Molecular confinement of solid and gaseous phases of self-standing bulk nanoporous polymers inducing enhanced and unexpected physical properties

• DOI: 10.1016/j.polymer.2017.02.046
• Publication Date: 2017-02-15T15:00:53Z
• Authors: Javier Pinto; Belen Notario; Raquel Verdejo; Michel Dumon; Stephane Costeux; Miguel Angel Rodr...
• Keywords: Nanoporous

In this work it is provided the first evidence of the polymer chains confinement within self-standing pore walls of nanoporous materials based on poly (methyl methacrylate) (PMMA). This was made possible by producing a series of porous samples with a wide range of pore sizes between 90 nm and 3 μm using processes combining CO sorption, selective block copolymer swelling or homogeneous physical foaming. Mobility restrictions of the PMMA chains in the porous samples with pore size below 200 nm was consistently demonstrated with several experimental techniques, including differential scanning calorimetry, Raman spectroscopy, and broadband dielectric spectroscopy. In addition, several scale-reduction phenomena related to the constitutive elements of the porous materials, both in the polymeric and gaseous phases, and to the porous architecture are identified. The significance of these phenomena on macroscopic electrical conductivity and permittivity of the nanoporous materials is demonstrated, and the presented observations support previous explanations of improved mechanical properties and thermal insulation of this type of nano-materials.<br/>Peer Reviewed<br/>Financial support from The Dow Chemical Company USA, FPI grant BES-2013-062852 (B. Notario) from the Spanish Ministry of Education, MINECO (MAT 2012-34901), and the Junta of Castile and Leon (VA035U13) is gratefully acknowledged. J. Pinto and B. Notario contributed equally to this work.<br/>Supplementary data related to this chapter can be found at http://dx.doi.org/10.1016/j.polymer.2017.02.046.<br/>