Modified palygorskite, method for preparing same, composition for asphalt waterproof coating, asphalt waterproof coating, method for preparing same, and application thereof

Abstract

The application relates to the technical field of building waterproofing, and discloses modified attapulgite, a preparation method of the modified attapulgite, a composition for asphalt waterproof coating, asphalt waterproof coating, a preparation method of the asphalt waterproof coating and application. The preparation method of the modified attapulgite comprises the following steps: mixing and treating a dispersion medium in which a modifier is dispersed and attapulgite at 90-110 DEG C to obtain the modified attapulgite; the modifier is selected from cerium stearate and / or lanthanum stearate; and the mass ratio of the attapulgite to the modifier is 1:0.03-0.2. The asphalt waterproof coating provided by the application can form a three-dimensional network structure through 'interface vulcanization', and can endow the product with higher shearing resistance and bonding strength, and can effectively resist the overall slippage of the waterproof layer.

Description

Technical Field

[0001] This invention relates to the field of building waterproofing technology, specifically to a modified attapulgite soil and its preparation method, a composition for asphalt waterproof coatings, asphalt waterproof coatings and their preparation methods and applications. Background Technology

[0002] In the construction industry, waterproofing is crucial to structural safety and lifespan. Early rigid waterproofing relied on the density of concrete, but as building scale increased and waterproofing requirements rose, concrete's defects became increasingly apparent. Its numerous internal pores and capillaries make it prone to cracking under the influence of temperature, settlement, and stress, thus facilitating water penetration.

[0003] Traditional waterproofing membranes and coatings are the mainstays of waterproofing in the construction industry. Waterproofing membranes rely on laying to form a physical barrier, while coatings rely on the density of the coating to provide waterproofing. However, the application of waterproofing membranes requires a high level of expertise from the substrate, and the joints are prone to leakage and aging and deformation, which significantly reduces their waterproofing performance. Coatings are widely used due to their excellent creep and self-healing capabilities. However, most current waterproofing coatings lack sufficient bonding strength and cohesive strength, making them prone to sagging on vertical surfaces or sloping roofs. Especially in high-temperature environments, they are unable to resist the slippage of the waterproofing layer caused by structural deformation.

[0004] Existing technologies typically increase viscosity by adding tackifying resins or increasing filler content, but this often comes at the cost of sacrificing the material's creep properties and workability. On the other hand, vulcanization crosslinking of polymers (SBS / SBR) is one of the reinforcement methods, but ordinary vulcanization systems are inefficient in complex organic media such as asphalt, resulting in uneven crosslinking networks.

[0005] Therefore, there is an urgent need for an innovative technical solution that can fundamentally and simultaneously improve the bonding strength and cohesive strength of non-curing coatings without sacrificing their core performance; thereby developing a new generation of high-viscosity, anti-slip, non-curing rubber asphalt waterproof coatings that combine excellent anti-sagging, anti-slip capabilities, and long-lasting reliability. Summary of the Invention

[0006] The purpose of this invention is to solve the problems of poor adhesion, poor anti-slip performance, and rapid performance degradation of existing asphalt waterproof coatings.

[0007] To achieve the above objectives, a first aspect of the present invention provides a method for preparing modified attapulgite, the method comprising:

[0008] The modified attapulgite is obtained by mixing the dispersion medium containing the modifier with attapulgite at 90-110℃.

[0009] The modifier is selected from cerium stearate and / or lanthanum stearate;

[0010] The mass ratio of the attapulgite clay to the modifier is 1:0.03-0.2.

[0011] A second aspect of the invention provides modified attapulgite prepared by the method described in the first aspect.

[0012] A third aspect of the present invention provides a composition for an asphalt waterproof coating, the composition comprising asphalt, a softener, a polymer elastomer, a vulcanizing agent, a tackifying resin, modified attapulgite, and an inorganic filler.

[0013] Based on the total mass of the composition, the content of the asphalt is 45-60 wt%, the content of the softener is 15-25 wt%, the content of the polymer elastomer is 8-12 wt%, the content of the vulcanizing agent is 0.1-0.4 wt%, the content of the tackifying resin is 3-6 wt%, the content of the modified attapulgite is 5-10 wt%, and the content of the inorganic filler is 8-15 wt%.

[0014] The modified attapulgite soil is the modified attapulgite soil described in the second aspect;

[0015] The polymer elastomer is a combination of styrene-butadiene rubber and styrene-butadiene-styrene block copolymer in a mass ratio of 1:1-3.

[0016] A fourth aspect of the present invention provides a method for preparing an asphalt waterproof coating, the method being carried out using the composition described in the third aspect, comprising:

[0017] (1) The asphalt, softener and tackifying resin are mixed in the first mixture to obtain the first material;

[0018] (2) The polymer elastomer is mixed with the first material in a second mixing process to obtain a second material;

[0019] (3) The modified attapulgite clay, inorganic filler and the second material are mixed in a third mixture to obtain the third material;

[0020] (4) The vulcanizing agent is mixed with the third material to obtain the asphalt waterproof coating.

[0021] The fifth aspect of the present invention provides an asphalt waterproof coating prepared by the method described in the fourth aspect.

[0022] The sixth aspect of the present invention provides the application of the bitumen waterproofing coating described in the fifth aspect in building waterproofing.

[0023] Compared with the prior art, the technical solution provided by the present invention has at least the following beneficial effects:

[0024] (1) The modified attapulgite provided by the present invention can be better dispersed in the asphalt matrix, avoiding agglomeration. More importantly, in the vulcanization stage of the preparation process, the rare earth accelerator builds a "molecular bridge" between the inorganic filler and the organic polymer, realizing true "interfacial vulcanization". This makes the attapulgite transform from a simple physical filler into an active chemical reinforcing point, greatly improving the cohesive strength of the coating.

[0025] (2) The asphalt waterproof coating provided by the present invention can form a very stable three-dimensional network structure (polymer-crosslinking point-filler) through "interface vulcanization", which gives the product extremely high shear resistance and bonding strength and can effectively resist the overall slippage of the waterproof layer.

[0026] (3) The modified attapulgite soil provided by the present invention can achieve a structural synergy effect with inorganic fillers, forming a more stable spatial support network.

[0027] (4) The asphalt waterproof coating provided by this invention is uniform and stable, with no risk of phase separation, and its performance does not degrade after long-term storage. Moreover, the rare earth ions provided by the modified attapulgite have a unique 4f electron layer structure, with strong coordination ability and variable valence state. They can capture alkyl free radicals generated during the thermal oxidation of rubber and have a strong coordination effect with these free radicals with lone pairs of electrons, effectively "capturing" or "passivating" these highly active free radicals, thereby terminating the chain reaction that leads to polymer chain breakage. The rare earth ions provided by the modified attapulgite can also catalytically decompose hydroperoxides during the aging process of rubber to generate relatively stable products (such as alcohols), while the rare earth ions themselves are not consumed in the reaction and play the role of catalyst.

[0028] (5) The asphalt waterproof coating provided by the present invention has high bonding strength and anti-slip properties, as well as high heat resistance and stronger durability. The formulation process is simplified and efficient, and the materials are more environmentally friendly. Detailed Implementation

[0029] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0030] As previously stated, a first aspect of the present invention provides a method for preparing modified attapulgite, the method comprising:

[0031] The modified attapulgite is obtained by mixing the dispersion medium containing the modifier with attapulgite at 90-110℃.

[0032] The modifier is selected from cerium stearate and / or lanthanum stearate;

[0033] The mass ratio of the attapulgite clay to the modifier is 1:0.03-0.2.

[0034] Preferably, the modifier is a combination of cerium stearate and lanthanum stearate in a mass ratio of 1:1.8-2.5. The inventors have discovered that, under this preferred embodiment, the high antioxidant and heat-resistant properties of cerium stearate and the high sulfurization activity and high crosslinking density of lanthanum stearate can be synergistically utilized, resulting in an asphalt waterproof coating with better durability and high adhesion and anti-slip properties.

[0035] Preferably, the mass ratio of the attapulgite clay to the modifier is 1:0.05-0.12. The inventors have found that insufficient modifier dosage results in low crosslinking density, poor mechanical properties, and poor durability and system phase stability, while excessive dosage leads to decreased creep performance and poor workability. Within this preferred range, a balance between durable and stable mechanical properties and workability can be achieved, resulting in an asphalt waterproof coating with better durable and stable high-viscosity anti-slip properties.

[0036] In a preferred embodiment, the dispersion medium is selected from at least one of aromatic oils, naphthenic oils, phthalic plasticizers, and liquid paraffin.

[0037] In some embodiments, the specific surface area of ​​the attapulgite soil is ≥120 m². 2 / g, oil absorption value ≥50g / 100g, cation exchange capacity ≥25mmol / 100g, whiteness ≥70.

[0038] In some embodiments, the amount of dispersion medium used is 1.5-2.5 g relative to each g of modifier.

[0039] Preferably, the attapulgite is preheated to 80-100°C before the mixing process.

[0040] It should be noted that, in this invention, the dispersion medium containing the modifier is in the form of a paste.

[0041] Preferably, the mixing process is carried out under stirring conditions, which include: a stirring speed of 1500-1800 rpm and a time of 20-40 min.

[0042] It should be noted that in this invention, the material obtained after the mixing process is a powder exhibiting extremely smooth and uniform flowability, similar to very dry sand or talc powder. It can be described as having "loose flowability" or a "flowing sand state" and can be directly used as a raw material for preparing asphalt waterproof coatings. Further details of this invention are omitted here, and those skilled in the art should not construe this as a limitation of the invention.

[0043] As previously stated, a second aspect of the present invention provides modified attapulgite prepared by the method described in the first aspect.

[0044] As mentioned above, a third aspect of the present invention provides a composition for asphalt waterproof coating, the composition comprising asphalt, a softener, a polymer elastomer, a vulcanizing agent, a tackifying resin, modified attapulgite, and an inorganic filler.

[0045] Based on the total mass of the composition, the content of the asphalt is 45-60 wt%, the content of the softener is 15-25 wt%, the content of the polymer elastomer is 8-12 wt%, the content of the vulcanizing agent is 0.1-0.4 wt%, the content of the tackifying resin is 3-6 wt%, the content of the modified attapulgite is 5-10 wt%, and the content of the inorganic filler is 8-15 wt%.

[0046] The modified attapulgite soil is the modified attapulgite soil described in the second aspect;

[0047] The polymer elastomer is a combination of styrene-butadiene rubber and styrene-butadiene-styrene block copolymer in a mass ratio of 1:1-3.

[0048] Preferably, the softener is selected from at least one of aromatic oils and naphthenic oils.

[0049] Preferably, the softener is an aromatic oil.

[0050] More preferably, the aromatic oil has a flash point ≥240℃, an aniline point of 35-50℃, an aromatic hydrocarbon content of 65-75wt%, and a kinematic viscosity of 80-120MPa•s at 40℃.

[0051] In a preferred embodiment, the asphalt described in this invention is selected from at least one of 70# asphalt, 90# asphalt, and 100# asphalt.

[0052] Preferably, the tackifying resin is selected from C5 resin and / or C9 resin.

[0053] Preferably, the vulcanizing agent is selected from at least one of sulfur, dicumyl peroxide, and zinc oxide.

[0054] More preferably, the vulcanizing agent is selected from sulfur.

[0055] Preferably, the inorganic filler is selected from at least one of talc powder, mica powder, and kaolin.

[0056] More preferably, the inorganic filler is talc; the average particle diameter of the talc is 10-15 μm.

[0057] As previously described, a fourth aspect of the present invention provides a method for preparing an asphalt waterproof coating, the method being carried out using the composition described in the third aspect, comprising:

[0058] (1) The asphalt, softener and tackifying resin are mixed in the first mixture to obtain the first material;

[0059] (2) The polymer elastomer is mixed with the first material in a second mixing process to obtain a second material;

[0060] (3) The modified attapulgite clay, inorganic filler and the second material are mixed in a third mixture to obtain the third material;

[0061] (4) The vulcanizing agent is mixed with the third material to obtain the asphalt waterproof coating.

[0062] Preferably, the conditions for the first mixing include: a temperature of 160-180°C and a time of 0.5-1h.

[0063] Preferably, the conditions for the second mixing include: a temperature of 170-185°C and a time of 1-3 hours.

[0064] In a preferred embodiment, the conditions for the third mixing include: a temperature of 170-185°C and a time of 0.5-2 hours.

[0065] Preferably, the conditions for the fourth mixing include: a temperature of 150-165°C and a time of 0.5-2 hours.

[0066] Preferably, the first mixture, the second mixture, the third mixture, and the fourth mixture are each carried out independently under stirring conditions, wherein the stirring speed of the first mixture is 800-1000 rpm, the stirring speed of the second mixture is 1000-1400 rpm, the stirring speed of the third mixture is 1000-1400 rpm, and the stirring speed of the fourth mixture is 600-800 rpm.

[0067] As previously stated, the fifth aspect of the present invention provides an asphalt waterproof coating prepared by the method described in the fourth aspect.

[0068] As previously stated, the sixth aspect of the present invention provides the application of the bitumen waterproofing coating described in the fifth aspect in building waterproofing.

[0069] The present invention will be described in detail below through examples.

[0070] Unless otherwise specified, all reagents and raw materials used in the following examples are commercially available products, and all reagents are analytical grade products; in the following examples, each wt% represents 100g.

[0071] raw material:

[0072] Cerium stearate: purchased from Kingsilan (Xiamen) New Materials Co., Ltd.;

[0073] Lanthanum stearate: purchased from Kingsilan (Xiamen) New Materials Co., Ltd.;

[0074] Attapulgite: grade: Palygel 500, purchased from Anhui Mingmei Mineral Chemical Co., Ltd.;

[0075] Asphalt: Grade 70 petroleum asphalt, purchased from China Petroleum & Chemical Corporation;

[0076] Styrene-butadiene rubber: Grade 095#, purchased from Shandong Gaoshi Science & Technology Co., Ltd.;

[0077] Styrene-butadiene-styrene block copolymer: grade YH-791, purchased from China Petroleum & Chemical Corporation;

[0078] Polymer elastomer: a combination of styrene-butadiene rubber and styrene-butadiene-styrene block copolymer in a mass ratio of 1:2.

[0079] Tackifying resin: C5 petroleum resin, purchased from Qingdao Zhenli Chemical Co., Ltd.;

[0080] Vulcanizing agent: sulfur;

[0081] Dispersion medium: aromatic oil;

[0082] Softener: Aromatic oil;

[0083] Talc powder: average particle diameter is 10μm; purchased from Liaoning Haicheng Talc Powder Company.

[0084] Preparation Example 1

[0085] Modifier: A combination of cerium stearate and lanthanum stearate in a mass ratio of 1:1.8;

[0086] The dispersion medium containing the modifier was mixed with attapulgite preheated to 90°C at 90°C (stirring speed 1600 rpm, time 30 min) to obtain the modified attapulgite Z1; the mass ratio of attapulgite to modifier was 1:0.05; the amount of aromatic oil was 1.5 g relative to each g of modifier.

[0087] Preparation Example 2

[0088] Modifier: A combination of cerium stearate and lanthanum stearate in a mass ratio of 1:2.5;

[0089] The dispersion medium containing the modifier was mixed with attapulgite preheated to 100°C at 110°C (stirring speed 1600 rpm, time 30 min) to obtain the modified attapulgite Z2; the mass ratio of attapulgite to modifier was 1:0.12; the amount of aromatic oil was 2.5 g relative to each g of modifier.

[0090] Preparation Example 3

[0091] This preparation example uses a similar process to Preparation Example 1. The difference is that in this preparation example, the amount of modifier is controlled in the same way as in Preparation Example 1, but the modifier is cerium stearate.

[0092] The rest are the same as in Preparation Example 1.

[0093] Modified attapulgite Z3 was prepared.

[0094] Preparation Example 4

[0095] This preparation example uses a similar process to Preparation Example 1. The difference is that in this preparation example, the amount of modifier is controlled in the same way as in Preparation Example 1, but the modifier is lanthanum stearate.

[0096] The rest are the same as in Preparation Example 1.

[0097] Modified attapulgite Z4 was prepared.

[0098] Preparation Example 5

[0099] This preparation example uses a similar process to Preparation Example 1. The difference is that in this preparation example, the amount of attapulgite is controlled to be the same as in Preparation Example 1, but the mass ratio of attapulgite to modifier is 1:0.2.

[0100] The rest are the same as in Preparation Example 1.

[0101] Modified attapulgite Z5 was prepared.

[0102] Preparation Example D1

[0103] This preparation example uses a similar process to Preparation Example 1, except that the mixing temperature in this preparation example is 70°C.

[0104] The rest are the same as in Preparation Example 1.

[0105] Modified attapulgite DZ1 was prepared.

[0106] Preparation Example D2

[0107] In this preparation example, a silane coupling agent was used to modify the surface of attapulgite. The specific operation steps are as follows:

[0108] Preprocessing:

[0109] The attapulgite clay (the same amount as in Example 1) was dried at 105°C for 3 hours to completely remove moisture, and the dried attapulgite clay was prepared for use.

[0110] A silane coupling agent (KH-550, γ-aminopropyltriethoxysilane) was prepared by mixing with anhydrous ethanol at a mass ratio of 1:10 to obtain a diluted solution. The amount of the silane coupling agent was 1.0 wt% of the mass of the attapulgite. Deionized water was added to initiate its hydrolysis. The mixture was stirred and mixed evenly to obtain the silane coupling agent diluted solution, which was then left to stand for later use.

[0111] Surface modification:

[0112] Add the dried attapulgite powder to a high-speed mixer and preheat it to 90°C;

[0113] The diluted silane coupling agent was slowly and evenly sprayed into the high-speed rotating attapulgite using a spraying device, and mixed at 1600 rpm for 30 minutes at 95°C.

[0114] After mixing, transfer the material to a tray and cure it in an oven at 120°C for 1 hour to allow the silane coupling agent to complete the bonding reaction with the attapulgite surface and completely remove ethanol and moisture.

[0115] Post-processing:

[0116] The solidified block material is lightly crushed using a pulverizer and then sieved.

[0117] Modified attapulgite DZ2 was prepared.

[0118] Preparation Example D3

[0119] This preparation example uses a similar process to Preparation Example 1. The difference is that in this preparation example, the material being modified is calcined kaolin, that is, an equal mass of calcined kaolin is used to replace the attapulgite in Preparation Example 1.

[0120] Modified calcined kaolin DZ3 was obtained.

[0121] Example 1

[0122] (1) The asphalt, softener and tackifying resin are mixed in the first mixture to obtain the first material; the conditions for the first mixing include: temperature of 160°C, time of 1h and stirring speed of 900rpm.

[0123] (2) The polymer elastomer is mixed with the first material to obtain the second material; the conditions for the second mixing include: temperature of 170°C, time of 1.5h, and stirring speed of 1200rpm.

[0124] (3) The modified attapulgite Z1, talc powder and the second material are mixed in a third mixture to obtain the third material; the conditions for the third mixing include: temperature of 170℃, time of 1h and stirring speed of 1200rpm.

[0125] (4) The vulcanizing agent and the third material are mixed in a fourth way to obtain the asphalt waterproof coating S1; the conditions for the fourth mixing include: temperature of 155°C, time of 1.5h, and stirring speed of 700rpm.

[0126] Based on the total mass of the raw materials used (asphalt waterproof coating composition), the amount of asphalt is 50 wt%, the content of the softener is 20 wt%, the content of the polymer elastomer is 8 wt%, the content of the vulcanizing agent is 0.1 wt%, the content of the tackifying resin is 3.9 wt%, the content of the modified attapulgite is 8 wt%, and the content of the talc is 10 wt%.

[0127] Example 2

[0128] (1) The asphalt, softener and tackifying resin are mixed in the first mixture to obtain the first material; the conditions for the first mixing include: temperature of 180°C, time of 0.5h and stirring speed of 900rpm.

[0129] (2) The polymer elastomer is mixed with the first material to obtain the second material; the conditions for the second mixing include: temperature of 175°C, time of 1.5h, and stirring speed of 1200rpm.

[0130] (3) The modified attapulgite Z2, talc powder and the second material are mixed in a third mixture to obtain the third material; the conditions for the third mixing include: temperature of 175℃, time of 1h and stirring speed of 1200rpm.

[0131] (4) The vulcanizing agent and the third material are mixed in a fourth way to obtain the asphalt waterproof coating S2; the conditions for the fourth mixing include: temperature of 160°C, time of 1.5h, and stirring speed of 700rpm.

[0132] Based on the total mass of the raw materials used (asphalt waterproof coating composition), the amount of asphalt is 55 wt%, the content of the softener is 15 wt%, the content of the polymer elastomer is 8 wt%, the content of the vulcanizing agent is 0.1 wt%, the content of the tackifying resin is 3.9 wt%, the content of the modified attapulgite is 10 wt%, and the content of the talc is 8 wt%.

[0133] Example 3

[0134] This embodiment follows a similar process to that of Example 1. The difference is that, in this embodiment, the modified attapulgite Z3 obtained from Preparation Example 3 of equal mass is used to replace the modified attapulgite Z1 in Example 1.

[0135] Everything else is the same as in Example 1.

[0136] Asphalt waterproof coating S3 was prepared.

[0137] Example 4

[0138] This embodiment follows a similar process to Example 1. The difference is that, in this embodiment, the modified attapulgite Z4 obtained from Preparation Example 4 of equal mass is used to replace the modified attapulgite Z1 in Example 1.

[0139] Everything else is the same as in Example 1.

[0140] Asphalt waterproof coating S4 was prepared.

[0141] Example 5

[0142] This embodiment follows a similar process to Example 1. The difference is that, in this embodiment, the modified attapulgite Z5 obtained from Preparation Example 5 of equal mass is used to replace the modified attapulgite Z1 in Example 1.

[0143] Everything else is the same as in Example 1.

[0144] Asphalt waterproof coating S5 was prepared.

[0145] Example 6

[0146] This embodiment follows a similar process to Embodiment 1, except that in this embodiment, mica powder of equal mass is used instead of talc powder in Embodiment 1.

[0147] Everything else is the same as in Example 1.

[0148] Asphalt waterproof coating S6 was prepared.

[0149] Comparative Example 1

[0150] This comparative example follows a similar procedure to Example 1, except that in this comparative example, modified attapulgite DZ1 obtained from Preparation Example D1 of equal mass is used instead of modified attapulgite Z1 in Example 1.

[0151] Everything else is the same as in Example 1.

[0152] The asphalt waterproof coating DS1 was prepared.

[0153] Comparative Example 2

[0154] This comparative example follows a similar procedure to Example 1, except that in this comparative example, modified attapulgite DZ2 obtained from preparation example D2 of equal mass is used instead of modified attapulgite Z1 in Example 1.

[0155] Everything else is the same as in Example 1.

[0156] The asphalt waterproof coating DS2 was prepared.

[0157] Comparative Example 3

[0158] This comparative example follows a similar procedure to Example 1, except that in this comparative example, modified attapulgite DZ3 obtained from Preparation Example D3 of equal mass is used instead of modified attapulgite Z1 in Example 1.

[0159] Everything else is the same as in Example 1.

[0160] The asphalt waterproof coating DS3 was prepared.

[0161] Comparative Example 4

[0162] This comparative example follows a similar process to Example 1. The difference is that the attapulgite used in this comparative example is not modified; that is, an equal mass of attapulgite is used to replace the modified attapulgite Z1 in Example 1.

[0163] Everything else is the same as in Example 1.

[0164] The asphalt waterproof coating DS4 was prepared.

[0165] Test case

[0166] The performance of the asphalt waterproof coatings obtained in the above embodiments and comparative examples was tested.

[0167] Test method for adhesion performance (standard): Test method "A" of Chapter 7, Adhesion Strength, in GB / T 16777-2008 "Test Methods for Waterproof Coatings for Buildings".

[0168] Shear resistance test method (standard): Custom shear peel test method, the steps are as follows:

[0169] 1. Specimen preparation

[0170] a. Materials and Equipment:

[0171] Substrate: Cement mortar board conforming to Appendix A of JC / T 547-2017 standard, with dimensions of 150mm (length) × 50mm (width) × 10mm (thickness). It must be cleaned and dried before use, with a smooth surface free of laitance.

[0172] SBS waterproof membrane: Type II 4.0mm (PY-PE) polyester-based SBS modified bitumen waterproof membrane conforming to GB18242-2008 standard, cut into sheets of 150mm (length) × 50mm (width).

[0173] The coating to be tested: the asphalt waterproof coating prepared in the examples or comparative examples.

[0174] Template: Metal thickness control template, with a rectangular hole in the middle measuring 100mm (length) × 25mm (width) × 2.0mm (thickness).

[0175] Scraper, compaction roller.

[0176] b. Preparation steps:

[0177] (1) Place the cement mortar board horizontally.

[0178] (2) Press the template firmly and flat in the center of the cement mortar board, ensuring that the long side of the rectangular hole of the template is parallel to the long side of the cement board, and the distance between the short side of the rectangular hole and the short side of the cement mortar board is ≤5mm.

[0179] (3) Fill the rectangular hole of the template with a sufficient amount of the coating to be tested, and smooth it with a scraper to ensure that the coating is fully filled and the thickness is uniform at 2.0 mm.

[0180] (4) Move the template vertically upward to obtain a rectangular coating layer with precise dimensions on the cement board. Heat melt the PE film on one end of the SBS roll material for a length of 100mm.

[0181] (5) Suppose the uncured end of the SBS roll material is flatly placed over the uncured coating, ensuring that one end of the roll material is aligned with the end of the coating closest to the inside of the cement board. Use a compaction roller (applying pressure of about 2 kg) to roll back and forth 3-5 times within the bonding area (100 mm × 25 mm) to remove air and ensure that the roll material and coating layer are fully bonded to form an effective "SBS roll material-coating-cement board" composite specimen. The other end of the roll material (50 mm in length) is a free end, at 180° to the other end of the cement board, and is not bonded to any material.

[0182] (6) The prepared composite specimens were left to stand for 24 hours under standard test conditions ((23±2)℃, relative humidity (50±10)%) for testing. At least 3 valid specimens were prepared for each group of samples.

[0183] 2. Test Procedure

[0184] a. Equipment: Universal tensile testing machine with an accuracy of not less than grade 1.

[0185] b. Clamping:

[0186] Securely fix one end of the cement mortar board of the composite specimen in the lower clamp of the testing machine.

[0187] The free end (the unbonded 50mm portion) of the SBS roll is clamped in the upper fixture of the testing machine.

[0188] Ensure that the line of action of the tensile force is parallel to the bonding plane and passes through the center of the bonding surface.

[0189] c. Loading:

[0190] Start the testing machine and apply a tensile load to the specimen at a constant speed of (100±10) mm / min.

[0191] Continue loading until the specimen completely fails (the SBS roll separates from the cement board).

[0192] d. Data Recording:

[0193] Record the maximum load value F (unit: Newton, N) displayed by the instrument during the test.

[0194] 3. Result Calculation

[0195] a. The maximum shear strength (τ) is calculated using the following formula:

[0196] τ=F / A

[0197] In the formula:

[0198] τ—Maximum shear strength, in megapascals (MPa);

[0199] F—Maximum load, in Newtons (N);

[0200] A—Bonded area, in square millimeters (mm²); in this standard method, A = 100mm × 25mm = 2500mm 2 .

[0201] b. The calculation results are expressed as the arithmetic mean of at least three specimens, accurate to 0.01 MPa.

[0202] Test method for anti-slip properties of composite with roll material: The sample is heated to melt and scraped onto a qualified concrete slab with a coating area of ​​(150×120) mm² and a thickness of (2±0.2) mm. The concrete slab size is 200 mm×150 mm×5 mm. After coating, it is cured under standard curing conditions for 2 h±5 min. A prepared 4 mm thick SBS bitumen-based waterproof roll material is hot-melted to remove the surface PE release film and then pasted onto the coating (roll material size 125 mm×100 mm). It is rolled back and forth three times with a 2 kg roller to ensure complete adhesion between the roll material and the sample. It is placed under standard conditions for 24 h. A horizontal line is drawn on the upper edge of the roll material, with both ends of the line extending beyond the coating width. The sample is placed vertically in an electric heating drying oven that has been kept at a constant temperature to the specified temperature, with the distance between the sample and the oven wall not less than 50 mm. After 2 h±2 min of treatment, the sample is removed and the vertical slip distance between the upper edge of the sample and the drawn line is observed and measured. A total of 3 specimens were tested;

[0203] Test method for heat resistance (standard): The test method for heat resistance refers to JC / T 2428-2017, and the test temperature is 90℃;

[0204] Test method for bond strength retention rate after heat aging (standard): Bond strength retention rate after heat aging: Tested according to GB / T16777-2008. First, test the initial bond strength according to the test method "A" of Chapter 7 Bond Strength, then treat another group of specimens in a 70℃ oven for 168 hours and measure their bond strength, and calculate the retention rate;

[0205] The test results are shown in Table 1.

[0206] Table 1

[0207]

[0208] As can be seen from the results in Table 1, the asphalt waterproof coating obtained by the present invention has superior shear peel strength, anti-slip properties, bond strength, heat resistance and heat aging properties.

[0209] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A composition for asphalt waterproof coating, characterized in that, The composition contains asphalt, softener, polymer elastomer, vulcanizing agent, tackifying resin, modified attapulgite, and inorganic filler; Based on the total mass of the composition, the content of the asphalt is 45-60 wt%, the content of the softener is 15-25 wt%, the content of the polymer elastomer is 8-12 wt%, the content of the vulcanizing agent is 0.1-0.4 wt%, the content of the tackifying resin is 3-6 wt%, the content of the modified attapulgite is 5-10 wt%, and the content of the inorganic filler is 8-15 wt%. The polymer elastomer is a combination of styrene-butadiene rubber and styrene-butadiene-styrene block copolymer in a mass ratio of 1:1-3; The modified attapulgite clay is prepared using a method comprising the following steps: The modified attapulgite is obtained by mixing the dispersion medium containing the modifier with attapulgite at 90-110℃. The modifier is selected from cerium stearate and / or lanthanum stearate; The mass ratio of the attapulgite clay to the modifier is 1:0.03-0.

2.

2. The composition according to claim 1, characterized in that, The modifier is a combination of cerium stearate and lanthanum stearate in a mass ratio of 1:1.8-2.5; And / or, the mass ratio of the attapulgite clay to the modifier is 1:0.05-0.12; And / or, the dispersion medium is selected from at least one of aromatic oils, naphthenic oils, phthalic plasticizers, and liquid paraffin.

3. The composition according to claim 2, characterized in that, The specific surface area of ​​the attapulgite soil is ≥120m². 2 / g, oil absorption value ≥50g / 100g, cation exchange capacity ≥25mmol / 100g, whiteness ≥70.

4. The composition according to claim 1, characterized in that, The softener is selected from at least one of aromatic oils and naphthenic oils; And / or, the tackifying resin is selected from C5 resin and / or C9 resin; And / or, the vulcanizing agent is selected from at least one of sulfur and dicumyl peroxide.

5. The composition according to claim 4, characterized in that, The softener is an aromatic oil.

6. A method for preparing asphalt waterproof coating, characterized in that, This method is performed using the composition according to any one of claims 1-5, comprising: (1) The asphalt, softener and tackifying resin are mixed in the first mixture to obtain the first material; (2) The polymer elastomer is mixed with the first material in a second mixing process to obtain a second material; (3) The modified attapulgite clay, inorganic filler and the second material are mixed in a third mixture to obtain the third material; (4) The vulcanizing agent is mixed with the third material to obtain the asphalt waterproof coating.

7. The method according to claim 6, characterized in that, The conditions for the first mixing include: a temperature of 160-180℃ and a time of 0.5-1h; And / or, the conditions for the second mixing include: a temperature of 170-185°C and a time of 1-3 hours; And / or, the conditions for the third mixing include: a temperature of 170-185°C and a time of 0.5-2 hours; And / or, the conditions for the fourth mixing include: a temperature of 155-165°C and a time of 0.5-2 hours.

8. The asphalt waterproof coating prepared by the method according to claim 6 or 7.

9. The application of the asphalt waterproof coating according to claim 8 in building waterproofing.

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