Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – Mixing of two or more solid polymers; mixing of solid...
Patent
1979-02-15
1981-07-14
Briggs, Sr., Wilbert J.
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
Mixing of two or more solid polymers; mixing of solid...
525477, C08G 7742
Patent
active
042787742
ABSTRACT:
Block-copolymers of vinyltrialkylsilane-hexaorganocyclotrisiloxane of the formula: ##STR1## wherein R, R' are the same or different and each R.sub.3 represent methyl, phenyl; R.sub.1, R.sub.2, R.sub.3 --are each an aliphatic radical containing 1 to 4 carbon atoms, Z is a residue of a dilithium initiator of polymerization of a vinyltrialkylsilane K is a residue of a monolithium initiator, which is a hydrocarbon radical- normal or iso-alkyl; K' is hydrogen, an (R.sub.3) Si silcarbonic group wherein R is a C.sub.1 -C.sub.4 alkyl radical, or a hydrocarbon radical; a=0 to 10.sup.4 ; b=0 to 10.sup.4 ; C=10 to 10.sup.4 ; d=10 to 10.sup.4 ; f=0 to 1; g=0 to 1, x.gtoreq.1, with a molecular mass of from 10.sup.3 to 10.sup.6.
A method for preparing these block-copolymers comprises polymerization of vinyltrialkylsilanes in the presence of mono- or dilithiumorganic initiators, whereafter a solution of a hexaorganocyclotrisiloxane is added to the reaction mixture and polymerization is effected to give intermediate block-copolymers, whereafter the polymerization is stopped or the intermediate block-copolymers are combined by means of a cross-linking agent, followed by recovery of the desired product.
The block-copolymers according to the present invention feature a high selectivity of permeation for certain gases. Thus, the ratio of permeability constants for oxygen and nitrogen (P.sub.O.sbsb.2 /P.sub.N.sbsb.2) is as high as 3.5. At the same time, the absolute value of gas-permeability constants is also high, i.e. P.sub.O.sbsb.2 is as high as 1.4.times.10.sup.-8 cm.sup.3.cm/cm.sup.2 cm Hg.sec.
REFERENCES:
patent: 3637899 (1972-01-01), Nametkin et al.
patent: 4080400 (1978-03-01), Martin
Polymer Preprints, vol. 10, No. 2, (1969), C. L. Lee et al., pp. 1361-1366.
Macromolecules, vol. 8, No. 5, (1975), J. G. Zilliox et al., pp. 573-578.
J. Polymer Science, vol. 3A, No. 1, (1965), R. P. Zelinski et al., pp. 93-103.
Carbanions, Living Polymers & Electron Transfer Processes, M. Szwarc, Interscience Publishers, New York, p. 34.
High-molecular Compounds, vol. XA, No. 10, (1968), N. S. Nametkin et al., pp. 2216-2222.
Durgarian Sergei G.
Filippova Valentina G.
Gladkova Natalya K.
Nametkin Nikolai S.
Novitsky Eduard G.
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