TWI849440B - Eco-friendly plastic composite flooring and its production method and application thereof - Google Patents

Abstract

A manufacturing formula for an environmentally friendly plastic floor tile includes: main plastic (low-polymerization PVC), recycled material, processing aid (ACR or SAN), impact agent (CPE), organic filler (natural fiber), inorganic filler (calcium carbonate), internal lubricant, external lubricant and thermal stabilizer; the environmentally friendly manufacturing formula for plastic floor tiles provided by the present invention will prevent natural fiber powder from being charred or pyrolyzed due to high temperature during the heating process, so that the natural material can be introduced into the composite material in large quantities, which can enable the composite material provided by the present invention to reduce the amount of PVC by a large amount of volume filling, but still maintain good product mechanical properties and improve the overall product dimensional stability.

Description

The manufacturing formula, processing method and application of environmentally friendly plastic floor tiles

The present invention relates to a composite material, in particular to an environmentally friendly plastic composite material containing a high amount of natural fiber addition.

The first application scope of the plastic composite material containing a high amount of natural fiber added provided by the present invention is plastic flooring, but the present invention is not limited to this single application, and other reasonably equivalent changes should be included in the scope claimed by the present invention.

Rice is widely produced in Asian countries, and rice husks and rice stalks are a rich source of natural materials. The two have similar compositions, but are usually regarded as agricultural waste and cannot be properly applied. It is rare to produce products with economic value. It is also a high cost expenditure to treat it as waste, and if it is burned, it may also cause problems such as air pollution. Therefore, how to recycle and reuse rice husks and rice stalks, and even how to expand this technology to all natural fiber materials, is a project that needs to be developed urgently.

In order to improve the existing problem that rice husks are regarded as agricultural waste with no economic value, and the waste treatment may also lead to environmental damage, the present invention provides an environmentally friendly composite material formula for plastic floor tiles, which includes: a main plastic (low-polymerization degree PVC) 24~27wt%; a recycled material: 14~2wt% of the scraps of its own products; a processing aid (ACR or S AN) 1.3~1.6wt%; an anti-impact agent (CPE) 0.9~1.4wt%; an organic filler (natural fiber) 15~25wt%; an inorganic filler (calcium carbonate) 29~35wt%; an internal lubricant 0.5~0.6wt%; an external lubricant 0.4~0.6wt%; and a thermal stabilizer 2.5~3wt%.

The natural fiber of the present invention is rice husk, with a particle size between 0.10 and 0.60 mm; the inorganic filler is calcium carbonate; the internal lubricant is a polar material of fatty acid esters; and the external lubricant is a non-polar material, including wax and polyethylene wax.

The present invention also provides a processing method for the environmentally friendly manufacturing formula of the plastic floor tile, the steps of which include: using a twin-screw extruder to set different mixing temperature sections, the mixing temperature section includes a feeding section, a plasticizing section, a compression section, an exhaust section and a metering section to mix the environmentally friendly manufacturing formula of the plastic floor tile at high temperature; and the twin-screw extruder The end of the extrusion die is connected to an extrusion die to mold the environmentally friendly manufacturing formula of the plastic floor tile obtained in the aforementioned mixing section. The extrusion die has an extrusion channel extending in the horizontal direction. The extrusion channel is set with multiple different molding temperature sections in the horizontal direction. The extrusion die processes the environmentally friendly manufacturing formula of the plastic floor tile into a flat sheet core material with a preset thickness.

Preferably, the extrusion die head includes the first molding section, the second molding section, the third molding section, the fourth molding section, the fifth molding section, the sixth molding section, the seventh molding section, the eighth molding section and the ninth molding section in the horizontal direction, and the nine molding sections are not completely the same in temperature and extrusion rate.

Among them, the temperature of the middle section of the extrusion die head will be lower than the temperature of the two sides, so that the extrusion speed of the middle section is slower than the extrusion speed of the two side sections, so as to maintain the same speed of the leading edge of the discharge.

Among them, the flat plate-shaped core material is further bonded with other functional materials. For example, a printed film with a pattern is hot-pressed, and a transparent thin sheet with long-term wear resistance is hot-pressed on it to simulate the production of surface decorative materials with wood grain, stone grain or woven grain and other simulated appearances, which are suitable for use as floor tiles.

Among them, the above-mentioned multi-layered surface decoration materials are further coated with acrylic coatings, cured by ultraviolet light and then processed in the later stage.

Furthermore, the present invention finally provides the application of the aforementioned environmentally friendly manufacturing formula for plastic floor tiles.

In summary of the above description, the present invention has the following beneficial effects and functions:

1. The low-polymerization PVC (such as Formosa Plastics' S-57 with a polymerization degree of 620±30 or S-58 with a polymerization degree of 700±30) in the environmentally friendly manufacturing formula of the plastic floor tiles provided by the present invention has excellent gelatinization and extremely high transparency, and because of its small molecular weight, it can reduce the overall processing temperature, which will prevent the natural fiber from being charred or pyrolyzed due to high temperature during the heating process, so that the natural material can be introduced into the composite material in large quantities. The composite material provided by the present invention can greatly fill the volume to reduce the amount of PVC, but still maintains good product mechanical properties and improves the overall product dimensional stability, and is also about 20% lighter than ordinary pure stone plastic floor tiles. The particle size of the natural fiber is preferably in the range of 0.10~0.60mm to achieve better hardness, toughness and wood-like texture in the final product.

2. The formula of this invention can also add the scraps of its own products as recycled materials, which not only makes the formula of this invention more environmentally friendly, but also makes the mixing and plasticizing process faster and smoother.

The present invention also provides a composite core board made from the environmentally friendly manufacturing formula of the plastic floor tile disclosed herein. The natural fiber composite core board is covered with a PVC printed film and a transparent PVC wear-resistant layer on the top to make a decorative panel, which is applied to floors or walls. The bottom of the floor can also be matched with a foamed sound insulation layer to provide impact resistance and sound insulation improvement effect.

10: Twin screw extruder

11: Feeding section

12: Plasticizing section

13: Compression section

14: Exhaust section

15: Metering section

16: Converging core section

20: Extrusion die head

21: First molding section

22: Second molding section

23: The third molding section

24: The fourth molding section

25: The fifth molding section

26: Sixth molding section

27: Seventh molding section

28: The eighth molding section

29: Ninth forming section

30: Plastic flooring

31: Wear-resistant layer

32: Printing layer

33: Core board

34: Foam sound insulation layer

Figure 1 is a schematic diagram of the twin-screw extruder 10 and die head 20 used in the processing of the environmentally friendly plastic floor tiles of the present invention.

Figure 2 is a schematic diagram of a floor made using the manufacturing formula of the environmentally friendly plastic floor tiles of the present invention.

The advantages and features of the present invention and the methods of achieving them will be described in more detail with reference to the exemplary embodiments and drawings so as to be more easily understood. However, the present invention may be implemented in different forms and should not be understood to be limited to the embodiments described herein. On the contrary, for those with ordinary knowledge in the art, the embodiments provided will make the present invention more transparent and comprehensive and fully convey the scope of the present invention, and the present invention will be defined only by the scope of the attached patent application. In the figures, the dimensions and relative dimensions of the components or assemblies are expressed in an exaggerated manner for clarity. Throughout the specification, the same component symbols refer to the same components. As used hereinafter, the term "and/or" includes any and all combinations of one or more of the related listed objects.

The following will describe the exemplary embodiments in detail with the accompanying drawings. However, these embodiments may be included in different forms and should not be interpreted as limiting the scope of the patent application of the present invention. These embodiments are provided to make the disclosure of the present invention complete and clear, and people familiar with this technology will be able to understand the scope of the present invention through these embodiments.

The present invention provides an environmentally friendly manufacturing formula for plastic floor tiles, which includes: a main plastic: low-polymerization degree polyvinyl chloride (PVC, such as Formosa Plastics' S-57 with a polymerization degree of 620±30 or S-58 with a polymerization degree of 700±30) 24~27wt%; a recycled material: 14~21wt% of the scraps of its own products; a processing aid: polyacrylate (ACR) or styrene-acrylonitrile copolymer (SAN) 1.3 ~1.6wt%; an anti-impact agent: chlorinated polyethylene (CPE) 0.9~1.4wt%; an organic filler: natural fiber 15~25wt%; an inorganic filler: calcium carbonate 29~35wt%; an internal lubricant: fatty acid ester 0.5~0.6wt%; an external lubricant: polyethylene wax 0.4~0.6wt%; and a thermal stabilizer: calcium zinc composite stabilizer 2.5~3wt%.

The preferred embodiment of the natural fiber powder particle size is in the range of 0.10-0.60 mm, so as to exhibit better hardness, toughness and wood-like texture in the final product. In addition, the low-polymerization-degree PVC in the formula (such as Formosa Plastics' S-57 with a polymerization degree of 620±30 or S-58 with a polymerization degree of 700±30) has excellent gelatinization and extremely high transparency, and because of its relatively small molecular weight (approximately 37,500~45,000g/mol), it can reduce the overall processing temperature of the process and prevent the natural fiber powder from being charred or pyrolyzed due to high temperatures during the heating process, thereby achieving the purpose of being able to add a high content of natural fiber powder; ingredients such as polyacrylate (ACR)/styrene-acrylonitrile copolymer (SAN) and chlorinated polyethylene (CPE) can promote the gelatinization and mixing performance of the formula, provide toughness and impact resistance, and the overall formula of the present invention enables the natural material to be introduced into the composite material at a higher ratio. The composite material provided by the present invention can significantly fill the volume to reduce the amount of PVC used, but still maintains good product mechanical properties and improves the overall product dimensional stability, and also reduces the weight by about 20% compared to general pure stone plastic flooring.

Further, please refer to Figure 1. The environmentally friendly manufacturing formula of the plastic floor tiles provided by the present invention can still be applied to the extrusion process and manufacture related board materials at a high proportion of natural fiber and inorganic filler addition. The processing steps basically include:

Step S1) Mixing section: Using a twin-screw extruder 10, such as a tapered twin-screw extruder, different mixing temperature sections are set, and the mixing temperature section includes a feeding section (Feed zone) 11, a plasticizing section (Plasticizing zone) 12 and a compression section (Compression zone) 13, a venting section (Vent zone) 14 and a metering section (Metering zone) 15. The aforementioned environmentally friendly manufacturing formula of the plastic floor tile is first mixed by high-speed stirring and cooled by low-speed stirring, and then heated and kneaded by the twin-screw extruder 10. Alternatively, the mixed formula melt can be gathered to a confluence core section 16 after the metering section 15 to be compressed and compacted again and enter the subsequent step 2.

Specifically, step S1 may be to firstly weigh the raw materials of the aforementioned environmentally friendly manufacturing formula of the plastic floor tile according to the formula, feed the materials into a high-speed mixer and stir and mix them at 1000 rpm for 5 minutes, pay attention to maintaining the temperature not exceeding 135°C during mixing, discharge the uniformly mixed materials (usually powdered materials) into a low-speed mixer and stir at a low speed to reduce the material temperature to below 45°C, and then transport them to a hopper connected to the aforementioned feeding section 11 for preparation. Feeding, pre-set the appropriate processing temperature (140~160℃) for the different processing sections of the conical twin-screw extruder and the confluence core section 16 connected at the end, and start feeding when the temperature reaches the set temperature. The evenly mixed environmentally friendly manufacturing formula of the plastic floor tile passes through the feeding, plasticizing, compression, exhaust, and metering zone heating treatment described in the aforementioned step S1, and finally converges to the confluence core section 16 to the extrusion die head of the subsequent step 2.

Step 2) Molding section: The end of the twin-screw extruder 10 is connected to the extrusion die (such as a T-die) 20 to mold the environmentally friendly manufacturing formula of the plastic floor tile obtained in the mixing section. The extrusion die 20 has a fan-shaped extrusion channel extending in the horizontal direction. The extrusion channel is set with several different molding temperature sections in the horizontal direction (or transverse direction). In a preferred embodiment, the extrusion die 20 is divided into nine heating sections. The segments are used to control the fluidity of the melt, and the uniformity of the flow rate is adjusted with the adjusting rod. As shown in FIG. 1 , from left to right, the first molding segment 21, the second molding segment 22, the third molding segment 23, the fourth molding segment 24, the fifth molding segment 25, the sixth molding segment 26, the seventh molding segment 27, the eighth molding segment 28 and the ninth molding segment 29 are included. The extrusion die 20 processes the environmentally friendly manufacturing formula of the plastic floor tile into a flat plate-shaped core material with a preset thickness. Preferably, the aforementioned nine molding sections have different temperatures and extrusion speeds. Usually, the temperature of the portion close to the middle section (e.g., the fourth molding section 24, the fifth molding section 25, and the sixth molding section 26) is slightly lower than the temperature of the two side sections (e.g., the first molding section 21, the second molding section 22, and the third molding section 23 on the left side and the seventh molding section 27, the eighth molding section 28, and the ninth molding section 29 on the right side). At the same time, the extrusion speed of the middle section is slightly slower than the extrusion speed of the two side sections, so that a flat plate-shaped core material can be produced.

Step 3) (optional) Production of finished/semi-finished products: The extruded flat core material can be heat-bonded with a PVC printed film and a transparent PVC wear-resistant layer on the top on the same production line to make a decorative panel for use in floors or walls. The bottom of the floor can also be equipped with a foamed sound insulation layer to provide impact resistance and sound insulation improvement.

Taking floor production as an example, please refer to Figure 2, which is a plastic floor 30 made by the sheet material produced by the aforementioned embodiment of the present invention and stacked with other functional layers, which sequentially includes: a wear-resistant layer 31, which is a transparent polyvinyl chloride sheet material; a printing layer 32, which is an ink printing layer for decoration; a composite core board 33, which is a board sheet material made by the aforementioned environmentally friendly manufacturing formula of the plastic floor tile; and a foam sound insulation layer 34.

The steps of making the plastic floor 30 include first putting the sheet rolls of the printing layer 32 and the wear-resistant layer 31 on the rack, and the composite core board 33 is a continuously discharged extruded sheet. The printing layer 32 and the wear-resistant layer 31 are pressed and laminated on the core board 33 with excess heat through the traction wheel and the laminating wheel. According to the product requirements, the surface temperature can be optionally increased through the baking heating zone, and the corresponding simulated embossing is pressed on the surface of the laminated composite board by the embossing wheel. The semi-finished product with film lamination and embossing is continuously extended to the rear section for pushing and cooling. When the temperature drops below 40°C, it is cut into large pieces and stacked for storage, waiting for other post-processing processes.

Step 4) (optional) Post-processing: After cooling to room temperature, the large semi-finished product is first coated with acrylic coating on the surface, and cured by ultraviolet light to provide the surface with enhanced scratch resistance. Then the large semi-finished product is sliced into required specifications and sizes by multi-blade saws, and then the four sides are cut into tenons by a locking machine. IXPE foam pads are attached to the bottom to provide impact resistance and sound insulation and eliminate the unevenness of the ground. Finally, the finished product is packaged and shipped. The overall thickness of the plastic floor is 5.5~7.0mm, the thickness of the wear-resistant layer is 0.30~0.55mm, and the thickness of the foam sound insulation layer is 1.0~1.5mm.

The roles of the internal lubricant and the external lubricant in the formula proposed by the present invention are that the internal lubricant reduces the friction between the PVC molecular chains, thereby reducing the melt viscosity. The internal lubricant is a polar polybasic fatty acid ester, such as linolenic acid ester, octadecatetraenoic acid ester or arachidonic acid ester derivative, etc., which is highly compatible with PVC. The external lubricant reduces the adhesion between PVC and the metal surface of the processing machine. The external lubricant is mainly non-polar, such as polyethylene wax. Most importantly, by using low-polymerization PVC (such as Formosa Plastics' S-57 with a polymerization degree of 620±30 or S-58 with a polymerization degree of 700±30), the present invention can reduce the processing temperature of the plastic melt by at least 50°C compared to the existing PVC formulations in the industry, effectively reducing energy consumption and preventing natural fiber powder from scorching or pyrolyzing due to high temperatures during the heating process.

<Example 1> As shown in Table 1, the formula ratio of no recycled materials:

Please refer to Table 2 below, which shows the formula ratio of recycled materials, including low-polymerization polyvinyl chloride (such as Formosa Plastics' S-57 with a polymerization degree of 620±30 or S-58 with a polymerization degree of 700±30), recycled materials, polyacrylate resin (ACR), chlorinated polyethylene (CPE), natural fiber (rice husk) powder, inorganic filler, internal lubricant, external lubricant, stabilizer and other ingredients. According to the ratios of Examples 2 to 5, finished products with different effects are completed. Among them, the recycled materials include the crushed scraps of the own products, the inorganic filler is preferably calcium carbonate powder, and the natural fiber powder is preferably rice husk powder.

<Process parameters>

Step 1: Twin-screw extruder temperature setting: Use a conical twin-screw extruder to mix the environmentally friendly manufacturing formula of the plastic floor tile that has been stirred and mixed evenly. The heating zone of the conical twin-screw extruder is preferably divided into 5 sections and a possible final confluence core section. The temperature of each zone is as shown in the following table. After the equipment reaches the set temperature, the material is fed for production. The main machine speed of the twin-screw extruder is about 10rpm, the current is about 150~180A, and the melt pressure is about 1.6~2.0MPa. The subsequent extrusion die head 20 extrudes the sheet material at a rate of about 800kg/hour.

Step 2: The extrusion die head 20 is divided into 9 sections, each section has a temperature of about 160~190℃, and the speed of each section may be different. It can mainly control the thickness of the core board sheet and the stability of the discharge to achieve a smooth product performance.

The performance of the first embodiment of the floor tile 30 is as follows:

The invention provides a core board made from the aforementioned environmentally friendly manufacturing formula of plastic floor tiles. The natural fiber composite core board can be hot-stamped on the same production line with a PVC printed film and a transparent PVC wear-resistant layer on the top to make a decorative panel, which can be used for floors or wall panels. The bottom of the floor can also be equipped with a foamed sound insulation layer to provide impact resistance and sound insulation improvement.

The above is only a preferred embodiment of the present invention and is not intended to limit the present invention. For technicians in this field, the present invention may have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present invention shall be included in the scope of protection of the present invention.

10: Twin screw extruder

11: Feeding section

12: Plasticizing section

13: Compression section

14: Exhaust section

15: Metering section

16: Converging core section

20: Extrusion die head

Claims (9)

An environmentally friendly manufacturing formula for plastic floor tiles, comprising: 24-27wt% of low-polymerization degree polyvinyl chloride (PVC, such as S-57 or S-58 produced by Formosa Plastics); 14-21% of recycled materials, such as crushed materials such as semi-finished products, defective products, and stagnant materials of recycled PVC composite floor tiles; and 1.3-1.6wt% of processing aids, such as polyacrylate (ACR) or styrene-acrylonitrile copolymer (SAN). wt%; an anti-impact agent: chlorinated polyethylene (CPE) 0.9~1.4wt%; an organic filler: natural fiber 15~25wt%; an inorganic filler: calcium carbonate 29~35wt%; an internal lubricant: fatty acid ester 0.5~0.6wt%; an external lubricant: polyethylene wax 0.4~0.6wt%; and a thermal stabilizer: calcium-zinc composite stabilizer 2.5~3wt%. The environmentally friendly manufacturing formula of plastic floor tiles as described in claim 1, wherein: the natural fiber is rice husk, for example, with a particle size between 0.10 and 0.60 mm; the inorganic filler is calcium carbonate, talcum powder or a mixture thereof; the internal lubricant is a polar polybasic fatty acid ester; the external lubricant is a non-polar material, including polyethylene wax. A processing method for an environmentally friendly manufacturing formula of plastic floor tiles, the steps of which include: providing the environmentally friendly manufacturing formula of plastic floor tiles as described in claim 1 or 2; using a twin-screw extruder to set different mixing temperature sections, the mixing temperature section including a feeding section, a plasticizing section and a compression section, an exhaust section and a metering section to perform high-temperature mixing of the environmentally friendly manufacturing formula of plastic floor tiles; and the aforementioned The end of the twin-screw extruder is connected to an extrusion die to mold the environmentally friendly manufacturing formula of the plastic floor tile obtained in the aforementioned mixing section. The extrusion die has an extrusion channel extending in the horizontal direction. The extrusion channel is set with multiple different molding temperature sections in the horizontal direction. The extrusion die processes the environmentally friendly manufacturing formula of the plastic floor tile into a flat sheet core material with a preset thickness. As described in claim 3, the processing method of the environmentally friendly manufacturing formula of plastic floor tiles, the extrusion die head includes the first molding section, the second molding section, the third molding section, the fourth molding section, the fifth molding section, the sixth molding section, the seventh molding section, the eighth molding section and the ninth molding section in the horizontal direction, and the nine molding sections are different in temperature and extrusion rate. The processing method of the environmentally friendly manufacturing formula of plastic floor tiles as described in claim 3 or 4, wherein the temperature of the extrusion die head near the middle section is lower than the temperature of the two side sections, and the extrusion speed of the middle section is slower than the extrusion speed of the two side sections. The processing method of the environmentally friendly manufacturing formula of plastic floor tiles as described in claim 3 or 4, wherein the flat film sheet is further bonded to other functional materials. As described in claim 6, the processing method of the environmentally friendly manufacturing formula of plastic floor tiles, wherein the above-mentioned multi-layered surface decoration material is further coated with acrylic coating, cured by ultraviolet light and then processed in the later stage. A plastic floor, comprising: a wear-resistant layer, which is a transparent polyvinyl chloride sheet; a printing layer, which is an ink printing layer for decoration; a composite core board, which is a board made from the environmentally friendly manufacturing formula of plastic floor tiles as described in claim 1 or 2; and a sound insulation layer, which is an IXPE foam pad. As for the plastic floor described in claim 8, the overall thickness of the plastic floor is 5.5~70mm, the thickness of the wear-resistant layer is 0.3~0.55mm, and the thickness of the foamed sound insulation layer is 1.0~1.5mm.

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