Effects of heat and moisture on characteristics, tensile properties of RFL‐coated rayon cords, and their adhesion with NR/SBR matrix

Abstract

The objective of this study was to evaluate the effects of heat and moisture on the characteristics and tensile properties of resorcinol-formaldehyde-latex (RFL)-coated rayon cords and their adhesion to the natural rubber (NR)/styrene-butadiene rubber (SBR) matrix. The water absorption ratio, shrinking percentage, breaking force, and elongation at break of the cords, which were treated under various temperature-humidity conditions, were tested, and an attenuated total reflection (ATR)-Fourier transform infrared (FTIR) spectroscopy was used to investigate the chemical changes of the outer RFL layer. The static adhesion was investigated by an H pull-out test, and the evolution of the adhesive properties of the RFL-coated rayon cord/rubber matrix was tracked by an elastomer testing system. A scanning electron microscope (SEM) was employed to observe the interfacial fracture caused by both H pull out and fatigue. The results of this investigation show that the moisture absorption significantly affects the characteristics and the mechanical properties of rayon cords. The chemical state of the RFL layer and the static adhesion of the cord/rubber matrix were not obviously affected, but the interfacial fatigue life was extended due to the decrease of the load in the second of three fatigue stages, which was caused by a reduction in the modulus of the rayon cords.

Cellulose‐Nanofiber‐Reinforced Rubber Composites with Resorcinol Resin Prepared by Elastic Kneading

“…[11] The process to prepare DTRL is shown in Figure 1. When DTRL was used in preparation of rubber composite sheets, they were hydrophilic [12] and had high water contents after soaking in water at 70 °C for 168 h (see Section 2.5). Thus, WDTRL (Figure 1) was prepared as another TEMPO-CNF/resorcinol resin/latex rubbercontaining material.…”

“…Because the DTRL/X-NBR composite sheets contained hydrophilic TEMPO-CNFs, and partly hydrophilic resorcinol resin, 3). latex surfactant molecules, and X-NBR rubber molecules, [12] their water-resistance might have to be taken into account for practical use. The four rubber sheets first conditioned at 23 °C and 50% RH were vacuum dried at 40 °C for 1 d, and then soaked in water at 70 °C for 168 h, [13] followed by vacuum drying to measure the changes in the relative weights based on the first vacuumdried weights (Figure 7a).…”

Factors influencing resorcinol–formaldehyde–latex‐coated continuous basalt fiber cord/rubber interfacial fatigue behavior: Loading direction and RFL formula

“…However, compared to adhesion evaluated in a static mode (H or T pull‐out test, peeling test, and so on), the interfacial fatigue properties are affected by more factors. In our previous work, in addition to the initial adhesive strength, the damage rate, which was influenced by both the interfacial structure and the modulus difference between the cord and the matrix, was also considered as a key factor for the control of the fatigue performance.…”