Abstract:
Process for the production of polyacetylene, wherein acetylene is polymerized in an organic diluent with the aid of an organometallic mixed catalyst based on a vanadium compound of the formula ##STR1## wherein R.sup.1 represents halogen (chlorine),R.sup.2 and R.sup.3 represent halogen (chlorine), OR.sup.5 (R.sup.5 =C.sub.1 -C.sub.20 alkyl, straight chain, cyclic or branched), wherebyR.sup.2 and R.sup.3 may be the same or different,and on an luminium alkyl compound.
Abstract:
Ethylene-butadiene-isoprene terpolymers consisting of more than 80 mol % of alternating ethylene-diene units and in which more than 95 mol % of the diene units built into the polymer are in the 1,4-configuration.
Abstract:
A catalyst comprising:(a) an organometallic compound corresponding to the following general formula: RMe wherein R represents a saturated aliphatic or aromatic hydrocarbon radical having from 2 to 8 carbon atoms; and Me represents an alkali metal;(b) a compound corresponding to the following general formula: R'OMe' wherein R' represents a saturated aliphatic or aromatic hydrocarbon radical having from 2 to 8 carbon atoms; and Me' represents an alkali metal; and(c) a tertiary aliphatic triamine.A process for the preparation of said catalyst wherein components (a), (b) and (c) are dissolved, in any order, in an aliphatic or aromatic hydrocarbon and reacted at temperatures of from 0.degree. to 100.degree. C., and its use in the preparation of telomeric polybutadiene homo- or co-polymers.
Abstract:
The invention refers to Isoprene-ethylene copolymers having alternating monomer units in which the proportion of recurring-isoprene-ethylene-sequences is more than 80 mol %, in which the proportion of built-in isoprene in the 1,4-configuration is more than 80 mol % which consists of more than 70 mol % of a trans-arrangement, and in which less than 5 mol % of the built-in isoprene is present in the 3,4-configuration, the copolymers having a glass temperature of between -70.degree. C. and -90.degree. C., a Mooney-viscosity of between 30 and 150 [ML 1+4 (100.degree. C.)] and a viscosity number [.eta.], measured at 25.degree. C. in toluene, of between 0.5 and 6, and a process for their preparation characterized in that polymerization is carried out in solution at a temperature of between -80.degree. C. and +100.degree. C. in the presence of a catalyst system which consists of(a) a vanadium compound of the formula VO(OR).sub.2 X and(b) an organoaluminium compound of formula Al R'.sub.3, HAlR'.sub.2 or R'.sub.2 ALY whereinR represents an alkyl group containing from 1-20 carbon atoms,X represents a halogen atom,R'represents an alkyl group containing from 1 to 8 carbon atomsY represents a halogen atom; whereby the molar ratio of b:a is between 100:1 and 1:10.
Abstract:
Graft polymers having improved low temperature characteristics of optionally partially or completely saponified vinyl ester homopolymers or copolymers as graft substrates and grafted siloxane units.
Abstract:
Process for the production of a suspension of polyacetylene in the form of particles having a diameter of from 0.01 to 1 mm and having a great number of fibrous appendices comprising introducing acetylene in an organic suspending agent under constant stirring, in the presence of an aluminum-containing organometallic mixed catalyst in an amount corresponding to 10 to 100 m moles aluminium per liter suspending agent, at temperatures of from -100.degree. to 80.degree. C., until a maximum of 10 g, preferably 1 to 3 g of polyacetylene per liter of suspending agent have been formed.
Abstract:
A catalyst comprising:(a) an organometallic compound corresponding to the following general formula: RMe wherein R represents a saturated aliphatic or aromatic hydrocarbon radical having from 2 to 8 carbon atoms; and Me represents an alkali metal;(b) a compound corresponding to the following general formula: R'OMe' wherein R' represents a saturated aliphatic or aromatic hydrocarbon radical having from 2 to 8 carbon atoms; and Me' represents an alkali metal; and(c) a tertiary aliphatic triamine.A process for the preparation of said catalyst wherein components (a), (b) and (c) are dissolved, in any order, in an aliphatic or aromatic hydrocarbon and reacted at temperatures of from 0.degree. to 100.degree. C., and its use in the preparation of telomeric polybutadiene homo- or co-polymers.
Abstract:
The production of diene rubbers polymerized by means of Nd catalysts and having reduced cold flow and low intrinsic odor is effected by the polymerization of diolefines adiabatically at temperatures of -20.degree. to 150.degree. C. in the presence of inert organic solvents and in the presence of metallo-organic mixed catalysts based on neodymium carboxylate, by subsequently depressurizing the reaction mixture obtained in this manner by reducing the pressure, and by treating the reaction mixture thereafter with disulphur dichloride, sulphur dichloride and/or thionyl chloride.