A process for polymerizing propylene in the presence of a polymerization catalyst by copolymerizing propylene with a comonomer selected from the group of ethylene and C4-C10 alpha-olefins in three polymerization stages. The polymer produced in the first polymerization stage has the highest melt flow rate and the lowest content of comonomer. The polymer produced in the last polymerization stage has the lowest melt flow rate and the highest content of comonomer. The polymer composition produced by the process has good mechanical properties and can be used for making pipes. The process has a good productivity.

Heterophasic polypropylene composition with improved impact strength/stiffness balance and with high flowability, reduced emissions and low shrinkage, and its use.

Polypropylene composition having a melt flow rate MFR.sub.2 (230° C.) of equal or above 15 g/10 min comprising: (a) a crystalline polypropylene matrix; (b) an elastomeric propylene copolymer phase having a propylene content in the range of 40 to 80 wt.-%, and an intrinsic viscosity in the range of more than 0.7 to less or equal 2.5 dl/g; (c) a first polyethylene having a density in the range 905 to 925 kg/m3 and melt flow rate MFR.sub.2 (190° C.) of below 30 g/10 min; (d) a second polyethylene having a density of above 915 kg/m.sup.3, and a melt flow rate MFR.sub.2 (190° C.) of equal or above 30 g/10 min.

Polyethylene composition with improved balance of impact resistance at low temperatures and Environmental Stress Cracking Resistance (ESCR), particularly suited for producing protective coatings on metal pipes, said composition having the following features: 1) density from 0.938 to 0.948 g/cm.sup.3; 2) ratio MIF/MIP from 15 to 25; 3) MIF from 30 to 45 g/10 min.; 4) Mz equal to or greater than 1000000 g/mol; 5) LCBI equal to or greater than 0.55.

A polyethylene composition which when made into a film layer having a thickness of about 1 mil exhibits a machine direction (MD) 1% secant modulus of ≥190 MPa and an oxygen transmission rate (OTR) of ≥650 cm.sup.3 per 100 inch.sup.2 per day, and when made into a film layer having a thickness of about 2 mil exhibits a seal initiation temperature (SIT) of ≤100° C. and an area of hot tack window (AHTW) of ≥160 Newtons.Math.° C.

A polyethylene-based resin composition for injection stretch blow molding may include a copolymer of ethylene and one or more C4-C8 α-olefins. The composition may have a density, according to ASTM D792, that ranges from about 0.946 to 0.960 g/cm.sup.3 and a melt index (15), as measured according to ASTM D 1238 at 190° C. under a 5.0 kg load, ranging from about 5.0 to 50 g/10 min. A method of producing an article may include injection molding the composition to give a preform; and stretch-blowing the preform to provide the article.

The present invention relates to a polyethylene resin suitable for preparing moulded articles, such as caps and closures. The invention provides in particular a polyethylene resin comprising at least two polyethylene fractions A and B, wherein said polyethylene resin has a melt index (MI2), of at least 3.0 g/10 min to at most 5.5 g/10 min as measured according to ISO 1133, condition D, at 190° C. and under a load of 2.16 kg, and a density of at least 0.955 g/cm.sup.3 to at most 0.965 g/cm.sup.3 as measured according to ISO 1183 at 23° C., and a molecular weight distribution M.sub.w/M.sub.n which is at most 7.0, as determined by gel permeation chromatography, with M.sub.w being the weight-average molecular weight and M.sub.n being the number-average molecular weight; and wherein said polyethylene fraction A has a high load melt index (HLMI), as measured according to ISO 1133:1997 condition G at 190° C. and under a load of 21.6 kg, of at least 10.5 and a melt index (MI2) of at least 0.5 g/10 min to at most 1.5 g/10 min as measured according to ISO 1133, condition D, at 190° C. and under a load of 2.16 kg. The invention further relates to a process for preparing said polyethylene resin, to a cap or closure comprising said polyethylene, and to a process for producing such a cap or closure.

A polyethylene composition for producing blow-molded hollow articles, having the following features: 1) a density from 0.945 to 0.958 g/cm.sup.3, determined according to ISO 1183 at 23° C.; 2) a ratio MIF/MI10 from 2 to 10; 3) a η.sub.0.02 from 200,000 to 800,000 Pa.Math.s; 4) a LCBI equal to or lower than 0.80; and 5) a ratio (η.sub.0.02/1000)/LCBI equal to or greater than 350.

The present invention relates to aqueous polymer latexes of film-forming copolymers obtainable by aqueous emulsion polymerisation of monomers M, which comprise at least 80% by weight, based on the monomers M, of—at least one non-ionic monomer M1, which is selected from C.sub.1-C.sub.20-alkyl esters of acrylic acid, C.sub.5-C.sub.20-cycloalkyl esters of acrylic acid, C.sub.1-C.sub.20-alkyl esters of methacrylic acid, C.sub.5-C.sub.20-cycloalkyl esters of methacrylic acid and monovinyl aromatic monomers; —one or more monoethylenically unsaturated monomers M2, which are selected from monoethylenically unsaturated monocarboxylic acids having 3 to 6 carbon atoms and monoethylenically unsaturated dicarboxylic acids having 4 to 6 carbon atoms; and where the polymer latex contains an emulsifier combination comprising i. at least one first emulsifier (1), which is selected from salts, in particular from the alkali metal salts and the ammonium salts of sulfated ethoxylated C.sub.8-C.sub.20-alkanols having a degree of ethoxylation in the range from 5 to 20 and sulfated ethoxylated tristyrylphenols having a degree of ethoxylation in the range from 5 to 20, and ii. at least one second emulsifier (2), which is selected from the salts, in particular from the alkali metal salts and the ammonium salts of a sulfated ethoxylated C.sub.8-C.sub.20-alkanol having a degree of ethoxylation in the range from 21 to 50 and sulfated ethoxylated tristyrylphenols having a degree of ethoxylation in the range from 21 to 50. The present invention also relates to a process for producing such polymer latexes and to the use of these polymer latexes as binders in waterborne coating compositions which contain at least one inorganic tannin blocking compound and to the use of such coating compositions for coating tannin-containing substrates such as wood or woodbased materials.

Polymer compositions may include a matrix phase comprising a polypropylene-based polymer; and an elastomeric rubber phase; wherein the polymer composition has melt flow rate (MFR) according to ASTM D1238 at 230° C./2.16 kg equal to or greater than 90 g/10 min and at least one feature selected from (I) an Izod impact resistance according to ASTM D256A at 23° C. equal to or greater than 400 J/m; (II) an instrumented drop impact at −30° C., average total energy, equal to or greater than 17 J; or (III) an instrumented drop impact at −30° C., average percent ductility, equal to or greater than 60%.