Abstract: An ethylene polymerization catalyst having the general formula M.sub.n Mg(OR).sub.2+4n-m X.sub.m, wherein R is an alkyl radical containing from 1 to 4 carbon atoms, M is a transition metal of groups IVa to VIa of the Periodic Table, X is a halogen, 0.05.ltoreq.n.ltoreq.0.6 and 0<m<n+1.

Abstract: Shaped articles of polybut-1-ene are made by preheating a polymer blank in the crystalline form II at a temperature between 20.degree. and 90.degree. C. The preheated blank is then press-forged under a pressure between 8 and 100 kgf/mm.sup.2 for a period of 1-40 seconds. During the shaping operation, the polymer is converted into the crystalline form I. Polybut-1-ene shaped articles are formed that have a melting peak, determined by differential thermal analysis, at 119.degree. C.

Abstract: Process and device for cooling a mixture of polymer and monomer from a reactor in which ethylene is polymerized or copolymerized at a pressure greater than 1,000 bars between a pressure-reduction valve located downstream of the reactor and a medium pressure separator. The cooling is achieved by injecting monomer at a pressure below that of the separator using a device with a nozzle distance S.sub.1 and corresponding cross-section A.sub.1 the mixture from the reactor passes, a convergent mixing zone in which the mixture is mixed with the monomer injected, which is supplied at a flow rate q, and a diffuser of throat distance S.sub.3 and corresponding cross-section A.sub.3, which makes it possible to bring the mixture to the pressure of the separator. The dimensions of the device are such that the ratio Q/A.sub.1 is between 0.20 and 1.35 t/hr.mm.sup.2 and the ratio ##EQU1## is between 0.1 and 0.3 t/hr.mm.sup.2.

Abstract: In the dehydration of maleic acid to form maleic anhydride, comprising a first stage of concentrating an aqueous solution of maleic acid to 85-95% by maleic acid, and a second stage of dehydrating the concentrated maleic acid into maleic anhydride, in at least one of the stages, a falling film tubular evaporator is employed. Prior to the dehydration stage, about 15-35 parts by weight of maleic anhydride is added per 10 parts of concentrated acid.

Abstract: An embossed ethylene-propylene copolymer film having a thickness of less than or equal to 24 microns. A method and apparatus for making the film by blow-extruding the ethylene-propylene copolymer into a tubular web, pinching the tubular web between pinch rolls, and embossing the pinched web by passing it between an embossing roll and a pressure roll.

Abstract: A process of preparation of a graft copolymer of (a) styrene and (b) an EPDM rubber by mass polymerization followed by irradiation, for example electron irradiation.

Abstract: A composite film for packaging foods having at least one layer of a thermoplastic film of low density polyethylene, polypropylene, polybutene, polyamide, polystyrene or polyvinyl chloride having a thickness between 25 and 3,000 .mu.m, and another layer of a terpolymer film having a thickness between 10 and 100 .mu.m.The terpolymer film contains from 88 to 98.7 mol % of units derived from ethylene, from 1 to 10 mol % of units derived from an ester of an alkyl acrylate or an alkyl methacrylate, the alkyl group having from 1 to 6 carbon atoms, and from 0.3 to 3 mol % of units derived from maleic anhydride.

Abstract: A composition for the manufacture of hot-melt adhesives, in which the improvement comprises a terpolymer of ethylene having a melt index between 5 and 500 dg/minute and comprising from 1 to 10 mol % of units derived from an ester selected from alkyl acrylates and methacrylates, the alkyl group having from 1 to 6 carbon atoms, and from 0.3 to 3 mol % of units derived from maleic anhydride. The composition also contains at least one tackifying resin and may contain at least one compound selected from paraffin, microcrystalline polymeric wax, and esters of a hydrogenated rosinic acid and of a lower alcohol.

Abstract: A polymerization activator for polymerizing ethylene comprising a dialkylaluminum monofluoride mixed with minor amounts of at least one of dialkylaluminum hydride or halide and a trialkylaluminum. The activator preferably corresponds to the general formula (AlR.sub.2 F)(AlR.sub.2 H).sub.b (AlR.sub.3).sub.c or the general formula (AlR.sub.2 F)(AlR.sub.2 X).sub.a wherein R is an alkyl group having 1 to 12 carbon atoms, 0.1.ltoreq.b.ltoreq.0.4, 0.05.ltoreq.c.ltoreq.0.2, X is a halogen other than fluorine, and 0.1.ltoreq.a.ltoreq.0.4. The activator is used in a catalytic system including at least one halide of a transition metal of Group IVB to VIB, the valency of the metal in the halide being not more than 3 and the atomic ratio of aluminum in the activator to transition metal in the catalyst lying between 0.1 and 10. The catalytic system is used in a high pressure and temperature process for polymerizing or copolymerizing ethylene.

Abstract: A catalyst for polymerizing ethylene, especially at high temperature and high pressure, comprising at least two halogen compounds of transition metals, one of which is a titanium trichloride syncrystallized with aluminum chloride. The catalyst has the formula(TiCl.sub.3, 1/3AlCl.sub.3)(MX.sub.3).sub.x (MgX.sub.2).sub.ywherein 0.3.ltoreq.x.ltoreq.3, 0.ltoreq.y.ltoreq.20, M is a transition metal of Groups V B and VI B of the Periodic System, and X is a halogen. The second transition metal is preferably vanadium, chromium, molybdenum, or tungsten. The catalyst is made by subjecting titanium trichloride syncrystallized with aluminum chloride, the trivalent halide of M, and, optionally, anhydrous magnesium halide to a milling step in which the milling energy is at least equal to three kWh per kg of solid material treated, which results in a binary solid solution structure Ti-M of which the dimension of crystallites is less than or equal to 100 Angstroms.

Abstract: Hydrophilic cotelomers having a terminal sulphonate group, and having the formula: ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are each independently H or C.sub.1-4 alkyl; M is H or an alkali metal; M' is an alkali metal; 8.ltoreq.a.ltoreq.40 and 1.ltoreq.b.ltoreq.20. These cotelomers may also contain one or more of the following structural units, A; ##STR2## wherein R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are each independently H or C.sub.1-4 alkyl; R.sub.7 is C.sub.1-8 alkyl; R.sub.8 and R.sub.9 are each independently H or C.sub.1-2 alkyl; Y is aryl; M is H or an alkali metal; Z is M or C.sub.1-8 alkyl; 0.ltoreq.c.ltoreq.2; 0.ltoreq.d.ltoreq.3; 0.ltoreq.e.ltoreq.2; and 0.ltoreq.f.ltoreq.10. Detergent powders containing from 10 to 50% by weight of these hydrophilic cotelomers instead of sodium tripolyphosphate have good detergent and anti-redeposition powers.

Abstract: An organometallic halide having the formula:(RMX)(MX.sub.2).sub.a (MR.sub.2).sub.b (MH.sub.2).sub.cwherein a.congruent.0.45, b.congruent.0.15, and c.congruent.0.30, X is a halogen, R is a hydrocarbon radical, and M is a metal selected from the group consisting of magnesium, zinc, beryllium, and calcium is prepared by a continuous dry process by reacting an organic monohalide RX and a metal M in the form of convex solid grains of a size between 1 and 15 mm. The reaction temperature is lower than the temperature at which decomposition of the organometallic halide RMX begins and at least 10.degree. C. higher than the boiling point of the organic monohalide. The reaction may also take place in the presence of an organometallic derivative comprising a hydroxy group or an enolysable ketone group. The resulting organometallic halide may be used for the synthesis of anhydrous magnesium halide or for the reduction of titanium tetrachloride.

Abstract: There are obtained laminates of improved fire resistance comprising a substrate of reinforced phenolic resin, directly coated on at least one side thereof with a surface layer of a furan resin, and bonded to the outer surface of the furan resin a "gel-coat" of an unsaturated polyester resin, wherein the furan resin contains boron in sufficient amounts to impart an improved fire resistance to the laminates as compared to the fire resistance of the outer surface gel-coat. The boron is introduced as boric anhydride by use of a substantially anhydrous boric anhydride hardener solution to harden the furan resin.

Abstract: The invention relates to a device for the preparation and injection of sealing cement for bolts in propping gallery roofs and walls in mines, quarries or tunnels. The device of the invention comprises a flexible pouch contained in a rigid housing which is connected to a liquid supply system and an injection nozzle that is double-walled along its entire length, the inner nozzle receiving pulverulent cement from the flexible pouch and the outer ring of the nozzle being supplied with water. Thus, the cement and water are separately introduced into a bore for the bolts and the mixing process takes place in the bore.

Abstract: Furan resins of improved fire resistance are produced by curing the resins with a substantially anhydrous solution of boric anhydride, an organic solvent and a concentrated acid.

Abstract: The dielectric spacer between the conductive electrodes of an electrical capacitor is a biaxially oriented film made from a mixture of less than 80 percent by weight of isotactic polypropylene and more than 20 percent by weight of isotactic polybutene-1.

Abstract: A process for the whitening of phosphogypsum comprising treating a phosphogypsum in aqueous suspension with an amount of ozone equal to at least 150 parts by weight per million parts by weight of phosphogypsum calculated as Ca SO.sub.4.2H.sub.2 O, the pH of the aqueous suspension being lower than or equal to 3, to yield a whiteness grade of phosphogypsum higher than 75, according to French Standard NF Q 03-038.

Abstract: The energy efficiency of a high pressure, high temperature continuous process for the production of polyethylene is improved and residual gases are more completely removed from the product without detriment to product quality by employing an intermediate separator between the first and second separators. The intermediate separator is maintained at a pressure between about 10 and 70 bars, and the second separator is maintained at a pressure between about 1 and 1.5 bars.

Abstract: The danger of explosion due to decomposition of high-pressure industrial process gases, such as ethylene, is reduced by maintaining in an inert atmosphere at least part of an evacuation system included between a pressurized vessel within which the decomposition may take place, on the one hand, and the atmosphere, on the other.

Abstract: A catalytic component having the formula(MX.sub.a) (MgX.sub.2).sub.b (RMgX).sub.c (MHgX).sub.dwherein M is a metal selected from group VI B and group V B of the Periodic Classification, X is a halogen, R is a hydrocarbon radical, 2.ltoreq.a .ltoreq.3.5, 1.ltoreq.b.ltoreq.30, 1.ltoreq.c.ltoreq.8 and 0.ltoreq.d.ltoreq.10 is prepared by reducing a metallic halide of the metal M, the valency of said metal being 4 if a metal of group IV B is concerned and 4 or 5 if a metal of group V B is concerned, by means of at least one organomagnesium compound having the formula RMgX, the said organomagnesium compound being used in the solid state and reduction of the metallic halide being carried out under a pressure lower than or equal to atmospheric pressure and at a temperature lower than the decomposition point of said organomagnesium compound under the pressure concerned but at least 10.degree. higher than the boiling point or sublimation point of the metallic halide under the pressure concerned.