DE4340902C2 - Use of a rubber compound for the production of rubber springs and rubber couplings - Google Patents

Description

From the document US 38 61 661 rubber compounds are based Natural rubber, styrene-butadiene rubber or butyl rubber for the production of Rubber products known, in particular a vibration damper presented becomes.

From the document DE-PS 12 34 382 is also a method for adherent bonding of rubber to metals, using Rubber mixtures, the epoxidized polymers of conjugated dienes or their Mixtures contain, for example, based on natural rubber and epoxidized Natural rubber.

Finally, from Chemical Abstracts Vol. 112, 1990, page 74, Ref. No. 218503u known, in metal rubber springs in sandwich construction natural rubber, epoxidized Natural rubber or nitrile rubber to use.

The following will now be on the state of the art of rubber springs and Rubber couplings detailed.

Two rubber springs or rubber couplings of the same geometry, dimensions and Shore A hardness, but from rubber compounds of different recipe design, can with only slightly different static properties have significantly different dynamic properties. These Both rubber mixtures or their vulcanizates show a different dynamic stiffening.

From an application point of view, rubber springs and rubber couplings are lower dynamic stiffening advantageous. Such springs and couplings lead - a low static stiffness (eg due to a lower Shore A hardness) assumed - too  Vibration systems with low natural frequencies and so often allow one sufficient or even good vibration isolation even at low or medium Excitation frequencies (operating pressure figures).

Such conditions are often present in marine propulsion systems and require Such rubber springs for the elastic storage of the main engines or such Rubber couplings in the torsional vibration systems.

Dynamic low stiffening rubber springs and rubber couplings lead to low Reaction forces / reaction moments and are also favorable for this reason.

Rubber springs or rubber couplings with high damping reduce the Passing through resonant conditions occurring vibrations considerably and thus cause a reduction in the vibration stress of the machine, the device or the plant. The heating of such springs or couplings is lower than that Heating of springs or couplings with low attenuation, because the heating in is approximately square relationship to the vibration amplitude.

For passive insulation, such springs are also suitable because usually low Systemigenfrequenzen and high losses are required.

For shock insulation are usually soft springs and additional dampers required. If rubber springs are possible, those with low stiffness are suitable. low dynamic stiffening and high damping best.

In the production of a rubber mixture of different elastomer types must their compatibility in the polymer blend are taken into account. Become Requires vulcanizate properties that can not be met by any elastomer alone, so it is important that a thermodynamically compatible polymer blend is ready, the optimally has all the required properties. In addition, such must Be crosslinkable polymer blend.

The object of the invention is to use a rubber mixture based on natural rubber and customary Mischingingredienzien such as fillers, plasticizers, antiaging agents, crosslinking agents, zinc oxide and optionally other additives for the production of rubber springs and rubber couplings with low dynamic stiffening and high damping, now According to the invention, the natural rubber is a blend, consisting of

• - 45 to 70 wt .-% epoxidized natural rubber, in which about 50% of Double bonds are epoxidized; as well as out
• 10 to 25% by weight of viscosity-stabilized natural rubber.

Within the following experimental part are recipes (Table 1) with Test results (Table 2). The mixture variant A represents (Comparative Example) the conventional rubber mixture and the mixture variant B the recipe of the invention is, u. z. in conjunction with a rubber coupling as Embodiment.  

Table 1

Table 2

test results

symbolism

parameter symbol Stress value at 100% elongation σ ₁₀₀ tensile strenght σ _B elongation ε _B vulcanizate H impact resilience e Compression set at constant compression DRV loss factor tanδ ₁ Relative attenuation (ψ = 2π × sinδ, with small ∡ the following applies: sinδ = tanδ) ψ Static spring constant F _stat Dynamic spring constant F _dyn Logarithmic decrement of mechanical damping Λ Angle of rotation for a given torque δ ₂ Dynamic torsional rigidity C _Tdyn

Claims (1)

1. Use of a rubber mixture based on natural rubber and customary mixture ingredients, such as fillers, plasticizers, antiaging agents, crosslinking agents, zinc oxide and optionally other additives, wherein the natural rubber is a blend consisting of

• - 45 to 70 wt .-% epoxidized natural rubber in which about 50% of the double bonds are epoxidized; as well as out
• 10 to 25% by weight of viscosity-stabilized natural rubber;

for the production of rubber springs and rubber couplings.