A special material for UHMWPE modified PE pipes

Abstract

The present invention provides a special material for UHMWPE modified PE pipes, which uses HDPE as a raw material and UHMWPE, a composite lubricant, a composite antioxidant, a filler, etc. as modifiers. By regulating the type of raw materials, the ratio of raw materials, and the process parameters, the processing performance of the composite material is improved, and finally a special material for PE pipes with good heat resistance, pressure resistance, and wear resistance is obtained.

Description

Technical Field

[0001] The invention relates to a special material for UHMWPE modified PE pipes, belonging to the technical field of pipe materials. Background Art

[0002] Pipes are essential materials for construction projects, and commonly used ones include water pipes, drainage pipes, gas pipes, heating pipes, electrical conduits, and storm drain pipes. As an important component of chemical building materials, plastic pipes are widely accepted by users for their superior performance, hygiene, environmental friendliness, and low energy consumption. These include UPVC drainage pipes, UPVC water pipes, aluminum-plastic composite pipes, polyethylene (PE) pipes, and polypropylene (PPR) hot water pipes.

[0003] Polyethylene (PE) pipes are primarily classified into two categories: high-density polyethylene (HDPE) and low-density polyethylene (LDPE). Low-density polyethylene (LDPE) offers excellent flexibility, but its compressive strength is relatively low, making it suitable only for low-pressure, small-diameter pipes. High-density polyethylene (HDPE), on the other hand, offers superior compressive resistance and is therefore widely used in pressure pipes.

[0004] Compared with traditional metal pipes, polyethylene pipes are slightly less capable of withstanding temperature, pressure and wear. Therefore, it is still necessary to provide a PE composite material with good heat resistance, pressure resistance and wear resistance to broaden the application prospects of the resulting pipes in high temperature, high pressure, high wear and other environments. Summary of the Invention

[0005] In response to the problems existing in the above-mentioned prior art, the present invention provides a special material for UHMWPE-modified PE pipes, which uses HDPE as raw material and UHMWPE, composite lubricants, composite antioxidants, fillers, etc. as modifiers. By regulating the type of raw materials, raw material ratios, and process parameters, the processing performance of the composite material is improved, and finally a special material for PE pipes with excellent heat resistance, pressure resistance, and wear resistance is obtained.

[0006] The technical solution of the present invention is:

[0007] A special material for UHMWPE modified PE pipe, characterized in that the raw materials include: 60-85 parts of HDPE, 5-30 parts of UHMWPE, 5-10 parts of filler, 0.2-1 parts of composite lubricant, 0.1-0.3 parts of composite antioxidant, and 0.3-1 parts of coupling agent;

[0008] The composite lubricant includes polyethylene wax and stearate;

[0009] The composite antioxidant comprises a main antioxidant and an auxiliary antioxidant, wherein the main antioxidant is a phenolic antioxidant and the auxiliary antioxidant is a phosphite antioxidant.

[0010] Furthermore, the HDPE melt flow rate is 20-50 g / 10 min (230° C., 2.16 kg), and the UHMWPE molecular weight is 2 million-6 million.

[0011] Furthermore, the filler includes at least one of aluminum oxide, magnesium oxide, zinc oxide, and silicon nitride.

[0012] Furthermore, 0.3-1 wt% of silane coupling agent KH550 is used to perform surface treatment on the aluminum oxide, magnesium oxide or zinc oxide.

[0013] Furthermore, the mass ratio of the polyethylene wax to the stearate is (1-5):1; the stearate includes at least one of sodium stearate, zinc stearate, calcium stearate, and magnesium stearate.

[0014] Furthermore, the composite antioxidant includes antioxidant 1010 and antioxidant 168, and the mass ratio of antioxidant 1010 to antioxidant 168 is (1-5):1.

[0015] Furthermore, the coupling agent is KH550 or KH560.

[0016] Furthermore, the preparation raw materials also include 1-5 parts of graphene.

[0017] A method for preparing a special material for UHMWPE modified PE pipes comprises the following steps:

[0018] Adding formulated amounts of HDPE, UHMWPE, filler, composite lubricant, composite antioxidant and coupling agent into a blender and blending to obtain a mixture;

[0019] The mixture was fed into an extensional rheology extruder for extrusion granulation.

[0020] Furthermore, the blending speed is 600-3000 rpm, and the high-speed mixing is 5-30 minutes; the processing temperature of each extrusion granulation zone is 180-240° C., and the speed is 30-100 rpm.

[0021] Therefore, the present invention provides the following effects and / or advantages:

[0022] This invention addresses the shortcomings of HDPE by adding UHMWPE to it as a base plastic. UHMWPE, an ultra-high molecular weight polyethylene (UHMWPE), is an unbranched linear polyethylene with a molecular weight of over 1 million, significantly improving the overall performance of HDPE. However, UHMWPE suffers from poor melt flow, making it difficult to achieve uniform blending with HDPE, making the composite material difficult to process. This invention achieves uniform blending and simplified processing of UHMWPE / HDPE composites by regulating the molecular weight and melt flow rate of the polyethylene, and further combining it with specific modifiers.

[0023] Polyethylene wax and calcium stearate in a specific ratio are used as a composite lubricant. Polyethylene wax has excellent heat resistance and wear resistance, good compatibility with polyethylene materials, and can significantly improve the mixing effect and processing performance of polyethylene composites. Calcium stearate also plays a lubricating role, which can reduce the melt viscosity of the composite material and further improve the processing performance of the material. At the same time, calcium stearate can also be used as a nucleating agent to increase the crystallinity of polyethylene during the processing process, so that the polyethylene can become uniform spherulites, thereby improving the tensile, pressure resistance, wear resistance and other properties of the composite material. By regulating the ratio of polyethylene wax and calcium stearate, a comprehensive improvement in processing performance, heat resistance, pressure resistance and wear resistance is achieved.

[0024] Antioxidant 1010 and antioxidant 168 are used as a composite antioxidant. Antioxidant 1010 is a phenolic antioxidant with excellent antioxidant properties for polyethylene. It can effectively prevent the thermal oxidative degradation of polymer materials during long-term aging. It is also a highly efficient processing stabilizer that can improve the discoloration resistance of polymer materials under high-temperature processing conditions and significantly improve the overall performance of composite materials. Antioxidant 168 is an auxiliary antioxidant and has a good synergistic effect when combined with antioxidant 1010.

[0025] Using HDPE as raw material and UHMWPE, composite lubricant, composite antioxidant, filler, etc. as modifiers, the processing performance of the composite material is improved by regulating the type of raw materials, raw material ratio and process parameters, and finally a special material for PE pipes with good heat resistance, pressure resistance and wear resistance is obtained. The resulting pipe has a compressive strength of more than 70MPa and a Vicat softening temperature of more than 150℃, and the wear resistance is significantly improved.

[0026] It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. DETAILED DESCRIPTION

[0027] In order to facilitate understanding by those skilled in the art, the technical solutions of the present invention are now described in further detail with reference to the examples: It should be understood that the steps mentioned in this embodiment, except for those whose order is specifically stated, can be adjusted in order according to actual needs, and can even be executed simultaneously or partially simultaneously. Obviously, the described implementation mode is a part of the implementation mode of the present invention, not all of the implementation modes. Based on the implementation modes in the present invention, all other implementation modes obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Based on the implementation modes in the present invention, all other implementation modes obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0028] In this embodiment, as used herein, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise specifically defined.

[0029] The specific implementation of the present invention is as follows:

[0030] A special material for UHMWPE modified PE pipe, characterized in that the raw materials include: 60-85 parts of HDPE, 5-30 parts of UHMWPE, 5-10 parts of filler, 0.2-1 parts of composite lubricant, 0.1-0.3 parts of composite antioxidant, and 0.3-1 parts of coupling agent;

[0031] The HDPE melt flow rate is 20-50 g / 10 min (230° C., 2.16 kg), and the UHMWPE molecular weight is 2-6 million;

[0032] The filler comprises at least one of aluminum oxide, magnesium oxide, zinc oxide, and silicon nitride. Optionally, the aluminum oxide, magnesium oxide, or zinc oxide is surface treated with 0.3-1 wt% of a silane coupling agent KH550.

[0033] The composite lubricant includes polyethylene wax and stearate; the mass ratio of the polyethylene wax to the stearate is (1-5):1; the stearate includes at least one of sodium stearate, zinc stearate, calcium stearate, and magnesium stearate;

[0034] The composite antioxidant comprises a primary antioxidant and an auxiliary antioxidant, wherein the primary antioxidant is a phenolic antioxidant, preferably antioxidant 1010, and the auxiliary antioxidant is a phosphite antioxidant, preferably antioxidant 168; the mass ratio of the primary antioxidant to the auxiliary antioxidant is (1-5):1;

[0035] The coupling agent is KH550 or KH560.

[0036] Furthermore, the preparation raw materials also include 1-5 parts of graphene.

[0037] A method for preparing a special material for UHMWPE modified PE pipes comprises the following steps:

[0038] S1, adding the formulated amount of HDPE, UHMWPE, filler, composite lubricant, composite antioxidant and coupling agent into a blender and blending to obtain a mixture, wherein the blending speed is 600 to 3000 rpm and the high-speed mixing is performed for 5 to 30 minutes;

[0039] S2, putting the mixture into an extensional rheological extruder for extrusion granulation, the processing temperature of each extrusion granulation zone is 180-240°C, and the rotation speed is 30-100 rpm.

[0040] Example 1:

[0041] A special material for UHMWPE modified PE pipes, the raw materials for preparation include: 70 parts of HDPE, 30 parts of UHMWPE, 5 parts of filler, 0.5 parts of composite lubricant, 0.2 parts of composite antioxidant, and 0.5 parts of coupling agent.

[0042] The HDPE melt flow rate is 30 g / 10 min (230°C, 2.16 kg), the UHMWPE molecular weight is 4 million, the filler is alumina, the composite lubricant is polyethylene wax and calcium stearate in a mass ratio of 1:1, the composite antioxidant is antioxidant 1010 and antioxidant 168 in a mass ratio of 1:1, and the coupling agent is KH550.

[0043] A method for preparing a special material for UHMWPE modified PE pipes comprises the following steps:

[0044] Add the formulated amount of HDPE, UHMWPE, filler, composite lubricant, composite antioxidant and coupling agent into a blender and blend to obtain a mixture. The blending speed is 1000 rpm and the high-speed mixing is performed for 20 minutes.

[0045] The mixture was put into an extensional rheological extruder for extrusion granulation. The processing temperatures in each zone of the extrusion granulation were 180, 220, 240, 240, 220, 200, and 180° C., respectively, and the rotation speed was 80 rpm.

[0046] The obtained special material is prepared into pipes, and the compressive strength test is performed on them according to GB / T6111-2003, the Vicat softening temperature test is performed on them according to GB / T 1633-2000, and the wear resistance of plastic pipes is tested according to QB / T 5101-2017.

[0047] The obtained pipe has a compressive strength of 58 MPa, a Vicat softening temperature of 138°C, and a wear resistance of 28 mg.

[0048] Example 2:

[0049] Compared with Example 1, the difference is that the filler is replaced by silicon nitride.

[0050] The special material for pipes was prepared in the same manner as in Example 1, and then the special material for pipes was prepared into pipes of the same specifications, and performance tests were performed on them.

[0051] The obtained pipe has a compressive strength of 55 MPa, a Vicat softening temperature of 146°C, and a wear resistance of 20 mg.

[0052] Silicon nitride has good heat resistance and wear resistance, and can further improve the Vicat softening temperature and wear resistance of the pipe.

[0053] Example 3:

[0054] Compared with Example 1, the difference is that the filler is aluminum oxide and silicon nitride in a mass ratio of 1:1.

[0055] The special material for pipes was prepared in the same manner as in Example 1, and then the special material for pipes was prepared into pipes of the same specifications, and performance tests were performed on them.

[0056] The obtained pipe has a compressive strength of 75 MPa, a Vicat softening temperature of 158°C, and a wear resistance of 14 mg.

[0057] Silicon nitride and aluminum oxide can form a very strong bond, resulting in a bonded material with superior performance, greatly improving the overall performance of the pipe.

[0058] Example 4:

[0059] Compared with Example 1, the difference is that 3 parts of graphene are further added to the raw materials, and the graphene is added into the blender together with other raw materials for blending.

[0060] The special material for pipes was prepared in the same manner as in Example 1, and then the special material for pipes was prepared into pipes of the same specifications, and performance tests were performed on them.

[0061] The obtained pipe has a compressive strength of 68 MPa, a Vicat softening temperature of 152°C, and a wear resistance of 18 mg.

[0062] Graphene has good heat resistance and wear resistance, which can further improve the comprehensive performance of the pipe.

[0063] Comparative Example 1:

[0064] Compared with Example 1, the difference is that the HDPE melt flow rate is 10 g / 10 min (230° C., 2.16 kg).

[0065] The special material for pipes was prepared in the same manner as in Example 1, and then the special material for pipes was prepared into pipes of the same specifications, and performance tests were performed on them.

[0066] The obtained pipe has a compressive strength of 32 MPa, a Vicat softening temperature of 121°C, and a wear resistance of 48 mg.

[0067] The HDPE melt flow rate is too low, resulting in poor processing performance and significant deterioration of the overall performance of the pipe.

[0068] Comparative Example 2:

[0069] Compared with Example 1, the difference is that the HDPE melt flow rate is 60 g / 10 min (230° C., 2.16 kg).

[0070] The special material for pipes was prepared in the same manner as in Example 1, and then the special material for pipes was prepared into pipes of the same specifications, and performance tests were performed on them.

[0071] The obtained pipe has a compressive strength of 42 MPa, a Vicat softening temperature of 124°C, and a wear resistance of 46 mg.

[0072] If the HDPE melt flow rate is too high, the performance of the base plastic will deteriorate and the overall performance of the pipe will decrease.

[0073] Comparative Example 3:

[0074] The difference compared with Example 1 is that only polyethylene wax is used as the lubricant.

[0075] The special material for pipes was prepared in the same manner as in Example 1, and then the special material for pipes was prepared into pipes of the same specifications, and performance tests were performed on them.

[0076] The obtained pipe has a compressive strength of 46 MPa, a Vicat softening temperature of 126°C, and a wear resistance of 42 mg.

[0077] Due to the lack of nucleation effect of calcium stearate during processing, the polyethylene matrix failed to form a crystal structure and the overall performance of the resulting pipe deteriorated.

[0078] Comparative Example 4:

[0079] Compared with Example 1, the difference is that only calcium stearate is used as the lubricant.

[0080] The special material for pipes was prepared in the same manner as in Example 1, and then the special material for pipes was prepared into pipes of the same specifications, and performance tests were performed on them.

[0081] The obtained pipe has a compressive strength of 48 MPa, a Vicat softening temperature of 120°C, and a wear resistance of 48 mg.

[0082] Polyethylene wax has excellent heat resistance, wear resistance and lubricity. Its omission leads to a decrease in processing effect and a significant deterioration in heat resistance and wear resistance.

[0083] Comparative Example 5:

[0084] Compared with Example 1, the difference is that only antioxidant 1010 is used.

[0085] The special material for pipes was prepared in the same manner as in Example 1, and then the special material for pipes was prepared into pipes of the same specifications, and performance tests were performed on them.

[0086] The obtained pipe has a compressive strength of 49 MPa, a Vicat softening temperature of 126°C, and a wear resistance of 42 mg.

[0087] The lack of auxiliary effect of phosphite antioxidants causes the decrease of antioxidant activity, resulting in reduced high temperature resistance and the promotion of system mixing.

[0088] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A special material for UHMWPE modified PE pipe, characterized in that: The raw materials for preparation include: 60-85 parts of HDPE, 5-30 parts of UHMWPE, 5-10 parts of filler, 0.2-1 parts of composite lubricant, 0.1-0.3 parts of composite antioxidant, 0.3-1 parts of coupling agent, and 1-5 parts of graphene; The composite lubricant includes polyethylene wax and stearate; The composite antioxidant comprises a primary antioxidant and an auxiliary antioxidant, wherein the primary antioxidant is a phenolic antioxidant and the auxiliary antioxidant is a phosphite antioxidant; The composite antioxidant includes antioxidant 1010 and antioxidant 168; The filler is aluminum oxide and silicon nitride in a mass ratio of 1:1; The HDPE melt flow rate is 20-50 g / 10 min.

2. The UHMWPE modified PE pipe material according to claim 1, characterized in that: The molecular weight of the UHMWPE is 2-6 million.

3. The UHMWPE modified PE pipe material according to claim 1, characterized in that: The mass ratio of the polyethylene wax to the stearate is (1-5):1; the stearate includes at least one of sodium stearate, zinc stearate, calcium stearate, and magnesium stearate.

4. The UHMWPE modified PE pipe material according to claim 1, characterized in that: The mass ratio of the antioxidant 1010 to the antioxidant 168 is (1-5):

1.

5. The UHMWPE modified PE pipe material according to claim 1, characterized in that: The coupling agent is KH550 or KH560.

6. A method for preparing the special material for UHMWPE modified PE pipe according to claim 1, characterized in that: The steps include: Adding the formulated amounts of HDPE, UHMWPE, filler, composite lubricant, composite antioxidant, graphene and coupling agent into a blender and blending to obtain a mixture; The mixture was fed into an extensional rheology extruder for extrusion granulation.

7. The method for preparing a special material for UHMWPE modified PE pipe according to claim 6, characterized in that: The blending speed is 600-3000 rpm, and the high-speed mixing is 5-30 minutes; the processing temperature of each extrusion granulation zone is 180-240° C., and the speed is 30-100 rpm.