Polymerization of norbornene bearing Si(
CH
3)
3 groups in the 5-position with the opening of doublebonds and its
copolymerization with 5-(
n-hexyl)norbornene were realized in the presen
ce of ni
ckel(II) naphthenate/methylaluminoxane
catalyst system. The
completely saturated homopolymer
containing Si(CH
3)
3 group (APNSi)and a
copolymer
containing both Si(CH
3)
3 and
n-hexyl side groups (ACPNHSi) were prepared. The polymershave mole
cular mass of about 300 000 and a high glass transition temperature (
Tg > 340
C). Gas permeationproperties of the polymers obtained were studied. APNSi reveals unusually high gas permeation parameters, e.g.,
P(O
2) of about 800 Barrer for different samples. This polymer also exhibits solubility
controlled gas permeation:the permeability
coeffi
cients in
crease in the series of
n-alkanes C
1-C
4 when the size of the penetrant in
creases.Free volume in addition type substituted polynorbornenes was studied using positron annihilation lifetimespe
ctros
copy (PALS). This method indi
cated that very large sizes of free volume elements are
chara
cteristi
c forAPNSi what explains its great gas permeability. Another interesting feature of this polymer is an independen
ceof the annihilation parameters (lifetimes
chars/tau.gif" BORDER=0 >
i and intensities
Ii) of temperature in a wide range of its variation.Thus, APNSi is a novel representative of high free volume, high permeability glassy polymers, and it is a potentialmaterial for gas separation membranes.