阅读说明：本技术 在聚四氟乙烯基体中具有改善的锚固的含有纤维的填料颗粒 (Fiber-containing filler particles with improved anchoring in polytetrafluoroethylene matrix ) 是由 I·奥利格斯-施塔德勒 于 2018-06-13 设计创作，主要内容包括：本发明涉及含有纤维的填料颗粒，其中两种或更多种纤维被至少部分地包封在固体颗粒中，所述固体颗粒由选自聚苯硫醚、液晶聚合物、聚苯砜、聚醚砜、热塑性聚酰亚胺、聚酰胺酰亚胺、环氧树脂、全氟烷氧基聚合物和上述聚合物中的两种或更多种的任何期望混合物的聚合物构成，其中与包封在固体颗粒中的端部相对的纤维中的至少部分的端部从固体颗粒中突出，其中含有纤维的填料颗粒的最大长度为1000μm，并且纤维的最大厚度为100μm。这样的含有纤维的填料颗粒可以通过以下步骤获得：将聚合物与纤维混合，熔融聚合物和/或聚合物组分的化学反应，冷却熔融聚合物和纤维的混合物以得到固体纤维?聚合物复合材料，和粉碎纤维?聚合物复合材料以得到最大长度为1000μm的含有纤维的填料颗粒。(The invention relates to a fiber-containing filler particle, wherein two or more fibers are at least partially encapsulated in a solid particle composed of a polymer selected from the group consisting of polyphenylene sulfide, liquid crystal polymers, polyphenylsulfones, polyethersulfones, thermoplastic polyimides, polyamideimides, epoxies, perfluoroalkoxy polymers, and any desired mixtures of two or more of the foregoing polymers, wherein at least a portion of the ends of the fibers opposite the ends encapsulated in the solid particle protrude from the solid particle, wherein the maximum length of the fiber-containing filler particle is 1000 μm and the maximum thickness of the fibers is 100 μm. Such fiber-containing filler particles can be obtained by the following steps: mixing a polymer with fibres, melting the polymer and/or a chemical reaction of the polymer components, cooling the mixture of molten polymer and fibres to obtain a solid fibre-polymer composite, and comminuting the fibre-polymer composite to obtain fibre-containing filler particles having a maximum length of 1000 μm.)

1. A fiber-containing filler particle, wherein two or more fibers are at least partially encapsulated in a solid particle comprised of a polymer selected from the group consisting of polyphenylene sulfide, liquid crystal polymers, polyphenylsulfones, polyethersulfones, thermoplastic polyimides, polyamideimides, epoxies, perfluoroalkoxy polymers, and any mixture of two or more of the foregoing, wherein at least a portion of the ends of the fibers opposite the ends encapsulated in the solid particle protrude from the solid particle, and the fiber-containing filler particle has a maximum longitudinal dimension of 1000 μ ι η and a fiber thickness of no more than 100 μ ι η.

2. Fiber-containing filler particles according to claim 1, characterized in that the solid particles contain polyphenylene sulfide as polymer.

3. Fibrous filler particle according to claim 2, characterized in that the solid particles contain crosslinked polyphenylene sulfide as polymer.

4. Fiber-containing filler particles according to at least one of the preceding claims, characterized in that more than 2, preferably more than 5, and particularly preferably more than 10 fibers are partially encapsulated therein.

5. Fiber-containing filler particles according to at least one of the preceding claims, characterized in that the fibers are selected from carbon fibers, glass fibers, polymer fibers, ceramic fibers, metal fibers and any mixtures of two or more of the aforementioned fibers.

6. Fibrous-containing filler particles according to at least one of the preceding claims, characterized in that the fibres are carbon fibres.

7. Fiber-containing filler particles according to at least one of the preceding claims, characterized in that the thickness of the fibers is from 1 to 100 μm, preferably from 2 to 75 μm, particularly preferably from 5 to 50 μm, and very particularly preferably from 6 to 20 μm.

8. Fiber-containing filler particles according to at least one of the preceding claims, characterized in that the ends of at least part of the fibers opposite to the ends encapsulated in the solid particles protrude from the solid particles by 1 to 100 μm, and preferably by 10 to 50 μm.

9. Fiber-containing filler particles according to at least one of the preceding claims, characterized in that the ends of at least 2, preferably at least 5, and particularly preferably at least 10 fibers opposite the ends encapsulated in the solid particles protrude from the solid particles.

10. Fiber-containing filler particles according to at least one of the preceding claims, characterized in that the maximum length of the fiber-containing filler particles is from 1 to 1000 μm, preferably from 5 to 500 μm, and particularly preferably from 10 to 200 μm.

11. A composite material consisting of a matrix consisting of polytetrafluoroethylene, wherein the composite material contains fiber-containing filler particles according to any one of the preceding claims in the matrix.

12. A process for preparing fiber-containing filler particles according to at least one of claims 1 to 10, comprising the steps of:

a) mixing fibers having a thickness of not more than 100 μm with a polymer selected from the group consisting of polyphenylene sulfide, liquid crystal polymers, polyphenylsulfones, polyethersulfones, thermoplastic polyimides, polyamideimides, epoxies, perfluoroalkoxy polymers, and any mixture of two or more of the foregoing polymers, wherein the fibers have a higher melting point than the polymer to obtain a fiber-polymer mixture,

b1) melting the fiber-polymer mixture obtained in step a) at a temperature above the melting point of the polymer but below the melting point of the fiber to obtain a fiber-melt mixture, or

b2) Curing the polymer component of the fiber-polymer mixture obtained in step a) by a chemical reaction to obtain a fiber-polymer composite,

c) optionally cooling the fiber-polymer composite obtained in step b1) or b2), and

d) comminuting the fiber-polymer composite obtained in step c) to obtain fiber-containing filler particles having a maximum length of 1000 μm.

13. The process as claimed in claim 12, characterized in that polyphenylene sulfide is used as polymer in step a) and process steps b1), c) and d) are carried out under an air atmosphere in order to crosslink the polyphenylene sulfide.

14. The method according to claim 12 or 13, characterized in that the fiber-polymer composite is comminuted in step c) to obtain fiber-containing filler particles having a maximum longitudinal dimension of 1 to 1000 μm, preferably 5 to 500 μm, and particularly preferably 10 to 200 μm.

15. The method according to at least one of the claims 12 to 14, characterized in that the comminution of the fiber-polymer composite in step c) is carried out by grinding or preferably by crushing.

Examples

800g of powdered polyphenylene sulfide were mixed with 400g of carbon fibers having a fiber length of 150 μm and a fiber diameter of 15 μm, and the resulting mixture was distributed on a metal plate. The mixture on the metal plate was then heated at 300 ℃ for 6 hours to melt polyphenylene sulfide having a melting point of 285 ℃. The mixture is subsequently cooled and the solidified fibre-containing polymer melt is comminuted by means of a high-performance mixer, for example comprising a beater device, blades or knives, or by means of a grinder, for example, to give fibre-containing filler particles having an average diameter of 50 μm.

The following mixtures were then prepared:

63% by weight of PTFE in the form of pellets,

35% by weight of the above polyphenylene sulfide particles containing carbon fibers, and

2% by weight of graphite.

The mixture was then treated at 370 ℃ for 3 hours to give a composite, and then cooled to room temperature. The composite material thus prepared showed excellent adhesion of the polyphenylene sulfide particles containing carbon fibers to PTFE.