Impact-resistant chlorinated polyvinyl chloride composite material and method for preparing the same

Abstract

The application relates to an impact-resistant chlorinated polyvinyl chloride composite material and a preparation method thereof, and belongs to the technical field of polymer composite materials; components of the composite material include: 100 parts of CPVC resin, 6.5-9.5 parts of modified impact-resistant agent, 2.6-3.2 parts of heat stabilizer, 1.5-2 parts of lubricant, 1.2-1.6 parts of processing aid, 0.2-0.25 parts of light stabilizer and 8-11 parts of filler; the modified impact-resistant agent takes a POSS cage structure as a core, and successively contains thioamide-secondary amine-tertiary amine structures on a branched chain; the modified impact-resistant agent forms a polarity gradient, fully extends to macromolecular chains of the CPVC, transmits and dissipates impact energy, meanwhile, the amine structure interacts with chlorine groups in the CPVC molecular chain to form molecular anchoring, the expansion of silver lines is inhibited, the continuity and stability of a bonding interface are maintained, and therefore the composite material can keep high mechanical strength and thermal stability.

Description

Technical Field

[0001] This invention belongs to the field of polymer composite materials technology, specifically, it relates to an impact-resistant chlorinated polyvinyl chloride composite material and its preparation method. Background Technology

[0002] Chlorinated polyvinyl chloride (CPVC) is a high-performance engineering plastic obtained by chlorinating polyvinyl chloride resin. Its chlorine content is increased from 57% to about 65%. The chlorine atoms introduced into the molecular chain enhance the intermolecular forces, significantly improving the material's heat distortion temperature and flame retardant properties. Compared with ordinary PVC, the continuous service temperature of CPVC can be increased from 65℃ to 100℃, while maintaining excellent chemical corrosion resistance, self-extinguishing properties, and mechanical strength. These characteristics make CPVC widely used in high-temperature pipeline systems, chemical anti-corrosion linings, and power cable conduits. However, while the chlorination process improves heat resistance, it also leads to increased rigidity of the CPVC molecular chain and a decrease in free volume, resulting in a significant deterioration in its impact toughness. This inherent defect severely limits the application expansion of CPVC in impact-resistant scenarios.

[0003] Currently, the impact resistance modification of CPVC mainly relies on elastomer blending toughening technology. Commonly used toughening materials include methyl methacrylate-butadiene-styrene terpolymer (MBS) and chlorinated polyethylene (CPE). These elastomer toughening materials can effectively improve the impact resistance of the CPVC matrix to a certain extent, but they have serious technical defects: the toughening efficiency is limited by mechanical strength and thermal properties; the dispersed phase of the elastomer toughening agent disrupts the continuity of the matrix, and excessive addition can cause phase separation, leading to a decrease in strength; at the same time, the softening temperature of the dispersed phase of the elastomer toughening agent is significantly lower than that of the CPVC matrix, becoming a "soft zone" at high temperatures, weakening the matrix stiffness, and thus causing a deterioration in thermal properties; this technical defect restricts the development of high impact-resistant CPVC materials. Summary of the Invention

[0004] In order to solve the technical problems mentioned in the background art, the purpose of this invention is to provide an impact-resistant chlorinated polyvinyl chloride composite material and its preparation method.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] An impact-resistant chlorinated polyvinyl chloride composite material comprises the following components: 100 parts of CPVC resin, 6.5-9.5 parts of modified impact-resistant agent, 2.6-3.2 parts of heat stabilizer, 1.5-2 parts of lubricant, 1.2-1.6 parts of processing aid, 0.2-0.25 parts of light stabilizer, and 8-11 parts of filler.

[0007] The modified impact-resistant agent is prepared by the following method:

[0008] Step A1: Premix methyl 3-mercaptopropionate, N,N-dimethyldipropylenetriamine and anhydrous toluene, purge with dry nitrogen, then add trimethylaluminum and mix. Heat to 75-90℃ and stir for 3.5-4.5 h. After the reaction is complete and cooled, slowly add deionized water to wash. After separating the aqueous phase, remove toluene by vacuum distillation to obtain the intermediate.

[0009] In step A1 above, the molar ratio of methyl 3-mercaptopropionate, N,N-dimethyldipropylenetriamine, trimethylaluminum, and anhydrous toluene is 0.1 mol : 0.105-0.108 mol : 3-4 mmol : 70-100 mL. Under the promotion of trimethylaluminum, N,N-dimethyldipropylenetriamine undergoes amino-ester exchange with methyl 3-mercaptopropionate. The reaction route is as follows:

[0010]

[0011] Step A2: Mix octavinylsilylsilsesquioxane and dichloromethane, then add the intermediate and photosensitizer 1173 and mix well. Apply 60-80 mW / cm 2 The reaction was stirred under ultraviolet irradiation for 2.8-3.6 hours. After the reaction was completed, dichloromethane was removed by rotary evaporation. The substrate was washed with ethanol solution and dried to obtain the modified impact-resistant agent.

[0012] In step A2 above, the ratio of octavinylsilylsilsesquioxane, intermediate, photosensitizer 1173, and dichloromethane is 10 mmol: 80 mmol: 40-60 mg: 120-150 mL. Under photoinitiation, the intermediate undergoes click addition with octavinylsilsesquioxane, and the reaction pathway is as follows:

[0013]

[0014] Preferably, the heat stabilizer is a combination of organotin and calcium-zinc preparations.

[0015] Preferably, the lubricant is a combination of polyethylene wax and stearate.

[0016] Preferably, the filler is surface-modified calcium carbonate.

[0017] A method for preparing an impact-resistant chlorinated polyvinyl chloride composite material is as follows: raw materials are added to a high-speed mixer and mixed evenly, and the discharged material is sent to a twin-screw extruder for melt extrusion and pelletizing to obtain the composite material.

[0018] Furthermore, the temperature process of the twin-screw extruder during melt extrusion is as follows: feeding section 160-170℃, compression section 170-180℃, mixing section 180-190℃, homogenization section 175-180℃.

[0019] The beneficial effects of this invention are:

[0020] This invention improves the impact resistance of CPVC matrix by introducing a modified impact agent for blending. The modified impact agent is prepared by amine-ester exchange of N,N-dimethyldipropylenetriamine and methyl 3-mercaptopropionate to form an intermediate with terminal thiol groups, which is then reacted with octavinyl POSS via click addition. The modified impact agent molecule uses a cage-like POSS core, which responds promptly to external impact by deformation to absorb impact energy, and the deformation induces crazing in the matrix for synergistic toughening. Unlike existing cage-like toughening materials, this modified impact agent uses chemical grafting of multiple amine-containing branches, which, from the POSS end to the terminal end, are successively thioamide-secondary amine-tertiary amine. The polarity gradient forms, increasing the compatibility with the CPVC matrix. This allows the branches to extend fully into the CPVC macromolecular chains. On one hand, the extended branches create larger interfacial contacts, allowing the impact energy to be effectively introduced into the POSS cage structure, resulting in excellent toughening. On the other hand, the impact oscillation energy can be uniformly dispersed by the branches, making full use of the energy dissipated by molecular chain slip. In addition, the amine structure in the branches interacts with the chlorine groups in the CPVC molecular chains to form molecular anchors, inhibiting the expansion of crazes and maintaining the continuity and stability of the bonding interface. This allows the composite material to maintain high mechanical strength and thermal stability. Detailed Implementation

[0021] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0022] Example 1: The specific preparation process of an impact-resistant chlorinated polyvinyl chloride composite material is as follows:

[0023] (1) Preparation of modified impact-resistant agent

[0024] Step A1: Methyl 3-mercaptopropionate, N,N-dimethyldipropylenetriamine, and anhydrous toluene were premixed and protected with dry nitrogen gas. Trimethylaluminum was then added and mixed. The mixture was heated to 75°C and stirred for 4.5 h. During the reaction, the ratio of methyl 3-mercaptopropionate, N,N-dimethyldipropylenetriamine, trimethylaluminum, and anhydrous toluene was 0.1 mol: 0.105 mol: 3 mmol: 70 mL. Trimethylaluminum was a 1.0 M heptane dispersion. After the reaction was completed and cooled to room temperature, deionized water was slowly added and the mixture was washed. The aqueous phase was separated and the toluene was removed by vacuum distillation to obtain the intermediate.

[0025] Step A2: Mix octavinylsilylsilsesquioxane and dichloromethane, then add the intermediate and photosensitizer 1173 and mix well. Apply a 60mW / cm UV mercury lamp.2 The reaction was carried out under ultraviolet irradiation with stirring for 3.6 h. During the reaction, the ratio of octavinylsilylsesquioxane, intermediate, photosensitizer 1173 and dichloromethane was 10 mmol: 80 mmol: 40 mg: 120 mL. After the reaction was completed, dichloromethane was removed by rotary evaporation. The substrate was washed with ethanol solution and dried to obtain the modified impact-resistant agent.

[0026] (2) Compounding and granulation of composite materials

[0027] The raw materials are formulated according to the following weight ratios: 100 parts of CPVC resin, using J-800 type resin raw material; 6.5 parts of modified impact agent, prepared in this embodiment; 3.2 parts of heat stabilizer, using TM-181FS type organotin heat stabilizer and CZ-820 type calcium-zinc heat stabilizer in a weight ratio of 1:3; 2 parts of lubricant, using TL-100 type polyethylene wax and industrial grade calcium stearate in a weight ratio of 2:1; 1.6 parts of processing aid, using ACR-201 type acrylate auxiliary agent; 0.2 parts of light stabilizer, using UV-944 type formulation; and 11 parts of filler, using YP7 type ultrafine modified calcium carbonate powder.

[0028] The above raw materials are added to a high-speed mixer, premixed at a low speed of 600 rpm for 3 minutes, and then mixed at a high speed of 1500 rpm for 10 minutes. The mixture is discharged and fed into a twin-screw extruder. The barrel temperature in the twin-screw extruder is controlled as follows: feeding section 170℃, compression section 180℃, mixing section 190℃, homogenization section 180℃. The mixture is melted and extruded, and after stretching and cooling, it is pelletized to produce a composite material.

[0029] Example 2: The specific preparation process of an impact-resistant chlorinated polyvinyl chloride composite material is as follows:

[0030] (1) Preparation of modified impact-resistant agent

[0031] Step A1: Methyl 3-mercaptopropionate, N,N-dimethyldipropylenetriamine, and anhydrous toluene were premixed and protected with dry nitrogen gas. Trimethylaluminum was then added and mixed. The mixture was heated to 90°C and stirred for 3.5 h. During the reaction, the ratio of methyl 3-mercaptopropionate, N,N-dimethyldipropylenetriamine, trimethylaluminum, and anhydrous toluene was 0.1 mol: 0.108 mol: 4 mmol: 100 mL. Trimethylaluminum was a 1.0 M heptane dispersion. After the reaction was completed and cooled to room temperature, deionized water was slowly added and the mixture was washed. The aqueous phase was separated and the toluene was removed by vacuum distillation to obtain the intermediate.

[0032] Step A2: Mix octavinylsilylsilsesquioxane and dichloromethane, then add the intermediate and photosensitizer 1173 and mix well. Apply an 80mW / cm UV mercury lamp. 2The reaction was carried out under ultraviolet irradiation with stirring for 2.8 h. During the reaction, the ratio of octavinylsilylsesquioxane, intermediate, photosensitizer 1173 and dichloromethane was 10 mmol: 80 mmol: 60 mg: 150 mL. After the reaction was completed, dichloromethane was removed by rotary evaporation. The substrate was washed with ethanol solution and dried to obtain the modified impact-resistant agent.

[0033] (2) Compounding and granulation of composite materials

[0034] The raw materials are formulated according to the following weight ratios: 100 parts of CPVC resin, using J-800 type resin raw material; 9.5 parts of modified impact agent, prepared in this embodiment; 2.6 parts of heat stabilizer, using TM-181FS type organotin heat stabilizer and CZ-820 type calcium-zinc heat stabilizer in a weight ratio of 1:3; 1.5 parts of lubricant, using TL-100 type polyethylene wax and industrial grade calcium stearate in a weight ratio of 2:1; 1.2 parts of processing aid, using ACR-201 type acrylate aid; 0.22 parts of light stabilizer, using UV-944 type formulation; and 8 parts of filler, using YP7 type ultrafine modified calcium carbonate powder.

[0035] The above raw materials are added to a high-speed mixer, premixed at a low speed of 600 rpm for 3 minutes, and then mixed at a high speed of 1500 rpm for 10 minutes. The mixture is discharged and fed into a twin-screw extruder. The barrel temperature in the twin-screw extruder is controlled as follows: feeding section 160℃, compression section 170℃, mixing section 180℃, homogenization section 175℃. The mixture is melted and extruded, and after stretching and cooling, it is pelletized to produce a composite material.

[0036] Example 3: The specific preparation process of an impact-resistant chlorinated polyvinyl chloride composite material is as follows:

[0037] (1) Preparation of modified impact-resistant agent

[0038] Step A1: Methyl 3-mercaptopropionate, N,N-dimethyldipropylenetriamine, and anhydrous toluene were premixed and protected with dry nitrogen gas. Trimethylaluminum was then added and mixed. The mixture was heated to 85°C and stirred for 4 hours. During the reaction, the ratio of methyl 3-mercaptopropionate, N,N-dimethyldipropylenetriamine, trimethylaluminum, and anhydrous toluene was 0.1 mol: 0.106 mol: 3 mmol: 80 mL. Trimethylaluminum was a 1.0 M heptane dispersion. After the reaction was completed and cooled to room temperature, deionized water was slowly added and the mixture was washed. The aqueous phase was separated and the toluene was removed by vacuum distillation to obtain the intermediate.

[0039] Step A2: Mix octavinylsilylsilsesquioxane and dichloromethane, then add the intermediate and photosensitizer 1173 and mix well. Apply a 70mW / cm UV mercury lamp. 2The reaction was carried out under ultraviolet irradiation with stirring for 3.2 h. During the reaction, the ratio of octavinylsilylsesquioxane, intermediate, photosensitizer 1173 and dichloromethane was 10 mmol: 80 mmol: 50 mg: 130 mL. After the reaction was completed, dichloromethane was removed by rotary evaporation. The substrate was washed with ethanol solution and dried to obtain the modified impact-resistant agent.

[0040] (2) Compounding and granulation of composite materials

[0041] The raw materials are formulated according to the following weight ratios: 100 parts of CPVC resin, using J-800 type resin raw material; 8 parts of modified impact agent, prepared in this embodiment; 3 parts of heat stabilizer, using TM-181FS type organotin heat stabilizer and CZ-820 type calcium-zinc heat stabilizer in a weight ratio of 1:3; 1.8 parts of lubricant, using TL-100 type polyethylene wax and industrial grade calcium stearate in a weight ratio of 2:1; 1.4 parts of processing aid, using ACR-201 type acrylate additive; 0.25 parts of light stabilizer, using UV-944 type formulation; and 10 parts of filler, using YP7 type ultrafine modified calcium carbonate powder.

[0042] The above raw materials are added to a high-speed mixer, premixed at a low speed of 600 rpm for 3 minutes, and then mixed at a high speed of 1500 rpm for 10 minutes. The mixture is discharged and fed into a twin-screw extruder. The barrel temperature in the twin-screw extruder is controlled as follows: feeding section 160℃, compression section 170℃, mixing section 185℃, homogenization section 180℃. The mixture is melted and extruded, and after stretching and cooling, it is pelletized to produce a composite material.

[0043] Example 4: The specific preparation process of an impact-resistant chlorinated polyvinyl chloride composite material is as follows:

[0044] (1) Preparation of modified impact-resistant agent

[0045] Step A1: Methyl 3-mercaptopropionate, N,N-dimethyldipropylenetriamine, and anhydrous toluene were premixed and protected with dry nitrogen gas. Trimethylaluminum was then added and mixed. The mixture was heated to 80°C and stirred for 4.2 h. During the reaction, the ratio of methyl 3-mercaptopropionate, N,N-dimethyldipropylenetriamine, trimethylaluminum, and anhydrous toluene was 0.1 mol: 0.107 mol: 4 mmol: 90 mL. Trimethylaluminum was a 1.0 M heptane dispersion. After the reaction was completed and cooled to room temperature, deionized water was slowly added and the mixture was washed. The aqueous phase was separated and the toluene was removed by vacuum distillation to obtain the intermediate.

[0046] Step A2: Mix octavinylsilylsilsesquioxane and dichloromethane, then add the intermediate and photosensitizer 1173 and mix well. Apply a 70mW / cm UV mercury lamp. 2The reaction was carried out under ultraviolet irradiation with stirring for 3 hours. During the reaction, the ratio of octavinylsilylsesquioxane, intermediate, photosensitizer 1173 and dichloromethane was 10 mmol: 80 mmol: 60 mg: 130 mL. After the reaction was completed, dichloromethane was removed by rotary evaporation. The substrate was washed with ethanol solution and dried to obtain the modified impact-resistant agent.

[0047] (2) Compounding and granulation of composite materials

[0048] The raw materials were formulated according to the following weight ratios: 100 parts of CPVC resin, using J-800 type resin raw material; 8.8 parts of modified impact agent, prepared in this embodiment; 2.8 parts of heat stabilizer, using TM-181FS type organotin heat stabilizer and CZ-820 type calcium-zinc heat stabilizer in a weight ratio of 1:3; 1.7 parts of lubricant, using TL-100 type polyethylene wax and industrial grade calcium stearate in a weight ratio of 2:1; 1.4 parts of processing aid, using ACR-201 type acrylate aid; 0.23 parts of light stabilizer, using UV-944 type formulation; and 9 parts of filler, using YP7 type ultrafine modified calcium carbonate powder.

[0049] The above raw materials are added to a high-speed mixer, premixed at a low speed of 600 rpm for 3 minutes, and then mixed at a high speed of 1500 rpm for 10 minutes. The mixture is discharged and fed into a twin-screw extruder. The barrel temperature in the twin-screw extruder is controlled as follows: feeding section 165℃, compression section 175℃, mixing section 190℃, homogenization section 180℃. The mixture is melted and extruded, and after stretching and cooling, it is pelletized to produce a composite material.

[0050] Comparative Example 1: Following the implementation method of Example 4, the modified impact-resistant agent was replaced with an equal amount of B-56 ​​type MBS toughening agent, and the rest of the implementation process was exactly the same.

[0051] Comparative Example 2: Similar to Comparative Example 1, the amount of MBS toughening agent was increased to 22 parts, and the rest of the implementation process was exactly the same.

[0052] Comparative Example 3, following the implementation method of Example 4, replaced the modified impact-resistant agent with an equal amount of octaaminopropyl cage-type polysilsesquioxane, provided by Xi'an Qiyue Biotechnology Co., Ltd., with the rest of the implementation process being exactly the same.

[0053] Samples were taken from the composite material prepared above and injection molded into specimens. The specimens were then subjected to mechanical property tests, specifically including: tensile property testing according to ISO 527-2-2012 standard (specimen type 1B, tensile rate 50 mm / min); flexural property testing according to ISO 178-2019 standard (span 64 mm, rate 2 mm / min); and impact property testing according to ISO 180-2023 standard (V-notch, depth 2 mm). The specimens were also subjected to thermal property tests, specifically including: Vicat softening point testing according to ISO 306-2022 standard (load 10 N, heating rate 120 °C / h); heat distortion temperature testing according to ISO 75-2-2013 standard (load 1.82 MPa, heating rate 120 °C / h); and thermal stability testing under a nitrogen atmosphere with a heating rate of 10 °C / min, detecting the 5% weight loss temperature. Specific test results are shown in Tables 1 and 2.

[0054] Table 1 Results of Mechanical Property Tests

[0055]

[0056]

[0057] Table 2 Thermal performance test results

[0058] Vicat softening point / °C Heat distortion temperature / ℃ 5% weight loss temperature / ℃ Example 1 119 115 283 Example 2 128 121 292 Example 3 120 114 288 Example 4 125 120 296 Comparative Example 1 113 106 267 Comparative Example 2 105 102 245 Comparative Example 3 118 111 285

[0059] As can be seen from the test results in Tables 1 and 2, the introduction of the modified impact-resistant agent in the examples significantly improved the impact resistance of the CPVC matrix, maintained the mechanical strength at a high level, and did not significantly deteriorate the thermal stability.

[0060] In the description of this specification, the references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0061] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. An impact-resistant chlorinated polyvinyl chloride composite material, characterized in that, The composite material comprises: 100 parts of CPVC resin, 6.5-9.5 parts of modified impact agent, 2.6-3.2 parts of heat stabilizer, 1.5-2 parts of lubricant, 1.2-1.6 parts of processing aid, 0.2-0.25 parts of light stabilizer, and 8-11 parts of filler; The modified impact-resistant agent is prepared by the following method: Step A1: Premix methyl 3-mercaptopropionate, N,N-dimethyldipropylenetriamine and anhydrous toluene, purge with dry nitrogen, then add trimethylaluminum and mix. Heat to 75-90℃ and stir for 3.5-4.5 h to prepare an intermediate. Step A2: Mix octavinylsilylsilsesquioxane and dichloromethane, then add the intermediate and photosensitizer 1173 and mix well. Apply 60-80 mW / cm 2 The modified impact-resistant agent was prepared by stirring under ultraviolet irradiation for 2.8-3.6 hours.

2. The impact-resistant chlorinated polyvinyl chloride composite material according to claim 1, characterized in that, The ratio of methyl 3-mercaptopropionate, N,N-dimethyldipropylenetriamine, trimethylaluminum and anhydrous toluene is 0.1 mol: 0.105-0.108 mol: 3-4 mmol: 70-100 mL.

3. The impact-resistant chlorinated polyvinyl chloride composite material according to claim 2, characterized in that, The ratio of octavinylsilylsilsesquioxane, intermediate, photosensitizer 1173 and dichloromethane is 10 mmol: 80 mmol: 40-60 mg: 120-150 mL.

4. The impact-resistant chlorinated polyvinyl chloride composite material according to claim 1, characterized in that, The heat stabilizer is a combination of organotin and calcium-zinc preparations.

5. The impact-resistant chlorinated polyvinyl chloride composite material according to claim 1, characterized in that, The lubricant is a combination of polyethylene wax and stearate.

6. The impact-resistant chlorinated polyvinyl chloride composite material according to claim 1, characterized in that, The filler is surface-modified calcium carbonate.

7. A method for preparing an impact-resistant chlorinated polyvinyl chloride composite material according to any one of claims 1-6, characterized in that, Specifically, the raw materials are added to a high-speed mixer and mixed evenly. The discharged material is then sent to a twin-screw extruder for melt extrusion and pelletizing to obtain a composite material.

8. The method for preparing an impact-resistant chlorinated polyvinyl chloride composite material according to claim 7, characterized in that, The temperature process of the twin-screw extruder during melt extrusion is as follows: feeding section 160-170℃, compression section 170-180℃, mixing section 180-190℃, homogenization section 175-180℃.

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