scholarly journals Xanthate-modified nanoTiO2 as a novel vulcanization accelerator enhancing mechanical and antibacterial properties of natural rubber

2021 ◽  
Vol 10 (1) ◽  
pp. 478-487
Author(s):  
Yu Liu ◽  
Heliang Wang ◽  
Xiwei Guo ◽  
Mingyuan Yi ◽  
Lihong Wan ◽  
...  

Abstract With the emerging of sustainability, the fabrication of effective and eco-friendly agents for rubber industry has attracted extensive attention. In this study, a novel and nontoxic titanium dioxide-based vulcanization accelerator (xanthate-modified nanotitanium dioxide (TDSX)) with excellent antibacterial performance, for the first time, was synthesized under the catalyst of ceric ammonium nitrate. Notably, the thermal stability of xanthate was greatly enhanced after being grafted on titanium dioxide (TiO2) nanoparticles, in which the activation energy was increased from 6.4 to 92.5 kJ/mol, enabling the obtained TDSX with multiple functions, mainly consisting of fabulous vulcanization-promoting effects, reinforcing effects, antibacterial properties, and anti-ultraviolet aging effects for natural rubber (NR). Simultaneously, the TDSX can be effectively and uniformly dispersed in the rubber matrix along with the developed interface interaction between TDSX particles and rubber matrix. Compared to the traditional accelerators 2-mercaptobenzothiazole (M) system, the tensile strength and the tearing strength of NR/TDSX was improved by 26.3 and 40.4%, respectively. Potentially, our work for preparing green vulcanization accelerator can provide a new design strategy for multifunctional high performance elastomer materials.

2017 ◽  
Vol 751 ◽  
pp. 270-276 ◽  
Author(s):  
Warot Prasanseang ◽  
Chaval Sriwong ◽  
Kittisak Choojun

Ag-natural rubber (Ag-NR) hybrid sheets were successfully prepared with a very simple and low cost method. In this method, silver nanoparticles (AgNPs) were firstly synthesized by a rapid and green microwave-assisted using polyvinylpyrroridone (PVP) media. The effect of PVP weight ratios towards the size of AgNPs was also investigated. Then, Ag-NR hybrid sheet samples were prepared by latex mixing-casting method using concentrated natural rubber (NR) latex with the synthesized AgNPs colloids. The characteristic absorption, particles sizes and shapes of the obtained AgNPs were examined through UV-vis, TEM and SAED. Also, the prepared Ag-NR sheet samples were characterized using XRD, FT-IR, SEM and EDS techniques. It was found that the particles sizes of all the synthesized AgNPs had spherical-like shape, and the mean sizes were increased from 29.7 to 90.4 nm upon increasing PVP contents. EDS results showed the AgNPs were well-dispersed and impregnated into the rubber matrix. Moreover, the antibacterial properties of the prepared Ag-NR sheets were tested by agar disk-diffusion method with Gram-positive and Gram-negative bacteria as Staphylococcus aureus(S. aureus) and Escherichia coli(E. coli), respectively. The results showed that the hybrid sheets exhibited excellent antibacterial properties against these bacteria, in which the zones of inhibition were also dependent on the synthesized AgNPs by utilizing the different amounts of PVP.


2016 ◽  
Vol 72 (7) ◽  
pp. 160-165 ◽  
Author(s):  
Treethip Phakkeeree ◽  
Yuko Ikeda ◽  
Hiroyuki Yokohama ◽  
Pranee Phinyocheep ◽  
Ritsuko Kitano ◽  
...  

2020 ◽  
pp. 073168442097519
Author(s):  
Paveena Tangudom ◽  
Ignacio Martín-Fabiani ◽  
Benjaphorn Prapagdee ◽  
Ekachai Wimolmala ◽  
Teerasak Markpin ◽  
...  

The mechanical and antibacterial properties of acrylic rubber/poly(methyl methacrylate) (AR/PMMA) blend at 10 to 50 wt% of AR content with non-treated and treated titanium dioxide (TiO2) and 2-Hydroxypropyl-3-piperazinyl-quinoline carboxylic acid methacrylate (HPQM) by N-2(aminoethyl)-3-aminopropyl trimethoxysilane were studied. The antibacterial property against Escherichia coli was evaluated. The results found that the mechanical properties of ARt-TiO2/PMMA and ARt-HPQM/PMMA blend were higher than that of the ARTiO2/PMMA and ARHPQM/PMMA blend. For antibacterial property, the ARHPQM/PMMA and ARt-HPQM/PMMA blend could act as the antibacterial material, while the ARTiO2/PMMA blend did not show. However, the ARt-TiO2/PMMA blend could inhibit bacterial cell growth with 10 to 30 wt% of AR content. The recommended compositions of ARt-TiO2/PMMA blend, which improved both mechanical and antibacterial properties, were 10 to 30 wt% of AR and were 10 to 50 wt% of AR for ARt-HPQM/PMMA. Moreover, the UV radiation increased the antibacterial properties by the destruction of the interaction in treated TiO2 and HPQM and improved the antibacterial performance of ARt-TiO2/PMMA and ARt-HPQM/PMMA blend.


2014 ◽  
Vol 2 (39) ◽  
pp. 16531-16537 ◽  
Author(s):  
Yaoming Xiao ◽  
Gaoyi Han ◽  
Yanping Li ◽  
Miaoyu Li ◽  
Yunzhen Chang ◽  
...  

A high performance Perovskite-sensitized nanoporous TiO2photoanode is prepared for the first time by anin situtechnique for use in perovskite solar cells; potentially improving their efficency.


Polymers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1763 ◽  
Author(s):  
Miaomiao Qian ◽  
Weimin Huang ◽  
Jinfeng Wang ◽  
Xiaofeng Wang ◽  
Weiping Liu ◽  
...  

For the first time, phenolic formaldehyde resin (PF)-treated silica carbon black (SiCB) were prepared with different treatment conditions and their effect as fillers on the mechanical properties of filler filled natural rubber/butadiene rubber (NR/BR) composites were investigated in detail. The PF coating layer on the SiCB derived from rusk husk not only promoted the dispersion of the fillers but also improved the interfacial interactions between fillers and the rubber matrix. As a result, both the cross-link density and mechanical properties of the obtained composites were effectively enhanced. The filler SiCB with 3 wt % PF surface treatment greatly improved the tensile strength of NR/BR composites and reached 7.1 MPa, which increased by 73.7% compared with that of SiCB-filled NR/BR composites. The improved interfacial interactions promoted higher energy dissipation, leading to simultaneously enhancing the glass transition temperature of the obtained composites. Due to the easy processing and low cost of filler as well as the effectively enhanced mechanical properties of composites, the PF-coating methodology has a great potential for practical applications in SiCB reinforced high-performance composites. A commercial filler, carbon black (N774), was also used in this study and evaluated under the same conditions for comparison.


2021 ◽  
Vol 41 (5) ◽  
pp. 404-412
Author(s):  
Zong Shen ◽  
Weihua Song ◽  
Xiaolong Li ◽  
Le Yang ◽  
Chaoyu Wang ◽  
...  

Abstract High-performance rubber composites can be obtained by combining the strength of fiber with the high elasticity of rubber. In this article, environmentally friendly natural rubber (NR)/carbon (CB) composites reinforced by maleic anhydride (MAH) grafted hemp fiber (HF) in the presence of polyhydric hyper-branched polyester (PHP) were studied. The grafting of MAH on the surface of HF (HF-MAH) improves the roughness of fibers, the introduced C=C participates in rubber covulcanization with NR matrix at high temperature, thus enhancing the physical locking and chemical crosslinking between HF and NR matrix. The bridge effect was produced between HF-MAH and rubber matrix by PHP, and the interfacial adhesion was further enhanced. As a result, the tensile strength, tear strength, and elongation at break were improved by approximately 14.5, 26.2, and 10.8%, respectively. The 100 and 300% constant elongation stress was increased by 134 and 113%, and the cutting resistance was also improved obviously.


2019 ◽  
Author(s):  
Kent Griffith ◽  
Clare Grey

Nb18W8O69 (9Nb2O5×8WO3) is the tungsten-rich end-member of the Wadsley–Roth crystallographic shear (cs) structures within the Nb2O5–WO3 series. It has the largest block size of any known, stable Wadsley–Roth phase, comprising 5 ´ 5 units of corner-shared MO6 octahedra between the shear planes, giving rise to 2 nm ´ 2 nm blocks. Rapid lithium intercalation is observed in this new candidate battery material and 7Li pulsed field gradient nuclear magnetic resonance spectroscopy – measured in a battery electrode for the first time at room temperature – reveals superionic lithium conductivity. In addition to its promising rate capability, Nb18W8O69 adds a piece to the larger picture of our understanding of high-performance Wadsley–Roth complex metal oxides.


2020 ◽  
Vol 35 (2) ◽  
pp. 146-157
Author(s):  
B.-L. Yu ◽  
L.-C. Jiang ◽  
K. Huang ◽  
X.-L. Liu ◽  
X.-M. Shao ◽  
...  

2019 ◽  
Vol 15 (6) ◽  
pp. 568-573
Author(s):  
Soheil Sedaghat ◽  
Ommoleila Molavi ◽  
Akram Faridi ◽  
Ali Shayanfar ◽  
Mohammad Reza Rashidi

Background: Signal transducer and activator of transcription 3 (STAT3), an oncogenic protein found constitutively active in many types of human malignancies, is considered to be a promising target for cancer therapy. Objective: In this study for the first time, a simple and accurate method has been developed for the determination of a STAT3 dimerization inhibitor called stattic in aqueous and plasma samples. Methods: A reverse-phase high-performance liquid chromatography (RP-HPLC) composed of C18 column as stationary phase, and the mixture of acetonitrile (60%) and water (40%) as mobile phase with a UV detection at 215 nm were applied for quantification of stattic. The developed method was validated by Food and Drug Administration (FDA) guideline. Results: The method provided a linear range between 1-40 and 2.5-40 µg mL-1 for aqueous and plasma samples, respectively, with a correlation coefficient of 0.999. The accuracy (as recovery) of the developed method was found to be between 95-105% for aqueous medium and 85-115% for plasma samples. The precision (as relative standard deviation) for aqueous and plasma samples was less than 6% and 15%, respectively. The sensitivity of the developed method based on FDA guideline was 1 µg mL-1 for aqueous and 2.5 µg mL-1 for plasma samples. Conclusion: These results show that the established method is a fast and accurate quantification for stattic in aqueous and plasma samples.


2012 ◽  
Vol 85 (1) ◽  
pp. 120-131 ◽  
Author(s):  
Md. Najib Alam ◽  
Swapan Kumar Mandal ◽  
Subhas Chandra Debnath

Abstract Several zinc dithiocarbamates (ZDCs) as accelerator derived from safe amine has been exclusively studied in the presence of thiazole-based accelerators to introduce safe dithiocarbamate in the vulcanization of natural rubber. Comparison has been made between conventional unsafe zinc dimethyldithiocarbamate (ZDMC) with safe novel ZDC combined with thizole-based accelerators in the light of mechanical properties. The study reveals that thiuram disulfide and 2-mercaptobenzothiazole (MBT) are always formed from the reaction either between ZDC and dibenzothiazyledisulfide (MBTS) or between ZDC and N-cyclohexyl-2-benzothiazole sulfenamide (CBS). It has been conclusively proved that MBT generated from MBTS or CBS reacts with ZDC and produces tetramethylthiuram disulfide. The observed synergistic activity has been discussed based on the cure and physical data and explained through the results based on high-performance liquid chromatography and a reaction mechanism. Synergistic activity is observed in all binary systems studied. The highest tensile strength is observed in the zinc (N-benzyl piperazino) dithiocarbamate-accelerated system at 3:6 mM ratios. In respect of tensile strength and modulus value, unsafe ZDMC can be successfully replaced by safe ZDCs in combination with thiazole group containing accelerator.


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