Abstract: Apparatus for concentrating and dehydrating maleic acid to form maleic anhydride, comprising: at least a first and a second vertical, independent and distinct, falling thin-film, multitubular evaporators of the static type arranged in series, wherein the first thin-film multitubular evaporator of the static type has an upper part and a lower part and includes a feedpipe at the upper part and a discharge pipe at the lower part; a separator connected by its sidewall to the discharge pipe from the first evaporator and including a first discharge pipe at the upper portion thereof and a second discharge pipe at the lower part; the second thin-film multitubular evaporator of the static type having a feedpipe having an upper part and a lower part connected to the second discharge pipe from the separator and including a discharge pipe only at the lower part thereof; a boiler having an upper part and a lower part, said upper part of said boiler being connected to and in open communication with the lower portion of the

Abstract: A crosslinking process wherein at a temperature of about 10.degree. to 160.degree. C., under a pressure of about 1 to 300 bars and for at least about 0.5 hour, a polymer, containing from about 42 to 99% by weight of units derived from ethylene and, where appropriate, also from an .alpha.-olefin, from about 1 to 8% by weight of units derived from maleic anhydride and from 0 to about 50% by weight of units derived from at least one additional monomer selected from an ester of an unsaturated carboxylic acid with an alcohol containing from 1 to 12 carbon atoms, is reacted with at least one polyepoxide compound, preferably present in an amount of from about 1 to 10 parts by weight, based on 100 parts by weight of the polymer, in the presence of at least one catalyst suitable for reacting the anhydride functions with the epoxide functions. The catalyst is preferably present in an amount from about 0.02 to 2 parts by weight, based on 100 parts by weight of the polymer.

Abstract: The present invention provides a bitumen-polymer composition comprising 95 to 99% by weight of a bitumen and 1 to 5% by weight of a terpolymer having a melt index between 5 and 50 dg/min. The terpolymer comprises 88 to 98.7 mol % of units derived from ethylene; 1 to 10 mol % of units derived from at least one ester selected from the group consisting of alkyl acrylates and methacrylates, the alkyl group having from 1 to 6 carbon atoms; and 0.3 to 3 mol % of units derived from maleic anhydride. The bitumen-polymer composition is used in the preparation of road surface binders.

Abstract: A process for the manufacture of radical ethylene terpolymers or copolymers comprising moieties derived from an alkyl (meth)acrylate and/or moieties derived from maleic anhydride by copolymerizing, in the presence of at least one free-radical initiator, a mixture of ethylene, (meth)acrylate and/or maleic anhydride in a device comprising a primary compressor, the delivery pressure of which is between 200 and 300 bars, connected to a secondary compressor which is connected directly to a polymerization reactor, fresh ethylene being fed at the intake of the said primary compressor and said copolymerization being carried out in the said polymerization reactor under a pressure of between 1,000 and 2,500 bars and at a temperature of between 140.degree. and 280.degree. C., wherein the feeding of the (meth)acrylate and/or maleic anhydride into the reactor if effected by introducing maleic anhydride and/or (meth)acrylate at the intake of the secondary compressor.

Abstract: An apparatus for evacuating the gases resulting from the decomposition of industrial process gases, such as ethylene, contained in a vessel under high pressure is adjacent to the vessel. The apparatus comprises:(1) at least one safety means separating the apparatus from the vessel;(2) a reservoir with a volume which is 2 to 100 times that of the vessel;(3) at least one connecting pipe between the vessel and the reservoir; and(4) at least one chimney between the reservoir and the atmosphere.The apparatus is useful for the recovery of decomposition gases for the purpose of preventing atmospheric pollution. The risk of explosion is reduced by evacuating decomposition gases through the apparatus.

Abstract: Apparatus for cooling plastic film or sheet obtained by blowing tubing, comprising at its intermediate section an intensive blowing ring for directing air towards the tubing and at its upper section an upper chamber in which the tubing is in contact with an air flow directed in the drawing direction of the tubing. At the lower section of the apparatus is a non-closed lower chamber provided with at least one opening. The apparatus can be used to form blown films having superior optical properties, particularly clarity and turbidity, from a large number of resins.

Abstract: A cold-stretchable, self-adhesive film composition comprising (a) from 88 to 97% by weight of an ethylene-.alpha.-olefin copolymer, the .alpha.-olefin having from 3 to 10 carbon atoms and the copolymer having a density of between 0.905 and 0.940 g/cm.sup.3 and a melt index of between 0.1 and 2 dg/minutes and; (b) from 3 to 12% by weight of a polymer selected from among polyisobutylene, atactic polypropylene, cis-polybutadiene and bromobutyl rubber. The film compositions find particular use in the automation of the spiral wrap-round packaging technique.

Abstract: A composition comprising from 25 to 95 weight percent of at least one free-radical ethylene polymer and from 5 to 75 weight percent of at least one ethylene .alpha.-olefin copolymer, wherein the .alpha.-olefin contains at least 4 carbon atoms, wherein the copolymer has a specific gravity between 0.905 and 0.940 and a melt index between 0.4 and 3 dg/min, and wherein the free-radical ethylene polymer has a melt index between 0.15 and 3 dg/min. Application to the manufacture of films having a thickness between 8 and 200 microns and other applications.

Abstract: A composition comprising from 2 to 25 weight percent of at least one free radical ethylene polymer with a specific gravity between 0.91 and 0.94, and from 75 to 98 weight percent of at least one copolymer of ethylene and at least one .alpha.-olefin containing at least 4 carbon atoms, with a specific gravity between 0.905 and 0.940 and a melt index between 0.4 and 3 dg/minute, wherein the average proportion of .alpha.-olefin units in the copolymer is between 1 and 8 mole percent, wherein the copolymer comprises crystalline fractions and amorphous fractions, wherein the distribution of the .alpha.-olefin units in the copolymer is heterogeneous, and wherein the proportion of .alpha.-olefin units in the copolymer varies between at least 0.2 and at most 5 times the average proportion, depending on the fractions considered. Application to the manufacture of films with a thickness of between 5 and 200 microns.

Abstract: The danger of explosion due to decomposition of high-pressure industrial process gases, such as ethylene, is reduced by beginning to cool the decomposition gases with a delay of no more than 25 milliseconds from the onset of flow of the gases out of a high-pressure vessel.The process may be implemented by using apparatus comprising:(1) means containing an inert gas at a pressure P between about 5 and 50 bars and an inert liquid of high heat of vaporization; and(2) a valve located upstream of an inert-liquid dispersing-means, of which the opening is operated by a means detecting the opening of a safety means of the high-pressure vessel and operating the working of the dispersing means.The apparatus is useful for the recovery of decomposition gases in order to avoid atmospheric pollution, as well as for reducing the risk of explosion.

Abstract: A catalyst system for use in the polymerization of ethylene under high pressure and temperature containing an alkyl-aluminum or alkylsiloxalane activator and a compound of the formula:(TiCla) (MgCL.sub.2).sub.y (AlCl.sub.3)z (RMgCl).sub.bin whicha is from 2 to 3;y is 2 or more;z is from 0 to 1/3;b is from 0 to 1; andR is an aliphatic or aromatic hydrocarbon radical.

Abstract: A process for the manufacture of radical ethylene terpolymers or copolymers comprising moieties derived from an alkyl (meth)acrylate and/or moieties derived from maleic anhydride by copolymerizing, in the presence of at least one free-radical initiator, a mixture of ethylene, (meth)acrylate and/or maleic anhydride in a device incorporating a primary compressor, the delivery pressure of which is between 200 and 300 bars, connected to a secondary compressor which is connected directly to a polymerization reactor, fresh ethylene being fed at the intake of the said primary compressor and said copolymerization being carried out in the said polymerization reactor under a pressure of between 1,000 and 2,500 bars and a temperature of between 140.degree. and 280.degree. C., wherein at least one the alkyl (meth)acrylate and/or maleic anhydride is fed directly into the said polymerization reactor.

Abstract: A crosslinking process wherein at a temperature of about 10.degree. to 160.degree. C., under a pressure of about 1 to 300 bars and for at least about 0.5 hour, a polymer, containing from about 42 to 99% by weight of units derived from ethylene and, where appropriate, also from an .alpha.-olefin, from about 1 to 8% by weight of units derived from maleic anhydride and from 0 to about 50% by weight of units derived from at least one additional monomer selected from an ester of an unsaturated carboxylic acid with an alcohol containing from 1 to 12 carbon atoms, is reacted with at least one polyepoxide compound, preferably present in an amount of from about 1 to 10 parts by weight, based on 100 parts by weight of the polymer, in the presence of at least one catalyst suitable for reacting the anhydride functions with the epoxide functions. The catalyst is preferably present in an amount from about 0.02 to 2 parts by weight, based on 100 parts by weight of the polymer.

Abstract: Stable polyisocyanate prepolymers containing hydroxy functions, consisting of products of polyaddition of at least one organic polyisocyanate to at least one product of condensation (A) of an alkylene oxide with an amine, in the presence of at least one polyol (B) containing free hydroxy functions, in which the said polyol (B) contains primary hydroxy functions and has a molecular weight greater than or equal to 3,000.The process for their manufacture consists in reacting, at a temperature between 10.degree. and 150.degree. C., and more usually between 20.degree. and 80.degree. C., the mixture of at least one organic polyisocyanate, at least one condensation product (A) and at least one polyol (B).

Abstract: Reinforced phenolic laminates are provided with a finishing coat of a butylated phenol-formaldehyde resin, thereby removing surface irregularities. The finishing coat can be mass-pigmented to the desired color, thereby obviating the necessity of any additional color-containing coatings.

Abstract: Stable polyisocyanate prepolymers containing hydroxy functions. The prepolymers are products of the polyaddition of at least one organic polyisocyanate with at least one condensation product (A) of an alkylene oxide with an amine, in the presence of at least one polyol (B) containing free hydroxy functions. The polyol (B) contains no primary hydroxy functions and has a molecular weight of at least 1,300.The process for the manufacture of these prepolymers reacts, at a temperature between about 10.degree. and about 150.degree. C., the mixture of at least one organic polyisocyanate, at least one condensation product (A), and at least one polyol (B).

Abstract: The process according to the invention consists in dimerizing a conjugated diene in the presence of a catalyst obtained by bringing together (A) at least one nickel complex of formula NiZ.sub.q in which q is the coordination number of the nickel and Z is at least one ligand capable of complexing nickel and (B) at least one phosphorus-containing ligand of general formula ##STR1## in which: R.sub.1 is chosen from a hydrogen atom and hydrocarbon radicals,R.sub.2 and R.sub.3, which may be identical or different, are chosen from a hydrogen atom and hydrocarbon radicals optionally bearing at least one group chosen from alcohol, thiol, thioether, amine, imine, acid, ester, amide and ether groups, andm is greater than or equal to 1.

Abstract: A catalyst for the polymerization of ethylene comprising at least one halogenated compound of a transition metal of Groups IV to VI of the Periodic System and at least one aromatic silicon compound having the formula .phi..sub.n Si(OH).sub.4-n, in which .phi. is a substituted or unsubstituted aromatic or polyaromatic ring compound having from 6 to 15 carbon atoms and 1.ltoreq.n.ltoreq.3, said silicon compound being present in a molar ratio of between 0.2 and 2 inclusive with respect to said transition metal. Polymerization of ethylene may be carried out under a pressure of between 200 to 2500 bars and at a temperature of between 170.degree. and 300.degree. C. with the catalyst of this invention.

Abstract: A combination of at least one propylene polymer and at least one ethylene/.alpha.-olefin copolymer wherein the combination comprises: (a) 10 to 40 weight percent isotactic polypropylene; and (b) 60 to 90 weight percent ethylene/.alpha.-olefin copolymer, wherein said .alpha.-olefin has at least 4 carbon atoms, and wherein said copolymer has a density between 0.905 and 0.940 g/cm.sup.3 and a melt index between 0.2 and 3 dg/min. Application to the manufacture of mono-oriented yarns.

Abstract: In a process for hardening phenol-formaldehyde resol resins, comprising conducting the hardening of the resins with an acidic solution of water and/or an organic solvent having dissolved therein an aromatic sulphonic acid and/or concentrated sulphuric acid, the improvement comprising the hardening in the presence of aniline added to the phenolic resin beforehand in a quantity of between about 0.5 and 2% relative to the weight of the phenolic resin whereby the pot life is extended and the cure time is satisfactory, the resultant products being especially useful as prepegs.