Nanocomposites and nanomaterials 

The porosity and structure peculiarities of the nanocomposites based on polyurethane/poly(hydroxypropyl methacrylate) matrix and 1,2-propandiolisobutyl-POSS

Karabanova L.V.1, Honcharova L.A.1, Klymchuk D.O.2

1 Institute of Macromolecular Chemistry of NAS of Ukraine, 48 Kharkivske shose, Kyiv 02160, Ukraine, E-mail: lyudmyla_karaban@ukr.net
2N.G.Kholodny Institute of Botany of NAS of Ukraine, 2 Tereshchenkivs’ka str.,Kyiv, 01601,Ukraine
     The nanocomposites based on crosslinked polyurethane (PU), linear poly(hydroxypropyl methacrylate) (PHPMA) contained 1,2-propandiolisobutyl-POSS (1-10 wt%) were created  and the porosity and morphology of the systems have been investigated. As matrix semi-IPN15, semi-IPN30 (PU/PHPMA=85/15 or 70/30) were used.

a

b

Fig. 1a- Isotherms of methanol vapour adsorption by semi-IPN-30 nanocom-posites with different POSS content: 0 (1), 1 (2), 3 (3), 5 (4) and 10 (5) wt. %
Fig. 1b - SEM cross-sectional image of semi-IPN-30 nanocomposite with POSS content 10%  (at magnification 15000 times)	
      The adsorption of methanol vapour by the nanocomposites was investigated using vacuum installation with MacBen balance (Fig 1a).The porosity, specific surface and average dimension of pores were calculated. The introduction of POSS nanoparticles into semi-IPN30 matrix with amount of 5-10% lead to decreasing of specific surface and also to decreasing of total volume of pores. The average dimension of nanocomposite’s pores were in the range of 50-60 Å.
       The morphology was investigated by SEM. The introduction of 1-3% of POSS  into the  matrix semi-IPN-30 results in formation of the nanodomains with size of 50-100 nm. Increasing amount of POSS up to 5-10% lead to formation of microdomains of 1 m and  2-3 m (Fig.1b). The materials with pores of 50-60 Å size are formed and such materials are perspective as gas separating membrane.