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Silica carbon black (SiCB) was used as a natural carbon-silica dual-phase filler (CSDPF) containing both biochar and silica, which was obtained by pyrolysis of rice husks. The reinforcing performances of SiCB were limited by the large particle size and poor surface activity. In this work, the size and distribution of the SiCB particles were modified by ethanol-assisted milling (S/E), and increase in oxygen-containing groups enhanced the surface activity of SiCB and promoted the grafting of silane coupling agent (Si69). The filler-rubber interfacial interactions were enhanced when the Si69-grafted SiCB (S/E-X, X means the amount of Si69) was used as filler for natural rubber (NR). Compared with the SiCB-filled NR (SiCB/NR), the S/E-3-filled NR (S/E-3/NR) showed 44%, 19%, and 27% improvement in the tensile strength, tear strength, and stress at 300% strain, respectively, and the reinforcing properties have reached the level of commercial carbon black (N774). This study provides a novel way for surface modification of CSDPF and improves the application of rice husk-based materials in rubber composites. KEYWORDS carbon-silica dual-phase filler, ethanol-assisted milling, rice husks, rubber reinforcement, silica carbon black, 1 | INTRODUCTION Reinforcing filler is an important component of rubber composites. Effective fillers not only reduce the production costs but also enhance the mechanical properties of composite materials. [1-3] [...]

This study explores the mechanical and magnetic properties of magnetorheological elastomers (MREs) based on chloroprene rubber, enhanced with carbonyl iron powder (CIP) as the primary filler. Carbon black serves as the primary reinforcing filler, with multi‐walled carbon nanotubes (CNTs) used as a secondary filler to strengthen the rubber matrix. The primary objective of this research is to examine the effects of the mixture of iron powder with reinforcing fillers and the interaction of these fillers with the rubber matrix on the mechanical and magnetomechanical performance of MREs. CNTs, tubular nanoscale carbon molecules, significantly enhance the tensile strength and fatigue resistance when combined with the MRE matrix. During mixing, CNTs form a network structure within the MRE matrix, promoting the dissipation of accumulated heat and reducing thermal fatigue loss. The addition of 20 parts of CNTs to the CR matrix significantly improved the tensile mechanical properties, with the 100% set elongation stress increasing by up to 260% and the magnetic responsiveness increasing by 30.6%. The addition of 10 parts of carboxylated CNTs most notably enhanced the magnetorheological effect, increasing the magnetic stress relaxation rate by 78%. These enhanced properties enable MREs to provide better vibration control and comfort in automotive suspension systems, improve energy absorption and damping effects in industrial damping systems, and enhance durability and sealing performance in sealant applications. Highlights: Carbonyl iron powder, carbon black, and carbon nanotubes (CNTs) were used as fillers to strengthen the chloroprene (CR) matrix magnetorheological elastomers (MREs).CNTs formed a network structure, promoting the dissipation of accumulated heat and reducing thermal fatigue loss.The tensile mechanical property of MRE with 20 parts of CNTs has been significantly improved, with an increasing magnetic responsiveness of 30.6%.Magnetorheological effect of MRE with 10 parts of CNTs has notably enhanced, with the magnetic stress relaxation rate of 78%. [ABSTRACT FROM AUTHOR]

Lignin, a by-product produced during pulping and papermaking, is a phenolrich compound with excellent prospect to be used as a substitute for phenol in phenolic resin adhesive. Phenol-enriched hydroxy depolymerized lignin by microwave alkali catalysis is an effective method to prepare high-adhesive biomass composite. This study investigated the microwave digestion of lignin under different conditions of the alkali catalysis (sodium hydroxide) concentration, power, reaction time, and reaction temperature. The results show that on the condition of sodium hydroxide concentration of 0.3 mol/L, temperature of 170[degrees]C, and time of 20 min, the highest phenolic hydroxy content obtained by depolymerization of lignin is 21.68%. SEM shows that the depolymerized lignin has no original basic constituent units and lignin-based phenolic resin has dense uniform pine needle units. Therefore, it has a high bonding strength of 1.934 MPa. The bonding strength and phenol content obtained by the microwave depolymerization method are much higher than those of other modification methods. KEYWORDS adhesive, degradation, lignin, renewable resources, resins, 1 | INTRODUCTION Since the 1990s, people have begun to advocate 'green chemistry' (Prevention is better than cure). Now the focus is to make use of unavoidable waste. Generally speaking, [...]

In this work, surface‐modified Ce‐Zr oxides and ZnO nanoparticles were conveniently prepared by dopamine (Dpa) treatment and then composited with epoxy (EP) by hot pressing. Thermogravimetric analysis (TGA) and UV‐shielding properties of the EP composites with surface modification with Dpa‐CZ and Dpa‐ZnO were measured. The TGA results showed that the modified treated fillers had no loss of heat resistance of the matrix and had an enhancement effect on the initial and maximum decomposition temperatures. In addition, the UV‐shielding properties of EP composites after Dpa‐CZ and Dpa‐ZnO modifications both showed a significant enhancement effect compared to pure EP. The T(UVA) of the 0.5 wt% Dpa‐ZnO modified composite decreased to less than 0.017%, and the T(UVB) decreased to less than 0.0059%. The T(UVA) of the 0.5 wt% Dpa‐CZ modified composite decreased to less than 15.98%, and the T(UVB) decreased to below 1.14%. The composites have both excellent thermal stability and UV‐shielding efficiency. [ABSTRACT FROM AUTHOR]

Five types of magneto‐rheological elastomers (MREs) based on natural rubber were synthesized by incorporating carbonyl iron particles (CIP) as the primary filler. The objective was to investigate the influence of carbon fiber and magnetic particle content on the mechanical and magneto‐rheological properties of the MREs. Carbon fibers (CF) were further added as secondary reinforcement pre‐modified with polydopamine. The composite's microstructure was examined through scanning electron microscopy (SEM), while the mechanical and magnetodynamic properties were assessed using an electronic universal testing machine and an advanced rotational rheometer. The addition of appropriate amounts of CIP and CF resulted in increased rubber modulus, indicating the formation of a filler‐rubber network and the synergistic effect between carbon fibers as a supporting structure and CIP. Compared to the unfilled MREs, the mechanical and magnetodynamic properties were further improved by adding 2 and 4 wt% CF. These findings demonstrate that employing carbon fibers as reinforcing fillers and incorporating suitable magnetic fillers can enhance the magnetic and mechanical properties of the materials, providing a theoretical basis for the study of MREs' performance. Highlights: CF and CIP synergistically enhance the strength of the rubber matrix.The MR effect is gradually enhanced with the increase of CIP content.Modified CF has a promoting effect on the magnetic responsivity.Magnetic responsivity increases with increasing modified CF content.Improved mechanical and magnetodynamic properties of composites. [ABSTRACT FROM AUTHOR]

Dual-component epoxy resins are widely used for bonding different materials in automotive interior processing. However, due to the complexity and variability of automotive interior parts, uneven temperature distribution on curved surfaces during the thermoforming process can lead to uneven thermal stress distribution, damaging the interior components. This study focuses on addressing the damage issues caused by uneven thermal stress distribution during the thermoforming of automotive interior components. By monitoring the temperature and strain on the adhesive surface of the interior components during processing, using sensors and combining the readings with a finite element simulation, damage to the adhesive during processing was simulated. Based on this, a segmented thermoforming method for the model surface was employed, but it was found that this method did not significantly reduce the level of damage to the adhesive during application. Building upon the segmented simulation, significant results were achieved by applying temperature modulation at a certain frequency to adjust the damage of the interior components during processing. The techniques used in this study successfully reduced the unevenness of the adhesive surface temperature, improved the performance of the adhesive during application through segmented optimization and the application of ultrasound-assisted techniques, and markedly reduced the manufacturing process's energy consumption. [ABSTRACT FROM AUTHOR]

The "weak" friction-induced vibration can help to monitor the change in friction and wear state of friction pairs and detect the failure of surface damage. However, they are typically submerged in complex interference components during friction. Therefore, detecting accurate "weak" friction-induced vibration is key to using it entirely. A method based on the correlation between friction-induced vibration and sound signals was proposed to achieve this goal. The ball–disk wear experiments were conducted under oil lubrication using a wear tester. Vibration and sound pressure signals generated during the experiments were recorded. By the spectrum analysis of the cross-correlation function calculated from the two types of signals, the "weak" FIV components submerged in the original signals were detected. The experimental results showed that the root mean square change of the "weak" friction-induced vibration detected in the vibration and sound pressure signals was highly consistent with the friction coefficient change. It could effectively characterize the transition of the wear stage from running-in to stable wear of the friction pairs. Therefore, the cross-correlation analysis of vibration and sound signals could be a reliable tool for detecting the "weak" friction-induced vibration. [ABSTRACT FROM AUTHOR]