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In the present work, biophenol and furfural-based resol resin was synthesized and utilized for the very first time to cure styrene butadiene rubber (SBR). The reaction was studied over a range of times, temperatures, pH, and furfural to biophenol ratios to fix the optimum conditions. Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy revealed the functional groups and chemical structure of the synthesized resin, respectively. An exothermic peak for the resin curing appeared at 143[degrees] C in the differential scanning calorimetry thermogram of the resin. Then, the biophenol-furfural resin was utilized for the curing of SBR. The synthesized resin increased the tensile strength of the raw rubber from 0.20 [+ or -] 0.01 MPa to 1.22 [+ or -] 0.10 MPa at 10 phr loading, and the crosslink density was 2.56 * [10.sup.-5] mol/mL. The activation energy for curing SBR containing 10 phr resin was 97 kJ/mol. The storage modulus of the resin-cured compound was improved. The glass transition temperature of the raw SBR was also shifted from -43.8 to -42.3[degrees]C when 10 phr resin was used for the curing. Hence, for the first time, this work reported the utilization of biophenol-biosourced furfural resin to cure rubbers. KEYWORDS biobased resin, biophenol-furfural resin, curing, elastomer, orcid.org/0000-00021227-0732 orcid.org/0000-0002-82295353 1 | INTRODUCTION Raw rubber is a soft, high molecular-weight material; compounding with different ingredients improves the performance of the elastomers. Curing is the finishing stage of product [...]

In the present work, uncured and cured properties of high-performance, sustainable Natural Rubber nanocomposites developed by leveraging the unique synergy between carbon black and fibrous nanofillers such as silicon carbide, carbon nanotubes, and aramid nanofibers were investigated. Reinforcement in these composites was analyzed using the properties of the unvulcanized compounds, which were then correlated with those of the vulcanized compounds. A 50% increment was recorded for the bound rubber content of the nanocomposites, which resulted in tremendous improvements in the reinforcement index and tensile strength of the unvulcanized nanocomposites. In contrast, the die swell index came down compared with the control compound. The formation of a percolating network due to the presence of high aspect ratio fibers resulted in a higher Payne effect in hybrid nanocomposites, which was confirmed from the scanning and transmission electron microscopy. The 100% modulus, 300% modulus, and tensile strength of the unvulcanized nanocomposites recorded an improvement of 80,121, and 450%, respectively, by the incorporation of nanofibers. The molecular aspects of reinforcement were elucidated from theoretical calculations using Mooney-Rivlin plots. It was presumed that the improved reinforcing efficiency of the nanofibers resulted from restricted mobility of elastomer chains due to the presence of the dual filler system. KEYWORDS hybrid composites, nanocomposites, rheology, synergism, 1 | INTRODUCTION Increasing demand for sustainable materials and technologies has resulted in a desire to replace polymers from fossil fuels with those from renewable sources so that the needs [...]

Flexible polymeric materials including dielectric thermal interface materials (TIMs) used in integrated circuits and other high frequency applications are exposed to extreme thermal and electrical conditions during their service life. Insight into the in‐use thermal stability and material lifetime is valuable to maintaining performance durability and preventing premature failure in actual end use. Herein, the thermal stability of polytetrafluoroethylene (PTFE), modified PTFE and their nanocomposites with recent generation boron nitride nanobarbs (BNNBs) was investigated based on lifetime prediction from thermogravimetric analysis and tensile strength deterioration of heat‐aged samples. Additionally, thermal degradation kinetics and mechanism was investigated using the model‐free advanced isoconversional method based on changing activation energy. The result shows that BNNB extends the lifetime of the PTFE by an order of magnitude. The degradation mechanism proposed from TGA‐MS result is supported by the multistep degradation mechanism identified in the kinetic computation. These results are valuable for predicting materials' in‐use lifetime to avoid premature failure. [ABSTRACT FROM AUTHOR]

In situ generated nanosilica particles were grafted onto aramid nanofibers while modified with a blocked mercapto silane (3‐Octanoylthio‐1‐propyltriethoxysilane). Nanofibers were derived from macro aramid fibers (poly (p‐phenylene terephthalamide)). Fourier‐transform infrared spectroscopy and x‐ray photoelectron spectroscopy revealed that the direct condensation reaction between the silane's ethoxy groups and the nanofiber's hydroxyl or carboxylic groups forms SiO‐C bonds. Morphological analysis of nanofibers revealed the formation of nanosilica from unreacted residual silane on the modified nanofiber (A‐NM) surface. In situ silica formation caused SiOSi bond formation, according to the spectroscopic analysis. Styrene butadiene rubber‐silica composites with modified nanofiber additive were prepared. The bound rubber content and filler flocculation rate displayed an improvement in nanofiber dispersion and rubber‐nanofiber interaction after silane modification. Mechanical characteristics of the composites improved after rubber and modified nanofiber interaction, dispersion, and strengthening. The nanofibers evenly distributed during mixing, as proven by morphological analysis of composites. Incorporation of 1 phr of A‐NM increased tensile strength by 16% and abrasion resistance by 3.1%. Composite's rolling resistance indicator (6.2%) and winter traction indicator increased at high temperatures with 1 phr of A‐NM loading. This specialized filler decorated nanofibers could be used as energy‐efficient tire additives as an alternative to other trendy commercial materials. [ABSTRACT FROM AUTHOR]

3-Octanoylthio-l-propyltriethoxysilane (a new silane) grafted styrene butadiene rubber/ silica composites were prepared in the present work, where grafting weight percentage of the base rubber (0%, 2%, 4%, and 6%) and filler content of the composites (0, 5, 15, 35, and 50 phr) were varied to investigate dispersion of the filler in the rubber. A detailed quantitative study of morphology-physical property relationship of the composites using dispersion degree parameter was carried out. Pronounced improvement of dispersion was observed with increasing grafting weight percentage of the base rubber. A mechanism of polymer to filler interaction was shown by Fourier transform infrared spectroscopy. The dispersion rate constant from the torque-time curve increased with the grafting percentage. Bound rubber content and Payne effect measurement indicated improved rubber-filler interaction for the grafted rubber compound. A relation between low strain modulus of the composites and grafting percentage was proposed. The nanoindentation studies gave further insight into the results. Other physico-mechanical properties at different grafting weight percentages at particular filler loading (50 phr) and at different filler loadings at a particular grafting weight percentage (4%) were evaluated. The improved mechanical and dynamic mechanical properties with increasing grafting weight percentage are an indication that this methodology could be used in green tire application. KEYWORDS composites, dispersion, morphology, rubber, silica, 1 | INTRODUCTION Organic-inorganic nanohybrids are investigated nowadays for their extraordinary surface and bulk properties. The inorganic compounds are usually layered clays or nanosilicas or other materials with a wide [...]