A polymer waterproof membrane and its manufacturing process

Abstract

This invention discloses a polymer waterproof membrane and its preparation process, relating to the field of waterproof membrane technology. The membrane comprises an upper layer, a middle layer, and a lower layer stacked sequentially. The upper and lower layers are composed of the same raw materials, including the following parts by weight: 100-140 parts modified polyurethane, 5-10 parts polytetrahydrofuran glycol, 4-8 parts inorganic filler, and 4-8 parts stabilizer. The modified polyurethane includes the following parts by weight: 60-80 parts polyurethane, 20-30 parts cashew nut shell powder, 15-20 parts nano-silica, 25-30 parts trimethylchlorosilane, and 5-10 parts calcium carbonate. The middle layer includes the following parts by weight: 45-60 parts modified hydration composition and 55-60 parts anhydrous adhesive. The use of cashew nut shell powder to modify the polyurethane not only improves its strength and heat resistance but also significantly enhances its hydrophobicity. Simultaneously, through the hydration reaction of fly ash in the modified hydration composition and the gelation reaction of strongly alkaline anions, water intrusion into the lower layer can be prevented even when cracks appear in the upper layer.

Description

Technical Field

[0001] This invention relates to the field of waterproof membrane technology, specifically to a polymer waterproof membrane and its manufacturing process. Background Technology

[0002] Waterproof membrane is a flexible building material that can be rolled up, mainly used for waterproofing projects in building walls, roofs, tunnels, highways, landfills, and other locations. As a key material for a leak-proof connection between the foundation and the building, waterproof membrane is the first line of defense in the entire waterproofing project, playing a crucial role in the overall waterproofing effect.

[0003] Existing waterproof membranes are mainly classified according to their main constituent materials and the type of substrate. Based on the main constituent materials, waterproof membranes can be divided into bitumen waterproof membranes, polymer-modified bitumen waterproof membranes, and synthetic polymer waterproof membranes, etc.; based on the type of substrate, they can be divided into substrate-free membranes, paper-based membranes, fiberglass-based membranes, glass cloth-based membranes, and polyethylene-based membranes, etc.

[0004] Polymer waterproof membranes are waterproof membranes made from synthetic rubber, synthetic resin, or a blend of both as base materials, with the addition of appropriate additives and fillers, processed through compounding, calendering, or extrusion. Under temperatures above 100℃, the membrane does not flow or generate concentrated air bubbles, exhibiting excellent heat resistance. Its tear strength is generally above 20KN / m, demonstrating excellent crack resistance and the ability to withstand significant external forces. Its tensile strength is generally above 3MPa, with some reaching around 10MPa, meeting the practical needs of handling, construction, and application. Due to their superior performance, polymer waterproof membranes are widely used in the waterproofing field.

[0005] However, while existing polymer waterproof membranes can achieve good waterproofing under natural conditions, they are prone to damage and cracking when subjected to external forces, such as strong winds blowing sharp objects onto the surface or accidental scratches. Furthermore, cracking will inevitably occur when the membrane reaches the end of its service life, significantly reducing its waterproofing effectiveness.

[0006] Based on this, the present invention aims to provide a polymer waterproof membrane that not only has extremely high water resistance, strength and tensile properties, but also whose waterproof effect is not affected after the surface of the membrane cracks. Summary of the Invention

[0007] The purpose of this invention is to provide a polymer waterproof membrane and its manufacturing process; and to solve the following technical problems:

[0008] How can waterproof membranes maintain excellent waterproof performance even after surface cracking, while possessing extremely high water resistance, strength, and tensile properties?

[0009] The objective of this invention can be achieved through the following technical solutions:

[0010] In a first aspect, the present invention discloses a polymer waterproof membrane, comprising an upper layer, a middle layer and a lower layer stacked sequentially; the upper layer and the lower layer are composed of the same raw materials, including the following raw materials in parts by weight: 100-140 parts of modified polyurethane, 5-10 parts of polytetrahydrofuran diol, 4-8 parts of inorganic filler and 4-8 parts of stabilizer.

[0011] Preferably, the modified polyurethane comprises 110-130 parts, polytetrahydrofuran diol comprises 6-9 parts, inorganic filler comprises 5-7 parts, and stabilizer comprises 5-7 parts; more preferably, the modified polyurethane comprises 120 parts, polytetrahydrofuran diol comprises 8 parts, inorganic filler comprises 6 parts, and stabilizer comprises 6 parts.

[0012] The modified polyurethane includes the following raw materials in parts by weight: 60-80 parts polyurethane, 20-30 parts cashew phenol, 15-20 parts nano silica, 25-30 parts trimethylchlorosilane, and 5-10 parts calcium carbonate.

[0013] Preferably, the polyurethane comprises 65-75 parts, cashew nut shell powder comprises 23-28 parts, nano-silica comprises 17-19 parts, trimethylchlorosilane comprises 27-29 parts, and calcium carbonate comprises 7-9 parts; more preferably, the polyurethane comprises 70 parts, cashew nut shell powder comprises 25 parts, nano-silica comprises 18 parts, trimethylchlorosilane comprises 28 parts, and calcium carbonate comprises 8 parts.

[0014] The middle layer comprises the following raw materials in parts by weight: 45-60 parts of modified hydration composition and 55-60 parts of anhydrous adhesive;

[0015] Preferably, the modified hydration composition comprises 50-55 parts and the anhydrous adhesive comprises 56-59 parts; more preferably, the modified hydration composition comprises 53 parts and the anhydrous adhesive comprises 58 parts.

[0016] The modified hydration composition comprises a strongly basic anion exchange resin and fly ash in a mass ratio of 1:(3-6), preferably 1:(4-5), more preferably 1:4.5.

[0017] In a further technical solution of the present invention, the method for preparing modified polyurethane is as follows:

[0018] S1: After mixing polyurethane and cashew phenol evenly, heat to 80-100℃, then add nano silica, and stir at a constant speed for 1-2 hours while maintaining the temperature to obtain material A;

[0019] S2: Cool material A to 40-50℃, then add trimethylchlorosilane to material A and stir thoroughly. Finally, add calcium carbonate in 2-3 portions and maintain the temperature while stirring for 2-4 hours. Skim off any foam to obtain the modified polyurethane.

[0020] Polyurethane was modified using cashew phenol, which contains a large amount of bio-based aromatic polyols with high hydroxyl values ​​and a large number of hydroxyl groups. When mixed with polyurethane, a small portion of the hydroxyl groups act as functional groups for cross-linking and curing, leading to an increase in the cross-linking density of the polyurethane. This improves the stiffness and hardness of the polyurethane, prevents thermal decomposition and thermal deformation, and enhances its heat resistance. However, the increased number of hydroxyl groups also makes the material more hydrophilic. Therefore, trimethylchlorosilane was subsequently added to react with most of the hydroxyl groups in the cashew phenol to undergo alkylation. The resulting silanized product has low polarity and surface tension, thus exhibiting significant hydrophobicity. This hydrophobic effect is far greater than the hydrophilic effect brought by the hydroxyl groups combined with the polyurethane. Therefore, the modified polyurethane not only improves its strength and heat resistance but also greatly enhances its hydrophobicity.

[0021] In a further technical solution of the present invention, the modified hydration composition is prepared by: crushing a strong base anion exchange resin and fly ash into powder according to a certain ratio and mixing them evenly to obtain the modified hydration composition; preferably, the strong base anion exchange resin is a strong base quaternary ammonium type I anion exchange resin, model 201.

[0022] Strongly basic anion exchange resins have smooth surfaces, no large capillaries inside the granules, and a large number of negatively charged anionic functional groups on their surfaces, enabling them to effectively adsorb positively charged ions and molecules. Fly ash particles, on the other hand, have a porous honeycomb structure with a large specific surface area and high adsorption activity. Therefore, when strongly basic anion exchange resins and fly ash are mixed, they will adsorb each other. Since the mass ratio of strongly basic anion exchange resin to fly ash is maintained at 1:(3-6), multiple fly ash particles will adhere to the surface of one strongly basic anion exchange resin particle, forming a resin-fly ash composite with a rough surface. At the same time, the strongly basic anion exchange resin contains strongly basic groups, such as quaternary ammonium groups (NR3O), so the modified hydration composition is generally alkaline.

[0023] In a further technical solution of the present invention, the anhydrous adhesive comprises the following raw materials in parts by weight: 75-85 parts sodium silicate, 2-10 parts urea, 0.5-3 parts oligosaccharide, 0.1-1 parts potassium dichromate, 1-4 parts magnesium sulfate, and 0-8 parts kaolin.

[0024] Preferably, the composition comprises 78-83 parts sodium silicate, 4-8 parts urea, 1-2.5 parts oligosaccharide, 0.3-0.8 parts potassium dichromate, 2-3.5 parts magnesium sulfate, and 2-6 parts kaolin; more preferably, the composition comprises 80 parts sodium silicate, 6 parts urea, 2 parts oligosaccharide, 0.5 parts potassium dichromate, 3 parts magnesium sulfate, and 4 parts kaolin.

[0025] In a further technical solution of the present invention, the method for preparing the anhydrous adhesive is as follows:

[0026] S1: Add an appropriate amount of water to sodium silicate and stir thoroughly to prepare a sodium silicate solution with a mass concentration of 35% to 45%; add an appropriate amount of water to urea and stir thoroughly to prepare a urea solution; add an appropriate amount of water to oligosaccharides and stir thoroughly to prepare an oligosaccharide solution.

[0027] S2: Transfer the sodium silicate solution to a stirrer, then add the urea solution and oligosaccharide solution, and then turn on the stirrer to mix until evenly combined;

[0028] S3: Continue to add potassium dichromate and magnesium sulfate to the mixer and stir until uniform. Then add kaolin and stir until uniform to obtain anhydrous adhesive.

[0029] In a further embodiment of the present invention, the mass fraction of the urea solution is 65% to 85%, preferably 70% to 80%, more preferably 75%; and the mass fraction of the oligosaccharide is 80% to 85%, preferably 81% to 84%, more preferably 83%.

[0030] In a further technical solution of the present invention, the inorganic filler is one or a mixture of several of calcium carbonate, talc, wood flour, and cellulose;

[0031] Preferably, the inorganic filler is a mixture of calcium carbonate and talc.

[0032] In a further technical solution of the present invention, the stabilizer is one or a mixture of several of zinc stearate, calcium stearate, paraffin, dibenzoylmethane, and dipentaerythritol.

[0033] Preferably, the stabilizer is a mixture of zinc stearate and calcium stearate.

[0034] Secondly, the present invention also discloses a preparation process for a polymer waterproof membrane as described above, comprising the following steps:

[0035] (1) Preparation of upper and lower layer materials

[0036] Modified polyurethane, polytetrahydrofuran diol, inorganic filler and stabilizer are added to a mixer in proportion and mixed thoroughly to obtain mixture one. Mixture one is transferred to a melt blending equipment and heated at 130-140℃ for 3-4 hours. After being converted to a molten state, it is stirred thoroughly to obtain mixture two. Mixture two is transferred to an extruder and extruded into sheets to obtain upper and lower materials.

[0037] Polytetrahydrofuran glycol, as a polyether polymer, is characterized by high molecular weight, low-temperature flexibility, and chemical resistance. Its molecular weight is usually between 2,000 and 4,000. This high molecular weight helps to form strong and tough molecular chains in polyurethane. The regularity of the molecular chain segments makes it easy for polytetrahydrofuran glycol to form an ordered crystalline structure in the polyurethane system. This structure can also improve the strength and stability of polyurethane.

[0038] (2) Preparation of the middle layer material

[0039] The modified hydration composition and anhydrous adhesive were added to a mixer in proportion and stirred until homogeneous to obtain the middle layer material.

[0040] To avoid hydration reaction in the modified hydration composition, an anhydrous adhesive is selected for mixing with it. After mixing, the modified hydration composition has a certain degree of viscosity.

[0041] (3) Preparation of polymer waterproof membrane

[0042] The lower layer material is laid flat on the bottom, the middle layer material is evenly applied on the lower layer material, and then the upper layer material is covered on the middle layer material. Finally, the upper layer material, the middle layer material and the lower layer material are hot-pressed together to obtain the roll material precursor. The roll material precursor is then pressed thin by a calender and finally cooled and shaped to obtain the polymer waterproof roll material.

[0043] The beneficial effects of this invention are:

[0044] (1) The waterproof membrane of the present invention contains modified polyurethane, which is modified by cashew phenol. Cashew phenol contains a large amount of bio-based aromatic polyols with high hydroxyl value and large number of hydroxyl groups. After mixing with polyurethane, a small portion of the hydroxyl groups act as functional groups for cross-linking and curing, which leads to an increase in the cross-linking density of polyurethane, thereby improving the stiffness and hardness of polyurethane and preventing thermal decomposition and thermal deformation, thus improving heat resistance. However, the increase of hydroxyl groups also makes the material more hydrophilic. Therefore, trimethylchlorosilane is subsequently added to react with most of the hydroxyl groups in cashew phenol to undergo alkyl silane reaction. The silanized product has low polarity and surface tension, thus exhibiting significant hydrophobicity. This hydrophobic effect is much greater than the hydrophilic effect brought by the hydroxyl groups combined with polyurethane. Therefore, the modified polyurethane not only improves the strength and heat resistance, but also greatly improves the hydrophobicity.

[0045] (2) The waterproof membrane of the present invention contains polytetrahydrofuran diol. As a polyether polymer, polytetrahydrofuran diol has the characteristics of high molecular weight, low temperature softness and chemical corrosion resistance. Its molecular weight is usually between 2000 and 4000. This high molecular weight helps to form strong and tough molecular chains in polyurethane. The regularity of the molecular chain segments makes it easy for polytetrahydrofuran diol to form an ordered crystalline structure in the polyurethane system. This structure can also improve the strength and stability of polyurethane.

[0046] (3) The waterproof membrane of the present invention is provided with three layers. The strength of the upper and lower layers is relatively high, but the tensile properties are not high. This is because the increase in crosslinking density will restrict the movement of polyurethane molecular chains, which will adversely affect its tensile properties. Therefore, the waterproof membrane is made into three layers: upper, middle and lower. Since the middle layer is composed only of anhydrous adhesive and modified hydration composition, its tensile properties are relatively large, which can better compensate for the overall tensile properties of the membrane and greatly reduce the influence of modified polyurethane on its tensile properties. At the same time, since the resin-fly ash composite in the modified hydration composition of the middle layer has an extremely rough surface, it will form an interlocking structure with the bonding surface of the upper and lower layers during hot pressing, which makes the bonding force between the middle layer and the upper and lower layers greater, avoids the delamination phenomenon, and can also better compensate for the overall tensile properties of the membrane, thereby obtaining a waterproof membrane with good strength and tensile properties.

[0047] (4) When cracks appear on the upper surface of the waterproof membrane of the present invention, water droplets will carry calcium carbonate from the modified polyurethane into the middle layer once they enter the cracks, creating an alkaline environment for the middle layer. The fly ash in the modified hydration composition will undergo a hydration reaction with water under alkaline conditions. At the same time, the quaternary ammonium group ~NR3O of the strong base anion exchange resin in the modified hydration composition will further promote the generation of the alkaline environment. Therefore, water droplets will undergo a hydration reaction with fly ash. The active ingredients in fly ash react with water and calcium carbonate to generate gel-like, filamentous, fibrous and needle-like hydrated calcium silicate. These hydration products intertwine and grow together, and are bonded together with the reacted glass body as the skeleton to form a composite. It continuously expands along the cracks in the upper layer, not only consuming the intruding water, but also filling the cracks. At the same time, the strong base anion exchange resin will swell into a gel after contact with water, further preventing water from intruding into the lower layer. Therefore, even if cracks appear in the upper layer, the membrane can still play an excellent waterproof role. Detailed Implementation

[0048] The present invention will now be described in further detail with reference to specific embodiments. The given embodiments are merely illustrative of the invention and not intended to limit its scope. The embodiments provided below can serve as a guide for further improvements by those skilled in the art and do not constitute a limitation on the invention in any way.

[0049] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Unless otherwise specified, the materials and reagents used in the following examples are commercially available.

[0050] Example 1

[0051] Preparation of modified polyurethane:

[0052] Add 700g of polyurethane and 250g of cashew nut powder to a magnetically heated stirrer, stir until homogeneous, and heat to 90°C. Then add 180g of nano-silica and stir at a constant speed of 200rpm for 1.5h. Then cool down to 45°C, add 280g of trimethylchlorosilane and stir until homogeneous. Finally, add a total of 80g of calcium carbonate in three batches (25g each in the first and second batches, and 30g in the third batch). Stir at a constant speed of 200rpm at 45°C for 3h. Skim off the foam on the surface to obtain the modified polyurethane.

[0053] Example 2

[0054] Preparation of modified polyurethane:

[0055] Add 140g of polyurethane and 50g of cashew nut powder to a magnetically heated stirrer, stir until homogeneous, and heat to 90°C. Then add 36g of nano-silica and stir at a constant speed of 200rpm for 1.5h. Then cool down to 45°C and add a total of 16g ​​of calcium carbonate in three batches (5g each in the first and second batches, and 6g in the third batch). Stir at a constant speed of 200rpm at 45°C for 3h. Skim off the foam on the surface to obtain the modified polyurethane.

[0056] Example 3

[0057] Preparation of modified polyurethane:

[0058] Add 140g of polyurethane to a magnetically heated stirrer and heat to 90℃. Then add 36g of nano-silica and stir at a constant speed of 200rpm for 1.5h. Then cool down to 45℃ and add 56g of trimethylchlorosilane and stir evenly. Finally, add a total of 16g ​​of calcium carbonate in three batches (5g each in the first and second batches, and 6g in the third batch). Stir at a constant speed of 200rpm at 45℃ for 3h. Skim off the foam on the surface to obtain the modified polyurethane.

[0059] Example 4

[0060] Preparation of modified polyurethane:

[0061] Add 140g of polyurethane and 50g of cashew phenol to a magnetically heated stirrer, stir evenly, and heat to 90°C. Then add 36g of nano silica and stir at a constant speed of 200rpm for 1.5h. Then cool down to 45°C, add 56g of trimethylchlorosilane and stir evenly. Skim off the foam on the top layer to obtain the modified polyurethane.

[0062] Example 5

[0063] Preparation of modified hydration composition:

[0064] 20g of strong base quaternary ammonium type I anion exchange resin (model: 201) and 90g of fly ash were respectively put into a crusher and ground into powder. Then they were added together into a beaker and stirred evenly to obtain the modified hydration composition.

[0065] Example 6

[0066] Preparation of anhydrous adhesives:

[0067] Add 160g of sodium silicate and 400g of purified water to the first beaker, and stir with a glass rod to obtain a sodium silicate solution. Add 12g of urea and 16g of purified water to the second beaker, and stir with a glass rod to obtain a urea solution. Add 4g of oligosaccharide and 5g of purified water to the third beaker, and stir with a glass rod to obtain an oligosaccharide solution. Add the sodium silicate solution, urea solution, and oligosaccharide solution to a stirrer and stir for 30 minutes. Then add 1g of potassium dichromate and 6g of magnesium sulfate to the stirrer and continue stirring for 20 minutes. Finally, add 8g of kaolin and stir for 10 minutes to obtain an anhydrous adhesive.

[0068] Example 7

[0069] Preparation of waterproof membrane:

[0070] (1) Preparation of upper and lower layer materials

[0071] 100g of the modified polyurethane prepared in Example 1, 5g of polytetrahydrofuran, 2g of calcium carbonate, 2g of talc, 2g of zinc stearate, and 2g of calcium stearate were added to a mixer and mixed evenly. Then the mixture was transferred to an internal mixer, and the internal mixer temperature was set to 130°C and the heating time was set to 4h. After heating, a molten mixture was obtained. The molten mixture was transferred to an extruder and extruded into sheets. After cutting, upper and lower layer materials with dimensions of 50×30×2mm were obtained.

[0072] (2) Preparation of middle layer material

[0073] 45g of the modified hydration composition prepared in Example 5 and 55g of the anhydrous adhesive prepared in Example 6 were added together to a mixer and stirred to obtain the middle layer material.

[0074] (3) Combination of upper, middle and lower layer materials

[0075] Lay the bottom layer material flat, apply a 2.5mm thick middle layer material evenly on the bottom layer material, then cover the middle layer material with the top layer material, and finally use a hot press to hot press the top, middle and bottom layers together to obtain the roll material precursor. The roll material precursor is then pressed thin by a calender and finally cooled and shaped to obtain the polymer waterproof roll material.

[0076] Example 8

[0077] Preparation of waterproof membrane:

[0078] (1) Preparation of upper and lower layer materials

[0079] 110g of the modified polyurethane prepared in Example 1, 6g of polytetrahydrofuran, 2g of calcium carbonate, 3g of talc, 2g of zinc stearate, and 3g of calcium stearate were added to a mixer and mixed evenly. Then the mixture was transferred to an internal mixer, and the internal mixer temperature was set to 132℃ and the heating time was set to 3.8h. After heating, a molten mixture was obtained. The molten mixture was transferred to an extruder and extruded into sheets. After cutting, upper and lower layer materials with dimensions of 50×30×2mm were obtained.

[0080] (2) Preparation of middle layer material

[0081] 53g of the modified hydration composition prepared in Example 5 and 58g of the anhydrous adhesive prepared in Example 6 were added together to a mixer and stirred to obtain the middle layer material.

[0082] (3) Combination of upper, middle and lower layer materials

[0083] Lay the bottom layer material flat, apply a 2.5mm thick middle layer material evenly on the bottom layer material, then cover the middle layer material with the top layer material, and finally use a hot press to hot press the top, middle and bottom layers together to obtain the roll material precursor. The roll material precursor is then pressed thin by a calender and finally cooled and shaped to obtain the polymer waterproof roll material.

[0084] Example 9

[0085] Preparation of waterproof membrane:

[0086] (1) Preparation of upper and lower layer materials

[0087] 120g of the modified polyurethane prepared in Example 1, 8g of polytetrahydrofuran, 3g of calcium carbonate, 3g of talc, 3g of zinc stearate, and 3g of calcium stearate were added to a mixer and mixed evenly. Then the mixture was transferred to an internal mixer, and the internal mixer temperature was set to 135°C and the heating time was set to 3.5h. After heating, a molten mixture was obtained. The molten mixture was transferred to an extruder and extruded into sheets. After cutting, upper and lower layer materials with dimensions of 50×30×2mm were obtained.

[0088] (2) Preparation of middle layer material

[0089] 53g of the modified hydration composition prepared in Example 5 and 58g of the anhydrous adhesive prepared in Example 6 were added together to a mixer and stirred to obtain the middle layer material.

[0090] (3) Combination of upper, middle and lower layer materials

[0091] Lay the bottom layer material flat, apply a 2.5mm thick middle layer material evenly on the bottom layer material, then cover the middle layer material with the top layer material, and finally use a hot press to hot press the top, middle and bottom layers together to obtain the roll material precursor. The roll material precursor is then pressed thin by a calender and finally cooled and shaped to obtain the polymer waterproof roll material.

[0092] Example 10

[0093] Preparation of waterproof membrane:

[0094] (1) Preparation of upper and lower layer materials

[0095] 130g of the modified polyurethane prepared in Example 1, 9g of polytetrahydrofuran, 3g of calcium carbonate, 4g of talc, 3g of zinc stearate, and 4g of calcium stearate were added to a mixer and mixed evenly. Then, the mixture was transferred to an internal mixer, and the internal mixer temperature was set to 138°C and the heating time was set to 3.2h. After heating, a molten mixture was obtained. The molten mixture was transferred to an extruder and extruded into sheets. After cutting, upper and lower layer materials with dimensions of 50×30×2mm were obtained.

[0096] (2) Preparation of middle layer material

[0097] 55g of the modified hydration composition prepared in Example 5 and 59g of the anhydrous adhesive prepared in Example 6 were added together to a mixer and stirred to obtain the middle layer material.

[0098] (3) Combination of upper, middle and lower layer materials

[0099] Lay the bottom layer material flat, apply a 2.5mm thick middle layer material evenly on the bottom layer material, then cover the middle layer material with the top layer material, and finally use a hot press to hot press the top, middle and bottom layers together to obtain the roll material precursor. The roll material precursor is then pressed thin by a calender and finally cooled and shaped to obtain the polymer waterproof roll material.

[0100] Example 11

[0101] Preparation of waterproof membrane:

[0102] (1) Preparation of upper and lower layer materials

[0103] 140g of the modified polyurethane prepared in Example 1, 10g of polytetrahydrofuran, 4g of calcium carbonate, 4g of talc, 4g of zinc stearate, and 4g of calcium stearate were added to a mixer and mixed evenly. Then the mixture was transferred to an internal mixer, and the internal mixer temperature was set to 140℃ and the heating time was set to 3h. After heating, a molten mixture was obtained. The molten mixture was transferred to an extruder and extruded into sheets. After cutting, upper and lower layer materials with dimensions of 50×30×2mm were obtained.

[0104] (2) Preparation of middle layer material

[0105] 60g of the modified hydration composition prepared in Example 5 and 60g of the anhydrous adhesive prepared in Example 6 were added together to a mixer and stirred to obtain the middle layer material.

[0106] (3) Combination of upper, middle and lower layer materials

[0107] Lay the bottom layer material flat, apply a 2.5mm thick middle layer material evenly on the bottom layer material, then cover the middle layer material with the top layer material, and finally use a hot press to hot press the top, middle and bottom layers together to obtain the roll material precursor. The roll material precursor is then pressed thin by a calender and finally cooled and shaped to obtain the polymer waterproof roll material.

[0108] Comparative Example 1

[0109] Compared with Example 9, the only difference is that when preparing the upper and lower layer materials, the modified polyurethane obtained in Example 1 is replaced with the polyurethane obtained in Example 2, and finally a polymer waterproof membrane is obtained.

[0110] Comparative Example 2

[0111] Compared with Example 9, the only difference is that when preparing the upper and lower layer materials, the modified polyurethane obtained in Example 1 is replaced with the polyurethane obtained in Example 3, and finally a polymer waterproof membrane is obtained.

[0112] Comparative Example 3

[0113] Compared with Example 9, the only difference is that when preparing the upper and lower layer materials, the modified polyurethane obtained in Example 1 is replaced with ordinary polyurethane, and finally a polymer waterproof membrane is obtained.

[0114] Comparative Example 4

[0115] Compared with Example 9, the only difference is that when preparing the upper and lower layer materials, the modified polyurethane obtained in Example 1 is replaced with the polyurethane obtained in Example 4, and finally a polymer waterproof membrane is obtained.

[0116] Comparative Example 5

[0117] Compared with Example 9, the only difference is that when preparing the middle layer material, the modified hydration composition obtained in Example 5 is replaced with fly ash, and finally a polymer waterproof membrane is obtained.

[0118] Comparative Example 6

[0119] Compared with Example 9, the only difference is in two points. First, when preparing the upper and lower layer materials, the modified polyurethane prepared in Example 1 is replaced with the polyurethane prepared in Example 4. Second, when preparing the middle layer material, the modified hydration composition prepared in Example 5 is replaced with fly ash, and finally a polymer waterproof membrane is obtained.

[0120] The polymer waterproof membranes prepared in Examples 7-11 and Comparative Examples 1-3 were subjected to performance tests, including impact resistance, tensile properties, and water absorption. The test methods were in accordance with the following national standard methods:

[0121] Impact resistance: GB / T 328.24~2007;

[0122] Tensile properties: GB / T 328.9~2007;

[0123] Water absorption: GB / T 328.27~2007.

[0124] The test results are listed in Table 1, as follows:

[0125] Table 1

[0126]

[0127] Analysis of the data in Table 1 shows that the polymer waterproof membranes of Examples 7-11 of this invention have better impact resistance, slightly higher tensile strength, and stronger water absorption rate compared to the polymer waterproof membranes of Comparative Examples 1-3.

[0128] The waterproof performance of the polymer waterproof membranes prepared in Examples 7-11 and Comparative Examples 4-6 was tested using the following methods:

[0129] Make a 5cm x 5cm cross-shaped slit in the top layer of the polymer waterproof membrane with a knife. Place 20 sheets of absorbent paper (30cm x 30cm) stacked on a table. Lay the polymer waterproof membrane flat on the top sheet of absorbent paper, with the cross-shaped slit centered on the absorbent paper. Then place a 20cm x 20cm x 30cm square frame with openings at the top and bottom on the polymer waterproof membrane, with the cross-shaped slit centered on the frame. Use waterproof adhesive to bond the bottom of the frame to the surface of the polymer waterproof membrane. After it dries, fill the frame with water at 40℃. Let it stand for 12 hours, then drain the water and remove the frame along with the polymer waterproof membrane. Take 20 sheets of absorbent paper and observe how many sheets are wetted from top to bottom. The more sheets of absorbent paper that are wetted, the worse the waterproof effect of the polymer waterproof membrane, and vice versa.

[0130] The test results are listed in Table 2, as follows:

[0131] Table 2

[0132]

[0133] Analysis of the data in Table 2 shows that the polymer waterproof membranes of Examples 7-11 of the present invention still have excellent waterproofing effect after the upper layer cracks, compared with the polymer waterproof membranes of Comparative Examples 4-6.

[0134] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. A polymer waterproof membrane, characterized in that, Includes upper, middle, and lower layers; The upper and lower layers are composed of the same raw materials, including the following parts by weight: 100-140 parts of modified polyurethane, 5-10 parts of polytetrahydrofuran diol, 4-8 parts of inorganic filler, and 4-8 parts of stabilizer. The modified polyurethane comprises the following raw materials in parts by weight: 60-80 parts polyurethane, 20-30 parts cashew phenol, 15-20 parts nano silica, 25-30 parts trimethylchlorosilane, and 5-10 parts calcium carbonate. The middle layer comprises the following raw materials in parts by weight: 45-60 parts of modified hydration composition and 55-60 parts of anhydrous adhesive; the modified hydration composition comprises a strong basic anion exchange resin and fly ash in a mass ratio of 1:(3-6). The anhydrous adhesive comprises the following raw materials in parts by weight: 75-85 parts sodium silicate, 2-10 parts urea, 0.5-3 parts oligosaccharide, 0.1-1 parts potassium dichromate, 1-4 parts magnesium sulfate, and 0-8 parts kaolin.

2. The polymer waterproof membrane according to claim 1, characterized in that, The modified polyurethane is prepared by: S1: After mixing polyurethane and cashew phenol evenly, heat to 80-100℃, then add nano silica, and stir at a constant speed for 1-2 hours while maintaining the temperature to obtain material A; S2: Cool material A to 40-50℃, then add trimethylchlorosilane to material A and stir thoroughly. Finally, add calcium carbonate in 2-3 portions and maintain the temperature while stirring for 2-4 hours. Skim off any foam to obtain the modified polyurethane.

3. The polymer waterproof membrane according to claim 2, characterized in that, The modified hydration composition is prepared by crushing a strong basic anion exchange resin and fly ash into powder according to a certain ratio and mixing them evenly to obtain the modified hydration composition.

4. The polymer waterproof membrane according to claim 1, characterized in that, The inorganic filler is one or a mixture of calcium carbonate and talc.

5. The polymer waterproof membrane according to claim 1, characterized in that, The stabilizer is one or a mixture of several of the following: zinc stearate, calcium stearate, paraffin, dibenzoylmethane, and dipentaerythritol.

6. A preparation process for the polymer waterproof membrane according to any one of claims 1 to 5, characterized in that, Includes the following steps: (1) Preparation of upper and lower layer materials Modified polyurethane, polytetrahydrofuran diol, inorganic filler and stabilizer are added to a mixer in proportion and mixed thoroughly to obtain mixture one. Mixture one is transferred to a melt blending equipment, heated to a molten state and stirred thoroughly to obtain mixture two. Mixture two is transferred to an extruder and extruded into sheets to obtain upper and lower materials. (2) Preparation of intermediate layer material The modified hydration composition and anhydrous adhesive were added to a mixer in proportion and stirred until homogeneous to obtain the middle layer material. (3) Preparation of polymer waterproof membrane The lower layer material is laid flat on the bottom, the middle layer material is evenly applied on the lower layer material, and then the upper layer material is covered on the middle layer material. Finally, the upper layer material, the middle layer material and the lower layer material are hot-pressed together to obtain the roll material precursor. The roll material precursor is then pressed thin by a calender and finally cooled and shaped to obtain the polymer waterproof roll material.

7. The preparation process of the polymer waterproof membrane according to claim 6, characterized in that, When preparing the upper and lower layer materials, the temperature of the melt blending equipment is 130-140℃ and the stirring time is 3-4h.

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