He resulting ENR was coagulated with methanol after which washed with water. Finally, it was dried within a vacuum oven at 50 C before use. two.3. Selectively Etching of HNT by Sulfuric Acid The acid remedy of HNT was conducted as outlined by Zhang et al. . First, a 10 g sample of HNT was added to 100 mL of 3M H2 SO4 remedy. The mixture was heated at 70 C for two, 4, 6, or 8 h. The acid-treated HNT had been then filtered, washed, neutralized for pH, and dried in an oven at 70 C till reaching a continual weight. The acid-treated HNT was ground in a mortar prior to use in compounding. The surface location of acid-treated HNT was then characterized by BET analysis. 2.four. Preparation of ENR/HNT Composites The recipe for the preparation of ENR/HNT composites is offered in Table 1. ENR with 20 mol epoxide (ENR 20) was compounded with 5 phr of HNT (e.g., untreated or acid-treated HNT according to the formulation) plus the other components except for the curatives (CBS and sulfur) within a Brabender plasticorder (Brabender GmbH Co. KG, Duisburg, Germany). The fixed amounts of mol epoxide and HNT have been selected determined by the optimum properties obtained from our prior reports [8,21]. The initial mixing temperature was set at 50 C using a rotor speed of 60 rpm. The compound was then SB-429201 supplier sheeted on a two-roll mill when the curatives were incorporated. Ultimately, samples of your variously treated composites have been tested for curing characteristics.Polymers 2021, 13,four ofTable 1. Formulation of ENR composites filled with untreated and acid-treated HNT. Raw Material ENR 20 Stearic acid Zinc oxide HNT CBS SulfurRemark: HNT was acid-treated with different therapy times.Quantity (phr) 100.0 1.0 5.0 five.0 2.0 2.two.five. Measurement of Curing Qualities The curing properties with the composites were measured in accordance with ASTM D5289 working with a moving die rheometer (Rheoline, Mini MDR Lite, Prescott Instruments Ltd., Tewkesbury, UK). The operating temperature was set at 150 C. The data when it comes to torque, scorch time (ts2 ), and curing time (tc90 ) were recorded because the median values of three repeated tests. The ts2 and tc90 were used in calculating the curing price index (CRI) as N106 medchemexpress follows: CRI = one hundred tc90 – ts2 (1)2.6. Fourier Transform Infrared-Spectroscopic Evaluation (FT-IR) The modifications in functionality of acid-treated HNT and its corresponding composites was confirmed by Fourier transform infrared spectroscopy (FTIR) making use of FTIR spectroscope model TENSOR27 (Bruker Corporation, Billerica, MA, USA). The spectra had been recorded in transmission mode having a four cm-1 resolution over 400050 cm-1 . 2.7. X-ray Diffraction Analysis (XRD) The XRD evaluation of acid-treated HNT and its corresponding composites was carried out working with PHILIPS X’Pert MPD (Eindhoven, Netherlands) with CuK radiation ( = 0.154 nm) at 40 kV and a existing of 30 mA, also as a Bruker D2 Phaser (Billerica, Massachusetts, USA) with CuK radiation supply ( = 0.154 nm) along with a present of ten mA. The diffraction patterns have been scanned for diffraction angles two at 50 having a step size of 0.05 and 3 /min scan speed. The d-spacing of HNT layers in filler particles was estimated utilizing Bragg’s equation. 2.8. Measurement of Mechanical Properties and Hardness Tensile properties were measured as outlined by ASTM D412. The samples were punched with Die C into a dumbbell shape. A universal testing machine (Tinius Olsen, H10KS, Tinius Olsen Ltd., Surrey, UK) was chosen to perform the tensile test at a crosshead speed of 500 mm/min. The determinations.