Microactuators are an essential component in microsystems or microdevices, and in applications that include artificial muscles, pumps, valves, or switchers. Liquid‐crystalline elastomers are a new class of actuator material in the field of microsystem technologies, which can be used in standard processes. This newly developed actuator provides new possibilities in microfluidics because of its dimensional changes activated by the increase in temperature.

Photo‐crosslinkable side‐chain liquid‐crystalline polymers (LCPs) containing photoreactive benzophenone cores are synthesized in order to obtain their corresponding side‐chain liquid‐crystalline elastomers (LCEs). This strategic synthesis allows thin elastomeric films and their integration into microsystems for actuators and micromachines to be obtained. As an example of this principle, a gripper was developed. The position of its arms can be changed by applying voltages from 1.5 to 3.5 V at different rates. Small changes in the liquid‐crystalline elastomer film cause strains of up to 150% in the microdevice and the capacity to move up to 400 times its own mass due to the nematic‐to‐isotropic transformation.magnified image

The silicone elastomers offer in our days new perspective for the construction in the precision engineering and in the medicine because of their special mechanical, electrical, optical and chemical properties. Since the essential material parameters like storage modulus and loss modulus depend on temperature and frequency explicit it is important for simulations to know these characteristics. This report is about determining of relaxation behaviour of silicone rubbers and about finding the mathematical relation to describe time-temperature equivalence of silicone elastomers. As conclusion we can declare that the common used Williams–Landel-Ferry equation to describe temperature and time dependent behaviour of polymers is not applicable for silicone rubbers.

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