Basalt fiber reinforced chlorinated polyvinyl chloride material and preparation method thereof

Abstract

The invention provides a basalt fiber reinforced chlorinated polyvinyl chloride material and a preparation method thereof, and relates to the technical field of polymer composite materials. According to the invention, surface modified basalt fibers are added into chlorinated polyvinyl chloride, cycloheptane and a titanate coupling agent are used for carrying out surface treatment on the basalt fibers, the average length of the basalt fibers is 5-25 [mu] m, and the diameter of the basalt fibers is 0.5-1.5 [mu] m, so that the compatibility of the basalt fibers and polyvinyl chloride is improved, and uniform dispersion in the chlorinated polyvinyl chloride material is ensured; and therefore, the chlorinated polyvinyl chloride pipe has impact resistance, tensile yield stress, vicat softening temperature and hydrostatic performance, and the actual application requirements are comprehensively met.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer composite materials, and more specifically, to a basalt fiber reinforced chlorinated polyvinyl chloride material and a preparation method thereof. Background Art

[0002] Chlorinated polyvinyl chloride (CPVC, PVC-C) is a product of polyvinyl chloride (PVC) that is further chlorinated and modified. It is a new type of polymer composite material with excellent performance. It is widely used in the transportation of hot and cold water inside and outside buildings and in the pipeline system of the industrial field to transport corrosive and high-temperature fluids. However, the chlorine content of chlorinated polyvinyl chloride resin is relatively high, so the prepared pipes have low toughness and poor impact resistance, which makes chlorinated polyvinyl chloride pipes very prone to brittle fracture during storage, transportation, installation and use, especially in low temperature environments. In practical applications, inorganic powder fillers are often added to the formula of chlorinated polyvinyl chloride pipes for blending modification, mainly calcium carbonate. Although the addition of calcium carbonate effectively improves the toughness of the pipe, it will lead to a decrease in the performance of the pipe such as tensile yield stress and Vicat softening temperature.

[0003] Therefore, basalt fiber has become a research focus to replace inorganic materials such as calcium carbonate to enhance the performance of chlorinated polyvinyl chloride. Basalt fiber is a new type of inorganic environmentally friendly green high-performance fiber material, which is made of oxides such as silicon dioxide, aluminum oxide, calcium oxide, magnesium oxide, iron oxide and titanium dioxide. Basalt continuous fiber is not only high in strength, but also has many excellent properties such as electrical insulation, corrosion resistance, and high temperature resistance. It has silicates similar to natural ores, which can be biodegraded in the environment after being discarded, and is harmless to the environment.

[0004] However, basalt fiber and resin often have poor compatibility, and adding basalt fiber to the resin can easily lead to reduced mechanical properties. In order to improve the compatibility and poor bonding between basalt fiber and resin, various methods of modifying basalt fiber have been studied, including plasma surface treatment, acidification, silane coupling, etc. The prior art discloses the use of alkali-free continuous basalt fiber chopped strands surface-treated with a titanate coupling agent to enhance the performance of polyethylene composites. However, the modification steps of basalt fiber are complicated, and the degree of enhancement of the mechanical properties of the composite material after modification is still insufficient, including mechanical properties including impact resistance, tensile yield stress, Vicat softening temperature, hydrostatic performance, etc. There is still room for improvement.

[0005] Therefore, in order to further explore the method of modifying basalt fiber to enhance the mechanical properties of chlorinated polyvinyl chloride, it is necessary to provide a basalt fiber reinforced chlorinated polyvinyl chloride material and a preparation method thereof which has good compatibility with basalt fiber and thus has excellent impact resistance, tensile yield stress, Vicat softening temperature, and hydrostatic performance. Summary of the invention

[0006] In order to overcome the shortcomings of the prior art, the primary purpose of the present invention is to provide a basalt fiber reinforced chlorinated polyvinyl chloride material to achieve high compatibility with basalt fiber, thereby enhancing the impact resistance, tensile yield stress, Vicat softening temperature and hydrostatic performance of the chlorinated polyvinyl chloride material.

[0007] Another object of the present invention is to provide a method for preparing the above-mentioned basalt fiber reinforced chlorinated polyvinyl chloride material.

[0008] Another object of the present invention is to provide the use of the above basalt fiber reinforced chlorinated polyvinyl chloride material in the preparation of chlorinated polyvinyl chloride pipes.

[0009] Another object of the present invention is to provide a chlorinated polyvinyl chloride pipe made from the above-mentioned basalt fiber reinforced chlorinated polyvinyl chloride material.

[0010] To achieve the above object, the present invention adopts the following technical solutions:

[0011] The present invention protects a basalt fiber reinforced chlorinated polyvinyl chloride material, comprising the following components in parts by weight: 100 parts of chlorinated polyvinyl chloride, 5-20 parts of surface-modified basalt fiber, 4-6 parts of heat stabilizer, 2-5 parts of titanium dioxide, and 5-10 parts of impact modifier;

[0012] The surface-modified basalt fiber is a basalt fiber that has been surface-treated with cycloheptane and a titanate coupling agent, and the average length of the basalt fiber is 5 to 25 μm and the diameter is 0.5 to 1.5 μm.

[0013] The role of the cycloheptane is to allow the titanate coupling agent to more evenly coat the basalt fiber, thereby improving the interface bonding between the basalt fiber and chlorinated polyvinyl chloride, thereby improving the compatibility and further improving the mechanical properties.

[0014] The average length of the basalt fiber is 5 to 25 μm, and the fiber diameter is 0.5 to 1.5 μm. The basalt fibers in this size range are evenly dispersed in the CPVC material, have excellent processability, and good performance. The main reason is that the basalt fibers of this size have a larger bonding area with the molecular interface of the CPVC material, so the interaction force between the CPVC and basalt fiber interface is larger, and it can withstand higher energy when subjected to external forces, so the overall performance of the CPVC composite material is higher. However, basalt fibers smaller than this size have a large specific surface area in the CPVC material, a large bonding area with the molecular interface of the CPVC material, and a large bonding strength, resulting in poor processability and large processing dispersion resistance. It is easy to form uneven dispersion of basalt fibers in the CPVC material, resulting in uneven material performance, which is not conducive to bearing higher energy. Basalt fibers larger than this size have a small specific surface area in CPVC materials, a small bonding area with the CPVC material molecular interface, and a low bonding strength. In addition, a void effect will occur at the microscopic level, becoming a stress concentration point. When subjected to external energy impact, the energy absorption is small and the mechanical properties are poor. Therefore, the overall performance of the CPVC composite material is not high.

[0015] Preferably, in the surface-modified basalt fiber, the mass ratio of cycloheptane to titanate coupling agent is 0.5-1.5:1.

[0016] Preferably, the amount of cycloheptane in the surface-modified basalt fiber is 0.5-2.5% of the mass of the basalt fiber.

[0017] Preferably, the method for preparing the surface-modified basalt fiber comprises the following steps:

[0018] The cycloheptane and the titanate coupling agent are mixed evenly in proportion, sprayed into the basalt fiber, and heated and mixed at a high speed to obtain the surface-modified basalt fiber.

[0019] Specifically, the titanate coupling agent is selected from at least one of a monoalkoxy type, a monoalkoxy pyrophosphate type or a chelate type.

[0020] More specifically, the titanate coupling agent is selected from at least one of triisostearyl titanate, tri(dioctyl pyrophosphoryloxy)titanate isopropyl ester or di(octylphenol polyoxyethylene ether) phosphite.

[0021] Specifically, the temperature of the heating and mixing is 115-125°C.

[0022] Preferably, the chlorine content of the chlorinated polyvinyl chloride is 66.5-67.5%, and the determination method is: GBT 7139-2023.

[0023] Preferably, the impact modifier is a core-shell type impact modifier based on silicone-acrylic acid. Specifically, the core of the core-shell type impact modifier includes methyl methacrylate, acrylate and silicone, and the shell includes grafted polymethyl methacrylate.

[0024] Preferably, the heat stabilizer is a calcium zinc stabilizer.

[0025] Preferably, the basalt fiber reinforced chlorinated polyvinyl chloride material further comprises at least one of a processing modifier, a lubricant or a release agent.

[0026] More preferably, the processing modifier is selected from at least one of methyl methacrylate / acrylate copolymer, methyl methacrylate / styrene copolymer, methyl methacrylate / vinyl acetate copolymer or acrylonitrile / styrene copolymer.

[0027] The lubricant is polyethylene wax; the release agent is selected from at least one of oxidized polyethylene wax, silicone release agent or acrylate release agent.

[0028] The present invention also protects a method for preparing a basalt fiber reinforced chlorinated polyvinyl chloride material, comprising the following steps:

[0029] The components are weighed according to the proportions, and the mixture is heated at a high speed at 110-130° C. to obtain the basalt fiber reinforced chlorinated polyvinyl chloride material.

[0030] The application of the above basalt fiber reinforced chlorinated polyvinyl chloride material in the preparation of chlorinated polyvinyl chloride pipes is also within the protection scope of the present invention.

[0031] The present invention also protects a chlorinated polyvinyl chloride pipe, which is prepared from the basalt fiber reinforced chlorinated polyvinyl chloride material.

[0032] Preferably, the chlorinated polyvinyl chloride tube has an outer diameter of 75 mm and a wall thickness of 5.6 mm.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] 1. The present invention provides a basalt fiber reinforced chlorinated polyvinyl chloride material, which has excellent impact resistance, tensile yield stress, Vicat softening temperature, and hydrostatic performance, meets actual use requirements, and can be widely used in the preparation of chlorinated polyvinyl chloride pipes;

[0035] 2. The present invention uses cycloheptane to enhance the coating property of the titanate coupling agent on the basalt fiber, enhances the compatibility of the basalt fiber with the chlorinated polyvinyl chloride material, and provides a new technical solution for the modification of the basalt fiber;

[0036] 3. The present invention selects basalt fibers with an average length of 5 to 25 μm and a diameter of 0.5 to 1.5 μm to achieve the modification of the mechanical properties of chlorinated polyvinyl chloride. The basalt fibers in this size range are evenly dispersed in the CPVC material, have excellent processability and good performance;

[0037] 4. The preparation method described in the technical solution of the present invention is simple, easy to operate, and suitable for large-scale industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is the cross-sectional SEM of the CPVC material modified with basalt fiber.

[0039] Figure 2 This is the surface SEM of CPVC material modified with basalt fiber. DETAILED DESCRIPTION

[0040] The present invention is further described below in conjunction with examples. These examples are only used to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods in the following examples that do not specify specific conditions are usually carried out according to conventional conditions in the art or according to the conditions recommended by the manufacturer; the raw materials, reagents, etc. used, unless otherwise specified, are all raw materials and reagents that can be obtained from commercial channels such as conventional markets. Any non-substantial changes and substitutions made by those skilled in the art on the basis of the present invention belong to the scope of protection claimed by the present invention.

[0041] Some of the reagents selected in the embodiments and comparative examples of the present invention are described as follows:

[0042] The basalt fiber used is treated with cycloheptane and titanate coupling agent. The amount of cycloheptane, the amount of titanate, and the treatment method are shown in step S0 below.

[0043] Surface modified basalt fiber 1#: treated with cycloheptane and titanate coupling agent, the average length of the basalt fiber is 15 μm, the diameter is 1 μm, the amount of cycloheptane is 1.5% of the mass of the basalt fiber, and the mass ratio of the titanate coupling agent to the cycloheptane is 1:1.

[0044] Surface modified basalt fiber 2#: treated with cycloheptane and titanate coupling agent, the average length of the basalt fiber is 5μm, the diameter is 0.5μm, and the amount of cycloheptane used is the same as 1#.

[0045] Surface modified basalt fiber 3#: treated with cycloheptane and titanate coupling agent, the average length of the basalt fiber is 25μm, the diameter is 1.5μm, and the amount of cycloheptane used is the same as 1#.

[0046] Surface modified basalt fiber 4: treated with cycloheptane and titanate coupling agent, the average length and diameter of the basalt fiber is the same as 1#, and the amount of cycloheptane is 0.5% of the mass of the basalt fiber.

[0047] Surface modified basalt fiber 5#: treated with cycloheptane and titanate coupling agent, the average length and diameter of basalt fiber is the same as 1#, and the amount of cycloheptane is 2.5% of the mass of basalt fiber.

[0048] Surface modified basalt fiber 6#: treated with cycloheptane and titanate coupling agent, the average length of the basalt fiber is 15μm, the diameter is 0.1μm, and the amount of cycloheptane used is the same as 1#.

[0049] Surface modified basalt fiber 7#: treated with cycloheptane and titanate coupling agent, the average length of the basalt fiber is 15μm, the diameter is 3μm, and the amount of cycloheptane used is the same as 1#.

[0050] Surface modified basalt fiber 8#: treated with cycloheptane and titanate coupling agent, the average length of basalt fiber is 30μm, the diameter is 1μm, and the amount of cycloheptane is the same as 1#.

[0051] Surface modified basalt fiber 9#: treated with ethanol and titanate coupling agent, the average length of the basalt fiber is 15 μm, the diameter is 1 μm, and the amount of ethanol used is 1.5% of the mass of the basalt fiber.

[0052] Surface modified basalt fiber 10#: treated with white oil and titanate coupling agent, the average length of the basalt fiber is 15μm, the diameter is 1μm, and the amount of white oil used is 1.5% of the mass of the basalt fiber.

[0053] Surface modified basalt fiber 11#: treated with cycloheptane, the average length of the basalt fiber is 15 μm, the diameter is 1 μm, and the amount of cycloheptane used is 1.5% of the mass of the basalt fiber.

[0054] Surface modified basalt fiber 12#: titanate treated, the average length of the basalt fiber is 15 μm, the diameter is 1 μm, and the amount of titanate used is 1.5% of the mass of the basalt fiber.

[0055] Chlorinated polyvinyl chloride: R327, Shandong Gaoxin Chemical Co., Ltd.

[0056] Heat stabilizer: calcium zinc stabilizer, MC6156R / C, Baerlocher New Material Technology Co., Ltd.

[0057] Titanium dioxide: SR-2400, Shandong Dongjia Group Co., Ltd.

[0058] Processing modifier: HPA-40, Shandong Riko Chemical Co., Ltd.

[0059] Impact modifier: S-2001, MITSUBISHI RAYON CO., LTD.

[0060] Lubricant Polyethylene wax: AC-6A, Honeywell.

[0061] Release agent Oxidized polyethylene wax: AC-629A, Honeywell.

[0062] Titanate coupling agent: di(octylphenol polyoxyethylene ether) phosphite, LD-70, Yangzhou Lida Resin Co., Ltd.

[0063] The chlorinated polyvinyl chloride materials and chlorinated polyvinyl chloride pipes of the embodiments and comparative examples of the present invention are prepared by the following process:

[0064] S0. Preparation of surface modified basalt fibers

[0065] 1. Co-treatment of cycloheptane, ethanol or white oil and titanate coupling agent: Mix cycloheptane, ethanol or white oil and titanate coupling agent uniformly according to the mass ratio;

[0066] The basalt fiber is added into the hot mixing cylinder of the high-speed mixer at a mixing temperature of 120°C. After starting at a low speed for 30 seconds, the evenly mixed cycloheptane, ethanol or white oil and titanate coupling agent are added into the hot mixing cylinder of the high-speed mixer by spraying, and then the high-speed mode is started. After running for 5 minutes, it is switched to the low-speed mode to obtain the surface-modified basalt fiber.

[0067] 2. Cycloheptane treatment: Add basalt fiber into the hot mixing cylinder of a high-speed mixer, start it at low speed for 30 seconds, then add cycloheptane into the hot mixing cylinder of the high-speed mixer by spraying, and then start the high-speed mode, and switch to the low-speed mode after running for 5 minutes to obtain surface-modified basalt fiber;

[0068] 3. Titanate treatment: Add basalt fiber into the hot mixing cylinder of a high-speed mixer, start it at low speed for 30 seconds, then add titanate coupling agent into the hot mixing cylinder of the high-speed mixer by spraying, and then start the high-speed mode, and switch to the low-speed mode after running for 5 minutes, so as to obtain surface-modified basalt fiber;

[0069] S1. Preparation of basalt fiber reinforced chlorinated polyvinyl chloride material.

[0070] Accurately weigh chlorinated polyvinyl chloride, surface-modified basalt fiber, heat stabilizer, titanium dioxide, processing modifier, impact modifier, lubricant, and release agent according to the proportions;

[0071] Add weighed chlorinated polyvinyl chloride, surface modified basalt fiber, heat stabilizer, titanium dioxide, processing modifier, impact modifier, lubricant and release agent into the hot mixing cylinder of the high-speed mixer, start high-speed mode stirring, open the discharge valve when the material temperature rises to 120°C, discharge the evenly mixed material (dry mix) into the cold mixing cylinder of the high-speed mixer, open the cold mixing cylinder valve of the high-speed mixer when the dry mix is ​​cooled to 50°C, discharge the dry mix to obtain basalt fiber reinforced chlorinated polyvinyl chloride material;

[0072] S2. Prepare corresponding chlorinated polyvinyl chloride pipes.

[0073] The prepared basalt fiber reinforced chlorinated polyvinyl chloride material is added into a parallel twin-screw extruder, the barrel temperature is set to 160°C to 180°C, and the mold temperature is set to 165°C to 200°C; molding and cutting are performed to obtain the chlorinated rigid polyvinyl chloride pipe;

[0074] The outer diameter of the chlorinated polyvinyl chloride pipe is 75mm and the wall thickness is 5.6mm, which complies with the national standard GB / T 18993.2-2020.

[0075] The performance test methods and standards of the basalt fiber reinforced chlorinated polyvinyl chloride materials of the embodiments and comparative examples of the present invention are as follows:

[0076] Referring to GB / T 18993.2-2020 "Chlorinated polyvinyl chloride (PVC-C) piping systems for hot and cold water", the chlorinated polyvinyl chloride pipes prepared by the basalt fiber reinforced chlorinated polyvinyl chloride material according to the method in S2 were tested;

[0077] Drop weight impact test (TIR / %): GB / T14152;

[0078] Hydrostatic strength (43MPa / 1h): GB / T6111-2018;

[0079] Tensile yield stress / Mpa: GB / T8804.2;

[0080] Vicat softening temperature / ℃: GB / T8802.

[0081] Examples 1 to 6

[0082] This embodiment provides a series of basalt fiber reinforced chlorinated polyvinyl chloride materials, and the weight proportions of the components in the formula are shown in Table 1.

[0083] Table 1 Examples 1 to 6 formulations (parts)

[0084]

[0085]

[0086] Comparative Examples 1 to 9

[0087] This comparative example provides a series of basalt fiber reinforced chlorinated polyvinyl chloride materials, and the weight proportions of the components in the formula are shown in Table 2.

[0088] Table 2 Comparative Examples 1 to 9 Formulations (parts)

[0089]

[0090] The performance test results of the basalt fiber reinforced chlorinated polyvinyl chloride materials in each embodiment and comparative example according to the above-mentioned method are shown in Table 3.

[0091] The performance of the chlorinated polyvinyl chloride pipes prepared from the basalt fiber reinforced chlorinated polyvinyl chloride materials in Examples 1 to 6 and Comparative Examples 1 to 9 was tested according to the above-mentioned method. The test results are shown in Table 3.

[0092] Table 3 Performance test results of various embodiments and comparative examples

[0093]

[0094]

[0095] It can be seen from Table 3 that the pipes made of basalt fiber reinforced chlorinated polyvinyl chloride materials prepared in Examples 1 to 7 of the present invention all have excellent impact resistance, tensile yield stress, Vicat softening temperature and hydrostatic strength performance, among which Example 1 has the best comprehensive performance.

[0096] Comparative Example 1 uses basalt fibers with a diameter smaller than the range, and both the impact resistance and Vicat softening temperature performance are reduced; Comparative Example 2 uses basalt fibers with a diameter larger than the range, and the toughness and heat resistance of the corresponding pipes are reduced; Comparative Example 3 uses basalt fibers with an average length larger than the range, and the toughness, tensile strength and heat resistance of the pipes are slightly improved compared with Comparative Example 2, but are still poorer than those of the embodiment; Comparative Example 4 and Comparative Example 5 respectively use ethanol and white oil to replace the cycloheptane in Example 1, and the performance is poor, indicating the importance of cycloheptane; Comparative Example 6 proves that the use of titanate coupling agent has an important influence on the present invention; Comparative Example 7 proves that titanate alone is not enough to improve the performance of the pipe, and cycloheptane needs to be added; Comparative Examples 8 and 9 prove that the amount of basalt fiber added needs to be within a certain range to achieve the technical effect of the present invention, otherwise the comprehensive performance of the pipe will be greatly reduced.

[0097] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A basalt fiber reinforced chlorinated polyvinyl chloride material, characterized in that: The composition comprises the following components in parts by weight: 100 parts of chlorinated polyvinyl chloride, 5-20 parts of surface modified basalt fiber, 4-6 parts of heat stabilizer, 2-5 parts of titanium dioxide, 5-10 parts of impact modifier; The surface-modified basalt fiber is a basalt fiber that has been surface-treated with cycloheptane and a titanate coupling agent, and the average length of the basalt fiber is 5 to 25 μm and the diameter is 0.5 to 1.5 μm.

2. The basalt fiber reinforced chlorinated polyvinyl chloride material according to claim 1, characterized in that: In the surface-modified basalt fiber, the mass ratio of cycloheptane to titanate coupling agent is 0.5-1.5:

1.

3. The basalt fiber reinforced chlorinated polyvinyl chloride material according to claim 1, characterized in that: The amount of cycloheptane in the surface-modified basalt fiber is 0.5-2.5% of the mass of the basalt fiber.

4. The basalt fiber reinforced chlorinated polyvinyl chloride material according to claim 1 or 2, characterized in that: The chlorine content of the chlorinated polyvinyl chloride is 66.5-67.5%.

5. The basalt fiber reinforced chlorinated polyvinyl chloride material according to claim 1, characterized in that: The basalt fiber reinforced chlorinated polyvinyl chloride material also includes at least one of a processing modifier, a lubricant or a release agent.

6. The basalt fiber reinforced chlorinated polyvinyl chloride material according to claim 1, characterized in that: The heat stabilizer is a calcium zinc stabilizer.

7. The method for preparing the basalt fiber reinforced chlorinated polyvinyl chloride material according to any one of claims 1 to 6, characterized in that: The following steps are involved: The components are weighed according to the proportions, and the mixture is heated at a high speed at 110-130° C. to obtain the basalt fiber reinforced chlorinated polyvinyl chloride material.

8. Use of the basalt fiber reinforced chlorinated polyvinyl chloride material according to any one of claims 1 to 6 in the preparation of chlorinated polyvinyl chloride pipes.

9. A chlorinated polyvinyl chloride pipe, characterized in that: The invention is prepared from the basalt fiber reinforced chlorinated polyvinyl chloride material according to any one of claims 1 to 6.

10. The chlorinated polyvinyl chloride pipe according to claim 9, characterized in that: The chlorinated polyvinyl chloride tube has an outer diameter of 75 mm and a wall thickness of 5.6 mm.

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