Heat-induced bubble expansion as a route to increase the porosity of foam-templated bio-based macroporous polymers

POLYMER

卷:118

Article

Song, Wenzhe¹  Barber, Kevin²  Lee, Koon-Yang¹ 

[1] Imperial Coll London, Dept Aeronaut, Composites Ctr, South Kensington Campus, London SW7 2AZ, England

[2] Thermo Fisher Sci, Hemel Hempstead HP2 7GE, England

关键词: Macroporous polymer;    Mechanical frothing;    Compression properties;   

DOI  :  10.1016/j.polymer.2017.04.058

来源: Elsevier

【 摘 要 】

Macroporous polymers were prepared by mechanically frothing a bio-based epoxy resin and hardener mixture to first create air-in-resin liquid foams, followed by curing of these liquid foams. It was found that heating the air-in-resin liquid foams prior to their gelation decreased the viscosity of the resin mixture and increased the pressure of the air bubbles, leading to an isotropic expansion of the air bubbles. This resulted in an increase in the porosity of the resulting foam-templated macroporous polymers from 71% to 85%. Correspondingly, the compressive moduli (E) and strengths (a) of the foam-templated macroporous polymers decreased from 231 MPa and 5.9 MPa, respectively, to 58 MPa and 1.9 MPa, respectively. This decrease is attributed to an increase in the porosity and pore throat frequency of the foam-templated macroporous polymers when heat was applied to the liquid foams. The deformation of the pores based on in situ SEM micro-compression test of the fabricated foam-templated macroporous polymers is also discussed. (C) 2017 Elsevier Ltd. All rights reserved.

【 授权许可】

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