A semicrystalline multiblock copolymer includes alternating blocks of semicrystalline isotactic polypropylene (iPP) and semicrystalline polyethylene (PE), having a block arrangement according to formula (I):
(iPP.sub.w).sub.p(PE.sub.x)(iPP.sub.y).sub.m(PE.sub.z).sub.n   (I),
wherein p is 0 or 1; m is 0 or 1; n is 0 or 1; the sum of p, m, and n is 1, 2, or 3; and the sum of w, x, y, and z is greater than or equal to 40 kg/mol, with the provisos that: when m and n are 0, the sum of w and x is greater than or equal to 140 kg/mol; and when p and n are 0, the sum of y and x is greater than or equal to 140 kg/mol. Related compositions and methods are also provided.

The present invention relates to a polyolefin-polystyrene multi-block copolymer having a structure comprising a polyolefin block and polystyrene blocks bonded to both ends of the polyolefin block, to an organozinc compound for preparing the same, and a method for preparing the polyolefin-polystyrene multi-block copolymer.

A polypropylene resin composition is provided that includes an ethylene-propylene block copolymer resin. The ethylene-propylene block copolymer resin comprises a propylene homopolymer component and an ethylene-propylene rubber copolymer component as a solvent extract. The content of the ethylene-propylene rubber copolymer component in the ethylene-propylene block copolymer resin is 25 to 40% by weight. The ratio of the content of ethylene to the content of solvent extract in the ethylene-propylene block copolymer resin based on percent by weight is 0.25 to 0.45/ The ethylene-propylene block copolymer resin has a melt index of 20 to 45 g/10 minutes when measured at 230° C. under a load of 2.16 kg.

Semi-crystalline, thermoplastic polyolefin block copolymers comprising: (A) A first polyolefin A block comprising isotactic poly(1-butene) (iPB); (B) A polyolefin B block comprising an ethylene and/or alpha-olefin/1-butene copolymer or terpolymer; and (C) A second polyolefin A block comprising isotactic poly(1-butene) (iPB); the A and B blocks bonded to one another to form a block copolymer in which the first and second polyolefin A blocks are joined to and separated by the polyolefin B block. In one embodiment the polyolefin block copolymer is a BAB block copolymer.

A method of fused filament fabrication (FFF) additive manufacturing comprises employing an olefin block copolymer. The method allows for the additive manufacturing article that retains the desirable mechanical properties of polyolefins such as polyethylene or polypropylene without experiencing the problems inherent in FFF printing of polyethylene or polypropylene particularly in the absence of solid fillers. In a particular embodiment, the additive manufactured article is comprised of the olefin block copolymer is comprised of block composite or crystalline block composite polymer or mixture thereof comprising the olefin block copolymer, wherein the olefin block copolymer is comprised of an isotactic propylene block and a polyethylene rich block.

In a polypropylene-based foamed molded body of the present invention, a density which is measured on the basis of ISO1183 is greater than or equal to 0.15 g/cm.sup.3 and less than or equal to 0.54 g/cm.sup.3, thermal resistance (R) at 30° C. in a thickness direction which is measured on the basis of ASTM E1530 is greater than or equal to 0.020 m.sup.2.Math.K/W and less than or equal to 0.125 m.sup.2.Math.K/W, thermal capacity per unit area (Q) at 30° C. is greater than or equal to 1.0 kJ/m.sup.2.Math.K and less than or equal to 2.5 kJ/m.sup.2.Math.K, and Expression 1 described below is satisfied.
Q>1/(4×R.sup.1/2)  (Expression 1)

The present disclosure relates to an olefin polymerization catalyst system for use in forming a multi-block copolymer, said copolymer containing therein two or more segments or blocks differing in chemical or physical properties, a polymerization process using the same, and the resulting polymers, wherein the catalyst system comprises: (A) a first olefin polymerization procatalyst, (B) a second olefin polymerization procatalyst capable of preparing polymers differing in chemical or physical properties from the polymer prepared by procatalyst (A) under equivalent polymerization conditions, and (C) a chain shuttling agent.

A block copolymer composition is disclosed herein. In some embodiments, a block copolymer composition has a weight average molecular weight (M.sub.w) of 70,000 g/mol to 120,000 g/mol, a polydispersity index (PDI) of 1.0 to 2.0, a glass transition temperature (T.sub.g) of −55° C. to −30° C., and a melt index (MI), measured at 230° C. and a loading condition of 5 kg, of 0.2 g/10 minutes to 3.0 g/10 minutes. The block copolymer composition has excellent processability.

It is provided a refrigerator appliance (1) having at least one internal liner (2), in particular a cabinet liner or a door liner, defining an inner compartment (3) and made of a polypropylene-based material comprising a propylene-ethylene copolymer having a main polypropylene chain with ethylene units arranged along the polypropylene chain; and at least one lamellar or fibrolamellar filler. The material makes it possible to effectively manufacture the liner (2) by thermoforming.

Provided is a cyclic olefin-based resin composition for molding containing a resin (A) which contains a structural unit (a1) derived from an -olefin and a structural unit (a2) derived from a cyclic olefin, has a glass transition temperature in both a region equal to or lower than 50 C. and a region equal to or higher than 125 C. in a case where the composition is subjected to differential scanning calorimetry, and has a dispersity within a range of 1.0 to 1.6 measured by gel permeation chromatography. Also provided is a molded product formed of the composition and the resin (A).