Polymerized polypropylene waterproofing membrane and preparation method thereof

Abstract

The application belongs to the technical field of building materials, and discloses a high-molecular polypropylene waterproof coiled material and a preparation method. The high-molecular polypropylene waterproof coiled material comprises the following raw materials: base pitch, tackifying resin, SBS, acrylic copolymer, additive, filler, PET fiber and root inhibitor. The additive comprises pyromellitic dianhydride and isocyanuric acid triglycidyl ester. In the application, different additives are compounded, and the acrylic copolymer, inorganic filler and PET fiber are added at the same time, which interact with the pitch to form a uniform and stable network structure, so that the prepared modified pitch layer has high impact resistance and high weather resistance. In the application, the polyacrylic acid sodium and the ceramsite are compounded in the polyethylene layer to further improve the waterproofness of the high-molecular polypropylene waterproof coiled material. The high-molecular polypropylene waterproof coiled material prepared in the application has good waterproofness, impact resistance, mechanical properties and good puncture resistance.

Description

Technical Field

[0001] This application relates to the field of building materials technology, and in particular to a polymer polypropylene waterproof membrane and its preparation method. Background Technology

[0002] Waterproof membranes are primarily used in building walls, roofs, tunnels, highways, landfills, and other applications to resist external rainwater and groundwater seepage. These flexible, rollable building materials serve as the first line of defense between the foundation and the building structure, preventing leakage and playing a crucial role in the overall waterproofing of the project. Currently, the most common polymer-synthetic waterproof membrane is a polyethylene-polypropylene composite waterproof membrane. Polypropylene, also known as polypropylene fiber, is a synthetic fiber made from propylene, a byproduct of petroleum refining, and isotactic polypropylene fiber, which has high waterproofing performance. Waterproof membranes require good water resistance, stability to temperature changes (no flow, bubbling, or movement at high temperatures; no brittleness at low temperatures), certain mechanical strength, elongation, and fracture resistance, as well as a certain degree of flexibility and aging resistance. In existing technologies, polypropylene composite waterproof membranes are usually made of a polyethylene sheet in the middle and polypropylene non-woven fabric on both sides. The resulting waterproof membrane has low strength, poor weather resistance, and short service life. Moreover, when used in underground waterproofing projects, it is easily punctured by stones in the concrete of the protective layer above the waterproof membrane, thus losing the performance that the waterproof membrane should have. Summary of the Invention

[0003] To address the aforementioned technical problems and develop a waterproof membrane with good waterproof performance, impact resistance, and mechanical properties, as well as scratch and root penetration resistance, this application provides a polymer polypropylene waterproof membrane and its preparation method.

[0004] In a first aspect, this application provides a polymeric polypropylene waterproof membrane, which comprises, from top to bottom, a first polypropylene nonwoven fabric layer, a modified bitumen layer, a metal-based base layer, a polyethylene layer, and a second polypropylene nonwoven fabric layer; the modified bitumen layer comprises the following raw materials in parts by weight: 70-120 parts of base bitumen, 4-6 parts of tackifying resin, 6-10 parts of SBS, 8-14 parts of acrylic copolymer, 2-4 parts of additives, 11-18 parts of filler, 2-5 parts of PET fiber, and 2-3 parts of root inhibitor; the additives include pyromellitic dianhydride and triglycidyl isocyanate.

[0005] Furthermore, the additive comprises pyromellitic dianhydride and triglycidyl isocyanurate in a weight ratio of 1:1-2.

[0006] By adopting the above technical solution, the additives selected are pyromellitic dianhydride and triglycidyl isocyanate. Pyromellitic dianhydride, which contains a multifunctional anhydride structure, reacts with active groups such as hydroxyl and carboxyl groups in asphalt. Triglycidyl isocyanate, which contains a multifunctional isocyanate group, reacts with active groups such as hydroxyl and carboxyl groups in asphalt, thereby forming a stable network matrix structure. This reduces the flocculation effect of large molecules in asphalt or breaks up previously stacked asphalt aggregates, reducing the degree of asphalt coagulation and increasing the dispersibility of asphalt, thus increasing the stability and high-temperature resistance of modified asphalt. The network structure of the asphalt matrix allows inorganic fillers to be uniformly dispersed within it, which can effectively improve the overall impact resistance of the modified asphalt layer. Secondly, the additives can also react with the terminal hydroxyl or carboxyl groups of the molecular chains of PET fibers, thereby promoting cross-linking between asphalt and PET fibers and between PET fibers to form more branched structures, thus improving the overall strength of the modified asphalt layer.

[0007] Furthermore, the filler comprises talc powder and modified wollastonite in a weight ratio of 1:3-6.

[0008] Furthermore, the preparation method of the modified wollastonite includes the following steps: preparing a suspension of wollastonite in a solvent, adding tung oil acid, heating to 70-80℃, sonicating, filtering to collect the filter residue, washing, drying, and obtaining modified wollastonite, wherein the weight ratio of wollastonite to tung oil acid is 10-15:1.

[0009] By adopting the above technical solution, the talc powder with a small particle size in the filler can act as a nucleating agent during the melting process of asphalt, promoting the uniform dispersion of large air bubbles in the asphalt gaps into numerous small air bubbles, thereby increasing the dispersibility and stability of the asphalt. Wollastonite is a needle-shaped silicate material with good mechanical and fire-resistant properties. Tung oil acid is used as a surface modifier to modify wollastonite, which can prevent the local agglomeration of wollastonite powder in the asphalt matrix material. It can also improve the poor bonding between the needle-shaped structure of wollastonite and the asphalt matrix, as well as the situation where a large number of pores and gaps appear around the powder and on the matrix, thereby improving the compatibility between wollastonite and the asphalt matrix material.

[0010] Furthermore, the acrylic copolymers include one or more of the following: methyl acrylate-acrylic copolymer, methyl methacrylate-acrylic copolymer, ethyl acrylate-acrylic copolymer, hydroxyethyl acrylate-acrylic copolymer, hydroxypropyl acrylate-acrylic copolymer, n-butyl acrylate-acrylic copolymer, isooctyl acrylate-acrylic copolymer, and glycidyl methacrylate-acrylic copolymer.

[0011] By adopting the above technical solution, acrylic copolymers, as a polar adhesive substance, can promote the adhesion between the asphalt layer and the metal foil of the base course. The side chain carboxyl groups of the acrylic polymer react with the polar groups on the surface of the metal foil, thereby further improving the adhesion between the base course and the modified asphalt layer.

[0012] Furthermore, the PET fiber is PET fiber filament obtained by blowing recycled PET film, PET textiles, or PET bottles; the length of the PET fiber filament is 3-25mm.

[0013] Furthermore, the tackifying resin includes one or more of C5 petroleum resin, C9 petroleum resin, terpene resin, rosin resin, and coumarone resin.

[0014] Furthermore, the polyethylene layer comprises the following raw materials in parts by weight: 80-130 parts by weight of high-density polyethylene, 30-55 parts by weight of metallocene-catalyzed polyethylene, 12-18 parts by weight of thermoplastic elastomer, 0.5-1 part by weight of initiator, 3-6 parts by weight of ceramsite, 5-11 parts by weight of sodium polyacrylate, and 2-3 parts by weight of root inhibitor.

[0015] By adopting the above technical solution, the polyethylene layer mainly serves as a waterproof functional layer to prevent groundwater from corroding the foundation. Sodium polyacrylate and ceramsite are compounded in the polyethylene layer. Sodium polyacrylate is a water-absorbing resin, and ceramsite also has strong water absorption. When the polyethylene layer cracks due to aging, the infiltrated water can be absorbed in time by the sodium polyacrylate and ceramsite dispersed in the polyethylene layer. After absorbing water, the two expand in volume, which can seal the cracks in time and inhibit water infiltration.

[0016] Furthermore, the base layer is made of copper foil or aluminum foil, and the thickness of the base layer is 0.04-0.1 mm.

[0017] Furthermore, the thickness of the modified asphalt layer is 3-8 mm, and the thickness of the polyethylene layer is 3-5 mm.

[0018] Secondly, this application provides a method for preparing the aforementioned polymeric polypropylene waterproof membrane, comprising the following steps:

[0019] S1. High-density polyethylene, metallocene-catalyzed polyethylene, thermoplastic elastomer, initiator, ceramsite, sodium polyacrylate and root inhibitor are melt-blended and extruded onto one surface of the base layer to form a polyethylene layer.

[0020] S2. Heat the asphalt base material to melt, control the temperature at 140-160℃, add SBS and acrylic copolymer, wait for SBS to swell, add tackifying resin, wait for it to dissolve, add the remaining raw materials, stir for 1-3 hours, and extrude and shape it on the other surface of the base course treated in step S1 to form a modified asphalt layer and obtain a pre-composite layer.

[0021] S3. The first polypropylene nonwoven fabric layer, the second polypropylene nonwoven fabric layer and the pre-composite layer obtained in step S2 are pressed and hot-pressed together by stretching rollers to obtain a polymer polypropylene waterproof membrane.

[0022] In summary, the present invention has at least one of the following beneficial technical effects:

[0023] 1. In this application, special additives, acrylic copolymers, inorganic fillers, and PET fibers are added to the modified bitumen layer of the polymer polypropylene waterproof membrane. These additives interact with the bitumen to form a uniform and stable network structure, resulting in a modified bitumen layer with strong impact resistance, high weather resistance, and strong adhesion to the metal substrate. Furthermore, the waterproofing performance of the polyethylene layer of the polymer polypropylene waterproof membrane is further improved by compounding sodium polyacrylate and ceramsite. The polymer polypropylene waterproof membrane produced in this application exhibits good waterproofing performance, impact resistance, mechanical properties, and puncture resistance.

[0024] 2. The polymer polypropylene waterproof membrane in this application has a simple preparation process, low raw material price, and is suitable for large-scale production and application. Detailed Implementation

[0025] The present application will be further described in detail below with reference to the embodiments.

[0026] This application designs a polymeric polypropylene waterproof membrane, which comprises, from top to bottom, a first polypropylene nonwoven fabric layer, a modified bitumen layer, a metal-based base layer, a polyethylene layer, and a second polypropylene nonwoven fabric layer. The modified bitumen layer comprises the following raw materials in parts by weight: 70-120 parts base bitumen, 4-6 parts tackifying resin, 6-10 parts SBS, 8-14 parts acrylic copolymer, 2-4 parts additives, 11-18 parts filler, 2-5 parts PET fiber, and 2-3 parts root inhibitor. The additives include pyromellitic dianhydride and triglycidyl isocyanate.

[0027] The polymer polypropylene waterproof membrane of this application is prepared by the following method, including the following steps:

[0028] S1. High-density polyethylene, metallocene-catalyzed polyethylene, thermoplastic elastomer, initiator, ceramsite, sodium polyacrylate and root inhibitor are melt-blended and extruded onto one surface of the base layer to form a polyethylene layer.

[0029] S2. Heat the asphalt base material to melt, control the temperature at 140-160℃, add SBS and acrylic copolymer, wait for SBS to swell, add tackifying resin, wait for it to dissolve, add the remaining raw materials, stir for 1-3 hours, and extrude and shape it on the other surface of the base course treated in step S1 to form a modified asphalt layer and obtain a pre-composite layer.

[0030] S3. The first polypropylene nonwoven fabric layer, the second polypropylene nonwoven fabric layer and the pre-composite layer obtained in step S2 are pressed and hot-pressed together by stretching rollers to obtain a polymer polypropylene waterproof membrane.

[0031] The technical problem solved by this application is that existing polypropylene composite waterproof membranes are usually composed of a polyethylene sheet in the middle and polypropylene nonwoven fabrics on both sides. The resulting waterproof membranes have low strength, poor weather resistance, and short service life. Furthermore, when used in underground waterproofing projects, they are easily punctured by stones in the concrete protective layer above, thus losing their intended waterproof performance. This application addresses this problem by adding special additives, acrylic copolymers, inorganic fillers, and PET fibers to the modified bitumen layer of the polymer polypropylene waterproof membrane. These additives interact with the bitumen to form a uniform and stable network structure, resulting in a modified bitumen layer with strong impact resistance, high weather resistance, and strong adhesion to the metal substrate. This application further improves the waterproof performance of the polyethylene layer by compounding sodium polyacrylate and ceramsite. The polymer polypropylene waterproof membrane produced in this application exhibits good waterproof performance, impact resistance, and mechanical properties, while also being resistant to stone scratches and root penetration.

[0032] Preparation Examples 1-5

[0033] Examples 1-5 show modified asphalt layers with different raw material ratios. The specific raw material ratios are shown in Table 1 (unit: parts by weight).

[0034]

[0035] Table 1

[0036] The base asphalt is a mixture of 90# and 200# petroleum asphalt in a weight ratio of 3:1. The 90# petroleum asphalt has a softening point of 40-60℃ and a penetration of 80-100 in 0.1mm, and is classified as medium-fuel 90# heavy-duty road petroleum asphalt; the 200# asphalt has a penetration of 180-220 in 0.1mm, and is classified as medium-fuel 200# petroleum asphalt.

[0037] Among them, SBS adopts Sinopec's SBS61401.

[0038] The acrylic copolymer is a hydroxyethyl acrylate-acrylic acid copolymer.

[0039] The additives are pyromellitic dianhydride and triglycidyl isocyanurate in a weight ratio of 1:1.

[0040] The filler is a mixture of talc powder and modified wollastonite in a weight ratio of 1:4, wherein the average particle size of the talc powder is 50 micrometers and the average particle size of the modified wollastonite is 2.5 mm.

[0041] The preparation of modified wollastonite includes the following steps:

[0042] A 10 wt% suspension of wollastonite was prepared in water, tung oil acid was added, the mixture was heated to 80°C, sonicated for 10 min, filtered, and the residue was washed and dried to obtain modified wollastonite. The weight ratio of wollastonite to tung oil acid was 10:1.

[0043] The average length of PET fibers is controlled at 20mm.

[0044] The tackifying resin used is C9 petroleum resin.

[0045] The root inhibitor uses copper oxide powder with an average particle size of approximately 5 micrometers.

[0046] Preparation Example 6

[0047] Preparation Example 6 is based on Preparation Example 2, except that talc powder is replaced with silica of the same particle size in Preparation Example 6.

[0048] Preparation Example 7

[0049] Preparation Example 7 is based on Preparation Example 2, except that: no modification treatment is performed on wollastonite in Preparation Example 7, and wollastonite of the same particle size is used.

[0050] Preparation Examples 8-9

[0051] Preparation Examples 8-9 show polyethylene layers with different raw material ratios.

[0052] The polyethylene layer in Example 8 comprises the following parts by weight of raw materials:

[0053] 120 parts high-density polyethylene, 35 parts metallocene-catalyzed polyethylene, 16 parts thermoplastic elastomer, 1 part initiator, 4 parts ceramsite, 8 parts sodium polyacrylate, and 2 parts root inhibitor.

[0054] The high-density polyethylene used is CNOOC Shell 5121B, with a melt flow index of 0.5 g / 10 min.

[0055] The metallocene-catalyzed polyethylene uses Exxon 2703HH, with a melt index of 2.0 g / 10 min.

[0056] The thermoplastic elastomer uses thermoplastic polyurethane elastomer (TPU), specifically Wanhua Chemical's WHT-1495EC type TPU.

[0057] The initiator used is dicumyl peroxide.

[0058] The root inhibitor uses copper oxide powder with an average particle size of approximately 5 micrometers.

[0059] Preparation Example 9 is based on Preparation Example 8, except that sodium polyacrylate is not added in Preparation Example 9.

[0060] Examples 1-8

[0061] Examples 1-8 are polymer polypropylene waterproof membranes made with different modified bitumen layers or polyethylene layers, the difference being the type of modified bitumen layer or polyethylene layer used. See Table 2 for details.

[0062] Table 2

[0063]

[0064] The base layer in Examples 1-8 uses copper foil with a thickness of approximately 0.08 mm.

[0065] In Examples 1-8, the thickness of the modified asphalt layer was controlled at 6 mm, the thickness of the polyethylene layer was controlled at 3.5 mm, and the thickness of the first polypropylene nonwoven fabric layer and the second polypropylene nonwoven fabric layer was controlled at 1.5 mm.

[0066] The preparation process of Examples 1-8 includes the following steps:

[0067] S1. High-density polyethylene, metallocene-catalyzed polyethylene, thermoplastic elastomer, initiator, ceramsite, sodium polyacrylate and root inhibitor are melt-blended at 160°C and extruded and shaped on one surface of the base layer to form a polyethylene layer.

[0068] S2. Heat the asphalt base material to melt, control the temperature at 150℃, add SBS and acrylic copolymer, wait for SBS to swell, add tackifying resin, wait for it to dissolve, add the remaining raw materials, stir for 1.5h, and extrude and shape it on the other surface of the base course treated in step S1 to form a modified asphalt layer, thus obtaining a pre-composite layer.

[0069] S3. The first polypropylene nonwoven fabric layer, the second polypropylene nonwoven fabric layer and the pre-composite layer obtained in step S2 are pressed and hot-pressed together by stretching rollers to obtain a polymer polypropylene waterproof membrane.

[0070] Comparative Example 1

[0071] Comparative Example 1 is based on Example 2, except that only pyromellitic dianhydride is added to the additives in the modified bitumen layer of the polymer polypropylene waterproof membrane in Comparative Example 1.

[0072] Comparative Example 2

[0073] Comparative Example 2 is based on Example 2, except that PET fibers are not added to the raw materials of the modified bitumen layer in the polymer polypropylene waterproof membrane of Comparative Example 2.

[0074] Performance testing

[0075] 1. The impact strength of the polymer polypropylene waterproof membranes prepared in Examples 1-8 and Comparative Examples 1-2 was determined with reference to standard GB / T1843-2008.

[0076] 2. The puncture strength of the polypropylene waterproof membranes prepared in Examples 1-8 and Comparative Examples 1-2 was determined with reference to standard GB / T3360.1-2014.

[0077] 3. The yield elongation and yield strength of the polypropylene waterproof membranes prepared in Examples 1-8 and Comparative Examples 1-2 were determined with reference to standard GB / T528-2009.

[0078] 4. Impermeability test: Referring to GB / T35467-2017 "Wet-laid waterproof membranes", the polymer polypropylene waterproof membranes prepared in Examples 1-8 and Comparative Examples 1-2 were first subjected to pre-aging treatment to simulate a waterproof membrane with a service life of 30 years. Then, in an environment with a water pressure of 0.3 MPa for 120 minutes, it was observed whether the aged polymer polypropylene waterproof membranes in Examples 1-8 and Comparative Examples 1-2 were permeable.

[0079] The measurement results are shown in Table 3.

[0080] Table 3

[0081]

[0082] Analysis of the data in Table 3 shows that the polymer waterproof membrane provided by this invention has excellent tensile deformation properties, puncture resistance, impact resistance, weather resistance, and good waterproof performance, making it suitable as a waterproof membrane for underground engineering. In this application, different additives are compounded in the modified bitumen layer of the polymer polypropylene waterproof membrane, and acrylic copolymers, inorganic fillers, and PET fibers are also added. These interact with the bitumen to form a uniform and stable network structure, resulting in a modified bitumen layer with strong impact resistance, high weather resistance, and strong adhesion to the metal substrate. Furthermore, the waterproof performance of the polyethylene layer of the polymer polypropylene waterproof membrane is further improved by compounding sodium polyacrylate and ceramsite. The polymer polypropylene waterproof membrane prepared in this application exhibits good waterproof performance, impact resistance, mechanical properties, and puncture resistance.

[0083] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A polymer polypropylene waterproof membrane, characterized in that, The polymer polypropylene waterproof membrane comprises, from top to bottom, a first polypropylene nonwoven fabric layer, a modified bitumen layer, a metal base layer, a polyethylene layer, and a second polypropylene nonwoven fabric layer. The modified asphalt layer comprises the following raw materials in parts by weight: 70-120 parts of base asphalt, 4-6 parts of tackifying resin, 6-10 parts of SBS, 8-14 parts of acrylic copolymer, 2-4 parts of additives, 11-18 parts of filler, 2-5 parts of PET fiber, and 2-3 parts of root inhibitor. The additives include pyromellitic dianhydride and triglycidyl isocyanurate. The polyethylene layer comprises the following raw materials in parts by weight: 80-130 parts by weight of high-density polyethylene, 30-55 parts by weight of metallocene-catalyzed polyethylene, 12-18 parts by weight of thermoplastic elastomer, 0.5-1 part by weight of initiator, 3-6 parts by weight of ceramsite, 5-11 parts by weight of sodium polyacrylate, and 2-3 parts by weight of root inhibitor.

2. The polymer polypropylene waterproof membrane according to claim 1, characterized in that, The filler comprises talc powder and modified wollastonite in a weight ratio of 1:3-6.

3. The polymer polypropylene waterproof membrane according to claim 2, characterized in that, The method for preparing the modified wollastonite includes the following steps: preparing a suspension of wollastonite in a solvent, adding tung oil acid, heating to 70-80℃, sonicating, filtering to collect the filter residue, washing, drying, and obtaining the modified wollastonite, wherein the weight ratio of wollastonite to tung oil acid is 10-15:

1.

4. The polymer polypropylene waterproof membrane according to claim 1, characterized in that, The acrylic copolymers include one or more of the following: methyl acrylate-acrylic copolymer, methyl methacrylate-acrylic copolymer, ethyl acrylate-acrylic copolymer, hydroxyethyl acrylate-acrylic copolymer, hydroxypropyl acrylate-acrylic copolymer, n-butyl acrylate-acrylic copolymer, isooctyl acrylate-acrylic copolymer, and glycidyl methacrylate-acrylic copolymer.

5. The polymer polypropylene waterproof membrane according to claim 1, characterized in that, The PET fiber is obtained by blowing recycled PET film, PET textiles, and PET bottles; the length of the PET fiber is 3-25mm.

6. The polymer polypropylene waterproof membrane according to claim 1, characterized in that, The tackifying resin includes one or more of C5 petroleum resin, C9 petroleum resin, terpene resin, rosin resin, and coumarone resin.

7. The polymer polypropylene waterproof membrane according to claim 1, characterized in that, The base layer is made of copper foil or aluminum foil, and the thickness of the base layer is 0.04-0.1 mm.

8. The polymer polypropylene waterproof membrane according to claim 1, characterized in that, The thickness of the modified asphalt layer is 3-8 mm, and the thickness of the polyethylene layer is 3-5 mm.

9. A method for preparing a polymeric polypropylene waterproof membrane according to any one of claims 1-8, characterized in that, Includes the following steps: S1. High-density polyethylene, metallocene-catalyzed polyethylene, thermoplastic elastomer, initiator, ceramsite, sodium polyacrylate and root inhibitor are melt-blended and extruded onto one surface of the base layer to form a polyethylene layer. S2. Heat the asphalt base material to melt, control the temperature at 140-160℃, add SBS and acrylic copolymer, wait for SBS to swell, add tackifying resin, wait for it to dissolve, add the remaining raw materials, stir for 1-3 hours, and extrude and shape it on the other surface of the base course treated in step S1 to form a modified asphalt layer and obtain a pre-composite layer. S3. The first polypropylene nonwoven fabric layer, the second polypropylene nonwoven fabric layer and the pre-composite layer obtained in step S2 are pressed and hot-pressed together by stretching rollers to obtain a polymer polypropylene waterproof membrane.

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