Production method of flame-retardant antistatic CPP film

Abstract

The invention discloses a production method of a flame-retardant antistatic CPP film. The CPP film is composed of an outer surface layer, a base layer and an inner surface layer. The outer surface layer is prepared from PP (polypropylene), HDPE (high-density polyethylene), carbon black, ammonium polyphosphate and dipentaerythritol; the base layer is composed of PP, LDHs, ammonium polyphosphate, pentaerythritol and a silane coupling agent; the inner surface layer is composed of PP, HDPE, carbon black, ammonium polyphosphate and dipentaerythritol. The flame-retardant antistatic plastic has a good flame-retardant effect, is antistatic, and also keeps relatively high bending strength and notch impact strength.

Description

Technical Field

[0001] The invention relates to a method for producing a flame-retardant and antistatic CPP film. Background Art

[0002] As a semi-crystalline thermoplastic polymer material, polypropylene has the advantages of good heat resistance, low density, stress cracking resistance, easy molding and processing, and low price. CPP film is cast polypropylene film, also known as unstretched polypropylene film. PP is widely used in industrial fields, but its flammability and electrostatic aggregation characteristics may cause fire accidents in the fields of petrochemicals, coal, and hazardous dust emissions. At present, the flame retardant and antistatic technology of polymers is mainly based on the addition of halogen flame retardants and surfactant antistatic agents. In actual use, there are problems such as poor durability of antistatic performance, large amount of filler added, poor mechanical properties, large smoke production, high toxicity of smoke, and strong corrosiveness. Summary of the invention

[0003] In view of the above-mentioned defects of the prior art, the object of the present invention is to provide a method for producing a flame retardant and antistatic CPP film.

[0004] To solve the above problems, the technical solution of the present invention is: a method for producing a flame retardant and antistatic CPP film, wherein the CPP film is composed of an outer surface layer, a base layer and an inner surface layer; The outer layer is composed of PP, HDPE, carbon black, ammonium polyphosphate, and dipentaerythritol; The base layer is composed of PP, LDHs, ammonium polyphosphate, pentaerythritol and silane coupling agent; The inner surface layer is composed of PP, HDPE, carbon black, ammonium polyphosphate, and dipentaerythritol; The production method comprises the following steps: (1) The ammonium polyphosphate and dipentaerythritol of the outer layer are compounded into a halogen-free intumescent flame retardant, and then PP, HDPE and carbon black are added to blend together. The inner layer raw material blending method is the same as that of the outer layer; the ammonium polyphosphate of the base layer is blended with LDHs to form a powder, and then pentaerythritol and silane coupling agent are added to mix by ball milling, and finally PP is added to blend; (2) The raw materials of the outer layer, base layer and inner layer are fed into respective extruders for mixing and plasticizing; (3) The molten melts are fed into the die heads respectively, and the melts are combined in the die heads and then pass through the flat die head opening to form a molten sheet; (4) Using an air knife to attach the sheet to a chilled roller to quench it into an unshaped sheet, and then cooling it in a water bath to shape the sheet into a film; (5) Roll up the film.

[0005] Furthermore, the components of the outer layer, base layer and inner layer are as follows by mass ratio: outer layer 20%, base layer 60%; inner layer 20%.

[0006] Furthermore, the components of the outer layer are as follows by mass ratio: PP 58%, HDPE 14%, carbon black 3.5%, ammonium polyphosphate 17.5%, and dipentaerythritol 7%.

[0007] Furthermore, the components of the base layer are as follows by mass ratio: PP 78.8%, LDHs 16%, ammonium polyphosphate 2%, pentaerythritol 3%, and silane coupling agent 0.2%.

[0008] Furthermore, the components of the inner surface layer are as follows by mass ratio: PP 58%, HDPE 14%, carbon black 3.5%, ammonium polyphosphate 17.5%, and dipentaerythritol 7%.

[0009] The beneficial effects of the present invention are: Ammonium polyphosphate and dipentaerythritol in the outer layer will reduce the antistatic performance of the composite material, but adding HDPE as a dispersed phase controls the distribution of the conductive filler in the dispersed phase, thereby reducing the mutual influence between the flame retardant and the conductive filler, improving the antistatic efficiency of the conductive filler in the flame retardant antistatic polypropylene composite material, and providing space for improving the combustion performance and tensile properties of the composite material; the effect of the inner layer is the same as that of the outer layer; After the ammonium polyphosphate of the base layer is blended with LDHs, it is ball-milled with pentaerythritol and silane coupling agent to obtain intercalated coated modified LDHs. Ammonium polyphosphate and pentaerythritol form an expansion flame retardant system on the outside of LDHs, which promotes the production of carbon layer when the composite material is burned, and at the same time makes LDHs act more on the inside of the matrix under oxygen-free conditions, thereby improving the flame retardant performance. The addition of silane coupling agent improves the interface compatibility between the flame retardant and PP, so that the composite material maintains a high bending strength and notched impact strength. Implementation

[0010] In order to more intuitively and completely understand the technical solution of the present invention, a non-limiting feature description is now provided as follows: A method for producing a flame-retardant and antistatic CPP film, wherein the CPP film comprises an outer surface layer, a base layer and an inner surface layer; The outer layer is composed of PP, HDPE, carbon black, ammonium polyphosphate, and dipentaerythritol; The base layer is composed of PP, LDHs, ammonium polyphosphate, pentaerythritol and silane coupling agent; The inner surface layer is composed of PP, HDPE, carbon black, ammonium polyphosphate, and dipentaerythritol; The production method comprises the following steps: (1) The ammonium polyphosphate and dipentaerythritol of the outer layer are compounded into a halogen-free intumescent flame retardant, and then PP, HDPE and carbon black are added to blend together. The inner layer raw material blending method is the same as that of the outer layer; the ammonium polyphosphate of the base layer is blended with LDHs to form a powder, and then pentaerythritol and silane coupling agent are added to mix by ball milling, and finally PP is added to blend; (2) The raw materials of the outer layer, base layer and inner layer are fed into respective extruders for mixing and plasticizing; (3) The molten melts are fed into the die heads respectively, and the melts are combined in the die heads and then pass through the flat die head opening to form a molten sheet; (4) Using an air knife to attach the sheet to a chilled roller to quench it into an unshaped sheet, and then cooling it in a water bath to shape the sheet into a film; (5) Roll up the film.

[0011] The components of the outer layer, base layer and inner layer are in the following mass ratio: outer layer 20%, base layer 60%; inner layer 20%.

[0012] The components of the outer layer are as follows by mass ratio: PP 58%, HDPE 14%, carbon black 3.5%, ammonium polyphosphate 17.5%, and dipentaerythritol 7%.

[0013] The components of the base layer are as follows by mass ratio: PP 78.8%, LDHs 16%, ammonium polyphosphate 2%, pentaerythritol 3%, silane coupling agent 0.2%. The silane coupling agent is KH-550.

[0014] The components of the inner surface layer are as follows by mass ratio: PP 58%, HDPE 14%, carbon black 3.5%, ammonium polyphosphate 17.5%, and dipentaerythritol 7%.

[0015] Ammonium polyphosphate and dipentaerythritol in the outer layer will reduce the antistatic performance of the composite material, but adding HDPE as a dispersed phase controls the distribution of the conductive filler in the dispersed phase, thereby reducing the mutual influence between the flame retardant and the conductive filler, improving the antistatic efficiency of the conductive filler in the flame retardant antistatic polypropylene composite material, and providing space for improving the combustion performance and tensile properties of the composite material; the effect of the inner layer is the same as that of the outer layer; After the ammonium polyphosphate of the base layer is blended with LDHs, it is ball-milled with pentaerythritol and silane coupling agent to obtain intercalated coated modified LDHs. Ammonium polyphosphate and pentaerythritol form an expansion flame retardant system on the outside of LDHs, which promotes the production of carbon layer when the composite material is burned, and at the same time makes LDHs act more on the inside of the matrix under oxygen-free conditions, thereby improving the flame retardant performance. The addition of silane coupling agent improves the interface compatibility between the flame retardant and PP, so that the composite material maintains a high bending strength and notched impact strength.

Claims

1. A method for producing a flame retardant and antistatic CPP film, characterized in that: CPP film consists of an outer surface layer, a base layer and an inner surface layer; The outer layer is composed of PP, HDPE, carbon black, ammonium polyphosphate, and dipentaerythritol; The base layer is composed of PP, LDHs, ammonium polyphosphate, pentaerythritol and silane coupling agent; The inner surface layer is composed of PP, HDPE, carbon black, ammonium polyphosphate, and dipentaerythritol; The production method comprises the following steps: (1) The ammonium polyphosphate and dipentaerythritol of the outer layer are compounded into a halogen-free intumescent flame retardant, and then PP, HDPE and carbon black are added to blend together. The inner layer raw material blending method is the same as that of the outer layer; the ammonium polyphosphate of the base layer is blended with LDHs to form a powder, and then pentaerythritol and silane coupling agent are added to mix by ball milling, and finally PP is added to blend; (2) The raw materials of the outer layer, base layer and inner layer are fed into respective extruders for mixing and plasticizing; (3) The molten melts are fed into the die heads respectively, and the melts are combined in the die heads and then pass through the flat die head opening to form a molten sheet; (4) Using an air knife to attach the sheet to a chilled roller to quench it into an unshaped sheet, and then cooling it in a water bath to shape the sheet into a film; (5) Roll up the film.

2. The method for producing a flame retardant and antistatic CPP film according to claim 1, characterized in that: The components of the outer layer, base layer and inner layer are in the following mass ratio: outer layer 20%, base layer 60%; inner layer 20%.

3. The method for producing a flame retardant and antistatic CPP film according to claim 1, characterized in that: The components of the outer layer are as follows by mass ratio: PP 58%, HDPE 14%, carbon black 3.5%, ammonium polyphosphate 17.5%, and dipentaerythritol 7%.

4. The method for producing a flame retardant and antistatic CPP film according to claim 1, characterized in that: The components of the base layer are as follows by mass ratio: PP 78.8%, LDHs 16%, ammonium polyphosphate 2%, pentaerythritol 3%, and silane coupling agent 0.2%.

5. The method for producing a flame retardant and antistatic CPP film according to claim 1, characterized in that: The components of the inner surface layer are as follows by mass ratio: PP 58%, HDPE 14%, carbon black 3.5%, ammonium polyphosphate 17.5%, and dipentaerythritol 7%.