Shape Memory Polymer Foam for Autonomous Climate-Adaptive Building Envelopes

Abstract

Reducing the continuously growing cooling energy demand of buildings is an important part of achieving global emission targets. Here, we present an innovative scenario of how the integration of a programmable material into a climate-adaptive building envelope (CABE) can create an energy-efficient thermal management system inherent to the material. This novel concept is based on a thermoresponsive shape memory polymer foam (SMP) and is designed to regulate the flow of ambient air through the building envelope in order to enable natural cooling of the structure. Hygrothermal simulation data obtained by the software WUFI® Plus indicate that significant cooling energy saving potential may be accessible with this type of concept. As a possible material basis for a corresponding adaptive element, a reactive foamed polyurethane-based SMP foam is proposed, which is capable of executing a thermoreversible shape change of more than 20% while having a suitable switching temperature range. Finally, the ecological impact of such a functional foam element is evaluated in detail as well as its influence on the overall balance of a façade construction by means of a life cycle assessment (LCA).

Design on thermal-mechanism coordination for binding reinforcing mesh based on shape memory polymer

“…However, building structures (such as binding reinforcing mesh) usually require SMP to have a large load capacity, which lead to few applications in the construction field and need further dig deeper. Recently, Yoon developed a building skin that responds to temperature based on thermal-SMP materials [33], and Walter et al designed a climate-adaptive building envelope that helps improve energy efficiency [34]. Based on thermaldriven thermosetting SMP, Yang et al proposed a rebar fixture to achieve binding rebar through utilizing the variable stiffness and shape memory abilities, but the thermosetting SMP cannot be quickly and mass-produced by injection molding equipment [8].…”

Systematic copolymer screening for foaming experiments supported by computational methods

“…1 This type of material features different advantages like relatively high stability, 1 high insulation properties in terms of temperature 2,3 as well as sound, 4 and low density and, thus, minimized material consumption per volume. 2 Therefore, foams are predestinated for different applications such as the automotive industry, 5,6 the construction sector, 7,8 in terms of packaging materials, 9,10 or in shoes. 11 Due to its wide variety of applications, the development of foams with tailored properties is of great importance.…”