Physico-mechanical and dynamic mechanical studies of nanographite reinforced chlorobutyl nanocomposites

Abstract

Nanographite reinforced chlorobutyl elastomer (CIIR) nanocomposites were prepared. The dispersion of the nanographite in the CIIR matrix has been investigated by scanning electron microscopy. The effect of increasing nanographite loadings (2, 4, 6 and 8 phr) on mechanical properties like tensile strength, hardness, elongation at break and modulus (100, 200 and 300%) has been studied. The study shows increase in tensile strength, hardness and modulus and decrease in elongation at break with nanographite loading, which can be attributed towards better CIIR-nanographite interaction. The above explanation was again verified from bound rubber measurements. It shows increase in bound rubber contents with nanographite loading. Dynamic mechanical analysis was used to study their relaxation behaviour as a function of temperature (2100 to 100uC) at frequency 1 Hz and 1% strain. The effect of increasing nanographite loadings on glass transition temperature was marginal in all the composites, and Tg value was in the range of 210 to 10uC, which has been explained on the basis of relaxation dynamics of polymer chains in the vicinity of fillers. The effects of variation in nanographite loading and temperature on dynamic mechanical properties like loss tangent, storage and loss modulus have been reported. The effect of solvent (chloroform, benzene and tri-chloroethylene) on swelling properties at different periods of time (15, 30, 45 and 60 min) shows that the degree of swelling increases with time and decreases with concentration of nanographite loading.

Novel application of Zn‐containing Zeolitic Imidazolate Frameworks in promoting the vulcanization and mechanical properties of natural rubber composites

“…Below the glass transition temperature (such as −80°C), the storage modulus was increased with the rise of ZIF‐8 content and the NR composite with D/T/Z8‐1.2 had the highest storage modulus (see the insert curve in Figure 5a). Such an enhancement in modulus may be accredited to the reinforce effect of ZIF‐8 and the effective loading transferred from NR matrix 41 . Above the glass transition temperature (such as 25 and 60°C), the storage modulus depends closely on the crosslink density of the rubber.…”

“…Such an enhancement in modulus may be accredited to the reinforce effect of ZIF-8 and the effective loading transferred from NR matrix. 41 Above the glass transition temperature (such as 25 and 60 C), the storage modulus depends closely on the crosslink density of the rubber. As shown in Table 5, the NR composites with the addition of ZIF-8 had the higher storage modulus than the NR without ZIF-8.…”

Polylactic acid nanocomposites for biomedical applications: effects of calcium phosphate, and magnesium phosphate nanoparticles concentration

“…The higher tan δ value at lower frequency region shows that the damping factor is more pronounce or the loss of energy is more. The decreasing tan δ curve describes the enhancement of PLA's melt behaviour with the incorporation of nanoparticles like Cap and MgP due to a decrease in free volume, which limits the mobility of molecular chains so that the damping value decreases [44, 45]. PLA/MgP nanocomposites show the higher Tan δ values than that of PLA/CaP sample, indicating that the former one dissipates more energy than the later.…”

“…A plot of log (G ′ ) versus log (G ′′ ), also known as the Han plot, describes the miscibility in a polymer matrix, which is either a blend of two or more polymers or a composite [44]. shows an increase in storage modulus, loss modulus, and complex viscosity with both CaP and MgP content.…”

Preparation and characterization of hyperbranched polymer modified montmorillonite/chlorinated butyl rubber damping composites

“…The T g value was in the range of −10 to 10 °C, and the damping temperature range was obviously improved. However, the damping performance had not been greatly improved . In addition, the layered structure of montmorillonite (MMT) was advantageous to increase the interaction between macromolecular chains, and thus can improve the damping performance of polymers.…”