A bimodal polymer composition comprising a lower molecular weight homopolymer and a higher molecular weight copolymer wherein the bimodal polymer composition has a density of from about 0.930 gram per cubic centimeter (g/cc) to about 0.970 g/cc, a ratio of high load melt index:melt index of from about 10 to about 150 and an Environmental Stress Crack Resistance (ESCR) of from about 25 hours to about 300 hours when measured in accordance with ASTM D1693 or ASTM D2561. A chromium-catalyzed polymer composition comprising (i) a lower molecular weight homopolymer and (ii) a higher molecular weight copolymer, wherein the bimodal polymer composition has an Environmental Stress Crack Resistance (ESCR) of from about 25 hours to about 300 hours when measured in accordance with ASTM D1693 or ASTM D2561.

The present invention relates to a process for producing a propylene polymer, such as a propylene homopolymer, a propylene-ethylene random copolymer or a heterophasic propylene copolymer using a specific class of metallocene complexes in combination with a cocatalyst system comprising a boron containing cocatalyst and an aluminoxane cocatalyst, preferably in a multistage polymerization process including a gas phase polymerization step.

The present invention relates to a process for producing a propylene polymer, such as a propylene homopolymer, a propylene-ethylene random copolymer or a heterophasic propylene copolymer using a specific class of metallocene complexes in combination with a cocatalyst system comprising a boron containing cocatalyst and an aluminoxane cocatalyst, preferably in a multistage polymerization process including a gas phase polymerization step.

An emulsion polymerization process for preparation of ABS graft copolymer latex having reduced residual monomer content, wherein a grafting step c) comprises the steps: c1): feeding of 10 to 45 wt.-% of styrene and acrylonitrile in one portion to agglomerated butadiene rubber latex and addition of redox system initiator, then polymerization; c2): feeding remaining monomers in portions or continuously and further addition of redox system initiator; c3): addition of inorganic free radical initiator and continuation of polymerization, leads to ABS graft copolymers and thermoplastic molding compositions which can be used in the automotive industry.

A method capable of stably performing continuous production of a propylene polymer with high productivity while reducing generation of agglomerates is described. In the method, a monomer(s) containing propylene is/are (co)polymerized in a presence of an olefin polymerization catalyst with a polymerization system containing two or more gas phase polymerization reactors or a polymerization system containing a liquid phase polymerization reactor(s) and a gas phase polymerization reactor(s) such that that the total number of liquid phase polymerization reactor(s) and gas phase polymerization reactor(s) is three or more. In at least one gas phase polymerization reactor, an average retention time τ.sub.G [hour] in the gas phase polymerization, an average particle diameter D.sub.pi [μm] of fed powder, and a total amount C.sub.o [wt %] of an ethylene-derived structural unit and C4-C12 α-olefin-derived structural units in a polymer in discharged powder are in a predetermined relationship.

A method capable of stably performing continuous production of a propylene polymer with high productivity while reducing generation of agglomerates is described. In the method, a monomer(s) containing propylene is/are (co)polymerized in a presence of an olefin polymerization catalyst with a polymerization system containing two or more gas phase polymerization reactors or a polymerization system containing a liquid phase polymerization reactor(s) and a gas phase polymerization reactor(s) such that that the total number of liquid phase polymerization reactor(s) and gas phase polymerization reactor(s) is three or more. In at least one gas phase polymerization reactor, an average retention time τ.sub.G [hour] in the gas phase polymerization, an average particle diameter D.sub.pi [μm] of fed powder, and a total amount C.sub.o [wt %] of an ethylene-derived structural unit and C4-C12 α-olefin-derived structural units in a polymer in discharged powder are in a predetermined relationship.

Multiphase polymers comprising crosslinking monomers and polyfunctional amine are disclosed. The multiphase polymer comprises a first phase polymer having a Tg from 60° C. to 240° C., a second phase polymer having a Tg from 40° C. to 240° C., and a soft phase polymer having a Tg from -25° C. to 30° C. The crosslinking monomers include a triacrylate such as trimethylol propane triacrylate, an unsaturated alkoxysilane, and an unsaturated keto monomer reactive with the polyfunctional amine. In contrast to conventional knowledge, incorporation of trimethylolpropane triacrylate reduces the minimum film forming temperature of multiphase polymers. This unusual reduction in MFFT helps to reduce the VOC requirement to form a good film at low VOC. The other crosslinking monomers including unsaturated alkoxy silane and unsaturated keto monomer which react with the polyfunctional amine improve print resistance, block resistance and lower the tackiness of paint films. The multiphase polymer is particularly suitable for use in deep base paints.

The present invention relates to a method of preparing a polymer, which includes: adding a first reaction solution including an aqueous solvent and a monomer mixture including an alkyl-substituted aromatic vinyl-based monomer, an alkyl-unsubstituted aromatic vinyl-based monomer, and a vinyl cyanide-based monomer to a reactor and initiating polymerization; and performing polymerization by continuously adding an alkyl-substituted aromatic vinyl-based monomer to the reactor, wherein the first reaction solution satisfies Expression 1 (see the description of the invention).

The present invention relates to a method of preparing a polymer, which includes: adding a first reaction solution including an aqueous solvent and a monomer mixture including an alkyl-substituted aromatic vinyl-based monomer, an alkyl-unsubstituted aromatic vinyl-based monomer, and a vinyl cyanide-based monomer to a reactor and initiating polymerization; and performing polymerization by continuously adding an alkyl-substituted aromatic vinyl-based monomer to the reactor, wherein the first reaction solution satisfies Expression 1 (see the description of the invention).

Blown films, especially monolayer blown films, with an improved property profile, the blown films comprising at least 95.0 wt% of a specific heterophasic propylene copolymer (TERHECO).