3D Printable, Recyclable and Adjustable Comb/Bottlebrush Phase Change Polysiloxane Networks toward Sustainable Thermal Energy Storage

Polymeric solid-solid phase change materials (SSPCMs) have garnered enduring attention due to the excellent latent heat and no encapsulation. However, the green manufacturing and recycling use of polymeric SSPCMs have long-term constraint on the development toward sustainable thermal energy storage. Moreover, 3D printing can help polymeric SSPCMs overcome shape limitations and optimize architectures, resulting in the customer-designed objects and effective thermal management. Herein, we proposed a novel strategy to facilely prepare the 3D printable, recyclable and adjustable comb/bottlebrush phase-change polysiloxane networks (Si-ODT-x). Wherein, the grafting crystalline alkyl chain content can effectively regulate the latent heat (from 24.9 J/g to 125.3 J/g), phase-change temperature (from 24.9°C to 53.6°C), thermomechanical and viscoelastic properties of networks. Besides, the degradation and recycling mechanisms were clarified. Moreover, Si-ODT-100 was exemplarily manufactured as a prototype with shape memory ability via 3D printing. Furthermore, the wearable, recyclable and multi-responsive phase-change composite was fabricated by Si-ODT-25 and carbon fiber cloth, which is suitable for the temperature management of human body. This study skillfully combines the tailorable phase-change ability of comb/bottlebrush networks, recyclability of polysiloxane as well as effective photo-induced thiol-ene click reaction, which will open up infinite possibilities for the thermal energy storage materials.