Moulding composition

Abstract

The present invention relates to a moulding composition comprising polypropylene, inorganic filler and mould release composition, wherein the mould release composition comprises maleic anhydride modified polypropylene and glycol or glycerol ester of a fatty acid.

Claims

1. A moulding composition comprising polypropylene, inorganic filler and mould release composition, wherein the mould release composition is from 0.1-2.0 wt. %, based on the weight of the moulding composition and comprises maleic anhydride modified polypropylene and glycol or glycerol ester of a fatty acid, wherein the inorganic filler is selected from calcium carbonate, talc or mixture of calcium carbonate and talc, and wherein the amount of maleic anhydride modified polypropylene is from 0.05-0.9 wt. % based on the weight of the moulding composition.

2. The composition of claim 1, wherein the fatty acid is saturated fatty acid.

3. The composition of claim 1, wherein the maleic anhydride modified polypropylene contains from 0.1 to 3.0 wt. % of maleic anhydride functionalities, based on the weight of the maleic anhydride modified polypropylene.

4. The composition of claim 1, wherein the amount of maleic anhydride modified polypropylene is from 0.1 to 0.4 wt. % based on the weight of the moulding composition.

5. The composition of claim 1, wherein the amount of glycol or glycerol ester of a fatty acid is from 0.05 to 1.5 wt. % based on the weight of the moulding composition.

6. The composition of claim 1, wherein the amount of inorganic filler is from 2-30 wt. %, based on the weight of the moulding composition.

7. The composition of claim 1, further comprising ethylene -olefin copolymer elastomer.

8. The composition of claim 7, comprising from 40-90 wt. % of polypropylene, from 0.1-2 wt. % of mould release composition, from 2-30 wt. % of inorganic filler, and from 5-30 wt. % of an ethylene -olefin copolymer elastomer.

9. A moulded article comprising or consisting of the moulding composition of claim 1.

10. The moulded article of claim 9, wherein said article is an automotive interior or exterior article.

11. A method for the manufacture of a moulded article comprising injecting the composition of claim 1, in molten form into a closed mould, cooling the composition to below the melting temperature of the composition and opening the mould allowing the release of the so moulded product from said mould.

12. The composition of claim 1, wherein the amount of mould release composition is 0.3 to 1.5 wt. %, based on the weight of the moulding composition.

13. The composition of claim 2, wherein the fatty acid is stearic acid.

14. The composition of claim 6, wherein the amount of inorganic filler is from 2-30 wt. %, based on the weight of the moulding composition, and wherein the filler comprises talc.

15. The composition of claim 6, wherein the amount of inorganic filler is from 5-20 wt. %, based on the weight of the moulding composition.

16. The composition of claim 1, wherein the fatty acid is stearic acid.

17. The composition of claim 1, wherein the inorganic filler comprises talc.

18. The composition of claim 7, wherein comprising from 40-90 wt. % of the polypropylene, from 0.1-2 wt. % of the mould release composition wherein the fatty acid is stearic acid, from 2-30 wt. % talc, and from 5-30 wt. % of the ethylene -olefin copolymer elastomer.

Description

(1) In a preferred embodiment the present invention is directed at a moulding composition comprising polypropylene, inorganic filler and mould release composition, wherein the mould release composition comprises maleic anhydride modified polypropylene and glycol or glycerol ester of a fatty acid, said composition comprising from 40-90 wt. % of polypropylene from 0.1-2 wt. % of mould release composition from 2-30 wt. % of inorganic filler from 5-30 wt. % of ethylene -olefin copolymer elastomer,
all wt. % on the basis of the weight of the moulding composition.

(2) Preferred materials and ranges for the preferred embodiment are those as described herein for the individual components.

(3) The skilled person will understand that the composition according to the invention may further comprise from 0.1-5 wt. %, on the basis of the composition, of one or more additives such as anti-oxidants, pigments, dyes, nucleating agents, light stabilisers such as hindered amine light stabilisers, UV stabilisers, heat stabilisers, acid scavengers, and the like. Obviously the additives may be a mixture of at least two of the foregoing additives. Such additives are known to the skilled person.

(4) The additives may be present in an amount of up to 5 wt. %, such as from 0.1-4 wt. % or 0.3-3 wt. %. Generally the composition will contain from 0.1-1 wt. % of a stabilisation package based on the weight of the composition.

(5) In another aspect the present invention relates to a moulded article comprising or consisting of the moulding composition according to the invention.

(6) Preferably said moulded article is an automotive interior or exterior article.

(7) In yet a further aspect the present invention relates to the use of a composition comprising maleic anhydride modified polypropylene and glycol or glycerol ester of fatty acid as mould release agent in a polypropylene composition. In accordance with the foregoing said polypropylene composition preferably further comprises an inorganic filler and optionally an elastomer.

(8) In yet a further aspect the present invention relates to the use of a composition comprising maleic anhydride modified polypropylene and glycol or glycerol ester of fatty acid in a polypropylene composition for improving the mould release properties of said polypropylene composition.

(9) In yet a further aspect the present invention relates to a method for the manufacture of a moulded article comprising injecting the composition according to the present invention in molten form into a closed mould, cooling the composition to below the melting temperature of the composition and opening the mould allowing the release of the so moulded product from said mould.

(10) All references cited herein are hereby completely incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.

(11) The use of the terms a and an and the and similar referents in the context of describing the invention (especially in the context of the claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms comprising, having, including and containing are to be construed as open-ended terms (i.e., meaning including, but not limited to) unless otherwise noted. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. The use of any and all examples, or exemplary language (e.g., such as) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention. For the purpose of the description and of the appended claims, except where otherwise indicated, all numbers expressing amounts, quantities, percentages, and so forth, are to be understood as being modified in all instances by the term about. Also, all ranges include any combination of the maximum and minimum points disclosed and include any intermediate ranges therein, which may or may not be specifically enumerated herein.

(12) Preferred embodiments of this invention are described herein. Variation of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject-matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context.

(13) The claims are to be construed to include alternative embodiments to the extent permitted by the prior art.

(14) For the purpose of clarity and a concise description features are described herein as part of the same or separate embodiments, however, it will be appreciated that the scope of the invention may include embodiments having combinations of all or some of the features described.

(15) The invention will now be further illustrated by the following non-limiting examples.

(16) The Table 1 below lists the materials that were used in the Examples.

(17) TABLE-US-00001 PP1 SABIC PP 612MK10; Heterophasic propylene copolymer having a MFR of 33 g/10 min (ISO 1133, 2.16 kg, 230 C.). PP2 SABIC PP95610; Heterophasic propylene copolymer having a MFR of 5.5 g/10 min (ISO 1133, 2.16 kg, 230 C.). Elastomer Ethylene-octene copolymer elastomer having a melt flow rate of about 5 g/10 min (ISO 1133, 190 C.; 2.16 kg) and a density of about 870 kg/m.sup.3. Filler Talc HAR T84 of Luzenac having a median particle size d50 of 2 mm (sedigraph) and 11 mm (laser); a cutoff particle size d95 of 10 mm (sedigraph) and a specific surface area of 16 m2/g. CMB1 Color masterbatch based on a LDPE carrier CMB2 Color masterbatch based on a LDPE carrier AO Antioxidant Irganox B225 available from BASF MR1 Glycerol monostearate, commercially available from Croda under the trade name Atmer 129. MR2 Masterbatch of 50% propylene homopolymer and 50% of ultra high molecular weight siloxane polymer, commercially available from Dow Corning under the trade name MB50-001. MR3 Ethylene bis stearamide, commercially available from Croda under the trade name Crodamide EBSV. PPMAN Maleic anhydride modified polypropylene having a maleic anhydride content of about 0.5-1.0 wt. %, commercially available from ExxonMobil as Exxelor PO1020.

(18) MR1, MR2, MR3 are mould release agents.

(19) On the basis of these materials the following compositions were prepared.

(20) The mould release properties are indicated in a qualitative manner representing the general mould release quality based on inter alia the noise generated by removal from the mould of the injection moulded part, the ease of release of the injection moulded part from the mould and further the amount of time that the injection moulding process could be carried out without cleaning of the mould. The high improvement found for Example E1 meant that production could be carried out for at least 10 hours without interruption of the process for cleaning of the mould. The minor improvement of example CE4 meant that, with respect to the reference example, the mould release was easier initially, but that over time it got worse resulting in the need for cleaning of the mould. The indication poor means that the mould release was worse compared to the reference.

(21) TABLE-US-00002 Ref. CE1 CE2 CE3 CE4 E1 CE5 CE6 PP1 60.5 60.5 60.5 59 60.5 60.3 60.4 60.5 PP2 5 5 5 5 5 5 5 5 Elastomer 19 19 19 19 19 19 19 19 Filler 14 14 14 14 14 14 14 14 CMB1 1 1 1 1 1 1 1 CMB2 2.5 AO 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 MR1 0.3 0.4 0.5 0.3 0.3 0.3 0.2 MR2 1 MR3 0.1 0.1 PPMAN 0.2 Mould Reference No No Poor Minor High Poor Poor release effect effect improvement improvement