Thermo-Mechanical Behavior of Novel Wood Laminae-Thermoplastic Starch Biodegradable Composites With Thermal Energy Storage/Release Capability

Abstract

For the first time, multifunctional fully biodegradable composites combining structural and thermal energy storage/release capabilities were prepared and thermo-mechanically characterized. Within this scope, thin beech laminae impregnated with a phase change material (PCM) represented by poly(ethylene glycol) (PEG) were interleaved with thin foils of thermoplastic starch (TPS) and consolidated by hot pressing. From scanning electron microscopy, it was observed that a certain amount of PEG (about 11 wt% of the total laminate) remained entrapped within the wood pores, negatively affecting the interfacial adhesion between wood laminae and TPS foils. The presence of PEG stabilized in the wood laminae was confirmed by differential scanning calorimetry tests, in which a specific melting enthalpy of 27.4 J/g was detected with a melting peak at 55 • C. Wood permeation with PEG was responsible for an increase of the dynamic moduli E ′ and E ′′ , as well as of the tensile and Charpy impact strength of the laminates. Therefore, this paper highlighted the possibility of developing multifunctional fully biodegradable composites capable of combining structural and thermal energy storage properties, in which the selected PCM positively contributed to the mechanical behavior of the laminates.

Production and Characterization of TES-EPDM Foams With Paraffin for Thermal Management Applications

“…In order to store a large amount of thermal energy, latent heat TES systems are of particular interest: their working principle is the transition of the material from a physical state to another state and for this reason they are called phase change materials (PCMs) (Bo et al, 1999;Peng et al, 2004;Borreguero et al, 2010;Dorigato et al, 2017b). Examples of PCM are paraffin waxes (Pielichowska and Pielichowski, 2014;de Gracia and Cabeza, 2015;Fredi et al, 2017;Galvagnini et al, 2020;Valentini et al, 2021), polyethylenglycol (PEG; Dorigato et al, 2019), and fatty alcohols (Valentini et al, 2020). Paraffins are organic PCMs widely used for the thermoregulation of buildings (Borreguero et al, 2010;Castellon et al, 2010), sportswear (Rigotti et al, 2018), smart fabrics (Fallahi et al, 2010;Salaün et al, 2010;Fredi et al, 2018), due to their low cost, a high heat of fusion, noticeable chemical stability, and a broad range of melting temperatures (Bo et al, 1999(Bo et al, , 2004Peng et al, 2004).…”

Polydopamine-Coated Paraffin Microcapsules as a Multifunctional Filler Enhancing Thermal and Mechanical Performance of a Flexible Epoxy Resin

“…The scientific literature reports many examples of thermoplastic or thermosetting matrices containing microencapsulated or variously stabilized PCMs [4,12,[24][25][26][27][28][29]. Our group has recently developed numerous polymer matrices and reinforced polymer composites that combine good mechanical properties and TES capability-for example, polyamide/glass laminates enhanced with a microencapsulated or a shape-stabilized paraffinic PCM [30][31][32], polyamide-based composites containing discontinuous carbon fibers and paraffin microcapsules [33,34], epoxy/carbon composites containing microencapsulated or shape-stabilized paraffin [35][36][37][38][39][40], laminates based on a reactive thermoplastic resin and paraffin microcapsules [41,42], polypropylene filaments containing a microencapsulated PCM [43], and a biodegradable laminate composed of ultrathin wood laminae, thermoplastic starch, and a poly(ethylene glycol) as the PCM [44].…”

Melt-spun polypropylene filaments containing paraffin microcapsules for multifunctional hybrid yarns and smart thermoregulating thermoplastic composites

“…However, limited research has been carried out so far to produce such structural TES composites. Some examples are reported in the literature of continuous or discontinuous fiber composites with thermosetting [20][21][22][23][24], thermoplastic [25][26][27][28], or reactive thermoplastic [29,30] matrices. However, the research on continuous-fiber composites with a traditional thermoplastic matrix and TES capability is limited to a single work [25], in which the compaction is performed via film stacking.…”