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Actuation in a soft robotic context is often acquired through pneumatics. However the need of pressure tubing for supplying air pressure is a large drawback for small and autonomous soft robots. Using paraffin wax as pressure source is a possible solution to this problem as it has a volume expansion of about 10-15% when it undergoes a phase transition from solid to liquid. In literature several actuators with paraffin have been made but most of them use external heaters for melting the paraffin which are slow due to low thermal conductivity of paraffin. To increase this thermal conductivity as well as to render the paraffin electrically conductive to melt the paraffin through Joule heating, filler elements like graphite have been used. The objective of this thesis is to use carbon nanotubes (CNTs) as filler element as they have promising properties and they have not been used for actuation in this context. A single dot Braille cell actuator, similar to actuators from literature, was built to characterize the performance of the CNT/paraffin mixture. To ensure a good dispersion of CNTs in the paraffin, alternately hot-bath sonication and vortexing was used to create a mixture with 5 weight % of CNTs. Differential scanning calorimetry was used to identify the phase transition. The mixture starts melting at 42 °C and is fully melted at 60 °C. The volume expansion was found to be 15 %. The actuator is based on the dimensions of a dot of a Braille cell and consists of an 1.46 mm thick PCB with a hole of 1.6 mm in diameter. The performance was characterized by deflection of a thin PDS membrane which was put on the PCB after it had been treated with oxygen plasma to ensure a good adhesion. A microscope was used to identify the deflection which resulted in a maximum dot height of 325 μm at a power input of 0.61 W. The time needed to reach the maximum deflection at this power input was about 3 seconds. When compared to other actuators in literature, the single dot Braille cell actuator described in this thesis is the most efficient with respect to the fastest actuation. The actuation time of this actuator is often lower than that of actuators in literature as they use external heaters instead of Joule heating which generates heat inside of the mixture. This thesis also described the deformation of a flexible bending actuator filled with paraffin. A comparison to the same flexible actuators pressurized with air pressure showed that the paraffin generated a pressure of approximately 0.1 MPa when melted. Even though the deformation of the paraffin filled actuator was much smaller than that of the actuator pressurized with air pressure, the deformation proved that paraffin is usable as a possible actuation medium for flexible actuators.