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EP-4023714-B1 - POLYPROPYLENE PLATE AND PREPARATION METHOD THEREFOR

EP4023714B1EP 4023714 B1EP4023714 B1EP 4023714B1EP-4023714-B1

Inventors

  • ZHANG, XIAOLING
  • XIAO, Zhiyuan
  • LI, YANHUI

Dates

Publication Date
20260506
Application Date
20211105

Claims (6)

  1. A method for preparing a polypropylene board, comprising: subjecting a mixture of a modified polypropylene resin, a filler, an acrylic acid and a lubricant to extrusion molding to prepare the polypropylene board; wherein the mixture comprises 25-40 parts by weight of the modified polypropylene resin, 30-70 parts by weight of the filler, 3-10 parts by weight of the acrylic acid and 1-8 parts by weight of the lubricant; the modified polypropylene resin is selected from the group consisting of a polyolefin-modified polypropylene resin, an acrylic acid-grafted polypropylene resin and a combination thereof; and a melt flow rate of the modified polypropylene resin is 2-9 g/10 min as measured in accordance with ISO 1133-1:2011 at 230 °C under a nominal load of 2.16 kg; and the method for preparing the polypropylene board does not involve a plasticizer, an antioxidant, a vulcanizer and a colorant.
  2. The method according to claim 1, characterized in that the mixture comprises 30-36 parts by weight of the modified polypropylene resin, 30-70 parts by weight of the filler, 5-8 parts by weight of the acrylic acid and 2-5 parts by weight of the lubricant.
  3. The method according to claim 1, characterized in that the filler is selected from the group consisting of calcium carbonate, kaolin, and a combination thereof; and a fineness of the filler is 400-800 mesh.
  4. The method according to claim 1, characterized in that the lubricant is selected from the group consisting of zinc fatty acid, polyethylene wax and a combination thereof.
  5. The method according to claim 1, further comprising: before the extrusion molding, subjecting the modified polypropylene resin, the filler, the acrylic acid and the lubricant to blending and kneading to obtain the mixture; wherein a kneading temperature is 70-80°C, and a kneading time is more than 60 s; and the extrusion molding is performed at 190-200°C.
  6. The method according to claim 5, further comprising: after the extrusion molding, subjecting a polypropylene substrate obtained from the extrusion molding to lamination, cooling and quenching; wherein the lamination is performed by laminating a polypropylene color film and a polypropylene wear-resistant layer on the polypropylene substrate to obtain the polypropylene board with the polypropylene color film, the polypropylene wear-resistant layer and the polypropylene substrate arranged successively.

Description

TECHNICAL FIELD This disclosure relates to the manufacturing of floors, and more particularly to a polypropylene board and a method for preparing the same. BACKGROUND The polyvinyl chloride (PVC) floor, also known as "light-weight floor material", has been widely used in the floor decoration. In the preparation of the PVC floor, PVC and co-polymer resins thereof used as main raw materials are compounded with auxiliary materials, such as fillers, plasticizers, stabilizers, and colorants, and then subjected to coating, calendering, or extrusion on a continuous sheet substrate to prepare the PVC floor. Unfortunately, the exiting PVC floor cannot meet the requirements of environmental protection due to the volatilization of toxic gases and the presence of plasticizers. Therefore, it is of great significance to develop a floor material free of PVC and plasticizers. Polypropylene (PP) materials are readily available, and have low cost and good gloss. Moreover, the PP materials are free of toxicity and peculiar smell. However, the existing PP board cannot be fully mixed with the fillers such that the extrusion molding cannot be smoothly completed and the product is prone to delamination, which restricts the large-scale production and application of the PP board. SUMMARY An object of the present disclosure is to provide a polypropylene board and a method for preparing the same to smoothly complete the extrusion molding of polypropylene boards in the absence of a plasticizer. The invention is set out in the appended set of claims. This disclosure provides a method for preparing the polypropylene board, comprising: subjecting a mixture of a modified polypropylene resin, a filler, an acrylic acid and a lubricant to extrusion molding to prepare the polypropylene board; wherein the mixture comprises 25-40 parts by weight of the modified polypropylene resin, 30-70 parts by weight of the filler, 3-10 parts by weight of the acrylic acid and 1-8 parts by weight of the lubricant; the modified polypropylene resin is selected from the group consisting of a polyolefin-modified polypropylene resin, an acrylic acid-grafted polypropylene resin and a combination thereof; and a melt flow rate of the modified polypropylene resin is 2-9 g/10 min as measured in accordance with ISO 1133-1:2011 at 230 °C under a nominal load of 2.16 kg; and the method for preparing the polypropylene board does not involve a plasticizer, an antioxidant, a vulcanizer and a colorant. In an embodiment, the mixture comprises 30-36 parts by weight of the modified polypropylene resin, 30-70 parts by weight of the filler, 5-8 parts by weight of the acrylic acid and 2-5 parts by weight of the lubricant. In an embodiment, the filler is selected from the group consisting of calcium carbonate, kaolin, and a combination thereof; and a fineness of the filler is 400-800 mesh. In an embodiment, the lubricant is selected from the group consisting of zinc fatty acid, polyethylene wax and a combination thereof. In an embodiment, the method further comprises: before the extrusion molding, subjecting the modified polypropylene resin, the filler, the acrylic acid and the lubricant to blending and kneading to obtain the mixture of the raw materials;wherein a kneading temperature is 70-80°C, and a kneading time is more than 60 s; and the extrusion molding is performed at 190-200°C. In an embodiment, the method further comprises: after the extrusion molding, subjecting an extrusion molded product sequentially to lamination, cooling and quenching;wherein the lamination is performed by laminating a polypropylene color film and a polypropylene wear-resistant layer on the extrusion molded product to obtain the polypropylene board with the polypropylene color film, the polypropylene wear-resistant layer and a polypropylene substrate arranged successively. In an embodiment, a thickness of the polypropylene board is 5-6 mm; a thickness of the polypropylene substrate is 4-8 mm, preferably 4-6 mm; a thickness of the polypropylene color film is 0.02-0.08 mm, preferably 0.06-0.08 mm; a thickness of the polypropylene wear-resistant layer is 0.15-0.8 mm, preferably 0.35-0.55 mm; and the polypropylene wear-resistant layer has a haze less than 10% and a light transmittance larger than 92%. The beneficial effects of the present disclosure are described below. With respect to the polypropylene board provided herein, the raw material composition is optimized by introducing a modified polypropylene resin with a melt flow rate of 2-9 g/10 min, a filler, a stabilizer, and a lubricant. Moreover, the amount of individual raw materials is regulated such that the polypropylene board can be fabricated by extrusion molding in the absence of a plasticizer, and the delamination will not occur. In the method provided herein for preparing the polypropylene board, the raw material formula is optimized such that the polypropylene board can be fabricated by extrusion molding in the absence of a plasticizer, and