Composite polyvinyl chloride particles and preparation method and application thereof

Abstract

The invention belongs to the technical field of high polymer materials, and particularly relates to composite polyvinyl chloride particles as well as a preparation method and application thereof. The composite polyvinyl chloride particles are prepared from the following components in parts by weight: 50 parts of waste powder generated in UPVC (Unplasticized Polyvinyl Chloride) preparation, 0.01-0.1 part of a silane coupling agent, 40-70 parts of a high-molecular polymer, 30-60 parts of a plasticizer, 1-5 parts of a calcium-zinc stabilizer and 5-25 parts of filler, the high-molecular polymer comprises polyvinyl chloride, a styrene polymer and an acrylonitrile-butadiene-styrene / polycarbonate blend in a weight ratio of (1.3-1.5): 1: (0.6-0.8). According to the invention, recycling of waste powder generated in UPVC preparation can be realized, and the composite polyvinyl chloride particles have excellent comprehensive performance when being used for preparing sealing strips.

Description

Technical Field

[0001] The present invention belongs to the technical field of polymer materials, and particularly relates to a composite polyvinyl chloride particle, a preparation method and an application thereof. Background Art

[0002] The PVC sealing strip for plastic doors and windows is an indispensable part of modern buildings, mainly used to improve the sealing performance of doors and windows, thereby enhancing the sound insulation, waterproof, dustproof and heat preservation effects of buildings. In some special application scenarios, such as laboratories and other places with high requirements for internal environment control, the door and window sealing strips not only need to provide basic sealing functions, but also ensure stable performance under various operating conditions. For example, sealing materials with a low heat shrinkage rate can better meet these high standards.

[0003] Chinese Patent with Publication No. CN116496590B discloses a method for preparing a polyvinyl chloride sealing strip material by using red mud and waste tires and its preparation method. The red mud and waste tires are used as combined fillers to fill and modify the PVC resin matrix. The red mud can act as a rigid filler, a brown colorant, a heat stabilizer and an acidic gas neutralizer, and the waste tire scraps can act as a toughening filler. The synergistic effect of the two improves the thermal stability, mechanical properties and aging resistance of the matrix.

[0004] Rigid polyvinyl chloride pipes (UPVC) have been widely used in many fields such as construction, water supply and drainage, and chemical industry due to their excellent performance. During the preparation process of rigid polyvinyl chloride pipes, a variety of additives need to be added to polyvinyl chloride, such as stabilizers, fillers, titanium dioxide and processing aids. At the same time, stirring is required, and a large amount of dust is easily generated during the stirring process. The PVC resin itself, as one of the main raw materials, may contain a certain proportion of small particles or fine powders. In addition, most of the various additives added to meet specific performance requirements also exist in powder form. All processing steps from the initial batching stage until the final product is formed may involve processes such as material crushing, screening, conveying and mixing, and each link may become a source of dust generation. How to properly handle these dust waste materials is a major problem that needs to be solved urgently. Although at present, after the dust is collected by a dust collector, the clean and uniformly colored dust can be directly recycled and reused, the performance of the prepared products is often still not ideal. Summary of the Invention

[0005] The purpose of the present invention is to provide a composite polyvinyl chloride particle, a preparation method and an application thereof. By using the dust waste generated during the production of PVC for rigid polyvinyl chloride pipes and compounding with a variety of raw materials, the prepared composite polyvinyl chloride particle has excellent mechanical properties and a low heat shrinkage rate, and can meet the requirements of the market for door and window sealing strips under special use conditions.

[0006] To achieve the above object, the present invention provides the following technical solutions: A composite polyvinyl chloride particle, comprising the following components in parts by weight: 50 parts of waste powder generated from UPVC preparation, 0.01 - 0.1 part of silane coupling agent, 40 - 70 parts of high molecular polymer, 30 - 60 parts of plasticizer, 1 - 5 parts of calcium-zinc stabilizer, and 5 - 25 parts of filler.

[0007] Preferably, it comprises the following components in parts by weight: 50 parts of waste powder generated from UPVC preparation, 0.03 - 0.05 part of silane coupling agent, 50 - 60 parts of high molecular polymer, 40 - 50 parts of plasticizer, 1 - 3 parts of calcium-zinc stabilizer, and 10 - 20 parts of filler.

[0008] More preferably, the weight ratio of the high molecular polymer to the plasticizer is (50 - 54):(42 - 45).

[0009] Preferably, it comprises the following components in parts by weight: 50 parts of waste powder generated from UPVC preparation, 0.04 part of silane coupling agent, 54 parts of high molecular polymer, 43 parts of plasticizer, 2 parts of calcium-zinc stabilizer, and 17 parts of filler.

[0010] Preferably, the high molecular polymer comprises polyvinyl chloride, styrene-based polymer, and acrylonitrile-butadiene-styrene / polycarbonate blend in a weight ratio of (1.3 - 1.5):1:(0.6 - 0.8).

[0011] Preferably, the average degree of polymerization of polyvinyl chloride is 970 - 1050, and the apparent density is 0.4 - 0.5 g / cm 3 .

[0012] Preferably, the average degree of polymerization of polyvinyl chloride is 970 - 1050, and the apparent density is 0.45 g / cm 3 . Model: TL-1000, Brand: Tianjin LG Bohai Chemical Co., Ltd.

[0013] Preferably, the styrene-based polymer is selected from polystyrene-maleic anhydride copolymer.

[0014] Preferably, the molar ratio of styrene to maleic anhydride in the polystyrene-maleic anhydride copolymer is one or more of 1:1 and 3:1.

[0015] In a preferred embodiment, the molar ratio of styrene to maleic anhydride in the polystyrene-maleic anhydride copolymer is 1:1, Mw is 5500, and it is end-capped with cumene. The polystyrene-maleic anhydride copolymer can be commercially available or self-made. Commercially available products can be purchased from Hangzhou Yuhao Chemical Technology Co., Ltd.

[0016] Preferably, the melt index of the acrylonitrile-butadiene-styrene / polycarbonate blend is 5-7 g / 10 min under the conditions of 250 °C and 2.16 kg.

[0017] Preferably, the melt index of the acrylonitrile-butadiene-styrene / polycarbonate blend is 6 g / 10 min under the conditions of 250 °C and 2.16 kg. The acrylonitrile-butadiene-styrene / polycarbonate blend can be commercially available or self-made. Commercially available products can be purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., product number A301679.

[0018] Preferably, the plasticizer includes poly(1,2-propylene adipate), bio-based plasticizer, and high and low temperature resistant plasticizer with a weight ratio of 1:(1.2 - 1.5):(0.6 - 0.8).

[0019] The high and low temperature resistant plasticizer has a viscosity of 95 - 130 mPa・s at 25 °C and a specific gravity of 0.970 at 25 / 25 °C. The model of the high and low temperature resistant plasticizer is W-797-ZHID, DIC Corporation.

[0020] The bio-based plasticizer has a viscosity of 550 - 850 mPa・s at 25 °C and a specific gravity of 1.010 at 25 / 25 °C. The model of the bio-based plasticizer is W-1810-BIO, DIC Corporation.

[0021] Preferably, the filler is calcium carbonate.

[0022] Preferably, the silane coupling agent is selected from one or more of silane coupling agent KH550, silane coupling agent KH560, and silane coupling agent KH570.

[0023] The present invention provides a method for preparing composite polyvinyl chloride particles, comprising the following steps: mixing a silane coupling agent with waste powder produced by UPVC, stirring at 90 - 95 °C for 15 - 20 min, sequentially adding a high molecular polymer, a plasticizer, a calcium zinc stabilizer, and a filler, stirring at 85 - 90 °C for 15 - 20 min, and extruding and pelletizing using a twin-screw extruder to obtain composite polyvinyl chloride particles.

[0024] The third aspect of the present invention provides the application of the composite polyvinyl chloride particles in the preparation of sealing strips.

[0025] Compared with the prior art, the advantages and beneficial effects of the present invention are: 1. The present invention uses the waste powder generated in the preparation of UPVC as raw material, and at the same time adds a high molecular polymer, which can improve the tensile strength and tensile impact strength of the PVC sealing strip. By recycling the waste powder in the production process of UPVC, the generation of industrial waste is reduced, which helps to reduce environmental pollution, promote resource recycling, conforms to the concept of green manufacturing and sustainable development, and using the waste powder as part of the raw material can reduce the raw material cost.

[0026] 2. The present invention improves the low temperature performance by adding a specific proportion of high molecular polymer and plasticizer, extends the service life of the sealing strip, reduces the replacement frequency, and reduces the user's usage cost in the long run. This not only improves the durability and reliability of the sealing strip, but also expands its application range, especially in occasions with higher requirements for material performance.

[0027] 3. The present invention adds a compound plasticizer to the system, which can improve the heat shrinkage rate of PVC particles. By optimizing the formula of the plasticizer, the shrinkage of the PVC sealing strip under heating conditions can be effectively reduced. After being used in a high temperature environment or for a period of time, the sealing strip can maintain a more stable size, ensuring that it continuously provides a good sealing effect, making the PVC sealing strip more suitable for use in environments with large temperature changes, and can be applied to environments with higher requirements for the dimensional stability and weather resistance of materials, thereby improving user satisfaction. Specific Embodiments

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0029] Calcium-zinc stabilizer, Shanghai Huiluo Trading Co., Ltd., calcium-zinc stabilizer CZ-11.

[0030] Silane coupling agent, silane coupling agent KH550.

[0031] The waste powder generated in the preparation of UPVC is collected from the dust generated during the stirring process of adding additives to polyvinyl chloride in the preparation process of rigid polyvinyl chloride pipes.

[0032] Example 1

[0033] This example provides a composite PVC particle, which comprises the following components in parts by weight: 50 parts of the waste powder generated in the preparation of UPVC, 0.04 parts of silane coupling agent, 54 parts of high molecular polymer, 43 parts of plasticizer, 2 parts of calcium-zinc stabilizer, and 17 parts of filler.

[0034] The polymer includes polyvinyl chloride, styrene polymer, and acrylonitrile-butadiene-styrene / polycarbonate blend in a weight ratio of 1.4:1:0.7.

[0035] The average degree of polymerization of polyvinyl chloride is 970 - 1050, and the apparent density is 0.45 g / cm 3 . Model: TL-1000, Brand: Tianjin LG Bohai Chemical Co., Ltd.

[0036] The styrene polymer is selected from polystyrene-maleic anhydride copolymer. In the polystyrene-maleic anhydride copolymer, the molar ratio of styrene to maleic anhydride is 1:1, Mw is 5500, and it is capped with cumene. Purchased from Hangzhou Yuhao Chemical Technology Co., Ltd.

[0037] The melt index of the acrylonitrile-butadiene-styrene / polycarbonate blend is 6 g / 10 min under the conditions of 250 °C and 2.16 kg. Purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., product number A301679.

[0038] The plasticizer includes poly(1,2-propylene adipate), bio-based plasticizer, and high and low temperature resistant plasticizer in a weight ratio of 1:1.4:0.7. The high and low temperature resistant plasticizer has a viscosity of 95 - 130 mPa·s at 25 °C and a specific gravity of 0.970 at 25 / 25 °C. The model of the high and low temperature resistant plasticizer is W-797-ZHID, DIC Investment Co., Ltd. The bio-based plasticizer has a viscosity of 550 - 850 mPa·s at 25 °C and a specific gravity of 1.010 at 25 / 25 °C. The model of the bio-based plasticizer is W-1810-BIO, DIC Investment Co., Ltd.

[0039] The filler is calcium carbonate. Shanghai Liangjiang Titanium Dioxide Chemical Products Co., Ltd., light calcium carbonate (rubber and plastic grade).

[0040] The preparation method of the composite polyvinyl chloride particles includes the following steps: Mix the silane coupling agent with the waste powder produced by UPVC, stir at 92 °C for 18 min, then sequentially add the polymer, plasticizer, calcium-zinc stabilizer, and filler, stir at 87 °C for 18 min, and extrude and pelletize using a twin-screw extruder. The temperature of the screw area is 165 °C in zone 1, 180 °C in zone 2, 190 °C in zone 3, 185 °C in zone 4, and 175 °C in zone 5 to obtain the composite polyvinyl chloride particles.

[0041] Example 2

[0042] The difference between this example and Example 1 is: different dosages of the polymer and plasticizer.

[0043] Provided is a composite polyvinyl chloride particle, comprising the following components in parts by weight: 50 parts of waste powder produced by UPVC preparation, 0.04 part of silane coupling agent, 60 parts of high molecular polymer, 40 parts of plasticizer, 2 parts of calcium-zinc stabilizer, and 17 parts of filler.

[0044] Example 3

[0045] This example provides a composite polyvinyl chloride particle, comprising the following components in parts by weight: 50 parts of waste powder produced by UPVC preparation, 0.1 part of silane coupling agent, 70 parts of high molecular polymer, 30 parts of plasticizer, 5 parts of calcium-zinc stabilizer, and 5 parts of filler.

[0046] The high molecular polymer comprises polyvinyl chloride, styrene-based polymer, and acrylonitrile-butadiene-styrene / polycarbonate blend in a weight ratio of 1.3:1:0.6.

[0047] The average degree of polymerization of polyvinyl chloride is 970 - 1050, and the apparent density is 0.45 g / cm 3 . Model: TL-1000, Brand: Tianjin LG Bohai Chemical Co., Ltd.

[0048] The styrene-based polymer is selected from polystyrene-maleic anhydride copolymer. In the polystyrene-maleic anhydride copolymer, the molar ratio of styrene to maleic anhydride is 1:1, Mw is 5500, and it is end-capped with cumene. Purchased from Hangzhou Yuhao Chemical Technology Co., Ltd.

[0049] The melt index of the acrylonitrile-butadiene-styrene / polycarbonate blend is 6 g / 10 min under the conditions of 250°C and 2.16 kg. Purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., product number A301679.

[0050] The plasticizer comprises poly(1,2-propylene adipate), bio-based plasticizer, and high and low temperature resistant plasticizer in a weight ratio of 1:1.2:0.8. The high and low temperature resistant plasticizer has a viscosity of 95 - 130 mPa·s at 25°C and a specific gravity of 0.970 at 25 / 25°C. The model of the high and low temperature resistant plasticizer is W-797-ZHID, DIC Corporation. The bio-based plasticizer has a viscosity of 550 - 850 mPa·s at 25°C and a specific gravity of 1.010 at 25 / 25°C. The model of the bio-based plasticizer is W-1810-BIO, DIC Corporation.

[0051] The filler is calcium carbonate. Shanghai Liangjiang Titanium Dioxide Chemical Products Co., Ltd., light calcium carbonate (rubber and plastic grade).

[0052] The preparation method of the composite polyvinyl chloride particles comprises the following steps: Mix a silane coupling agent with waste powder generated from the preparation of UPVC, stir at 90 °C for 20 min, and successively add a high molecular polymer, a plasticizer, a calcium-zinc stabilizer and a filler, then stir at 85 °C for 15 - 20 min, and extrude and pelletize using a twin-screw extruder. The temperature of the screw area is 165 °C in zone 1, 180 °C in zone 2, 190 °C in zone 3, 185 °C in zone 4 and 175 °C in zone 5 to obtain the composite polyvinyl chloride particles.

[0053] Comparative Example 1 The difference between this comparative example and Example 1 is that: the high molecular polymer is polyvinyl chloride, the average degree of polymerization of polyvinyl chloride is 970 - 1050, and the apparent density is 0.45 g / cm 3 . The model is TL-1000, brand: Tianjin LG Bohua Chemical Co., Ltd.

[0054] Comparative Example 2 The difference between this comparative example and Example 1 is that: the high molecular polymer comprises polyvinyl chloride and a styrene-based polymer in a weight ratio of 1.4:1:.

[0055] The average degree of polymerization of polyvinyl chloride is 970 - 1050, and the apparent density is 0.45 g / cm 3 . The model is TL-1000, brand: Tianjin LG Bohua Chemical Co., Ltd.

[0056] The styrene-based polymer is selected from polystyrene-maleic anhydride copolymer. The molar ratio of styrene to maleic anhydride in the polystyrene-maleic anhydride copolymer is 1:1, Mw is 5500, and it is end-capped with cumene. Purchased from Hangzhou Yuhao Chemical Technology Co., Ltd.

[0057] Comparative Example 3 The difference between this comparative example and Example 1 is that: the high molecular polymer comprises polyvinyl chloride, a styrene-based polymer and an acrylonitrile-butadiene-styrene / polycarbonate blend in a weight ratio of 1:1:1.

[0058] The average degree of polymerization of polyvinyl chloride is 970 - 1050, and the apparent density is 0.45 g / cm3. The model is TL-1000, brand: Tianjin LG Bohua Chemical Co., Ltd.

[0059] The styrene-based polymer is selected from polystyrene-maleic anhydride copolymer. The molar ratio of styrene to maleic anhydride in the polystyrene-maleic anhydride copolymer is 1:1, Mw is 5500, and it is end-capped with cumene. Purchased from Hangzhou Yuhao Chemical Technology Co., Ltd.

[0060] The melt index of the acrylonitrile-butadiene-styrene / polycarbonate blend is 6 g / 10 min under the conditions of 250 °C and 2.16 kg. It is purchased from Shanghai Aladdin Biochemical Technology Co., Ltd., with the product number A301679.

[0061] Comparative Example 4 The difference between this comparative example and Example 1 is that the plasticizer is diisobutyl phthalate.

[0062] Comparative Example 5 The difference between this comparative example and Example 1 is that the plasticizer is poly(1,2-propylene adipate).

[0063] Comparative Example 6 The difference between this comparative example and Example 1 is that the plasticizer includes poly(1,2-propylene adipate) and a high and low temperature resistant plasticizer in a weight ratio of 1:0.7. The high and low temperature resistant plasticizer has a viscosity of 95 - 130 mPa·s at 25 °C and a specific gravity of 0.970 at 25 / 25 °C. The model of the high and low temperature resistant plasticizer is W-797-ZHID, DIC Corporation.

[0064] Comparative Example 7 The difference between this comparative example and Example 1 is that the plasticizer includes poly(1,2-propylene adipate), a bio-based plasticizer, and a high and low temperature resistant plasticizer in a weight ratio of 1:1:1. The high and low temperature resistant plasticizer has a viscosity of 95 - 130 mPa·s at 25 °C and a specific gravity of 0.970 at 25 / 25 °C. The model of the high and low temperature resistant plasticizer is W-797-ZHID, DIC Corporation. The bio-based plasticizer has a viscosity of 550 - 850 mPa·s at 25 °C and a specific gravity of 1.010 at 25 / 25 °C. The model of the bio-based plasticizer is W-1810-BIO, DIC Corporation.

[0065] Performance Test The composite polyvinyl chloride pellets prepared in Examples 1 - 3 and Comparative Examples 1 - 7 were remelted and extruded through a single-screw extruder. The body temperature of the single-screw extruder was 165 °C, and the die temperature of the extrusion molding was 180 °C. After cooling and cutting, sealing strips were obtained. The following performance tests were carried out on the sealing strips: 1. Determine the low-temperature performance at -40 °C with reference to GB5470-2008; 2. Determine the tensile impact strength with reference to GB / T13525-1992; 3. Determine the tensile strength with reference to GB / T1040-2022 at a tensile speed of 250 mm / min; 4. The heat shrinkage rate was measured with reference to GB / T 12002-1989 "Sealing Strips for Plastic Doors and Windows". The test results are shown in Table 1.

[0066] Table 1 Performance Test Results

[0067] As can be seen from Table 1, the tensile strength, tensile impact strength and heat shrinkage rate of Examples 1-3 are excellent, and the low-temperature performance of Example 1 is better. In Examples 2 and 3, the ratio of the polymer and the plasticizer is changed, and the low-temperature performance of the polyvinyl chloride sealing strip decreases, indicating that the polymer and the plasticizer used in the present invention can jointly improve the low-temperature performance of the sealing strip.

[0068] In Comparative Example 1, only polyvinyl chloride is used, and the tensile strength and tensile impact strength of the polyvinyl chloride sealing strip decrease.

[0069] In Comparative Example 2, a styrene-based polymer is added to polyvinyl chloride. Compared with Example 1, the tensile strength and tensile impact strength of the sealing strip decrease. However, compared with Comparative Example 1 where only polyvinyl chloride is used, the tensile impact strength increases and the decrease in tensile strength is not obvious. It is analyzed that the plasticizer used in the present invention helps to improve the compatibility of the styrene-based polymer and PVC and alleviates the rigidity of the styrene-based polymer.

[0070] In Comparative Example 3, different ratios of polymers are used, and the tensile strength and tensile impact strength of the polyvinyl chloride sealing strip both decrease to varying degrees. The toughening agent of the present invention can help the interfacial bonding of the polymer in the system.

[0071] In Comparative Examples 4-7, the composition of the plasticizer is different, and the heat shrinkage rate of the polyvinyl chloride particles becomes higher. It is found in the test process that using poly(1,2-propylene adipate) as the plasticizer in the system of the present invention has better effects than diisobutyl phthalate, but still cannot meet the market demand. In order to further reduce the heat shrinkage rate of the sealing strip, two commercially available plasticizers are added for compounding. By adjusting the ratio, the heat shrinkage rate of the sealing strip can be significantly reduced.

[0072] The above are the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle described in the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A composite polyvinyl chloride particle, characterized in that, It comprises the following components in parts by weight: 50 parts of waste powder generated from UPVC preparation, 0.01 - 0.1 part of silane coupling agent, 40 - 70 parts of high molecular polymer, 30 - 60 parts of plasticizer, 1 - 5 parts of calcium zinc stabilizer, and 5 - 25 parts of filler; the high molecular polymer comprises polyvinyl chloride, styrene-based polymer, and acrylonitrile-butadiene-styrene / polycarbonate blend in a weight ratio of (1.3 - 1.5):1:(0.6 - 0.8).

2. The composite polyvinyl chloride particles according to claim 1, characterized in that, It comprises the following components in parts by weight: 50 parts of waste powder generated from UPVC preparation, 0.03 - 0.05 part of silane coupling agent, 50 - 60 parts of high molecular polymer, 40 - 50 parts of plasticizer, 1 - 3 parts of calcium zinc stabilizer, and 10 - 20 parts of filler.

3. The composite polyvinyl chloride particles according to claim 1, characterized in that, The average degree of polymerization of polyvinyl chloride is 970 - 1050, and the apparent density is 0.4 - 0.5 g / cm 3 .

4. The composite polyvinyl chloride particles according to claim 1, characterized in that, The styrene-based polymer is selected from polystyrene-maleic anhydride copolymer.

5. The composite polyvinyl chloride particles according to claim 4, characterized in that, The molar ratio of styrene to maleic anhydride in the polystyrene-maleic anhydride copolymer is one or more of 1:1 and 3:

1.

6. The composite polyvinyl chloride particles according to claim 1, characterized in that, The melt index of the acrylonitrile-butadiene-styrene / polycarbonate blend is 5 - 7 g / 10 min under the conditions of 250 °C and 2.16 kg.

7. The composite polyvinyl chloride particles according to claim 1, characterized in that, The plasticizer comprises poly(1,2-propanediol adipate), bio-based plasticizer, and high and low temperature resistant plasticizer in a weight ratio of 1:(1.2 - 1.5):(0.6 - 0.8).

8. The composite polyvinyl chloride particles according to claim 7, characterized in that The high and low temperature resistant plasticizer has a viscosity of 95 - 130 mPa·s at 25 °C and a specific gravity of 0.970 at 25 / 25 °C; the bio-based plasticizer has a viscosity of 550 - 850 mPa·s at 25 °C and a specific gravity of 1.010 at 25 / 25 °C.

9. A method for preparing the composite polyvinyl chloride particles according to any one of claims 1-8, characterized in that, It comprises the following steps: Mix the silane coupling agent with the waste powder generated from UPVC preparation, stir at 90 - 95 °C for 15 - 20 min, sequentially add the high molecular polymer, plasticizer, calcium zinc stabilizer, and filler, stir at 85 - 90 °C for 15 - 20 min, and extrude and pelletize using a twin-screw extruder to obtain composite polyvinyl chloride particles.

10. Use of the composite polyvinyl chloride particles according to any one of claims 1 - 8 in the preparation of a sealing strip.

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