Molding compositions of a glass fiber-reinforced olefin polymer
View Patent ↗The invention relates to a glass fiber-reinforced molding composition composed of an olefin polymer, in particular a propylene polymer. The molding composition comprises an olefin polymer which contains 5-50% by weight of glass fibers which are bonded to the olefin polymer by means of a compatibilizer, and from 10 −4 to 1% by weight, preferably from 10 −3 to 10 31 1 % by weight, of a phthalocyanine pigment as the nucleating agent. The low costs and the fact that even a very small fraction of the phthalocyanine pigment in the polymer leads to sufficient nucleation ensures extremely inexpensive production. The nucleation with the phthalocyanine pigment leads to an improvement in the impact strength, and also in the yield stress and tensile strain at break of the molding composition.
1. A molding composition composed of an olefin polymer containing
a) from 5 to 50% by weight of glass fibers which are bonded to the olefin polymer by means of a compatibilizer, and
b) from 5×10 −3 to 5×10 −2 % by weight of a phthalocyanine pigment as a nucleating agent.
2. The molding composition as claimed in claim 1 , wherein the olefin polymer is a propylene polymer.
3. The molding composition as claimed in claim 1 , wherein the glass fibers are cut glass fibers.
4. The molding composition as claimed in claim 1 containing from 10 to 40% by weight of glass fibers.
5. The molding composition as claimed in claim 1 , wherein the compatibilizer comprises an olefin polymer functionalized with polar groups.
6. The molding composition as claimed in claim 5 , wherein the functionalized compatibilizer comprises an olefin polymer grafted with maleic anhydride and an aminosilane or epoxysilane.
7. The molding composition as claimed in claim 2 , wherein the propylene polymer is a propylene homopolymer.
8. The molding composition as claimed in claim 1 , wherein the olefin polymer has a melt-mass flow rate to ISO 1133 at 230° C. and 2.16 kg of between 0.5 and 100 g/10 min.
9. A process for producing a molding composition comprising
a) from 5 to 50% by weight of glass fibers which are bonded to a propylene polymer by means of a compatibilizer, and
b) from 5×10 −3 to 5×10 −2 % by weight of a phthalocyanine pigment as a nucleating agent,
the process comprising initially melting the propylene polymer in a mixing apparatus; mixing the melted propylene polymer with the nucleating agent at a temperature of from 180 to 320° C., thereby forming a melt; and mixing the glass fibers with the melt.
10. An article produced from a molding composition comprising:
a) from 5 to 50% by weight of glass fibers which are bonded to a propylene polymer by means of a compatibilizer, and
b) from 5×10 −3 to 5×10 −2 % by weight of a phthalocyanine pigment as a nucleating agent, the article being selected from the group consisting of a wash liquor vessel, water pump casing, and motor vehicle part.
11. The article of claim 10 wherein the motor vehicle part is a covering part.
12. The molding composition of claim 4 containing from 20 to 40% by weight of glass fibers.
13. The composition of claim 8 wherein the melt-mass flow rate is between 2 and 30 g/10 min.
14. The composition as claimed in claim 3 wherein the glass fibers have a length from 3 to 6 mm and a diameter from 10 to 20 μm.