| 摘要 |
A film comprising a copolycarbonate, wherein the film is a uniaxially-stretched, extruded film comprising at least one film region having: an average thickness of more than 0 and less than 14 micrometers with a standard deviation of 0.8 micrometer to 1.6 micrometers, a surface having a surface roughness average of less than 0.04 micrometer as measured by optical profilometry, a dielectric constant at 1 kHz and room temperature of at least 2.7, a dissipation factor at 1 kHz and room temperature of 1% or less, and a breakdown strength of at least 620 Volt/micrometer; and the copolycarbonate has a Tg of greater than 180° C. and comprises carbonate units derived from a bisphenol compound of the formula (3). |
| 主权项 |
1. A film comprising a copolycarbonate, wherein
the film is a uniaxially-stretched, extruded film comprising at least one film region having:
an average thickness of more than 0 and less than 14 micrometers with a standard deviation of 0.8 micrometer to 1.6 micrometers,a surface having a surface roughness average of less than 0.04 micrometer as measured by optical profilometry,a delectric constant at 1 kHz and room temperature of at least 2.7,a dissipation factor at 1 kHz and room temperature of 1% or less, anda breakdown strength of at least 620 Volt/micrometer; and the copolycarbonate has a Tg of greater than 180° C. and comprises carbonate units derived from a bisphenol compound of the formula wherein
Ra and Rb are each independently a halogen atom or a monovalent hydrocarbon group,p and q are each independently integers of 0 to 4, andXa is
a C1-18 alkylene group,a C3-18 cycloalkylene group,a cycloalkylidene group comprising cyclododecylidene or adamantylidene,a fused C6-18 cycloalkylene group,a group of the formula —B1—W—B2— wherein B1 and B2 are the same or different C1-6 alkylene group and W is a C3-12 cycloalkylidene group or a C6-16 arylene group, ora substituted C3-18 cycloalkylidene of the formula whereinRr, Rp, Rq, and Rt are independently hydrogen, halogen, oxygen, or a C1-12 organic group, wherein at least two of Rr, Rp, R1, and Rt taken together are a fused cycloaliphatic, aromatic, or heteroaromatic ring,I is a direct bond, a carbon, or a divalent oxygen, sulfur, or —N(Z)— where Z is hydrogen, halogen, hydroxy, C1-12 alkyl, C1-12 alkoxy, phenyl, or C1-12 acyl, andh is 0 to 2, j is 1 or 2, i is an integer of 0 or 1, and k is an integer of 0 to 3. |
