Figure 1 - available via license: Creative Commons Attribution 3.0 Unported
Content may be subject to copyright.
Source publication
The effects of alkanolamide (ALK) loading and epoxidation on cure characteristics, crosslink density and mechanical properties of unfilled natural rubber (NR) and epoxidized natural rubbers (ENRs) compounds have been investigated. The NR, ENR-25 and ENR-50 having 0, 25 and 50 mol % of epoxidation were utilised. It was found that the cure and scorch...
Similar publications
Crosslinking density and rheometric behaviour of natural rubber (NR)/chloroprene rubber (CR) blends with blend ratios from 0.0 to 100.0% rubber were investigated utilizing the semi efficient vulcanization. The degrees of crosslinking density were calculated using FloryRehner equations. The rheometric properties were tested by utilizing moving die c...
The effect of two grades of epoxidised natural rubbers (ENR 25 and ENR 50), having 25 and 50 mol of epoxidation, on crosslink density and cure characteristics of silica-filled natural rubber (NR) composites were investigated using a semi-efficient vulcanisation system. The ENRs were incorporated separately into the composites at 5.0, 10.0, 15.0, 20...
Using a semi-efficient vulcanization system; a study was carried out on the utilization of alkanolamide as a curative additive in natural rubber (NR) compounds. The alkanolamide was incorporated into the unfilled-NR compound at 0.2, 0.4, 0.6, 0.8, and 1.0 phr. The effect of alkanolamide on rheological and crosslink density properties of the NR comp...
Silica dispersion and silica–natural rubber (NR) interaction are two major issues in determining the performance of a NR/silica composite in tire industry. In our research, the reaction product of 3-isocyanatopropyltrimethoxysilane and a crosslinking agent, poly(tert-butylphenol) disulphide, was used to modify silica. Then, the modified silica was...
A semi EV curing system was applied for studying the effects of nano-sized montmorillonite on rheological and mechanical properties of natural rubber (NR) composites. The montmorillonite as a nano-sized filler which was added into NR at 2.0, 4.0, 6.0, 8.0 and 10.0 parts per hundred rubber (phr). It was found that the montmorillonite functioned as a...
Citations
... However, as temperature proceeded, the active polar groups in the ENR and XNBR structures facilitated the speed of vulcanization of the respective matrices, by acting as curing accelerators [73]. According to Surya et al. [74], the epoxide groups of ENR could activate the adjacent (-C = C-) and cause them more susceptible and ready for curing. The reactivity seems to favor XNBR more due to the reactivity of the additional acrylonitrile content (-C≡N) with the oxygenated groups. ...
The effect of palm oil (PO) on non-polar natural rubber (NR)-carbon black (CB) composites was investigated as a suitable plasticizer. The results were compared with NR-CB-aromatic oil (TDAE), NR-CB-Shea butter oil (SBO) and polar matrices of epoxidized natural rubber (ENR)-CB-PO and carboxylated acrylonitrile-butadiene rubber (XNBR)-CB-PO. The NR—Sx—CB-PO exhibited the best properties, mostly at lower PO content (5 phr). For example, the bound rubber content of PC5 was ⁓7 and ⁓17% higher than SBC5 (NR—Sx—CB—5phr SBO) and TDC5 (NR—Sx—CB—5phr TDAE oil), while PC40 (NR—Sx—CB—40 phr PO) led SB40 (NR—Sx—CB—40 phr SBO) and TDC40 (NR—Sx—CB—40 phr TDAE) by ⁓23 and 83% respectively. The improved dispersion of CB assisted by PO resulted in higher network density indices (∆M/dNm and Nc/molcm−3) and UTS (MPa) for PC5 than PC0 (NR—Sx—CB—0 phr PO), SBC5, TDC5 and XNBRPC5 (XNBR—Sx—CB—5 phr PO) by 3.9, 12.1, 3.4, 6.5, and 1.4% respectively. The PC5 obtained higher EBR (%) than PC0, SBC5, and TDC5 by 199.1, 174.9, and 170.5%, respectively. Therefore, edible PO has demonstrated properties that make it suitable softener capable of substituting petroleum oil plasticizers.
... Epoxidized Natural Rubber (ENR) molecular structure. Reproduced from[155], IOP Publishing Ltd, 2018. ...
Membrane separation processes are prevalent in industrial wastewater treatment because they are more effective than conventional methods at addressing global water issues. Consequently, the ideal membranes with high mechanical strength, thermal characteristics, flux, permeability, porosity, and solute removal capacity must be prepared to aid in the separation process for wastewater treatment. Rubber-based membranes have shown the potential for high mechanical properties in water separation processes to date. In addition, the excellent sustainable practice of natural fibers has attracted great attention from industrial players and researchers for the exploitation of polymer composite membranes to improve the balance between the environment and social and economic concerns. The incorporation of natural fiber in thermoplastic elastomer (TPE) as filler and pore former agent enhances the mechanical properties, and high separation efficiency characteristics of membrane composites are discussed. Furthermore, recent advancements in the fabrication technique of porous membranes affected the membrane’s structure, and the performance of wastewater treatment applications is reviewed.
... Additionally, latex is obtained from the tree that is found in tropical and subtropical regions. Acquire natural rubber, the method of polymerization is employed, which includes isoprene (2-methyl-1,3-butadiene-C 5 H 8 ) n , which can be demonstrated as cis-1,4-polyisoprene ( Fig. 4.1) [7]. In contrast to this, synthetic rubbers are polymers that are termed as elastomers. ...
... The polymerization of natural synthetic rubber[7]. ...
Synthetic rubbers are kind of polymers that comprise of long-chain. Their exceptional physical, chemical, and mechanical make them distinguishable from natural rubber. Their massive applicability can be illustrated from the fact that it has almost surpassed even the usage of natural rubber, and they are a major component of manufacturing tires and the other automobile-related parts and components along with other numerous usages. However, the major difference between both the rubbers is characterized by their origin as the rubber, which is acquired from natural sources, i.e., latex, which is called natural rubber. In contrast with it, the rubber which is synthesized is termed is a synthetic rubber. Moreover, synthetic rubber is manufactured through different methods such as polymerization, compounding, mixing, and latex processing.
... Although natural polyisoprene rubber has a good mechanical characterizations for many useful implementations, it exhibits low resistance towardsthe long environmental attacks [4][5][6]. Wherefore, there are widely possibilities to develop and improve the rubberperformance to obtain new functional propertiessuch as epoxidation and hydroxylation based on the functional group content [7,8]. ...
Attempts for hydroxylation of the synthetic polychloroprene rubber (neoprene) were employed. In this paper, high concentrated aqueous solution
of sodium hydroxide was used to introduce OH groups into liquid polychloroprene rubber via direct hydroxylation process at ambient conditions.
Structure and composition of neoprene rubber before and after the hydroxylation process were investigated by Fourier transform infrared spectroscopy
(FTIR) and X-ray diffraction (XRD)techniques. It is show that there are changes in crystallinity and agglomeration of rubber due to influence of the
strong alkaline medium. Moreover, the morphological observations show that the modified neoprene layers more harder than the unmodified one.
Based on the analytical results and the experimental data, it can develpneoprene rubber for various applications.
Research on the hydrocracking of pyrolysis oil from laboratory glove waste over sulfated Indonesian natural zeolite catalysts as an intelligent effort to treat non-degradable waste has been successfully carried out. Natural zeolite (NZ) was treated with sulfuric acid at 1, 2, and 3 M concentrations, followed by calcination with 20 mL/min of N2 gas to produce SNZ 1, SNZ 2, and SNZ 3 catalysts, respectively. Sulfuric acid treatment of NZ can increase the crystallinity and surface area. Laboratory glove waste was pyrolyzed at 200–300 °C for 2 h to produce oil, which was used as hydrocracking feed. The hydrocracking process was conducted using feed pyrolysis oil at 250 °C with a catalyst-to-feed ratio of 1:100 (wt%) and an H2 gas flow rate of 20 mL/min for 1 h. SNZ catalysts can produce more liquid products than the NZ catalyst and increase the selectivity of the gasoline fraction. As the catalyst with the highest acidity, among other concentration variations, the SNZ 2 catalyst can have 89.41% liquid product and 88.54% gasoline fraction selectivity with good stability for three consecutive runs.
Tuning of the crosslink density (CLD) in the rubber compounds is very crucial for optimizing the physical and mechanical properties of the ultimate rubber products. Conventionally, CLD can be measured via rheological methods such as moving die rheometer (MDR), via mechanical tests such as temperature scanning stress relaxation analysis (TSSR), or via direct swelling experiments using Flory–Rehner approach. In the current study, two novel techniques, focused ion beam - scanning electron microscopy (FIB-SEM) processing, with simultaneous energy dispersive X-ray spectrometry (EDS) mapping analysis and scanning acoustic microscopy (SAM) were combined and correlated to conventional methods on a model recipe of ethylene propylene diene monomer (EPDM) compound having different sulphur contents. Depending on the applied technique, the increase in the crosslink density with sulphur content was found to be 1.7 fold for the Flory–Rehner approach and 1.2 fold for both TSSR and MDR. It is directly monitored from the FIB-SEM-EDS analysis that the sulphur distribution and agglomeration behavior increased in line with ZnO content, which is an indirect indication of the rise in crosslink density. The impedance maps of the crosslinked samples obtained through SAM analysis revealed that the impedance of the samples increased with the increasing sulphur content, which can be attributed to higher level of crosslink density. A quantified correlation was obtained between SAM images and the crosslink density of the samples. It was shown that SAM is a promising tool for practical and non-destructive analysis for determining the formation of crosslink density of the rubbers.
The effects of dodecanol (DDC) incorporations on torque, hardness and morphology behaviors/properties of natural rubber (NR)/precipitated silica (PSi) composites were studied using a typical Semi EV. The NR was loaded with the PSi at a settled dose, thirty phr. The DDC is one type of fatty alcohols that is produced based on the oil of palm kernel. The DDC was incorporated toward the PSi-loaded NR systems/compounds with various doses from one to four 4.0 phr. Because of its roles as a co-curing and internal plasticizer, it was revealed that the DDC affected the torque, hardness and morphology properties of PSi-loaded NR systems. The DDC exhibited the enhancements in torque change and hardness, especially till a three phr of DDC dose. The study on morphology behavior confirmed that the three phr of DDC was the optimum dose in which the cracked surface of PSi-loaded NR system with a three phr of DDC displayed the tremendous line of matrix fracture and surface breaking. Based on the overall results, the DDC incorporations caused the PSi-loaded NR systems in a less hardness but a higher torque change.
This study investigated the influences of stearamide on the tensile modulus and strength of silica-loaded styrene-butadiene rubber (SBR). The SBR was filled with precipitated silica reinforcing filler at a settled dose (thirty phr) and the stearamide was compounded into the silica-filled SBR with range doses from two to eight phr. The influences of stearamide incorporation on the tensile moduli i.e. M300 and M100, tensile strength and also breaking elongation of silica-filled SBR were studied. It was revealed that the stearamide caused pronounced affection in tensile properties of the SBR. The stearamide increased tensile strength and modulus up to a six phr of dose. The improvement in tensile moduli and strength was because of the role of stearamide as the extra plasticizing agent for the silica-filled SBR. The oily property of stearamide improved the silica dispersion and crosslinks level, respectively.
