Puncture-resistant and tear-resistant waterproof membrane and preparation method therefor

Abstract

The present invention relates to the technical field of waterproof materials for railway tunnels, and in particular, to a puncture-resistant and tear-resistant waterproof membrane and a preparation method therefor. The waterproof membrane is made by uniformly mixing a plurality of raw materials, and then subjecting the mixture to a counter-rotating twin-screw extruder and a cooling calendering roller. The waterproof membrane comprises the following raw materials in parts by weight: 15-35 parts of an ethylene-vinyl acetate copolymer, 20-40 parts of an ultra-high molecular weight polyethylene, 20-30 parts of a modified polypropylene, 10-25 parts of an ethylene-octene copolymer, 3-5 parts of silica particles, 3-5 parts of a compatilizer, and 3-5 parts of an antioxidant masterbatch. The waterproof membrane has excellent puncture resistance and tear resistance.

Description

A puncture-resistant and tear-resistant waterproof membrane and its preparation method Technical Field

[0001] This invention relates to the field of waterproof materials for railway tunnels, and in particular to a puncture-resistant and tear-resistant waterproof membrane and its preparation method. Background Technology

[0002] With the rapid development of my country's economy, the modernization of road construction has reached a new level. Due to my country's complex terrain, transportation tunnels have become a crucial part of road construction, with railway tunnels and urban rail transit occupying a significant portion of this sector. Railway tunnels are underground structures, inevitably facing various complex geological conditions, including groundwater development, frost-susceptible rocks, and high-temperature heat damage to rocks within the tunnel. Among these, high-temperature heat damage to rocks within the tunnel is one of the tunnel's hazards, directly affecting traffic safety. This necessitates that waterproofing membranes possess excellent high-temperature puncture resistance.

[0003] The development of waterproofing materials on the market is relatively slow and can no longer meet the complex problems of tunnels. Upgrading waterproofing materials has become one of the important directions in tunnel engineering. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a puncture-resistant and tear-resistant waterproof membrane and its preparation method.

[0005] On the one hand, a puncture-resistant and tear-resistant waterproof membrane is provided, which is made by mixing a variety of raw materials evenly and then passing them through a counter-rotating twin-screw extruder and a cooling calendering roller;

[0006] The raw materials of the waterproof membrane include, by weight: 15-35 parts of ethylene-vinyl acetate copolymer, 20-40 parts of ultra-high molecular weight polyethylene, 20-30 parts of modified polypropylene, 10-25 parts of ethylene-octene copolymer, 3-5 parts of silica particles, 3-5 parts of compatibilizer, and 3-5 parts of antioxidant masterbatch.

[0007] In one embodiment of the present invention, the vinyl acetate content in the ethylene-vinyl acetate copolymer is 15wt% to 35wt%, and its melt flow rate is 5.8 to 6.5 g / 10 min under experimental conditions of 190°C and 2.16 kg weight; the density of the ultra-high molecular weight polyethylene is 0.920 to 0.969 g / cm³.

[0008] In one embodiment of the present invention, the modified polypropylene is a modified polypropylene containing styrene-butadiene-styrene block copolymer segments; the silica particles have a particle diameter of 10~30μm; and the compatibilizer is a maleic anhydride graft compatibilizer or a carboxylic acid type compatibilizer.

[0009] In one embodiment of the present invention, the ethylene-octene copolymer has a density of 0.901~0.920 g / cm³ and a melt flow rate of 0.80~1.10 g / 10 min under experimental conditions of 190°C and 2.16 kg weight.

[0010] As one embodiment of the present invention, the raw materials of the antioxidant masterbatch include, by weight: 50-70 parts of linear low-density polyethylene, 20-30 parts of antioxidant, and 10-20 parts of light stabilizer.

[0011] The linear low-density polyethylene has a density of 0.918~0.923 g / cm³ and a melt flow rate of 0.60~1.30 g / 10 min under experimental conditions of 190℃ and 2.16 kg weight.

[0012] The light stabilizer is a hindered amine light stabilizer; the antioxidant is a mixture of phenolic antioxidant and phosphorus antioxidant in a weight ratio of 1:2, wherein the phenolic antioxidant is antioxidant 1010 or antioxidant 2246; and the phosphorus antioxidant is selected from one or a mixture of two of (2,4-di-tert-butylphenyl) phosphite and pentaerythritol diphosphite.

[0013] On the other hand, a method for preparing a puncture-resistant and tear-resistant waterproof membrane as described in the first aspect is provided, the method comprising:

[0014] Step S1: Add antioxidant, light stabilizer and linear low-density polyethylene to a high-speed mixer and stir at 25±5℃ to prepare antioxidant premix. The antioxidant is a mixture of phenolic antioxidant and phosphorus antioxidant with a weight ratio of 1:2.

[0015] Step S2: The antioxidant premix is ​​processed into antioxidant masterbatch by underwater pelletizing machine;

[0016] Step S3: The antioxidant masterbatch, ethylene-vinyl acetate copolymer, ultra-high molecular weight polyethylene, modified polypropylene, ethylene-octene copolymer, silica particles, and compatibilizer are added to a mixer and mixed evenly to prepare a premixed board material.

[0017] Step S4: The premixed material of the board is continuously produced at a speed of 3.7~4.3m / min using a counter-rotating twin-screw extruder and a cooling calendering roller to produce 4m wide puncture-resistant and tear-resistant waterproof boards.

[0018] In one embodiment of the present invention, in step S1, antioxidants, light stabilizers, and linear low-density polyethylene are mixed in a high-speed mixer for 5 minutes.

[0019] In one embodiment of the present invention, in step S2, the antioxidant premix is ​​melt-blended in an underwater pelletizer, and the melt extrusion temperature is 190~200℃ and the rotation speed is 200~350r / min; the melt extrusion equipment is a counter-rotating twin-screw extruder.

[0020] In one embodiment of the present invention, in step S3, the antioxidant masterbatch, ethylene-vinyl acetate copolymer, ultra-high molecular weight polyethylene, modified polypropylene, ethylene-octene copolymer, silica particles and compatibilizer are mixed in a high-speed mixer for 10 minutes.

[0021] In one embodiment of the present invention, in step S4, the operating temperature of the counter-rotating twin-screw extruder is 200~220℃ and the screw speed is 300r / min;

[0022] The temperature of the cooling calendering roller is 55±5℃, and the diameter of the cooling calendering roller is 600mm.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] The puncture-resistant and tear-resistant waterproof membrane formulation of this invention utilizes ultra-high molecular weight polyethylene, which imparts high tensile strength; modified polypropylene, which provides high puncture resistance; and ethylene-octene copolymer, which enhances tear strength. Silica particles and compatibilizers effectively strengthen the bonds between molecules, resulting in improved overall performance. Antioxidant masterbatch significantly extends the membrane's oxidation time, and the vinyl acetate content is no less than 5%, ensuring weldability and facilitating subsequent use.

[0025] By rationally controlling the mass ratio of each component in the formula, suitable interactions between the components are obtained, maximizing the synergistic effect between the components. This enables high-speed continuous production of 4m wide puncture-resistant and tear-resistant waterproof membranes at a rate of up to 4.3m / min, while ensuring that the waterproof membranes have significantly better tensile and puncture resistance. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the present invention clearer, the invention will be described clearly and completely below in conjunction with specific embodiments.

[0027] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this invention can be purchased from the market or prepared by existing methods.

[0028] Example 1

[0029] A puncture-resistant and tear-resistant waterproof membrane, the preparation method of which includes:

[0030] Step S1: Add 70 parts of linear low-density polyethylene, 20 parts of antioxidant, and 10 parts of light stabilizer to a high-speed mixer and mix for 5 minutes. Stir at 20°C to prepare an antioxidant premix.

[0031] The linear low-density polyethylene is Saudi Sabic 118W, with a density of 0.918 g / cm³ and a melt flow rate of 1.0 g / 10 min under experimental conditions of 190℃ and 2.16 kg weight; the antioxidant is a mixture of antioxidant 1010 and pentaerythritol diphosphite in a weight ratio of 1:2; and the light stabilizer is hindered amine light stabilizer 770.

[0032] Step S2: The antioxidant premix is ​​processed into antioxidant masterbatch by underwater pelletizing machine. The melt extrusion temperature is 190℃ and the rotation speed is 350r / min.

[0033] Step S3: Add 15 parts of ethylene-vinyl acetate copolymer, 20 parts of ultra-high molecular weight polyethylene, 20 parts of modified polypropylene, 10 parts of ethylene-octene copolymer (POE), 3 parts of silica particles, 3 parts of maleic anhydride graft compatibilizer, and 3 parts of antioxidant masterbatch to a mixer and mix for 10 minutes until uniform to prepare a premixed board material.

[0034] The ethylene-vinyl acetate copolymer contains 28 wt% vinyl acetate and has a melt flow rate of 6.2 g / 10 min under experimental conditions of 190℃ and 2.16 kg weight; the ultra-high molecular weight polyethylene is L3000 with a density of 0.969 g / cm³. 3 The silica particles have a diameter of 20 μm; the density of the ethylene-octene copolymer (POE) is 0.904 g / cm³. 3 Its melt flow rate was 1.0 g / 10 min under experimental conditions of 190℃ and 2.16 kg weight;

[0035] The modified polypropylene is a modified PP granule, which is prepared using the method disclosed in Chinese Patent No. CN113667419A. Its formula is the same as that of the intermediate layer in Example 2 of the patent. The raw material composition is 100 parts polypropylene, 10 parts styrene-butadiene-styrene block copolymer, and 0.13 parts dicumyl peroxide. It is produced by a one-step grafting blending method of high temperature extrusion of polypropylene, styrene-butadiene-styrene block copolymer, and dicumyl peroxide.

[0036] Step S4: The premixed sheet material is processed into a 4m wide puncture-resistant and tear-resistant waterproof sheet using a counter-rotating twin-screw extruder and a cooling calendering roller. The extruder operating temperature is 200℃ and the screw speed is 300r / min. The cooling calendering roller temperature is 50℃ and the diameter of the cooling calendering roller is 600mm.

[0037] Example 2

[0038] A puncture-resistant and tear-resistant waterproof membrane, the preparation method of which includes:

[0039] Step S1: Add 60 parts of linear low-density polyethylene, 25 parts of antioxidant, and 15 parts of light stabilizer to a high-speed mixer and mix for 5 minutes. Stir at 25°C to prepare an antioxidant premix.

[0040] The antioxidant is a mixture of phenolic antioxidant and phosphorus antioxidant in a weight ratio of 1:2. The phenolic antioxidant is antioxidant 2246, and the phosphorus antioxidant is a mixture of (2,4-di-tert-butylphenyl) phosphite and pentaerythritol diphosphite. The linear low-density polyethylene and light stabilizer are the same as in Example 1.

[0041] Step S2: The antioxidant premix is ​​processed into antioxidant masterbatch by underwater pelletizing machine. The melt extrusion temperature is 195℃ and the rotation speed is 300r / min.

[0042] Step S3: Add 23 parts of ethylene-vinyl acetate copolymer, 31 parts of ultra-high molecular weight polyethylene, 24 parts of modified polypropylene, 16 parts of ethylene-octene copolymer, 4 parts of silica particles, 4 parts of carboxylic acid compatibilizer, and 4 parts of antioxidant masterbatch to a mixer and mix for 10 minutes to prepare a premixed board material; except for the compatibilizer and antioxidant masterbatch, the rest are the same as in Example 1.

[0043] Step S4: The premixed sheet material is processed into a 4m wide puncture-resistant and tear-resistant waterproof sheet using a counter-rotating twin-screw extruder and a cooling calendering roller. The extruder operating temperature is 210℃ and the screw speed is 300r / min. The cooling calendering roller temperature is 55℃ and the diameter of the cooling calendering roller is 600mm.

[0044] Example 3

[0045] A puncture-resistant and tear-resistant waterproof membrane, the preparation method of which includes:

[0046] Step S1: Add 50 parts of linear low-density polyethylene, 30 parts of antioxidant, and 20 parts of light stabilizer to a high-speed mixer and mix for 5 minutes. Stir at 30°C to prepare an antioxidant premix.

[0047] The antioxidant is a mixture of antioxidant 2246 and (2,4-di-tert-butylphenyl) phosphite in a weight ratio of 1:2, and the linear low-density polyethylene and light stabilizer are the same as in Example 1.

[0048] Step S2: The antioxidant premix is ​​processed into antioxidant masterbatch by underwater pelletizing machine. The melt extrusion temperature is 200℃ and the rotation speed is 200r / min.

[0049] Step S3: Add 35 parts of ethylene-vinyl acetate copolymer, 40 parts of ultra-high molecular weight polyethylene, 30 parts of modified polypropylene, 25 parts of ethylene-octene copolymer, 5 parts of silica particles, 5 parts of carboxylic acid compatibilizer, and 5 parts of antioxidant masterbatch to a mixer and mix for 10 minutes to prepare a premixed board material; except for the compatibilizer and antioxidant masterbatch, the rest are the same as in Example 1.

[0050] Step S4: The premixed sheet material is processed into a 4m wide puncture-resistant and tear-resistant waterproof sheet using a counter-rotating twin-screw extruder and a cooling calendering roller. The extruder operating temperature is 200℃ and the screw speed is 300r / min. The cooling calendering roller temperature is 60℃ and the diameter of the cooling calendering roller is 600mm.

[0051] Example 4

[0052] A puncture-resistant and tear-resistant waterproof membrane, the preparation method of which includes:

[0053] Step S1: Add 55 parts of linear low-density polyethylene, 22 parts of antioxidant, and 26 parts of light stabilizer to a high-speed mixer and mix for 5 minutes. Stir at 27°C to prepare an antioxidant premix.

[0054] The antioxidant is a mixture of phenolic and phosphorus antioxidants in a weight ratio of 1:2. The phenolic antioxidant is antioxidant 2246, and the phosphorus antioxidant is (2,4-di-tert-butylphenyl) phosphite. The linear low-density polyethylene and light stabilizer are the same as in Example 1.

[0055] Step S2: The antioxidant premix is ​​processed into antioxidant masterbatch by underwater pelletizing machine. The melt extrusion temperature is 193℃ and the rotation speed is 300r / min.

[0056] Step S3: Add 18 parts of ethylene-vinyl acetate copolymer, 22 parts of ultra-high molecular weight polyethylene, 23 parts of modified polypropylene, 13 parts of ethylene-octene copolymer, 3 parts of silica particles, 4 parts of carboxylic acid compatibilizer, and 5 parts of antioxidant masterbatch to a mixer and mix for 10 minutes to prepare a premixed board material; except for the compatibilizer and antioxidant masterbatch, the rest are the same as in Example 1.

[0057] Step S4: The premixed sheet material is processed into a 4m wide puncture-resistant and tear-resistant waterproof sheet using a counter-rotating twin-screw extruder and a cooling calendering roller. The extruder operating temperature is 208℃ and the screw speed is 300r / min. The cooling calendering roller temperature is 55℃ and the diameter of the cooling calendering roller is 600mm.

[0058] Example 5

[0059] A puncture-resistant and tear-resistant waterproof membrane, the preparation method of which includes:

[0060] Step S1: Add 58 parts of linear low-density polyethylene, 26 parts of antioxidant, and 13 parts of light stabilizer to a high-speed mixer and mix for 5 minutes. Stir at 25°C to prepare an antioxidant premix.

[0061] The antioxidant is a mixture of phenolic antioxidant and phosphorus antioxidant in a weight ratio of 1:2. The phenolic antioxidant is antioxidant 2246, and the phosphorus antioxidant is pentaerythritol diphosphite. The linear low-density polyethylene and light stabilizer are the same as in Example 1.

[0062] Step S2: The antioxidant premix is ​​processed into antioxidant masterbatch by underwater pelletizing machine. The melt extrusion temperature is 200℃ and the rotation speed is 320r / min.

[0063] Step S3: Add 20 parts of ethylene-vinyl acetate copolymer, 35 parts of ultra-high molecular weight polyethylene, 27 parts of modified polypropylene, 17 parts of ethylene-octene copolymer, 4 parts of silica particles, 3 parts of carboxylic acid compatibilizer, and 5 parts of antioxidant masterbatch to a mixer and mix for 10 minutes to prepare a premixed board material; except for the compatibilizer and antioxidant masterbatch, the rest are the same as in Example 1.

[0064] Step S4: The premixed sheet material is processed into a 4m wide puncture-resistant and tear-resistant waterproof sheet using a counter-rotating twin-screw extruder and a cooling calendering roller. The extruder operating temperature is 215℃ and the screw speed is 300r / min. The cooling calendering roller temperature is 55℃ and the diameter of the cooling calendering roller is 600mm.

[0065] Example 6

[0066] A puncture-resistant and tear-resistant waterproof membrane, the preparation method of which includes:

[0067] Step S1: Add 62 parts of linear low-density polyethylene, 29 parts of antioxidant, and 17 parts of light stabilizer to a high-speed mixer and mix for 5 minutes. Stir at 26°C to prepare an antioxidant premix.

[0068] The antioxidant is a mixture of phenolic antioxidant and phosphorus antioxidant in a weight ratio of 1:2. The phenolic antioxidant is antioxidant 2246, and the phosphorus antioxidant is a mixture of (2,4-di-tert-butylphenyl) phosphite and pentaerythritol diphosphite. The linear low-density polyethylene and light stabilizer are the same as in Example 1.

[0069] Step S2: The antioxidant premix is ​​processed into antioxidant masterbatch by underwater pelletizing machine. The melt extrusion temperature is 198℃ and the rotation speed is 310r / min.

[0070] Step S3: Add 30 parts of ethylene-vinyl acetate copolymer, 29 parts of ultra-high molecular weight polyethylene, 25 parts of modified polypropylene, 22 parts of ethylene-octene copolymer, 5 parts of silica particles, 3 parts of carboxylic acid compatibilizer, and 4 parts of antioxidant masterbatch to a mixer and mix for 10 minutes to prepare a premixed board material; except for the compatibilizer and antioxidant masterbatch, the rest are the same as in Example 1.

[0071] Step S4: The premixed sheet material is processed into a 4m wide puncture-resistant and tear-resistant waterproof sheet using a counter-rotating twin-screw extruder and a cooling calendering roller. The extruder operating temperature is 220℃ and the screw speed is 300r / min. The cooling calendering roller temperature is 55℃ and the diameter of the cooling calendering roller is 600mm.

[0072] Example 7

[0073] A puncture-resistant and tear-resistant waterproof membrane, the preparation method of which includes:

[0074] Step S1: Add 70 parts of linear low-density polyethylene, 20 parts of antioxidant, and 10 parts of light stabilizer to a high-speed mixer and mix for 5 minutes. Stir at 20°C to prepare an antioxidant premix.

[0075] The linear low-density polyethylene has a density of 0.920 g / cm³ and a melt flow rate of 0.60 g / 10 min under experimental conditions of 190℃ and 2.16 kg weight; the antioxidant is a mixture of antioxidant 1010 and pentaerythritol diphosphite in a weight ratio of 1:2; and the light stabilizer is hindered amine light stabilizer 770.

[0076] Step S2: The antioxidant premix is ​​processed into antioxidant masterbatch by underwater pelletizing machine. The melt extrusion temperature is 190℃ and the rotation speed is 350r / min.

[0077] Step S3: Add 15 parts of ethylene-vinyl acetate copolymer, 20 parts of ultra-high molecular weight polyethylene, 20 parts of modified polypropylene, 10 parts of ethylene-octene copolymer (POE), 3 parts of silica particles, 3 parts of maleic anhydride graft compatibilizer, and 3 parts of antioxidant masterbatch to a mixer and mix for 10 minutes until uniform to prepare a premixed board material.

[0078] The ethylene-vinyl acetate copolymer contained 15 wt% vinyl acetate and had a melt flow rate of 5.8 g / 10 min under experimental conditions of 190°C and 2.16 kg weight; the ultra-high molecular weight polyethylene had a density of 0.920 g / cm³; the silica particles had a particle diameter of 10 μm; the ethylene-octene copolymer had a density of 0.901 g / cm³ and a melt flow rate of 1.1 g / 10 min under experimental conditions of 190°C and 2.16 kg weight; the modified polypropylene was the same as in Example 1.

[0079] Step S4: The premixed sheet material is processed into a 4m wide puncture-resistant and tear-resistant waterproof sheet using a counter-rotating twin-screw extruder and a cooling calendering roller. The extruder operating temperature is 200℃ and the screw speed is 300r / min. The cooling calendering roller temperature is 50℃ and the diameter of the cooling calendering roller is 600mm.

[0080] Example 8

[0081] A puncture-resistant and tear-resistant waterproof membrane, the preparation method of which includes:

[0082] Step S1: Add 70 parts of linear low-density polyethylene, 20 parts of antioxidant, and 10 parts of light stabilizer to a high-speed mixer and mix for 5 minutes. Stir at 20°C to prepare an antioxidant premix.

[0083] The linear low-density polyethylene has a density of 0.923 g / cm³ and a melt flow rate of 1.30 g / 10 min under experimental conditions of 190℃ and 2.16 kg weight; the antioxidant is a mixture of antioxidant 1010 and pentaerythritol diphosphite in a weight ratio of 1:2; and the light stabilizer is hindered amine light stabilizer 770.

[0084] Step S2: The antioxidant premix is ​​processed into antioxidant masterbatch by underwater pelletizing machine. The melt extrusion temperature is 190℃ and the rotation speed is 350r / min.

[0085] Step S3: Add 15 parts of ethylene-vinyl acetate copolymer, 20 parts of ultra-high molecular weight polyethylene, 20 parts of modified polypropylene, 10 parts of ethylene-octene copolymer (POE), 3 parts of silica particles, 3 parts of maleic anhydride graft compatibilizer, and 3 parts of antioxidant masterbatch to a mixer and mix for 10 minutes until uniform to prepare a premixed board material.

[0086] The ethylene-vinyl acetate copolymer contained 35 wt% vinyl acetate and had a melt flow rate of 6.5 g / 10 min under experimental conditions of 190 °C and 2.16 kg weight; the ultra-high molecular weight polyethylene had a density of 0.940 g / cm³; the silica particles had a particle diameter of 30 μm; the ethylene-octene copolymer had a density of 0.901 g / cm³ and a melt flow rate of 0.80 g / 10 min under experimental conditions of 190 °C and 2.16 kg weight; the modified polypropylene was the same as in Example 1.

[0087] Step S4: The premixed sheet material is processed into a 4m wide puncture-resistant and tear-resistant waterproof sheet using a counter-rotating twin-screw extruder and a cooling calendering roller. The extruder operating temperature is 200℃ and the screw speed is 300r / min. The cooling calendering roller temperature is 50℃ and the diameter of the cooling calendering roller is 600mm.

[0088] Comparative Example 1

[0089] A waterproof membrane, the preparation method of which includes:

[0090] Step S1: Add 60 parts of linear low-density polyethylene, 25 parts of antioxidant, and 15 parts of light stabilizer to a high-speed mixer and mix for 5 minutes. Stir at 25°C to prepare an antioxidant premix.

[0091] The antioxidant is a mixture of phenolic antioxidant and phosphorus antioxidant in a weight ratio of 1:2. The phenolic antioxidant is antioxidant 2246, and the phosphorus antioxidant is a mixture of (2,4-di-tert-butylphenyl) phosphite and pentaerythritol diphosphite. The linear low-density polyethylene and light stabilizer are the same as in Example 1.

[0092] Step S2: The antioxidant premix is ​​processed into antioxidant masterbatch by underwater pelletizing machine. The melt extrusion temperature is 195℃ and the rotation speed is 300r / min.

[0093] Step S3: Add 23 parts of ethylene-vinyl acetate copolymer, 31 parts of ultra-high molecular weight polyethylene, 16 parts of ethylene-octene copolymer, 4 parts of silica particles, 4 parts of carboxylic acid compatibilizer, and 4 parts of antioxidant masterbatch to a mixer and mix for 10 minutes to prepare a premixed board material; except for the compatibilizer and antioxidant masterbatch, the rest are the same as in Example 1.

[0094] Step S4: The premixed sheet material is processed into a 4m wide waterproof sheet using a counter-rotating twin-screw extruder and a cooling calendering roller. The extruder operating temperature is 210℃ and the screw speed is 300r / min. The cooling calendering roller temperature is 55℃ and the diameter of the cooling calendering roller is 600mm.

[0095] Comparative Example 2

[0096] A waterproof membrane, the preparation method of which includes:

[0097] Step S1: Add 60 parts of linear low-density polyethylene, 25 parts of antioxidant, and 15 parts of light stabilizer to a high-speed mixer and mix for 5 minutes. Stir at 25°C to prepare an antioxidant premix.

[0098] The antioxidant is a mixture of phenolic antioxidant and phosphorus antioxidant in a weight ratio of 1:2. The phenolic antioxidant is antioxidant 2246, and the phosphorus antioxidant is a mixture of (2,4-di-tert-butylphenyl) phosphite and pentaerythritol diphosphite. The linear low-density polyethylene and light stabilizer are the same as in Example 1.

[0099] Step S2: The antioxidant premix is ​​processed into antioxidant masterbatch by underwater pelletizing machine. The melt extrusion temperature is 195℃ and the rotation speed is 300r / min.

[0100] Step S3: Add 23 parts of ethylene-vinyl acetate copolymer, 31 parts of ultra-high molecular weight polyethylene, 24 parts of modified polypropylene, 4 parts of silica particles, 4 parts of carboxylic acid compatibilizer, and 4 parts of antioxidant masterbatch to a mixer and mix for 10 minutes to prepare a premixed board material; except for the compatibilizer and antioxidant masterbatch, the rest are the same as in Example 1.

[0101] Step S4: The premixed sheet material is processed into a 4m wide waterproof sheet using a counter-rotating twin-screw extruder and a cooling calendering roller. The extruder operating temperature is 210℃ and the screw speed is 300r / min. The cooling calendering roller temperature is 55℃ and the diameter of the cooling calendering roller is 600mm.

[0102] Comparative Example 3

[0103] A waterproof membrane, the preparation method of which includes:

[0104] Step S1: Add 60 parts of linear low-density polyethylene, 25 parts of antioxidant, and 15 parts of light stabilizer to a high-speed mixer and mix for 5 minutes. Stir at 25°C to prepare an antioxidant premix.

[0105] The antioxidant is a mixture of phenolic antioxidant and phosphorus antioxidant in a weight ratio of 1:2. The phenolic antioxidant is antioxidant 2246, and the phosphorus antioxidant is a mixture of (2,4-di-tert-butylphenyl) phosphite and pentaerythritol diphosphite. The linear low-density polyethylene and light stabilizer are the same as in Example 1.

[0106] Step S2: The antioxidant premix is ​​processed into antioxidant masterbatch by underwater pelletizing machine. The melt extrusion temperature is 195℃ and the rotation speed is 300r / min.

[0107] Step S3: Add 23 parts of ethylene-vinyl acetate copolymer, 31 parts of ultra-high molecular weight polyethylene, 24 parts of modified polypropylene, 16 parts of ethylene-octene copolymer, 4 parts of carboxylic acid compatibilizer, and 4 parts of antioxidant masterbatch to a mixer and mix for 10 minutes to prepare a premixed board material; except for the compatibilizer and antioxidant masterbatch, the rest are the same as in Example 1.

[0108] Step S4: The premixed sheet material is processed into a 4m wide waterproof sheet using a counter-rotating twin-screw extruder and a cooling calendering roller. The extruder operating temperature is 210℃ and the screw speed is 300r / min. The cooling calendering roller temperature is 55℃ and the diameter of the cooling calendering roller is 600mm.

[0109] Example 1

[0110] The production rates of the 4m wide waterproof membranes in Examples 1-6 and Comparative Examples 1-3 were obtained using the following methods, and the results are shown in Table 1.

[0111] Preparation rate test method: For any roll of waterproof membrane, the production rate of the roll of waterproof membrane is obtained by the formula v=S / t, where S is the length of the roll of waterproof membrane and t is the preparation time of the roll of waterproof membrane.

[0112] Repeat the above steps to obtain the production rate of each roll of waterproof membrane, and average all the production rates to obtain the final production rate.

[0113] Table 1 Production Rate of 4m Wide Waterproof Membrane

[0114]

[0115] As shown in Table 1, the production rate of the 4m wide waterproof membrane in Examples 1-6 is as high as 3.7-4.3 m / min.

[0116] Example 2

[0117] The products obtained in Examples 1-6 and Comparative Examples 1-3 were subjected to tear strength, tensile strength at break, elongation at break, puncture strength, high-temperature puncture resistance, and VA content performance tests. The results are shown in Table 2.

[0118] The performance test indicators and methods are as follows: tear strength, tensile strength at break, elongation at break, and puncture strength are tested according to the standard QCR562.1-2018; high temperature puncture: first place in a 70℃ oven for 1 hour, and then conduct the puncture test in a 70℃ environmental chamber; VA content is tested according to the standard method of GB / T 30925-2014.

[0119] Table 2 Performance test results of products obtained from each embodiment and comparative example

[0120]

[0121] As shown in Table 2, the waterproof membranes obtained in Examples 1-6 of this invention exhibit excellent mechanical properties. Furthermore, the addition of modified polypropylene enhances all properties of the material, with the greatest impact on puncture strength and high-temperature puncture resistance. The ethylene-octene copolymer has good compatibility with polyolefins, effectively improving the tear strength of the material. Silica particles help increase the compatibility of various materials during processing, thereby improving the mechanical properties of the material.

Claims

1. A puncture-resistant and tear-resistant waterproof membrane, characterized in that, The waterproof membrane is made by mixing various raw materials evenly and then extruding them through a counter-rotating twin-screw extruder and cooling calendering rollers. The raw materials of the waterproof membrane include, by weight: 15-35 parts of ethylene-vinyl acetate copolymer, 20-40 parts of ultra-high molecular weight polyethylene, 20-30 parts of modified polypropylene, 10-25 parts of ethylene-octene copolymer, 3-5 parts of silica particles, 3-5 parts of compatibilizer, and 3-5 parts of antioxidant masterbatch.

2. A puncture and tear resistant waterproof sheet according to claim 1, wherein The vinyl acetate content in the ethylene-vinyl acetate copolymer is 15wt%~35wt%, and its melt flow rate is 5.8~6.5g / 10min under experimental conditions of 190℃ and 2.16kg weight; the density of the ultra-high molecular weight polyethylene is 0.920~0.969g / cm³.

3. A puncture and tear resistant waterproof sheet according to claim 1, wherein The modified polypropylene is a modified polypropylene containing styrene-butadiene-styrene block copolymer segments; the silica particles have a particle diameter of 10~30μm; the compatibilizer is a maleic anhydride graft compatibilizer or a carboxylic acid type compatibilizer.

4. A puncture and tear resistant waterproof sheet according to claim 1, wherein The ethylene-octene copolymer has a density of 0.901~0.920 g / cm³ and a melt flow rate of 0.80~1.10 g / 10 min under experimental conditions of 190℃ and 2.16 kg weight.

5. A puncture and tear resistant waterproof sheet according to claim 1, wherein The raw materials of the antioxidant masterbatch include, by weight: 50-70 parts of linear low-density polyethylene, 20-30 parts of antioxidant, and 10-20 parts of light stabilizer. The linear low-density polyethylene has a density of 0.918~0.923 g / cm³ and a melt flow rate of 0.60~1.30 g / 10 min under experimental conditions of 190℃ and 2.16 kg weight. The light stabilizer is a hindered amine light stabilizer; the antioxidant is a mixture of phenolic antioxidant and phosphorus antioxidant in a weight ratio of 1:2, wherein the phenolic antioxidant is antioxidant 1010 or antioxidant 2246; and the phosphorus antioxidant is selected from one or a mixture of two of (2,4-di-tert-butylphenyl) phosphite and pentaerythritol diphosphite.

6. A method of manufacturing a puncture and tear resistant waterproof sheet as claimed in any one of claims 1 to 5, characterized in that, The method includes: Step S1: Add antioxidant, light stabilizer and linear low-density polyethylene to a high-speed mixer and stir at 25±5℃ to prepare antioxidant premix. The antioxidant is a mixture of phenolic antioxidant and phosphorus antioxidant with a weight ratio of 1:

2. Step S2: The antioxidant premix is ​​processed into antioxidant masterbatch by underwater pelletizing machine; Step S3: The antioxidant masterbatch, ethylene-vinyl acetate copolymer, ultra-high molecular weight polyethylene, modified polypropylene, ethylene-octene copolymer, silica particles, and compatibilizer are added to a mixer and mixed evenly to prepare a premixed board material. Step S4: The premixed material of the board is continuously produced at a speed of 3.7~4.3m / min using a counter-rotating twin-screw extruder and a cooling calendering roller to produce 4m wide puncture-resistant and tear-resistant waterproof boards.

7. A method of making a puncture and tear resistant waterproof sheet according to claim 6, wherein In step S1, the antioxidant, light stabilizer, and linear low-density polyethylene are mixed in a high-speed mixer for 5 minutes.

8. The method of claim 6, wherein the puncture-resistant, tear-resistant, waterproof sheet is prepared by the steps of: In step S2, the antioxidant premix is ​​melt-blended in an underwater pelletizer, and the melt extrusion temperature is 190~200℃ and the rotation speed is 200~350r / min; the melt extrusion equipment is a counter-rotating twin-screw extruder.

9. The method of claim 6, wherein the puncture-resistant, tear-resistant, waterproof sheet is prepared by the steps of: In step S3, the antioxidant masterbatch, ethylene-vinyl acetate copolymer, ultra-high molecular weight polyethylene, modified polypropylene, ethylene-octene copolymer, silica particles and compatibilizer are mixed in a mixer for 10 minutes.

10. The method of claim 6, wherein the puncture-resistant, tear-resistant, waterproof sheet is prepared by the steps of: In step S4, the operating temperature of the counter-rotating twin-screw extruder is 200~220℃, and the screw speed is 300r / min; The temperature of the cooling calendering roller is 55±5℃, and the diameter of the cooling calendering roller is 600mm.

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