Value of the Data •TGA was used as a tool to observe the thermal behaviour and to identify different components of the composite hydrogels, as such or reinforced with different inorganic fillers, and investigate any physicochemical interaction between the composite components. •The impact of the three different clays on the swelling behaviour of the hydrogels was clarified by the water uptake data and may be easily replicated for different synthetic or natural hydrogels. •Safranin-O and Alcian blue are specific stainings for cartilage-like matrix due to their exclusive affinity for glycosaminoglycans, the major component of cartilage. These data could be compared with other chondrogenic differentiation experiments. •The stress-strain curves obtained during static compression tests helped understanding the viscoelastic behaviour of the specimens and could help for any type of soft composites mechanical analysis. •The combination of these data will be helpful for the research community that develops and characterizes composite materials useful in biomaterial field.