Coupling Agent Si-69 Research Articles

Communication—Organic Silane Coupling Agent Si-69: A New Organosulfur Cathode Material for Rechargeable Lithium Batteries

An organosulfur compound—organic silane coupling agent, Si-69, was investigated as a novel cathode material for rechargeable lithium batteries. The initial discharge capacity of the Si-69 could reach 298 mAh·g−1 at the current density of 200 mA·g−1, approaching its theoretical capacity (299 mAh·g−1). After 200 cycles, a high reversible capacity of 160 mAh·g−1 still could be obtained. Such a good electrochemical performance, combining with the low-cost feature, makes it a promising cathode material for rechargeable lithium batteries.

Insights into the Reinforcement of Butyl Rubber by Carbon Black and Silica with the Aid of Their Dynamic Properties

ABSTRACTCarbon black (N234) and silica (Vulksail N) with a silane coupling agent Si-69 were chosen as reinforcing fillers in butyl rubber (IIR). The rheological behavior of the IIR compounds and the dynamic mechanical properties of IIR vulcanizates were investigated with a rubber processing analyzer and dynamic mechanical analysis (DMA) to examine the filler dispersion in the rubber matrix and the interaction between filler and matrix. The data indicated that the N234 filled IIR compounds had more filler networks than those filled with silica. Filler networks first appeared at 30 phr N234 and 45 phr silica with silane coupling agent Si-69. The interaction between N234 and IIR was far stronger than that between silica and IIR. However, the silica Vulksail N filled IIR had better wet-grip and lower rolling resistance compared to the carbon black-filled IIR should IIR be chosen as a substitute of styrene-butadiene rubber (SBR) in tire tread. The reinforcing factor, R, R (related to the difference in tan d peak height at Tg for the filled and nonfilled rubbers), also demonstrated that the N234-IIR interaction was stronger than for the silica. IIR with 30 phr N234 exhibited the largest tensile strength, 20.1 MPa, for those vulcanizates examined. The tensile and tear strengths of N234 filled IIR were higher than those of IIR with similar amounts of silica. Thus, it was concluded that N234 is a more active reinforcing filler in IIR than silica (Vulksail N) even with a silane coupling agent (Si-69).

Influence of Coupling Agent Si69 on Properties of Nanocomposites of Nature Rubber with Different Sized Nano-Silica

The effect of coupling agent silane Si69 on properties of nanocomposites of nature rubber with different sized nano-silica (15, 30 and 80 nm)was investigated in terms of curing performance, mechanical properties, Mullins effect, Payne-effect, loss factor, the dynamic heat build-up and dynamic mechanical property etc. while taking the same composites without coupling agent as comparison. Results show that with the addition of the coupling agent Si69, the dispersity of nano-silica in the rubber and the binding of nano-silica with the rubber matrix were improved; the mechanical properties of nano-silica/nature rubber composite were effectively enhanced and the positive sulfuration time t90 was shortened. It is noted that the smaller size of the nano-silica is, the better positive effect on the performance and mechanical properties of the composite can be obtained. Due to the addition of the coupling agent Si69, the Payne-effect, loss factor and the dynamic heat build-up can be reduced for the composites with nano-silica of 15 nm and 30 nm, respectively, but is not obvious for the ones with 80 nm silica.

Effect of the Purple carbon black on the properties of NR/BR blend

Purple black is light colored mineral filler mining in recent years in Hainan. The effect of the dosage of the purple carbon black and purple carbon black modificated by Si69 on the vulcanization characteristics, mechanical properties, thermal stability, the damping performance of NR/BR blend rubber were studied, and the blending adhesive tensile sections were analyzed by SEM. Research showed that, with the increasing dosage of the purple carbon black, vulcanization characteristics of NR/BR blend had a little change. Adding the purple carbon black into blending had a reinforcing effect. when the dosage of the purple carbon black was 20, the mechanical properties of blending adhesive was good; Coupling agent Si69 had a modification effect on the purple carbon black. With increasing dosage of Si69, performance of the rubber was improved initially and then decreased; when the mass fraction of Si69 was 8% of the dosage of the purple carbon black, rubber performance was optimal. Purple carbon black had no obvious effect on thermal stability of the rubber, but it improved the damping rubber temperature and damping factor.

Mechanical, Morphological and Thermally Behaviors of Natural Rubber/Aluminum Powder Composites

Different content of aluminum powder was mixed into natural rubber. Aluminum powder was modified by different coupling agents via wet method, and the modified aluminum filler/NR composite was prepared. The mechanical properties, thermal conductivity and thermogravimetric analysis of the composites was investigated. The results showed that the best physical properties and thermal conductivity of composites were achieved with saline coupling agent Si-69, and Thermo decomposing temperature of 3%TM-38S matching composites improved evidently. SEM test indicated that boundary surface of aluminium fillers and rubber was obviously improved when aluminum powder was modified by coupling agent, which would result in preferable mechanical property. The result of Thermogravimetric analysis showed that after aluminum powder filler was modified by three coupling agents, thermo decomposing temperature and hot lost weight of composites rose obviously. With the increase of Al powder content the thermal conductivity improved greatly, Thermal conductivity of Al/NR composites lay between 0.25 and 0.47 W·m-1·K-1.

The Research on Relationship between Heat Generation and Crosslinking Density of Vulcanized Rubber

Crosslinking density of vulcanized rubber which was filled with carbon black and silica was experimentally researched, and its corresponding heat generation, dynamic lag loss (tanδ) and loss modulus ( E″) were also studied. Based on these tests, the model of the relationship among them was established. The results showed that the characteristic value of crosslinking density Vr almost showed downward trend as a straight line when the quantity of silica increased, but temperature rise, loss modulus E″ and tanδ increased obviously. Silane coupling agent Si-69 could improve the crosslink density and dynamic performance. In the drawing, linear correlation was good in linear fitting between temperature rise and loss modulus, as well as between temperature rise and tanδ. Keywords: vulcanized rubber; crosslingking density; heat generation; hysteresis

The Performance of Barium Sulfate/Nature Rubber Composites Using in Sport Shoes

Modified barium sulfate (MBS) /nature rubber(NR) composite materials were prepared by direct blending methods. Barium sulfate was modified by coupling agent Si-69, titanium esters and stearic acid. Tensile property, hardness and wear resistance of composite materials were studied by various methods. The results showed that the modified barium sulfate fillers had great effect on the reinforcement of the composites.

Comparison of ethylene‐propylene diene terpolymer composites filled with natural and synthesized micas

AbstractIn this paper, EPDM/mica composites were prepared by filling synthesized mica and natural mica separately into ethylene‐propylene diene terpolymer (EPDM) using melt blending technique. Microstructures, electrical properties, gas resistance, and mechanical properties of two EPDM/mica composites were investigated systematically. FTIR show that hydroxyl groups exist on the surface of the micas. These structural hydroxyls could be active sites conducive to the surface modification of mica. XRD analyses reveal that the natural mica is crystalline and the synthesized mica is amorphous. After being modified with silane coupling agent Si69, mica was only exfoliated into smaller micron agglomerates dispersing in EPDM, but the dispersion of amorphous synthesized mica was better. So the EPDM/synthesized mica composite possessed better mechanical property, electrical insulation property, and gas permeability resistance. It is expected that better improvement would be achieved, if mica is exfoliated further into nanosheets dispersing in the rubber matrix. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Preparation and Characterization of Nature Rubber/Attapulgite Composites

In this paper, attapulgite(AT)/nature rubber (NR) composites have been prepared through melt blending process. First, different types of attapulgite were prepared.Secend,Fourier infrared spectroscopic (FTIR) was used to analyze attapulgite.Then,different types of attapulgite were filled into natural rubber according to different proportion.Finally, The mechanisms of composites were analyzed. The results showed that siliane coupling agent Si-69 can improve the dispersion of calcined attapulgite and enhance the chemical interfacial adhesion.

Effect of Silane Coupling Agent on Cure Characteristics and Mechanical Properties of Chloroprene Rubber/Reclaimed Rubber Blend

Chloroprene rubber was blended with whole tire reclaimed rubber (WTR) in presence of different levels of a coupling agent Si69 [bis-(3-(triethoxysilyl)propyl)tetrasulfide] and the cure characteristics and mechanical properties were studied. The rate and state of cure were also affected by the coupling agent. While the cure time was increased, the cure rate and scorch time were decreased with increasing silane content. Tensile strength, tear strength, and abrasion resistance were improved in the presence of coupling agent. Compression set and resilience were adversely affected in presence of silane-coupling agent. Aging studies showed that the blends containing the coupling agent were inferior to the unmodified blends.

Structure and properties of fibrillar silicate/SBR composites by direct blend process

Silicate attapulgite(AT)/Styrene Butadiene rubber (SBR) composites with excellent properties and low cost were first prepared from a direct blending process (including polymer melt blending and emulsion co-coagulation). The structure and properties of above composites were carefully investigated. It was found that most AT separated into dispersed units with diameters less than 100 nm in SBR by the direct blend process. However, a few dispersion units as large as 0.2–0.5 μm and a clear network structure of dispersion units in SBR was observed by TEM, SEM and RPA. AT can be purified, but purified AT cannot be easily dispersed in the rubber matrix by polymer melt blending. Siliane coupling agent Si69 can improve the dispersion of AT and enhance the chemical interfacial adhesion. At the same loading, AT (pretreated with Si69) was found to have better reinforcing effect on SBR than carbon black SRF with particle size 60–100 nm and even than N330 with particle size 26–30 nm to some extent. Meanwhile, the cost of AT/SBR composites is pretty low.