Plastic flooring substrate prepared from recycled pet

Abstract

The present invention relates to the technical field of floorings, and discloses a plastic flooring substrate prepared from recycled PET. The substrate is prepared by mixing a recycled PET material, a stone powder, a chain extender, stearic acid, an oil body and an elastomer. In terms of mass percentage, the recycled PET material accounts for 15% to 25%; the stone powder accounts for 65% to 78%; the chain extender accounts for 0.4% to 1%; the stearic acid accounts for 0.5% to 2%; the oil body accounts for 1% to 3%; and the elastomer accounts for 1% to 5%. The recycled PET is used as a binder to bind the stone powder, and the mixture is extruded by means of an extruder to form a substrate for plastic floorings; products having GRS and SCS certifications can be readily obtained, and a PET product, unlike conventional PVC plastic flooring substrates, does not decompose upon exposure to light to release irritating chlorine gas or hydrogen chloride; furthermore, since recycled PET is widely available, the products have a broader market.

Description

A plastic flooring substrate made from recycled PET Technical Field

[0001] This invention relates to the field of flooring technology, and more specifically to a plastic flooring substrate made from recycled PET. Background Technology

[0002] Currently, the main materials used in plastic flooring are PVC (Polyvinyl Chloride) and stone powder. However, PVC is easily decomposed when exposed to light and heat, releasing irritating gases such as chlorine and hydrogen chloride, which can irritate the respiratory tract and affect human health. Newer plastic flooring, for environmental reasons, commonly uses non-toxic virgin materials such as PETG (Polyethylene Terephthalate Glycol), TPU (Thermoplastic Polyurethane), and PP (Polypropylene). However, with increasing environmental awareness, European and American countries are more willing to accept products made from recycled materials to protect their increasingly damaged environment. Products with GRS (Global Recycled Standard) and SCS (SCS Global Services Certification) certifications have a broader market than products made from conventional virgin materials. Recycled PET has a wide range of sources; common beverage bottles and waste textiles from clothing manufacturing are inexpensive recycled PET sources. Therefore, we plan to develop a plastic flooring substrate made from recycled PET. Summary of the Invention

[0003] Purpose of the invention: The technical problem to be solved by the present invention is to provide a plastic flooring substrate made of recycled PET (Polyethylene Terephthalate), which solves the problem that existing waste PET cannot be recycled and reused. Technical solution

[0004] To solve the above problems, the technical solution provided by the present invention is as follows:

[0005] A plastic flooring substrate made from recycled PET, wherein the substrate is prepared by mixing recycled PET material, stone powder, chain extender, stearic acid, oil, and elastomer, wherein, by mass percentage, the recycled PET material accounts for 15% to 25%, the stone powder accounts for 65% to 78%, the chain extender accounts for 0.4% to 1%, the stearic acid accounts for 0.5% to 2%, the oil accounts for 1% to 3%, and the elastomer accounts for 1% to 5%.

[0006] Furthermore, by mass percentage, the recycled PET material is required to have a crushed material sludge or silica content of ≤0.5% and a moisture content of ≤0.3%.

[0007] Furthermore, the calcium carbonate powder has a particle size of 300-400 mesh.

[0008] Furthermore, the stearic acid is required to have a molecular weight ≤300.

[0009] Furthermore, the oil is industrial-grade white oil, with a grade between 5# and 68#.

[0010] Furthermore, the elastomer is nitrile rubber, with a molecular weight of 650,000-750,000 and a particle size of approximately 0.8 mm.

[0011] Furthermore, by mass percentage, the recycled PET material accounts for 20%, the stone powder accounts for 75%, the chain extender accounts for 1%, the stearic acid accounts for 1%, the oil body accounts for 1%, and the elastomer accounts for 2%.

[0012] Further, by mass percentage, the recycled PET material accounts for 20%, the stone powder accounts for 73%, the chain extender accounts for 1.5%, the stearic acid accounts for 1.5%, the oil body accounts for 1.5%, and the elastomer accounts for 2.5%.

[0013] A method for producing a plastic flooring substrate made from recycled PET involves mixing the materials in a certain proportion, granulating the mixture in equipment, feeding the substrate granules into an extruder, and extruding the substrate through the extruder.

[0014] Furthermore, the substrate particles are no longer than 3 mm and have a diameter of less than 2 mm. Beneficial effects

[0015] Compared with the prior art, the technical solution provided by this invention has the following advantages:

[0016] Using recycled PET as an adhesive to bond stone powder, the material is extruded and molded to form the base material for PVC flooring. This makes it very easy to obtain GRS and SCS certifications. At the same time, PET products do not decompose into chlorine and hydrogen chloride with an irritating odor when exposed to light, unlike conventional PVC flooring base materials. Furthermore, because recycled PET materials are more readily available, they have a broader market. Attached Figure Description

[0017] Figure 1 is a schematic diagram of the process flow of Embodiment 1 of the present invention. Detailed Implementation

[0018] To make the technical solution of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Example

[0019] Referring to Figure 1, a type of plastic flooring substrate made from recycled PET uses recycled PET as an adhesive to bond stone powder, which can meet environmental protection requirements. At the same time, the sources of recycled PET are very wide, such as common beverage bottles and waste textiles from clothing, which are inexpensive recycled PET and can greatly save costs.

[0020] The flooring substrate is made from a mixture of recycled PET material, stone powder, chain extender, stearic acid, oil, and elastomer. The following proportions are by weight percentage.

[0021] Firstly, recycled PET material accounts for 15% to 25%. This recycled PET material comes from various beverage bottles without caps. The caps are made of PE and are therefore unusable. The beverage bottles must be crushed and cleaned, requiring the crushed material to have a sand or silica content ≤0.5% and a moisture content ≤0.3%. This recycled material is then used as an adhesive in the product.

[0022] Calcium carbonate powder of any size with a particle size of 300-400 mesh and a stone powder content of 65% to 78% is used as a filler, with a moisture content of ≤0.1%.

[0023] The chain extender accounts for 0.4% to 1% and is used as a chain extender for PET to prevent hydrolysis during PET processing. The preferred grade is Joncryl ADR 4468.

[0024] Stearic acid accounts for 0.5% to 2% and mainly plays an internal lubricating role. It is required that the molecular weight is ≤300, and the preferred grade is SA1841.

[0025] The oil content is 1% to 3%, mainly used for external lubrication and for demolding of the substrate. Industrial grade white oil can be used, and the grade can be selected between 5# and 68#, with industrial lubricating white oil 10# being preferred.

[0026] The elastomer accounts for 1% to 5%, and nitrile rubber is used as the elastomer to enhance the toughness of the substrate. The molecular weight of nitrile rubber is 650,000 to 750,000, and the particle size is about ≤0.8mm. The preferred grade is maleic anhydride grafted POE-G-GMA elastomer CH-904.

[0027] 2. Process flow:

[0028] First, the above materials are mixed in proportion, and then put into the equipment for granulation. Then, the substrate particles are put into the extruder and the substrate is extruded through the extruder.

[0029] Granulation process: The raw materials are added to the high-speed mixer in proportion and in no particular order. The materials generate heat to 90°C through stirring and friction. The discharge port is automatically opened and the materials are cooled to 40°C in a low-speed mixer before use.

[0030] The mixed material is fed into a 60-type parallel twin-screw granulator extruder for extrusion. The screw temperature is set from high to low, from 320 to 280℃. After extrusion, the material is cut into particles with a length of ≤3mm and a diameter of less than 2mm.

[0031] Extruder core technology:

[0032] Extrusion was performed using a standard 110-type parallel twin-screw extruder. The screw temperature was set from high to low, from 320 to 280℃, the extrusion die temperature was set from 280 to 290℃, and the temperature of each forming roller was set to 190℃.

[0033] Recycled PET is used as an adhesive to bond stone powder, which is then extruded to form the base material for PVC flooring. When the base material thickness is ≥4mm, the product performance meets the following requirements:

[0034] 1. According to GB / T 11718-2009 and GB / T 17657-2013, the average static bending strength is ≥18 MPa, the average elastic modulus is ≥3000 MPa, and the average deformation at the point of maximum force is ≥3 mm.

[0035] 2. After slotting, the product shall be tested in accordance with ISO 10582-2017 and ISO 24334-2019 to ensure that the locking tension is ≥15kgf / 50mm.

[0036] The substrate was tested according to EN 13329:2016+A2:2021, with a drop ball impact height ≥1200mm.

[0037] Better Example 1:

[0038] The formula used is as follows:

[0039] Raw material composition: 20% recycled PET flakes (moisture content ≤0.3%), 75% white stone powder (350 mesh), 81% chain extender (Joncryl ADR 446), 11% stearic acid (SA184), 1% industrial lubricating white oil (10#), and 42% elastomer (maleic anhydride grafted POE-G-GMA elastomer CH-90).

[0040] Add each raw material to the high-speed mixer in the order listed in the table above. The material will generate heat to 90°C through friction during mixing. The discharge port will be automatically opened and the material will be cooled to 40°C in a low-speed mixer. The raw material will then be removed and fed into a 60-type flat twin-screw granulator extruder. The screw temperature will be set from high to low, from 320 to 280°C. After extrusion, the material will be cut into particles with a length of ≤3mm and a diameter of less than 2mm.

[0041] The granulated material was extruded using a standard 110-type flat twin-screw extruder. The screw temperature was set from high to low, from 320-280℃, the extrusion die temperature was set from 280-290℃, and the temperature of each forming roller was set to 190℃. The final extruded material was a qualified substrate measuring 1000mm*1600mm*5.0mm.

[0042] The substrate was tested and found to have an average static bending strength of 32 MPa, an average elastic modulus of 3800 MPa, and an average deformation at the point of maximum force of 4.0 mm, which meets the requirements.

[0043] Better Example 2:

[0044] The formula used is as follows:

[0045] Raw material composition: Recycled PET material (moisture content ≤0.3%), 20% crushed and recycled colored bottle flakes, 73% white stone powder (350 mesh), 1.5% chain extender (Joncryl ADR 4468), 1.5% stearic acid (SA184), 1.5% industrial lubricating white oil 10#, 1.5% elastomer (maleic anhydride grafted POE-G-GMA elastomer CH-904), 2.5% elastomer.

[0046] Add each raw material to the high-speed mixer in the order listed in the table above. The material will generate heat to 90°C through friction during mixing. The discharge port will be automatically opened and the material will be cooled to 40°C in a low-speed mixer. The raw material will then be removed and fed into a 60-type flat twin-screw granulator extruder. The screw temperature will be set from high to low, from 320 to 280°C. After extrusion, the material will be cut into particles with a length of ≤3mm and a diameter of less than 2mm.

[0047] The granulated material was extruded using a standard 110-type flat twin-screw extruder. The screw temperature was set from high to low, from 320-280℃, the extrusion die temperature was set from 280-290℃, and the temperature of each forming roller was set to 190℃. The final extruded material was a qualified substrate measuring 1000mm*1600mm*5.5mm.

[0048] The substrate was tested and found to have an average static bending strength of 28 MPa, an average elastic modulus of 4350 MPa, and an average deformation at the point of maximum force of 4.3 mm, which meets the requirements.

[0049] Unless otherwise specified, all proportions in this invention are mass proportions, and all percentages in this invention are mass percentages.

[0050] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of this patent should be determined by the appended claims.

Claims

1. A plastic flooring substrate made from recycled PET, characterized in that, The substrate is prepared by mixing recycled PET material, stone powder, chain extender, stearic acid, oil, and elastomer. By mass percentage, the recycled PET material accounts for 15% to 25%, the stone powder accounts for 65% to 78%, the chain extender accounts for 0.4% to 1%, the stearic acid accounts for 0.5% to 2%, the oil accounts for 1% to 3%, and the elastomer accounts for 1% to 5%.

2. The plastic flooring substrate made from recycled PET according to claim 1, characterized in that, The recycled PET material, by mass percentage, requires that the content of crushed mud or silica be ≤0.5% and the moisture content be ≤0.3%.

3. A plastic flooring substrate made from recycled PET according to claim 1, characterized in that, The calcium carbonate powder has a particle size of 300-400 mesh.

4. A plastic flooring substrate made from recycled PET according to claim 1, characterized in that, The stearic acid is required to have a molecular weight ≤300.

5. A plastic flooring substrate made from recycled PET according to claim 1, characterized in that, The oil is industrial-grade white oil, with a grade between 5# and 68#.

6. A plastic flooring substrate made from recycled PET according to claim 1, characterized in that, The elastomer is nitrile rubber, with a molecular weight of 650,000-750,000 and a particle size of approximately 0.8 mm.

7. A plastic flooring substrate made from recycled PET according to claim 1, characterized in that, By mass percentage, the recycled PET material accounts for 20%, the stone powder accounts for 75%, the chain extender accounts for 1%, the stearic acid accounts for 1%, the oil body accounts for 1%, and the elastomer accounts for 2%.

8. A plastic flooring substrate made from recycled PET according to claim 1, characterized in that, By mass percentage, the recycled PET material accounts for 20%, the stone powder accounts for 73%, the chain extender accounts for 1.5%, the stearic acid accounts for 1.5%, the oil body accounts for 1.5%, and the elastomer accounts for 2.5%.

9. A method for manufacturing a plastic flooring substrate made from recycled PET as described in any one of claims 1-8, characterized in that, The materials are mixed in proportion, then fed into the equipment for granulation. The substrate particles are then fed into the extruder and extruded.

10. A method for manufacturing a plastic flooring substrate made from recycled PET according to claim 9, characterized in that, The substrate particles are no longer than 3 mm and have a diameter of less than 2 mm.

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