Abstract: Disclosed are biaxially stretched polyolefin films containing a) 10 to 45% by weight of a cycloolefin polymer with a glass transition temperature between 120 and 170° C., and b) 90 to 55% by weight of a semi-crystalline alpha-olefin polymer with a crystallite melting temperature between 150 and 170° C., wherein the glass transition temperature of component a) being less than or equal to the crystallite melting temperature of component b), and wherein the polyolefin film has a shrinkage at 130° C. after 5 minutes, as measured according to ISO 11501, of less than or equal to 2%. These polyolefin films are excellent suited as dielectrics for capacitors but also for other applications and are distinguished by a low shrinkage at high temperatures.
Abstract: The invention relates to selected polymer blends which can be used for production of films or sheets having reduced defects, and also to a process for preparation of the polymer blends.
Abstract: Cycloolefin copolymers which are distinguished by the presence of racemic diads of repeating polycyclic units and additionally by racemic triads of repeating polycyclic units are described. These copolymers can be prepared by copolymerization of polycyclic olefins with linear olefins in the presence of metallocene catalysts which have no Cs symmetry in relation to the centroid-M-centroid plane. The novel copolymers can be used for the production of shaped articles, in particular of films.
Type:
Grant
Filed:
March 19, 2008
Date of Patent:
August 7, 2012
Assignee:
Topas Advanced Polymers GmbH
Inventors:
Dieter Ruchatz, Anne-Meike Schauwienold, Peter Jörg
Abstract: Cycloolefin copolymers which are distinguished by the presence of racemic diads of repeating polycyclic units and additionally by racemic triads of repeating polycyclic units are described. These copolymers can be prepared by copolymerization of polycyclic olefins with linear olefins in the presence of metallocene catalysts which have no Cs symmetry in relation to the centroid-M-centroid plane. The novel copolymers can be used for the production of shaped articles, in particular of films.
Type:
Grant
Filed:
March 19, 2008
Date of Patent:
March 20, 2012
Assignee:
Topas Advanced Polymers GmbH
Inventors:
Dieter Ruchatz, Anne-Meike Schauwienold, Peter Jörg
Abstract: A novel cycloolefin copolymer that can be employed in the production of molding with fewer defects, for example, fewer gel particles (fish eyes). There is provided a cycloolefin copolymer comprising 80 to 20 mol % of repeating units derived from an ?-olefin monomer and 20 to 80 mol % of repeating units derived from at least one cycloolefin monomer selected from the group consisting of monomer of the general formula (I), monomer of the general formula (II), monomer of the general formula (III), monomer of the general formula (IV) and monomer of the general formula (V), wherein with respect to the repeating units derived from cycloolefin monomer, the proportion thereof being present in the form of dimer (Rd) is 50 mol % or below and the proportion thereof being present in the form of trimer (Rt) 5 mol % or above.