Improving the flowability of thermoconductive polycarbonate compositions

Patent metadata

Field	Value
Publication number	US-2018201780-A1
Application number	US-201615742631-A
Country	US
Kind code	A1
Filing date	Jul 5, 2016
Priority date	Jul 8, 2015
Publication date	Jul 19, 2018
Grant date	—

Abstract

The present invention relates to the use of diglycerol esters to enhance the flowability of graphite-containing, thermally conductive polycarbonate compositions. Melt viscosities and melt volume flow rates are improved.

First claim

1 .- 11 . (canceled)

12 . A polycarbonate composition comprising
A) 20 wt % to 94.8 wt % of an aromatic polycarbonate, B) 5 to 40 wt % of graphite and C) 0.2 wt % to 3.0 wt % of diglycerol ester.

13 . The polycarbonate composition according to claim 12 comprising
0.2 to 1.2 wt % of diglycerol ester.

14 . The polycarbonate composition according to claim 12 , characterized in that as diglycerol ester an ester of formula (I) is present

where R═COC n H 2n+1 and/or R═COR′,
wherein n is an integer and R′ is a branched alkyl radical or a branched or unbranched alkenyl radical and C n H 2n+1 is an aliphatic, saturated linear alkyl radical.

15 . The polycarbonate composition according to claim 14 , characterized in that R═COC n H 2n+1 wherein n is an integer from 6-24.

16 . The polycarbonate composition according to claim 12 , characterized in that the diglycerol ester is diglycerol monolauryl ester optionally in admixture with other diglycerol esters.

17 . The polycarbonate composition according to claim 12 , characterized in that the graphite is an expanded graphite optionally in admixture with further graphite.

18 . The polycarbonate composition according to claim 12 , wherein the composition consists of
A) 74.0 wt % to 85.0 wt % of aromatic polycarbonate, B) 5 to 25 wt % of graphite, C) 0.2 to 1.2 wt % of diglycerol ester, D) optionally up to 1.0 wt % of heat stabilizer and/or transesterification stabilizer and/or E) optionally up to 10.0 wt % of one or more further additives selected from the group consisting of flame retardants, anti-dripping agents, antioxidants, inorganic pigments, carbon black, dyes, inorganic fillers, titanium dioxide, silicates, talc, barium sulfate, demolding agents, and combinations thereof.

19 . The polycarbonate composition according to claim 12 , wherein the composition consists of
A) 74.0 wt % to 79.6 wt % of aromatic polycarbonate, B) 20 to 25 wt % of graphite, C) 0.2 to 1.2 wt % of diglycerol ester, D) optionally up to 1.0 wt % of heat stabilizer and/or transesterification stabilizer and/or E) optionally up to 10.0 wt % of one or more further additives selected from the group consisting of flame retardants, anti-dripping agents, antioxidants, inorganic pigments, carbon black, dyes, inorganic fillers, titanium dioxide, silicates, talc, barium sulfate, demolding agents, and combinations thereof.

20 . Polycarbonate composition according to claim 18 , characterized in that the amount of diglycerol ester is from 0.8 to 1.2 wt %.

21 . A method comprising adding at least one diglycerol ester to enhance the melt volume flow rate determined as per DIN EN ISO 1133 (DIN EN ISO 1133-1:2012-03) at a test temperature of 300° C. with a mass of 1.2 kg to a thermally conductive polycarbonate composition comprising graphite.

22 . The method according to claim 21 , characterized in that the melt viscosity, determined as per ISO 11443, of the polycarbonate compositions is reduced by the diglycerol ester.

23 . The polycarbonate composition according to claim 14 , characterized in that R═COC n H 2n+1 wherein n is an integer from 8 to 18.

24 . The polycarbonate composition according to claim 14 , characterized in that R═COC n H 2n+1 wherein n is an integer from 10 to 16.

25 . The polycarbonate composition according to claim 14 , characterized in that R═COC n H 2n+1 wherein n is 12.

Assignees

• Covestro Deutschland Ag

Inventors

• Heuer Helmut Werner
• Wehrmann Rolf
• Boumans Anke
• Erkelenz Michael

Classifications

• C08K3/013

  Fillers, pigments or reinforcing additives · CPC title

• C08K3/30

  Sulfur-, selenium- or tellurium-containing compounds · CPC title

• C08K5/103 Primary

  with polyalcohols · CPC title

• C08K2201/001

  Conductive additives · CPC title

• C08K3/04 Primary

  Carbon · CPC title