Abstract: Polyol-polycarbonates having a molecular weight comprising within the range from 750 to 2500, endowed with good rheologic characteristics and having a low glass transition temperature (Tg), are obtained by means of the reaction, under transesterification conditions, of(a) an organic carbonate;(b) a saturated alifatic .alpha.,.omega.-glycol; and(c) tris-(hydroxyethyl)-isocyanurate.These polyol-polycarbonates are useful as bases for paints in combination with polyisocyanates.Furthermore, the polyol-polycarbonates can be reacted with bicarboxy acids, or with cyclic anhydrides in order to yield the corresponding products with carboxy end groups which are useful as bases for paints in combination with melaminic or epoxy resins.

Abstract: Isobutene is copolymerized with an unsaturated comonomer containing the chlorosilanic function, and the chlorosilanic function is subsequently transformed into an alkoxysilanic function by means of a reaction of alcoholysis, thus silylated copolymers of isobutene being obtained, which are crosslinkable under ambient conditions, suitable for use in sealants and paints.

Abstract: Fluid compositions capable of crosslinking in ambient humidity to form elastomeric products are disclosed, comprising:(A) an elastomeric aliphatic polycarbonate;(B) an organic compound containing at least two N.dbd.C< groups, selected from bisketimines, bisketiminoenamines and bisketiminosilazanes;(C) a tertiary amine with stress nitrogen bonded to a ketiminic carbon atom, preferably a bicyclic ketimine.

Abstract: An organosiliconic fluid composition, suitable for use in sealants, formed by a liquid phase and by a solid and insoluble polymeric phase, dispersed in said liquid phase, is obtained by polymerizing, under the influence of free-radical initiators, styrene, or a mixture of styrene with at least one other vinyl-containing monomer, the polymerization being carried out in the presence of a liquid polyoxypropylenediol-.alpha.,.omega.-bis-allyl silylate having formula (I): ##STR1## or in the presence of a liquid polycarbonate of polyoxypropylenediol-.alpha.,.omega.-bis-allyl silylate having formula (II): ##STR2## wherein: R is an alkyl radical,X is a hydrolyzable radical selected from alkoxy, aminooxy and acyloxy radicals,y is 0, 1 or 2,p is a number ranging from about 10 to about 100,m and n are numbers such as to give to compounds (I) and (II) a molecular weight value, or an average molecular weight value, of from 2000 to 20,000.

Abstract: Novel polyacetylene films are disclosed, having the following properties:elongation at break (1/10): higher than 4tensile strength: higher than 100 MPaability of attaining under stretch high levels of molecular orientation in the direction of pull.The process for preparing such polyacetylene films is also described.

Abstract: A novel catalytic system is disclosed which is especially adapted for the polymerization and the copolymerization of aliphatic conjugated diolefines, the system comprising an organic compound of aluminum, a Lewis acid containing at least one halogen, and an organic compound of a lanthanide metal. The catalyst system has outstanding and hitherto unparalleled activity. The method of preparation of the catalytic system is also described in detail.

Abstract: A new uranium allyl compound, represented by the formula: ##EQU1## WHEREIN R.sub.1, R.sub.2, R.sub.3, R.sub.4, and R.sub.5, which may be the same or different, are members of the group consisting of H, alkyl radicals containing from 1 to 10 C atoms, aryl radicals containing from 6 to 10 C atoms, cycloalkyl radicals containing from 4 to 10 C atoms, and alkyl aryl radicals containing from 7 to 10 C atoms, the dotted line linking the three carbon atoms indicates possible delocalization of the valence electrons of the double bond, X is an anion selected from Cl.sup.-, Br.sup.- and I.sup.- and n is an integer ranging from 1 to 3. The members of that group of compounds are useful, respectively, as catalysts in the stereospecific polymerization of diolefins and may be prepared by reacting a compound represented by the formula: ##EQU2## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5 and the dotted line have the significance given above, with a compound represented by the formulae HX or X.sub.

Abstract: A process for the stereospecific polymerization of olefins is described, wherein the selected monomer is homopolymerized, or the selected monomers are copolymerized, by reacting the selected monomer or monomers in the presence of a catalyst consisting of an uranium .pi. - allyl compound represented by one of the formulae: ##EQU1## in which R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5, the same or different, may be hydrogen atoms, alkyl radicals having from 1 to 10 carbon atoms, aryl radicals having from 6 to 10 carbon atoms, cycloalkyl radicals having from 4 to 10 carbon atoms, and alkylaryl radicals; the dotted line indicates the possible delocalization of the valence electrons; X is an anion selected from among Cl.sup.-, Br.sup.- and I.sup.-; and n is an integer ranging from 1 to 3; and, optionally, a co-catalyst which is a Lewis acid, or a complex thereof with an ether, a tertiary amine or a phosphine.

Abstract: An olefin or diolefin is polymerized, and mixtures thereof are copolymerized, in the presence of a catalyst system consisting of:A. a uranium compound consisting of U(OCH.sub.3).sub.4, U(OCH.sub.3).sub.3 Cl, U(OC.sub.4 H.sub.9).sub.4, U(OC.sub.8 H.sub.17).sub.4, U [N(C.sub.2 H.sub.5).sub.2 ].sub.4, U [N(C.sub.2 H.sub.5).sub.2 ].sub.3 Br, U(OCH.sub.3).sub.5, U(O-i-C.sub.4 H.sub.9).sub.5 ;b. a reducing compound of a metal belonging to the 2nd or 3rd group of the periodic system, selected from the hydrides, mixed hydrides and alkyl derivatives thereof;C. a Lewis acid selected from AlBr.sub.3, AlI.sub.3, AlCl.sub.3, AlCl.sub.3.OEt.sub.2, Al R Cl.sub.2, B Cl.sub.3 and TiCl.sub.4, wherein R is a hydrocarbon radical.