Thermal plastic blends with improved impact strength and flow
View Patent ↗Disclosed herein are blended thermoplastic compositions comprising at least one polycarbonate polymer, at least one polyester polymer, and at least one reinforcing filler. The thermal blended polycarbonate compositions can optionally further comprise at least one polycarbonate-polysiloxane copolymer, at least one impact modifier polymer, and/or at least one flame retardant. The resulting compositions can be used in the manufacture of articles requiring materials with high modulus and high flowability, while retaining good impact strength. This abstract is intended as a scanning tool for purposes of searching in the particular art and is not intended to be limiting of the present disclosure.
1. A blended thermoplastic composition comprising:
a. from about 30 wt % to about 75 wt % of a polycarbonate polymer;
b. from about 1 wt % to about 15 wt % of a polyester polymer; and
c. from greater than 30 wt % to about 60 wt % of a reinforcing filler;
wherein the combined weight percent value of all components does not exceed about 100 wt %;
wherein all weight percent values are based on the total weight of the composition; and
wherein a molded sample of the blended thermoplastic composition has an unnotched Izod impact strength when determined in accordance with ASTM D4812 of at least about 15% greater than a reference composition comprising substantially the same proportions of the same polycarbonate polymer component and the same reinforcing fiber, in the absence of the polyester polymer.
2. The composition of claim 1 , wherein the polycarbonate is a homopolymer.
3. The composition of claim 2 , wherein the homopolymer comprises repeating units derived from bisphenol A.
4. The composition of claim 1 , wherein the polycarbonate is a copolymer.
5. The composition of claim 4 , wherein the copolymer comprises repeating units derived from sebacic acid or bisphenol A, or both.
6. The composition of claim 1 , wherein the polycarbonate polymer is present in an amount from about 45 wt % to about 70 wt %.
7. The composition of claim 1 , wherein the polyester polymer comprises polybutylene terephthalate or polyethylene terephthalate, or both.
8. The composition of claim 1 , wherein the polyester polymer is present in an amount from about 3 wt % to about 15 wt %.
9. The composition of claim 1 , further comprising a polycarbonate-polysiloxane copolymer.
10. The composition of claim 9 , wherein the polycarbonate-polysiloxane copolymer comprises a polysiloxane block from about 5 wt % to about 30 wt % of the polycarbonate-polysiloxane copolymer.
11. The composition of claim 9 , wherein the polycarbonate-polysiloxane is present in an amount greater than about 0 wt % to about 15 wt %.
12. The composition of claim 1 , further comprising an impact modifier.
13. The composition of claim 12 , wherein the impact modifier component comprises at least one acrylonitrile-butadiene-styrene (ABS) polymer, at least one bulk polymerized ABS (BABS) polymer, or at least one methyl methacrylate-butadiene-styrene (MBS) polymer.
14. The composition of claim 12 , wherein the impact modifier is present is an amount greater than about 0 wt % to about 10 wt %.
15. The composition of claim 1 , further comprising at least one flame retardant.
16. The composition of claim 15 , wherein the at least one flame retardant is a phosphorus-containing flame retardant.
17. The composition of claim 16 , wherein the phosphorus-containing flame retardant is an aromatic cyclic phosphazene compound.
18. The composition of claim 16 , wherein the phosphorus-containing flame retardant comprises rescorcinol bis(diphenyl phosphate), resorcinol bis(dixylenyl phosphate), hydroquinone bis(diphenyl phosphate), bisphenol-A bis(diphenyl phosphate), 4,4′-biphenol bis(diphenyl phosphate), triphenyl phosphate, methylneopentyl phosphite, pentaerythritol diethyl diphosphite, methyl neopentyl phosphonate, phenyl neopentyl phosphate, pentaerythritol diphenyldiphosphate, dicyclopentyl hypodiphosphate, dineopentyl hypophosphite, phenylpyrocatechol phosphite, ethylpyrocatechol phosphate or dipyrocatechol hypodiphosphate, or a combination thereof.
19. The composition of claim 15 , wherein the flame retardant is present in an amount from greater than about 0 wt % to about 15 wt %.
20. The composition of claim 1 , further comprising at least one additive selected from an anti-drip agent, antioxidant, antistatic agent, chain extender, colorant, de-molding agent, dye, flow promoter, flow modifier, light stabilizer, lubricant, mold release agent, pigment, quenching agent, thermal stabilizer, UV absorbent substance, UV reflectant substance, and UV stabilizer, or combinations thereof.
21. The composition of claim 1 , further comprising an anti-drip agent present in an amount from about 0.05 wt % to about 3 wt %.
22. The composition of claim 21 , wherein the anti-drip agent is a styrene-acrylonitrile copolymer encapsulated polytetrafluoroethylene.
23. The composition of claim 21 , wherein the antioxidant is a primary antioxidant, a secondary antioxidant, or combinations thereof.
24. The composition of claim 23 , wherein the primary antioxidant is selected from the group consisting of a hindered phenol and secondary aryl amine, or a combination thereof.
25. The composition of claim 23 , wherein the secondary anti-oxidant is selected from the group consisting of an organophosphate and thioester, or a combination thereof.
26. An article comprising the compositions of claim 1 .
27. The article of claim 26 , wherein the article is selected from the group consisting of a computer device, electromagnetic interference device, printed circuit, Wi-Fi device, Bluetooth device, GPS device, cellular antenna device, smart phone device, automotive device, medical device, sensor device, security device, shielding device, RF antenna device, LED device and RFID device.
28. A blended thermoplastic composition comprising:
a. from about 30 wt % to about 75 wt % of a polycarbonate polymer;
b. from about 1 wt % to about 15 wt % of a polyester polymer;
c. from about 25 wt % to about 60 wt % of a reinforcing filler;
d. from about 1 wt % to about 15 wt % of a flame retardant; and
e. from about 1 wt % to about 15 wt % of an impact modifier polymer, wherein the impact modifier in not an acrylonitrile-butadiene-styrene (ABS) polymer;
wherein the combined weight percent value of all components does not exceed about 100 wt %;
wherein all weight percent values are based on the total weight of the composition;
wherein the blended thermoplastic composition has a melt volume rate (MVR) when determined in accordance with ASTM 1238 at 300° C. under a load of 1.2 kg of at least about 10% greater than a reference composition comprising substantially the same proportions of the same polycarbonate polymer component and the same reinforcing fiber, in the absence of the polyester polymer; and
wherein a molded sample of the blended thermoplastic composition has an unnotched Izod impact strength when determined in accordance with ASTM D4812 of at least about 15% greater than a reference composition comprising substantially the same proportions of the same polycarbonate polymer component and the same reinforcing fiber, in the absence of the polyester polymer.
29. A method of preparing a composition, comprising mixing:
a. from about 30 wt % to about 75 wt % of a polycarbonate polymer;
b. from about 1 wt % to about 15 wt % of a polyester polymer;
c. from about 1 wt % to about 15 wt % of a flame retardant; and
d. from about 30 wt % to about 60 wt % of a reinforcing filler;
wherein the combined weight percent value of all components does not exceed about 100 wt %;
wherein all weight percent values are based on the total weight of the composition;
wherein the blended thermoplastic composition has a melt volume rate (MVR) when determined in accordance with ASTM 1238 at 300° C. under a load of 1.2 kg of at least about 10% greater than a reference composition comprising substantially the same proportions of the same polycarbonate polymer component and the same reinforcing filler, in the absence of the polyester polymer; and
wherein a molded sample of the blended thermoplastic composition has an unnotched Izod impact strength when determined in accordance with ASTM D4812 of at least about 15% greater than a reference composition comprising substantially the same proportions of the same polycarbonate polymer component and the same reinforcing fiber, in the absence of the polyester polymer.
30. The method of claim 29 , where mixing comprises the steps of:
a. pre-blending from about 30 wt % to about 75 wt % of a polycarbonate polymer powder with from about 1 wt % to about 15 wt % of a flame retardant to provide a pre-blended polycarbonate polymer and flame retardant;
b. feeding the pre-blended polycarbonate polymer and flame retardant into an extruder apparatus;
c. compounding in the extruder apparatus the pre-blended polycarbonate polymer and flame retardant with from about 1 wt % to about 15 wt % of a polyester polymer; and
in a downstream extruder zone feeding into the extruder apparatus from greater than 30 wt % to about 60 wt % of a reinforcing filler.
31. The composition of claim 1 , wherein the reinforcing filler comprises glass beads, glass fiber, glass flakes, mica, talc, clay, wollastonite, zinc sulfide, zinc oxide, carbon fiber, ceramic-coated graphite, or titanium dioxide, or a combination thereof.
32. The composition of claim 1 , wherein the reinforcing filler comprises glass fiber.
33. The composition of claim 32 , wherein the glass fiber has a diameter from about 4 μm to about 15 μm.
34. The composition of claim 32 , wherein the glass fiber is present in an amount from about 50 wt % to about 60 wt %.