Reduce rolling resistance

Because of demands for improved fuel consumption through reduced rolling resistance, a new series of carbon blacks referred to as LH, ie, N300 with this innovation would be N300 LH. Basically this series of blacks has a wider size range in both the primary particles and primary aggregates in addition to a more chemically active surface area. 

Natural mbber was also used extensively in its oil-extended form in winter tires in the 1970s (57). Use of oil-extended natural mbber treads, found to have excellent traction on ice and snow, superseded studded synthetic mbber treads when studs were banned in certain countries and states owing to the damage they cause to partially cleared roads. This concept has been extended into aH-season tires, which account for over 75% of original equipment and replacement tires in the United States. It has been shown (58) that part replacement of styrene—butadiene mbber (SBR) in the formulation of aH-season tire tread compounds with oil-extended natural mbber increases ice and snow traction, reduces rolling resistance, and has no effect on normal wet grip. Also, there is only a minor trade-off in wear performance, because below a tire surface temperature of approximately 32°C, the wear of natural mbber is superior to SBR, whereas above this temperature the reverse is tme (59). Thus, wear of an aH-season tire ultimately depends on the surface temperature of the tread over its annual cycle of temperatures. 

Advances in materials science have been a leading factor contributing to improvements in vehicle fuel economy and performance since the 1973 oil embargo. Better tire materials have reduced rolling resistance, better materials for moving parts have reduced friction, and most importantly lighter body parts have reduced the overall weight of vehicles. 

Yokohama Tire Corporation has combined citrus oil with NR to form super nanopower rubber (SNR) which is being used to reduce the use of petroleum products in the tire by 80%, [34]. Tires containing SNR are lighter than conventional equivalents, reduce rolling resistance by 18%, and are expected to hit the Japanese market later in 2007. 

Introduction by Michelin et Cie. of the "Green Tyre", with a silica-reinforced tread, rather than with carbon black, and using solution-polymerised rather than emulsion-polymerised SBR, for 30% reduced rolling resistance and corresponding energy saving... 

Carbon blacks, silicas and silanes from Degussa s Coatings Advanced Fillers Division are used in tires to reduce rolling resistance, which reduces the fuel con-... 

For the loss tangent properties, the magnitudes of tan 5 for both CB and SSF composites are similar. The magnitude of tan 5 has practical importance in rubber applications such as tires. A rubber composite that has a smaller tan 5 value tends to have a reduced rolling resistance and save energy, while a larger tan 6 tends to have an improved skid resistance and wet grip. The ability of SSF to absorb some moisture in a wet state tends to reduce G , increase tan 5, and lead to better wet traction. 

The palm oil-based alkyds could be used as tackifiers to replace polyterpene and petroleum resin in ENR mbber compound. They could provide better tack strength, impart better road gripping and reduce rolling resistance in tread rabbet However, they should be apphed at low level to avoid reducing the abrasive resistance of the rabbet... 

Silane-modified silicas are used in tire tread compoimds to reduce rolling resistance, increase wear resistance, and improve wet and snow traction properties. 

From a viscoelastic point of view, a high-performance tire should have a low tan 8 value at 50 to 80°C to reduce rolling resistance and save energy. The ideal material should also possess high hysteresis from -20 to 0°C, for high skid resistance and wet grip. 

As stated previously, precipitated silica is being used to replace the carbon black filler in so-called green tyres where it has been shown to reduce rolling resistance [43-46], and so help to reduce fuel consumption. Since the late 1960s, silica has been used in combination with resin systems and at that time PPG introduced a system that consisted of HI-SIL hydrated silica, resorcinol and hexamethylene tetramine (HRH). Initially it was used chiefly for bonding various rubbers to textiles, but such systems have found increasing use in wire coat and belt compounds. 

DPG is the most commonly used member of the guanidine class of rubber accelerators. DPG is commonly used as a secondary accelerator (or kicker ) with primary sulfenamide accelerators and sometimes with thiazole accelerators as well. DPG is also a silanization accelerator. It can interact with the silica surface, which then reacts with organosilanes in tread stocks to help reduce rolling resistance. DPG is not as chemically active as the thiuram or dithiocarbamate accelerators. 

An examination is made of the antioxidant and antiozonant effects of Q-Flex QDI, a quinone diimine produced by Flexsys, in sulphur vulcanised unsaturated rubbers. It is also shown that this additive acts as a scorch retarder and viscosity modifier in NR compounds, and that it modifies the viscoelastic properties of NR compounds resulting in reduced rolling resistance of tyre treads. 5 refs. 

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