Soft PP floor

Abstract

The invention discloses a soft PP floor, and relates to the technical field of floors, the soft PP floor comprises a wear-resistant layer, a decorative layer, a high-multiple base material layer, a low-multiple base material layer and a balance layer in sequence from top to bottom, and the high-multiple base material layer and the low-multiple base material layer are prepared from PP particles, a filler, an antioxidant, a lubricant, a heat stabilizer, a compatilizer and chopped glass fibers. The soft floor is produced by using a PP material through reasonable formula matching, so that the floor meets the environmental protection requirement, meanwhile, the floor has higher mechanical strength, and through reasonable structural configuration, the problems that the soft PP floor material is high in crystallinity, easy to warp and large in contractibility are solved; the method has the advantages of good warping degree, less equipment investment, environmental protection and no plasticizer precipitation risk.

Description

Technical Field

[0001] The invention relates to the technical field of flooring, and in particular to a soft PP flooring. Background Art

[0002] Plastic flooring continues to develop in the direction of green and recyclability. This trend promotes the emergence and development of Non-PVC products. PP (polypropylene) material has the advantages of good processing performance, good elasticity, and aging resistance. It is an environmentally friendly green material for plastic flooring. PP material has good mechanical properties and thermal stability. It has high strength and good toughness, can withstand large impact forces, and can be used at higher temperatures without deformation or melting (operating temperature -20℃ to 120℃).

[0003] In contrast, PVC (polyvinyl chloride) materials have poor mechanical properties and thermal stability, are easily softened and deformed at high temperatures, and have a narrow operating temperature range (-15°C to 55°C). During the production process of soft PVC materials, a large number of plasticizers are added, which is easy to cause environmental pollution. The present invention uses soft PP materials to produce floors to achieve a replacement for soft PVC floors and solve the problem of soft PP floors being prone to warping. Summary of the invention

[0004] Purpose of the invention: The technical problem to be solved by the present invention is to provide a soft PP floor, which solves the problem of poor mechanical properties and thermal stability of existing PVC floor materials.

[0005] Technical Solution

[0006] To solve the above problems, the technical solution provided by the present invention is:

[0007] A soft PP floor comprises, from top to bottom, a wear-resistant layer, a decorative layer, a high-multiple substrate layer, a low-multiple substrate layer, and a balancing layer. The high-multiple substrate layer and the low-multiple substrate layer are made of PP particles, fillers, antioxidants, lubricants, heat stabilizers, compatibilizers, chopped glass fibers, and toughening agents. The material ratio of the high-multiple substrate layer and the low-multiple substrate layer is 10-30% of PP particles, 60-80% of the fillers, 0.1-0.5% of the antioxidants, 0.5-2.0% of the lubricants, 0.5-3.0% of the heat stabilizers, 3-6% of the compatibilizers, 0-2% of the chopped glass fibers, and 2-5% of the toughening agents.

[0008] Furthermore, the PP particles are acrylic acid grafted polypropylene resin, and the melt index is required to be 2-5g / 10min.

[0009] Furthermore, the filler is one or more of calcium carbonate, talc, kaolin and wollastonite, and the particle size is 300-1000 mesh.

[0010] Furthermore, the compatibilizer is polypropylene reactively grafted with maleic anhydride, and the content of maleic anhydride is 0.8%-1.0%.

[0011] Furthermore, the antioxidant is one or more of a hindered phenol antioxidant, a phosphite antioxidant or a thio antioxidant.

[0012] Furthermore, the lubricant is divided into internal lubrication and external lubrication, the internal lubricant is one or more of anhydride internal lubricants or amide internal lubricants, and the external lubricant is one or more of oxidized polyethylene wax, fatty acid amide or high molecular weight silicone powder.

[0013] Furthermore, the chopped glass fibers are aminosilane-coupled modified chopped glass fibers with a length of 5-7 mm and a diameter of 6-10 μm.

[0014] Furthermore, the high-multiple substrate layer formula comprises 15% PP particles, 70% filler, 0.3% antioxidant, 0.7% lubricant, 2% heat stabilizer, 5% compatibilizer, 2% chopped glass fiber, and 5% toughening agent.

[0015] Furthermore, the low-multiple substrate layer comprises 25% PP particles, 60% filler, 0.5% antioxidant, 3% heat stabilizer, 1.5% lubricant, 5% compatibilizer, 2% chopped glass fiber, and 3% toughening agent.

[0016] A manufacturing process of a soft PP floor comprises substrate layer preparation, board pressing, curing, UV layer preparation and cutting.

[0017] Beneficial Effects

[0018] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0019] The technical solution provided by the present invention uses PP materials to produce soft flooring through a reasonable formula, so that the flooring meets environmental protection requirements and also has high mechanical strength. Through reasonable structural configuration, the problems of high crystallinity, easy warping and large shrinkage of the soft PP flooring itself are solved. The soft PP flooring has the advantages of good warping, low equipment investment, environmental protection and no risk of plasticizer precipitation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the structure of Example 1 of the present invention. DETAILED DESCRIPTION

[0021] In order to make the technical solution of the present invention clearer, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] Example 1

[0023] Combined with Figure 1 A soft PP floor, the main structure of which is a high-multiple base material layer and a low-multiple base material layer. The entire structure of the floor includes, from top to bottom, a wear-resistant layer, a decorative layer, a high-multiple base material layer, a low-multiple base material layer, and a balance layer.

[0024] The raw materials of the high-multiple substrate layer and the low-multiple substrate layer include PP particles, fillers, antioxidants, lubricants, heat stabilizers, compatibilizers, chopped glass fibers, and toughening agents;

[0025] PP particles are preferably acrylic acid grafted polypropylene resin, and the melt index is required to be 2-5g / 10min;

[0026] The filler is preferably one or more of calcium carbonate, talc, kaolin and wollastonite, and the particle size is preferably 300-1000 mesh, which mainly plays the role of reducing costs, improving processing performance and increasing dimensional stability;

[0027] The compatibilizer is preferably polypropylene reactively grafted with maleic anhydride, and the maleic anhydride content is 0.8%-1.0%. The compatibilizer significantly improves the adhesion between PP and fillers such as glass fiber, talcum powder, and calcium carbonate by introducing strong polar reactive groups, thereby improving the mechanical properties of the material such as tensile strength, flexural strength, and impact strength.

[0028] The antioxidant is preferably one or more of a hindered phenol antioxidant, a phosphite antioxidant or a thio antioxidant, preferably a hindered phenol antioxidant 1010, which mainly functions to inhibit the oxidation reaction of polypropylene (PP) during processing and use, thereby extending its service life and protecting its physical properties and appearance quality;

[0029] The heat stabilizer is preferably one or more of zinc oxide heat stabilizer, zinc stearate heat stabilizer, and ferrocene heat stabilizer. Adding the heat stabilizer can help resist degradation and decomposition reactions at high temperatures, prevent the breakage of molecular chains and fading of materials, thereby improving temperature resistance.

[0030] Lubricants are divided into internal lubrication and external lubrication. The internal lubricant is preferably one or more of anhydride internal lubricants or amide internal lubricants, and the external lubricant is preferably one or more of oxidized polyethylene wax, fatty acid amide or high molecular weight silicone powder. The internal lubricant reduces the melt viscosity and improves fluidity, making the plastic smoother during the extrusion process; while the external lubricant reduces the friction between the plastic and the metal mold, prevents adhesion and sintering, and ensures the smoothness of the surface of the plastic product and the demoulding effect;

[0031] The toughening agent can be selected from one of the elastomer toughening agents such as EPR, EPDM, LDPE, EVA, CPE, SBS, POE, TPU, polybutadiene rubber, styrene-butadiene rubber, polyisobutylene rubber, butadiene rubber and natural rubber, preferably POE or EPDM, which mainly relieves stress concentration by dispersing or absorbing energy, thereby improving the toughness and impact resistance of the material. The toughening agent can form tiny dispersed phases in the material, which can absorb and disperse energy when impacted, reduce the expansion of cracks, and thus improve the toughness of the material.

[0032] The chopped glass fiber is preferably aminosilane-coupled modified chopped glass fiber with a length of 5-7 mm and a diameter of 6-10 μm, which can enhance the tensile strength and bending modulus, making the PP material harder and tougher as a whole; it can increase the heat deformation temperature of PP so that it can be used at higher temperatures; at the same time, it can reduce the thermal expansion coefficient of PP material and improve dimensional stability;

[0033] The materials used for the high-multiple substrate layer and the low-multiple substrate layer are exactly the same, only the proportions of the materials are different, so as to obtain substrate layers of different multiples. At the same time, whether it is the high-multiple substrate layer or the low-multiple substrate layer, its content is within the material proportion range of the substrate layer. The material proportion of the substrate layer is: PP particles 10-30%, filler 60-80%, antioxidant 0.1-0.5%, lubricant 0.5-2.0%, heat stabilizer 0.5-3.0%, compatibilizer 3-6%, chopped glass fiber 0-2%, toughening agent 2-5%.

[0034] Among them, the preferred formula of the high-multiple substrate layer is 15% PP particles, 70% filler, 0.3% antioxidant, 0.7% lubricant, 2% heat stabilizer, 5% compatibilizer, 2% chopped glass fiber, and 5% toughening agent;

[0035] The low-multiple substrate layer preferably contains 25% PP particles, 60% filler, 0.5% antioxidant, 3% heat stabilizer, 1.5% lubricant, 5% compatibilizer, 2% chopped glass fiber, and 3% toughening agent;

[0036] A production process of soft PP floor:

[0037] The raw materials of the high-multiple substrate layer and the low-multiple substrate layer are two independent process steps in the stages of making the high-multiple substrate layer and the low-multiple substrate layer. The preparation process is exactly the same. The high-multiple substrate layer and the low-multiple substrate layer are obtained only by mixing the raw materials in different ratios.

[0038] Preparation stage of substrate layer:

[0039] 1. The raw materials for preparing the high-multiple substrate layer and the low-multiple substrate layer are automatically weighed and put into the internal mixer for internal mixing. After the temperature reaches ≥120°C, the materials are discharged onto the calendering roller of the open mixer for 5-8 minutes. At this time, the materials are discharged in small fist-shaped pieces.

[0040] 2. Control the temperature of the embossing roller of the open mixer to 140-160℃, and the speed of the open mixer roller to 30-50m / min; use three groups of open mixers to roll the block material from the internal mixing into sheets with a thickness of 0.8-1.8mm;

[0041] 3. The thickness of the sheet substrate is regulated by upper and lower thickness rollers to ensure that the thickness deviation is ±0.05mm. The width is controlled by left and right cutters to ensure that the width is ±1mm to obtain a fixed width and thickness substrate;

[0042] 4. The fixed width and thickness substrate is cooled by circulating cooling water rollers. There are multiple cooling water rollers, preferably nine in total. The cooling temperature of the water rollers is 15-18°C, and the cooling speed is 20-35m / min. The substrate is cooled to shape the substrate.

[0043] 5. The cooled substrate is cut by a cutting machine to obtain a hot-pressed substrate of the required size, which is used for hot pressing to form the substrate layer of the floor.

[0044] Through the above process twice, a high-multiple substrate layer and a low-multiple substrate layer are obtained.

[0045] In addition to the high-multiple substrate layer and the low-multiple substrate layer, the floor also includes a wear-resistant layer, a decorative layer, and a balancing layer. The wear-resistant layer, the decorative layer, and the balancing layer can be made of common materials and processes in the prior art and can be directly produced according to demand, or can be directly purchased and used.

[0046] 6. Plate pressing: Use a multi-layer press to stack the PP wear-resistant layer, PP decorative layer, high-multiple PP base material layer, low-multiple PP base material layer, and balance layer from top to bottom. The PP wear-resistant layer contacts the embossed steel plate to form the surface embossing, and the middle is isolated with PET transparent matte film. The balance layer contacts the bottom-grained steel plate or fine canvas to form the bottom grain, and the middle is also isolated with PET transparent matte film.

[0047] A pressing bracket generally holds four products. The PP wear-resistant layer, PP decorative layer, high-multiple PP base material layer, low-multiple PP base material layer and balance layer are stacked from top to bottom to form one product, that is, a combination of four floor structure layers.

[0048] According to the product size, a 500-ton or 1,000-ton press is used. Multi-stage pressure, temperature and time are used to ensure the quality of the press. The PP wear-resistant layer and PP decorative layer can use prefabricated composite materials on the market, and the surface has been treated and can use PVC existing system UV curing coatings.

[0049] The thickness of PP wear-resistant layer is 0.3-0.7mm, PP decorative layer is 0.10-0.15mm, high-multiple substrate layer is 0.8-1.8mm, low-multiple substrate layer is 0.8-1.8mm, and balance layer is 0.1-0.5mm.

[0050] The following table is a summary of the pressure and time of multi-stage pressing for different products at different temperatures.

[0051]

[0052]

[0053] 7. After hot pressing, curing is carried out. The curing time is ≥ 24 hours and the curing temperature is required to be 25±2℃;

[0054] 8. After curing, apply UV-curing coating on the surface. The surface PP wear-resistant layer has been pre-treated by the film manufacturer to increase the surface roughness and wettability to polar solvents, including but not limited to corona treatment, plasma treatment, etc. The existing UV-curing coating of the PVC system can be directly used for UV. The process is roller coating. First, apply a layer of primer for semi-curing. The primer dosage is 8-15g / ㎡, and the curing energy is 250-600mj / cm 2 After the primer is semi-cured, a layer of topcoat is rolled and fully cured. The amount of topcoat is 8-15g / ㎡, and the curing energy is 1200-2000mj / cm 2 , and obtain UV semi-finished products.

[0055] 9. The UV semi-finished product is tempered, that is, after heating to a certain temperature, the stress is released and then cooled to further control the shrinkage of the product. The tempering time is required to be ≥3min, the outlet temperature of the heating section is 90-100℃, and circulating water is used for cooling. The water temperature is controlled by the mold temperature controller and the cooling water tower. The water temperature of the first cooling section is 40-50℃, and the water temperature of the second cooling section is 25-35℃. The total cooling time is 2min, and the closing temperature of the board is ≤35℃ to obtain the tempered semi-finished product;

[0056] 10. Tempering semi-finished products need to be cured for ≥24 hours at a temperature of 23±2℃;

[0057] 11. After curing, punching or sawing are carried out, and finally edge trimming is carried out to obtain the finished product. This process needs to be carried out in a constant temperature room to ensure the straightness of the product.

[0058] Conduct a comparative experiment:

[0059] Experimental Example I is a board formed by a high-multiple substrate layer of 1.6 mm without adding short glass fibers.

[0060] Experimental Example II is a board formed by adding a high-multiple base material layer of 1.6 mm and short glass fibers.

[0061] Experimental Example III is a board formed by a low-multiple substrate layer of 1.6 mm and without adding short glass fibers.

[0062] Experimental Example IV is a board formed by adding short glass fibers and a low-multiple base material layer of 1.6 mm.

[0063] Experimental Example V is a board having a wear-resistant layer of 0.3 mm, a decorative layer of 0.1 mm, a high-multiplicity base material layer of 1.6 mm, short glass fibers, and no balancing layer.

[0064] Experimental Example VI is a board formed by a wear-resistant layer of 0.3 mm, a decorative layer of 0.1 mm, a high-multiplicity base material layer of 1.6 mm, short glass fibers, and a balancing layer of 0.3 mm.

[0065] Experimental Example VII is a board having a wear-resistant layer of 0.3 mm, a decorative layer of 0.1 mm, a high-multiplicity base material layer of 1.6 mm, short glass fibers, and a balancing layer of 0.5 mm.

[0066] Experimental Example VIII is a composite board having a wear-resistant layer of 0.3 mm, a decorative layer of 0.1 mm, a high-multiplicity base material layer of 0.8 mm with short glass fiber added, a low-multiplicity base material layer of 0.8 mm without short glass fiber added, and a balancing layer of 0.1 mm.

[0067] Experimental Example IX is a composite board with a wear-resistant layer of 0.3 mm, a decorative layer of 0.1 mm, a high-multiplicity base material layer of 0.8 mm with short glass fiber added, a low-multiplicity base material layer of 0.8 mm without short glass fiber added, and a balancing layer of 0.3 mm.

[0068] Experimental Example X is a composite board having a wear-resistant layer of 0.3 mm, a decorative layer of 0.1 mm, a high-multiplicity base layer of 0.8 mm with short glass fiber, a low-multiplicity base layer of 0.8 mm without short glass fiber, and a balancing layer of 0.3 mm.

[0069] Summary table of test structures:

[0070]

[0071] PP soft flooring can replace soft PVC flooring and can be produced using existing equipment for producing LVT flooring. It has the advantages of good warping, low equipment investment, environmental protection and no risk of plasticizer precipitation.

[0072] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A soft PP floor, characterized in that: The invention comprises, from top to bottom, a wear-resistant layer, a decorative layer, a high-multiple substrate layer, a low-multiple substrate layer, and a balancing layer. The high-multiple substrate layer and the low-multiple substrate layer are made of PP particles, fillers, antioxidants, lubricants, heat stabilizers, compatibilizers, chopped glass fibers, and toughening agents. The material ratio of the high-multiple substrate layer and the low-multiple substrate layer is 10-30% of PP particles, 60-80% of fillers, 0.1-0.5% of antioxidants, 0.5-2.0% of lubricants, 0.5-3.0% of heat stabilizers, 3-6% of compatibilizers, 0-2% of chopped glass fibers, and 2-5% of toughening agents.

2. A soft PP floor according to claim 1, characterized in that: The PP particles are acrylic acid grafted polypropylene resin, and the melt index is required to be 2-5g / 10min.

3. The soft PP floor according to claim 1, characterized in that: The filler is one or more of calcium carbonate, talc, kaolin and wollastonite, and the particle size is 300-1000 meshes.

4. The soft PP floor according to claim 1, characterized in that: The compatibilizer is polypropylene reactively grafted with maleic anhydride, and the content of maleic anhydride is 0.8%-1.0%.

5. The soft PP floor according to claim 1, characterized in that: The antioxidant is one or more of a hindered phenol antioxidant, a phosphite antioxidant or a thio antioxidant.

6. The soft PP floor according to claim 1, characterized in that: The lubricant is divided into internal lubrication and external lubrication. The internal lubricant is one or more of anhydride internal lubricants or amide internal lubricants, and the external lubricant is one or more of oxidized polyethylene wax, fatty acid amide or high molecular weight silicone powder.

7. The soft PP floor according to claim 1, characterized in that: The chopped glass fibers are aminosilane-coupled modified chopped glass fibers with a length of 5-7 mm and a diameter of 6-10 μm.

8. The soft PP floor according to claim 1, characterized in that: The high-multiple base material layer comprises 15% PP particles, 70% filler, 0.3% antioxidant, 0.7% lubricant, 2% heat stabilizer, 5% compatibilizer, 2% chopped glass fiber and 5% toughening agent.

9. The soft PP floor according to claim 1, characterized in that: The low-multiple base material layer comprises 25% PP particles, 60% filler, 0.5% antioxidant, 3% heat stabilizer, 1.5% lubricant, 5% compatibilizer, 2% chopped glass fiber and 3% toughening agent.

10. A process for producing a soft PP floor according to any one of claims 1 to 9, characterized in that: Preparation of substrate layer, sheet lamination, curing, preparation of UV layer, cutting.

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