Polyurethane-graphene nanocomposite foams with enhanced thermal insulating properties

Abstract

The improvement of thermal insulating performance of polyurethane rigid foams is a crucial task for their use. In this work, the effect of graphene on these properties has been studied by preparing and testing unfilled, 0.3 and 0.5 wt% graphene-filled polyurethane foams. It was found that graphene is able, at very low content (0.3 wt%), to reduce the radiative contribution of the initial thermal conductivity by both decreasing the cell size and increasing the extinction coefficient. Due to the low graphene contents considered, no concerns about the solid-phase contribution of thermal conductivity arise. Polyurethane-graphene nanocomposite foams showed also slower aging rate with respect to unfilled foams.

Morphology, Mechanical and Thermal Properties of Thermoplastic Polyurethane Containing Reduced Graphene Oxide and Graphene Nanoplatelets

“…The addition of graphene allows for meeting the increasing requirements put in many applications. Besides the improvement of mechanical properties [ 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 ] and thermal stability [ 10 , 16 , 27 , 28 ], the modification of segmented polyurethanes by graphene can improve shape memory effect [ 15 , 21 , 24 , 25 , 29 , 30 , 31 ], gas-barrier properties [ 19 ], and electrical conductivity [ 16 , 18 , 19 , 23 , 32 ]. Graphene-polyurethane nanocomposites can be used as a selective membrane in filtration [ 33 ], piezoelectric sensors [ 34 , 35 ], actuators [ 30 , 36 ], or self-healing materials [ 20 , 37 , 38 ].…”

Sustainable rigid polyurethane foams based on recycled polyols from chemical recycling of waste polyurethane foams

“…Figure shows the thermal conductivity of the RPUFs based on RP‐A and RP‐B. Typically, the thermal conductivity of closed‐cell foams is strongly affected by parameters such as density, cell size, closed‐cell content, and thermal conductivity of the polymer matrix and blowing gas . The thermal conductivity of the RPUFs based on RP‐A or RP‐B was reduced with increasing RP content, exhibiting the minimum value at 80 wt % RP content.…”

Long‐term thermal conductivity of cyclopentane–water blown rigid polyurethane foams reinforced with different types of fillers

“…The use of fillers is of great interest in the field of RPU foams because their addition can improve the thermal insulation of these materials. 10,11,[20][21][22] In this work we report the effect of different types of particles (talc (T), diatomaceous earth (DE) and non-porous silica (NPS)) on the long-term thermal conductivity of RPU foams containing CP and water as blowing agents. In addition, another aim of this work was to establish, for the first time, a correlation between the effect of the fillers during foaming and the aging performance.…”

“…Thermal aging has been studied in previous reports for RPU foams containing different blowing agents, but so far thermal aging of RPU foams reinforced with fillers has not been studied. The use of fillers is of great interest in the field of RPU foams because their addition can improve the thermal insulation of these materials . In this work we report the effect of different types of particles (talc (T), diatomaceous earth (DE) and non‐porous silica (NPS)) on the long‐term thermal conductivity of RPU foams containing CP and water as blowing agents.…”