Biaxially oriented electrical insulating film
AssigneeBorealis Technology Oy
InventorsDetlef Busch, Thilo Mohr
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Abstract
The invention relates to a biaxially oriented electrical insulating film which is constituted of a base layer and at least one cover layer, the base layer containing a mixture from a polypropylene P1 and a polypropylene P2 which is different therefrom, the polypropylene P1 being a linear polypropylene and having an Mw/Mn>5 and a mesopentadene isotactic index of at least 95% and the polypropylene P2 having a long-chain branching.
Claims21
A biaxially-oriented electrical insulating film comprising a base layer and at least one covering layer, wherein said base layer comprises a mixture of a polypropylene P1 and a different polypropylene P2, wherein said polypropylene P1 is a linear polypropylene and has an Mw/Mn of greater than 5 and a mesopentadene isotaxy in the range of from 96.5% to 99.5% and said polypropylene P2 has
- (i) a long-chain branching, and wherein the branching index g′ of said polypropylene P2 is in the range of from 0.6 to 0.8,
- (ii) an average molecular weight Mw of polymer P2, determined by means of GPC is in the range of 400,000 to 650,000,
- (iii) has a ratio Mw/Mn of greater than 5 to 10,
- (iv) has a triad-related chain isotaxy index of 93 to 98%,
- (v) has an ash content of 10 to 40 ppm, and
- (vi) a chlorine content of greater than 0 to 5 ppm and
- wherein the base layer further contains an additive selected from the group consisting of a neutralization agent and a stabilizer.
Dependencies are inferred from the claim text.