitive Adhesives for Ultraviolet Protection and Surface Bonding

“…The most used fillers for PSA are montmorillonite [ 41 , 42 ], silicon dioxide [ 43 , 44 ], and wax [ 45 , 46 ], but some specialized fillers are also possible, e.g., graphene [ 47 ]. The introduction of nanosized fillers can lead to the creation of nanocomposites and the achievement of the most notable changes in the properties of final materials [ 48 , 49 ], and the most significant improvement in the properties occurs when applying nanofillers with anisometric particles, e.g., those that have the shape of plates [ 50 ]: montmorillonite [ 51 , 52 , 53 , 54 ] and graphene [ 55 , 56 , 57 ]. However, the practical use of graphene is significantly limited due to its high price, and there is one more material with flat nanosized particles, attracting the greatest attention of researchers for use in various purposes—asphaltenes [ 58 ].…”