Effect of some inorganic particles on the softening dispersion of the dynamics of butyl rubber

Damping Analysis of Some Inorganic Particles on Poly(butyl-methacrylate)

Viscoelastic polymers can be used as damping materials to control unexpected vibration and noise through energy dissipation. To investigate the effect of an inorganic filler on damping property, a series of inorganic particles, Ferriferous oxide(Fe₃O₄), Graphene/Fe₃O₄(GF), and Fe₃O₄ of demagnetization(α-Fe₂O₃) were incorporated into poly(butyl-methacrylate) (PBMA). The effects of the dispersion of particles, as well as the interaction between particles and the PBMA matrix on the damping property of composites, were systematically studied. Results revealed that the addition of three types of particles can effectively improve the damping properties and broaden the effective damping temperature range. Dispersion of α-Fe₂O₃ in the PBMA matrix is better than that of Fe₃O₄. As a result, the damping peak can be increased more. The interaction between GF and the PBMA matrix is stronger than that between Fe₃O₄ and the PBMA. The damping peak of the composites can be suppressed by GF, which is opposite to Fe₃O₄ and α-Fe₂O₃. In addition, glass transition temperature (T_g) of all composites in the study shifted to low temperatures.

Improving Thermo-Oxidative Stability of Nitrile Rubber Composites by Functional Graphene Oxide

Graphene oxide (GO), modified with anti-aging agent p-phenylenediamine (PPD), was added into nitrile rubber (NBR) in order to improve the thermo-oxidative stability of NBR. The modification of GO and the transformation of functional groups were characterized by Fourier transform infrared spectroscopy (FTIR), Raman, and X-ray diffraction (XRD). Mechanical performances of NBR composites before and after the thermo-oxidative aging were recorded. The results of dynamic mechanical analysis (DMA) show an increased storage modulus (G’) and a decreased value of area of tan δ peak after introducing modified GO into NBR. It indicates that filler particles show positive interaction with molecular chains. The thermo-oxidative stability of composites was investigated by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). Then, the thermo-oxidative aging kinetic parameters were obtained by the Flynn–Wall–Ozawa (FWO) equation. The results of aging tests show that the thermo-oxidative stability of rubber matrix increases obviously after introducing GO–PPD. In addition, mechanical properties (tensile strength and elongation at break) of both before and after aged NBR/GO–PPD composites were superior to that of NBR. This work provides meaningful guidance for achieving multifunction thermo-oxidative aging resistance rubber composites.

Aging-Resistant Functionalized LDH⁻SAS/Nitrile-Butadiene Rubber Composites: Preparation and Study of Aging Kinetics/Anti-Aging Mechanism

With the aim of improving the anti-aging properties of nitrile-butadiene rubber (NBR), a functional organic filler, namely LDH⁻SAS, prepared by intercalating 4-amino-benzenesulfonic acid monosodium salt (SAS) into layered double hydroxides (LDHs) through anion exchange, was added to nitrile-butadiene rubber (NBR), giving the NBR/LDH⁻SAS composites. Successful preparation of LDH⁻SAS was confirmed by XRD, TGA and FTIR. LDH⁻SAS was well dispersed in the NBR matrix, owing to its strong interaction with the nitrile group of NBR. The obtained NBR/LDH⁻SAS composites exhibited excellent thermo-oxidative aging resistance as shown by TGA-DSC. Further investigation by ATR-FTIR indicated that SAS can capture the radical groups, even during the aging process, which largely accounts for the improved aging resistance.

Influence of graphene/ferriferrous oxide hybrid particles on the properties of nitrile rubber

Graphene/Fe₃O₄ hybrid particles synthesized by co-precipitation can be finely dispersed in NBR as fewer-layered sheets, resulting in great improvement on mechanical property of NBR composite even at very low filler content.