Processing technology of hot melt glue spraying type cement-based mortar composite cement blanket

Abstract

The invention relates to the technical field of constructional engineering material manufacturing, and discloses a processing technology of a hot-melt glue-spraying type cement-based mortar composite cement blanket, which comprises the following steps of: unwinding and aligning upper-layer geotechnical cloth and lower-layer geotechnical cloth, spreading modified cement-based mortar dry powder on the surface of the lower-layer geotechnical cloth, leveling and pre-compacting; covering upper-layer geotechnical cloth and performing composite needling to form a composite blanket; after the composite blanket is subjected to hot rolling treatment, phase separation type modified hot melt adhesive is spirally sprayed to one side of the lower-layer geotechnical cloth; then feeding into a heating channel for gradient temperature control annealing treatment, and inducing the gel layer to be separated to form a communicated pore channel; and finally, inorganic mineral powder is sprayed to the surface of the adhesive layer to carry out surface in-situ passivation treatment, and cooling, coiling and packaging are carried out. A gradient temperature control annealing process is matched with a phase separation type hot melt adhesive system, a microscopic communicated pore channel network penetrating through a hydrophobic matrix is constructed, powder leakage can be effectively blocked, and rapid hydration hardening of a core layer material is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of building materials manufacturing technology, specifically to a processing technology for a hot-melt spray adhesive type cement-based mortar composite cement blanket. Background Technology

[0002] Cement-based composite blankets, as a new type of building material combining flexibility and rigidity, play an important role in water conservancy channel seepage prevention, slope reinforcement, and emergency rescue projects. In its dry state, the material is in roll form, facilitating storage, transportation, and on-site cutting and laying. Upon contact with water, it undergoes a hydration reaction and hardens, forming a high-strength concrete slope protection layer. This construction method eliminates the complex on-site mixing, formwork, and curing processes required by traditional concrete pouring, significantly shortening the construction cycle. It is particularly suitable for engineering projects in remote areas or regions with complex terrain.

[0003] In existing technologies for manufacturing such composite materials, needle punching combined with surface coating or adhesive treatment is typically used to fix the internal powder and connect the upper and lower fabric layers. This process involves laminating a continuous hot melt adhesive film or coating layer onto the surface of the nonwoven fabric, utilizing the density of the polymer material to physically seal the internal powder. This structural design effectively withstands vibration and compression during long-distance transportation, significantly reducing the risk of fine particles leaking through fabric pores. This ensures that the material meets weight and appearance standards upon arrival at the construction site, satisfying the requirements for dry-state packaging and storage.

[0004] However, the aforementioned continuous closed structure presents a fundamental contradiction between sealing and permeability in practical applications. While the continuously distributed hydrophobic adhesive layer prevents powder leakage, it also cuts off the penetration path of external curing moisture into the core layer. This makes it difficult for moisture to quickly wet the internal cement powder during construction, often resulting in incomplete hydration or surface hardening with internal looseness. At the same time, conventional hot melt adhesive materials tend to exhibit pressure-sensitive adhesion under high-temperature stacking conditions, causing adhesion between the internal layers of the roll material. Forcibly unfolding it will damage the base fabric structure. Furthermore, the organic adhesive layer and the inorganic cement core layer rely solely on simple physical bonding. In long-term water immersion environments, due to differences in interfacial tension and the wedging effect of water molecules, interfacial delamination is highly likely to occur, affecting the overall durability of the structure. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a processing technology for hot-melt spray adhesive type cement-based mortar composite cement blankets. This technology aims to solve the technical defects of existing composite cement blankets, such as the difficulty in simultaneously ensuring the sealing performance of powder packaging in a dry state and the water penetration efficiency after contact with water, the insufficient interfacial bonding force between the organic adhesive layer and the inorganic cement core layer in a humid and hot environment, the tendency for the layers of the roll material to stick together during high-temperature storage, and the delayed surface wetting in the early stages of construction.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a processing method for a hot-melt spray adhesive type cement-based mortar composite cement blanket, comprising the following steps: S1. Unroll the upper geotextile and the lower geotextile separately and keep them aligned; S2. Spread the modified cement-based mortar dry powder evenly on the surface of the lower geotextile, and then level and pre-compact it. S3. The upper geotextile is covered on the powder layer and composite needle punching is performed to form a composite blanket. S4. The composite blanket is subjected to hot rolling treatment to lock the surface fibers; S5. After melting the phase-separation modified hot melt adhesive, spray it onto one side of the lower geotextile using a spiral spraying method; S6. The composite blanket after spraying adhesive is sent into a heating channel for gradient temperature-controlled annealing, and the heat energy is used to induce phase separation inside the adhesive layer to form interconnected channels. S7. Before the adhesive layer cools, spray inorganic mineral powder evenly onto the surface of the adhesive layer for in-situ passivation treatment. S8. After cooling, winding and packaging.

[0007] By adopting the above technical solution, this invention resolves the contradiction between sealing and permeability by utilizing the synergistic effect of gradient temperature-controlled annealing and in-situ surface passivation. First, the adhesive layer sprayed in step S5 forms a continuous physical covering layer in its initial state, capable of preventing internal powder leakage. Subsequently, during the gradient temperature-controlled annealing process in step S6, the adhesive layer is in a semi-molten state. Utilizing the polarity difference and thermodynamic incompatibility between polymer components, hydrophilic components are induced to migrate and aggregate directionally in the hydrophobic matrix, constructing a microscopic interconnected phase region that permeates the adhesive layer. When the product is used in contact with water, this hydrophilic phase region rapidly dissolves or swells, forming channels for water to enter the core layer, thereby maintaining dry-state sealing while achieving wet-state conductivity. The in-situ surface passivation treatment in step S7, by embedding inorganic mineral particles, eliminates residual adhesiveness on the adhesive layer surface to prevent roll adhesion, while simultaneously increasing the surface energy of the adhesive layer surface, allowing external moisture to overcome surface tension, spread rapidly, and penetrate through the pores, accelerating the hydration reaction.

[0008] Preferably, the phase-separated modified hot melt adhesive described in step S5 is made from raw materials comprising the following parts by weight: 50-60 parts of ethylene-vinyl acetate copolymer, 15-20 parts of hydrogenated petroleum resin, 20-25 parts of polyethylene glycol, 5-8 parts of polypropylene wax, and 1.0-2.0 parts of γ-methacryloyloxypropyltrimethoxysilane.

[0009] By adopting the above technical solution, this hot melt adhesive formulation constructs a ternary system consisting of a hydrophobic matrix, a hydrophilic porous dispersion phase, and an interface anchoring agent. Its mechanism of action is as follows: ethylene-vinyl acetate copolymer and hydrogenated petroleum resin form a continuous hydrophobic matrix, providing basic adhesive strength and flexibility, and preventing powder leakage; polyethylene glycol, as a hydrophilic porous component, is partially compatible with the matrix resin in the molten state, undergoes phase separation upon cooling, dissolves and is lost in subsequent water exposure, leaving interconnected microporous channels; γ-methacryloyloxypropyltrimethoxysilane, as an interface anchoring component, contains methoxy groups that hydrolyze to generate silanol groups under water conditions, which condense with the hydroxyl groups on the surface of the core layer cement hydration products to form chemical bonds. Simultaneously, its organic functional groups physically entangle with the molecular chains of the ethylene-vinyl acetate copolymer, thereby improving the wet-heat bonding strength between the adhesive layer and the cement paste interface and preventing long-term water immersion peeling.

[0010] Preferably, the preparation method of the phase-separated modified hot melt adhesive includes: first, melting and mixing the ethylene-vinyl acetate copolymer and the hydrogenated petroleum resin at 130-140°C; then heating to 155-165°C, adding the polypropylene wax and the polyethylene glycol, and shearing and stirring at 60-80 rpm for 20-30 minutes; then cooling to 145-150°C, adding the γ-methacryloyloxypropyltrimethoxysilane, and stirring at this temperature for 10-15 minutes, followed by granulation.

[0011] By employing the above technical solution, the stepwise shearing process ensures the formation of a micro-phase separation structure. Under the action of high temperature and high shear field, the melt viscosity decreases, and the hydrophilic polyethylene glycol is forcibly dispersed into micron-sized droplets, uniformly suspended in the hydrophobic matrix, forming a micron-sized dispersed phase structure. Furthermore, the subsequent addition of a silane coupling agent and control of the temperature below its reactive point achieves uniform coating of the coupling agent at the melt interface while avoiding the volatilization or pre-crosslinking failure of the coupling agent due to prolonged high temperature, ensuring its reactivity is retained in the final application.

[0012] Preferably, the phase-separated modified hot melt adhesive is made from the following raw materials in parts by weight: 52-55 parts of ethylene-vinyl acetate copolymer, 17-18 parts of hydrogenated petroleum resin, 22-23 parts of polyethylene glycol, 6.5-7 parts of polypropylene wax, and 1.2-1.5 parts of γ-methacryloyloxypropyltrimethoxysilane; wherein the polyethylene glycol has a weight-average molecular weight of 4000-6000.

[0013] By employing the above technical solution, the molecular weight of polyethylene glycol is controlled within the range of 4000-6000, thus balancing phase separation kinetics and dissolution rate. If the molecular weight is too low, the porogen tends to migrate to the surface during storage, leading to blooming; if the molecular weight is too high, migration resistance is high during annealing, making it difficult to form a connected network, and the dissolution rate in water is slow, delaying hydration time. This specific molecular weight range ensures that the porogen has suitable fluidity at the annealing temperature to complete polymerization and can be rapidly dissolved in water during use.

[0014] Preferably, in step S6, the process parameters for the gradient temperature-controlled annealing process are: the air temperature in the heating channel is maintained at 65-75°C, and the residence time of the composite blanket in the heating channel is 20-45 seconds.

[0015] By employing the above technical solution, the annealing temperature is set above the melting point of polyethylene glycol but below the flow point of the ethylene-vinyl acetate copolymer. Within this temperature range, the matrix resin maintains a semi-solid framework, preventing macroscopic flow of the adhesive layer and the resulting voids; while the dispersed polyethylene glycol is in a molten state, undergoing Brownian motion and fusing together under surface tension. A processing time of 20-45 seconds allows isolated droplets to connect into a network of interconnected channels, completing the morphological transformation from a physically sealed structure to a connected, permeable structure.

[0016] Preferably, in step S7, the inorganic mineral powder is hydrophilic modified fine silica sand or rapid-hardening sulfoaluminate cement dry powder; the particle size of the inorganic mineral powder is 200-300 mesh, and the powder application rate is 5-10 g / m³. 2 .

[0017] By employing the above technical solution, the 200-300 mesh particle size allows inorganic particles to partially embed into the adhesive layer surface without puncturing the adhesive film. This serves two purposes: firstly, it acts as a physical spacer, transforming the surface contact between the adhesive layer and the backing fabric into point contact, blocking the interdiffusion of polymer chain segments under pressure and preventing storage adhesion; secondly, it utilizes the high surface energy of silica sand or cement powder to construct hydrophilic points on the surface. When water droplets contact the surface, the hydrophilic particles disrupt the surface tension of the water, promoting water wetting along the particle interface and conduction to the internal polyethylene glycol channels, shortening the initial wetting time.

[0018] Preferably, in step S5, the specific process parameters for the spiral spraying are: melt temperature 160-170℃, hot air pressure 0.18-0.22MPa, spraying morphology as a spiral fiber, and coating amount of 35-45g / m². 2 .

[0019] By adopting the above technical solution, the spiral fiber-shaped spraying trajectory forms a multi-overlapping mesh coverage per unit area. Compared with traditional full coating or spot coating, this structure ensures overall sealing while providing more interconnected path nodes for subsequent phase separation and pore formation, and achieves effective powder barrier with a lower coating amount, thus reducing production costs.

[0020] Preferably, the modified cement-based mortar dry powder in step S2 is composed of the following components by mass percentage: 65.0% rapid-hardening sulfoaluminate cement, 31.0% 40-80 mesh quartz sand, 3.0% redispersible latex powder, 0.3% hydrophobic modified fumed silica, and 0.7% polycarboxylate superplasticizer and defoamer; the redispersible latex powder is a powder obtained by spray drying ethylene-vinyl acetate copolymer emulsion, with a glass transition temperature of -5℃±2℃.

[0021] By adopting the above technical solution, redispersible latex powder can be redispersed into a polymer emulsion upon contact with water. Its polymer segments interpenetrate between cement hydration products, forming an organic-inorganic interpenetrating network structure, which imparts flexibility and crack resistance to the hardened body. Simultaneously, the ethylene-vinyl acetate segments in the latex powder exhibit good thermodynamic compatibility with the hot melt adhesive matrix that permeates from the upper layer, enhancing the interfacial bonding between the core layer and the adhesive layer.

[0022] Preferably, in step S1, the upper geotextile is a polypropylene flat yarn woven geotextile, and the lower geotextile is a polyester filament needle-punched nonwoven geotextile; in step S3, the needle-punching density of the composite needle-punching is 45-55 needles / cm. 2 The needle penetration depth is 2.5-3.5mm, penetrating the underlying layer and exposing the needle tip.

[0023] By adopting the above technical solution, the needle punching parameters ensure that the upper and lower base fabrics are effectively connected by fiber bundles, fixing the intermediate powder layer within a three-dimensional mesh space. The needle punching depth is controlled between 2.5-3.5 mm, ensuring interlayer peel strength while avoiding the risk of powder leakage due to excessively deep needle punching causing excessively large pores in the lower base fabric.

[0024] Preferably, in step S4, the hot rolling process uses a heated light roller group, with the upper roller temperature set at 160-185℃, the lower roller temperature set at 205-215℃, the linear pressure at 3.0kN / m, and the contact time at 2-4 seconds.

[0025] By adopting the above technical solution and utilizing the high-temperature short-time contact process, the surfaces of the upper polypropylene flat yarn and the lower polyester filament rapidly undergo thermal shrinkage and slight melting and bonding, thereby closing the needle holes formed during the needle punching process, preventing fine powder from overflowing from the needle holes during transportation and vibration, and improving the overall sealing performance of the product.

[0026] This invention provides a processing technology for hot-melt spray adhesive-type cement-based mortar composite cement blanket. It has the following beneficial effects: 1. This invention employs a gradient temperature-controlled annealing process combined with a phase-separation hot melt adhesive system. Utilizing the thermodynamic incompatibility between polymer components, it induces the directional migration and aggregation of hydrophilic components in a semi-molten state, constructing a microscopic interconnected network of channels that penetrates the hydrophobic matrix. In a dry state, it maintains the physical integrity of the adhesive layer, effectively preventing powder leakage. In a water-contaminated environment, it can transform into a moisture transport channel, ensuring rapid hydration and hardening of the core material. Compared to existing technologies that rely solely on physical needle-punching or the use of fully enclosed hydrophobic adhesive films, this invention effectively solves the long-standing contradiction of composite cement blankets being prone to powder leakage during dry storage and difficult moisture penetration during the hydration period, significantly improving the engineering applicability of the material. 2. This invention introduces a silane coupling agent into the hot melt adhesive formulation and incorporates redispersible latex powder into the mortar core layer, constructing a dual enhancement mechanism of chemical bonding and interpenetrating network at the interface. The silanol groups generated by the hydrolysis of the silane coupling agent undergo a condensation reaction with the cement hydration products to form a chemical anchor. At the same time, the polymer network formed by the latex powder undergoes molecular chain entanglement with the adhesive matrix, which greatly improves the bonding force between the adhesive layer and the inorganic core layer in a humid and hot environment. Compared with the existing technology where hot melt adhesive and cement substrate are connected only by surface mechanical interlocking, this invention solves the problem of adhesive layer peeling and strength reduction caused by interface hydrolysis and swelling under long-term water immersion conditions, ensuring the durability of the composite structure. 3. This invention employs in-situ surface passivation technology, embedding inorganic mineral micropowders before the adhesive layer has completely cooled. The physical separation effect of the micropowders eliminates the pressure-sensitive adhesion of the adhesive layer surface, and the high surface energy of the mineral particles improves the surface wetting properties of the adhesive layer. This allows the roll material to maintain interlayer separation under high-temperature stacking and storage conditions, and to quickly break surface tension and introduce moisture during construction and watering. Compared with the shortcomings of existing EVA-based hot melt adhesives, such as the inability to unfold the roll material due to surface stickiness and the delay in initial hydration due to surface hydrophobicity, this invention significantly improves the storage stability and construction convenience of the product, and reduces the risk of material scrap. Attached Figure Description

[0027] Figure 1 This is a comparison chart of the dry powder leakage rate and 24-hour compressive strength of cement blankets under different process conditions in the test examples of this invention. Figure 2 This is a comparison diagram of the dry and wet interlayer peel strength of Example 1 and Comparative Example 3 of the test examples of the present invention; Figure 3 The test examples of this invention show the effect of surface passivation process on the storage stability and wettability of cement blankets; where (a) is a comparison diagram of anti-adhesion performance and (b) is a comparison diagram of surface wetting rate. Detailed Implementation

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] The main raw materials and reagents used in the following examples and comparative examples have the following sources and specifications. Reagents not specifically mentioned are all commercially available analytical grade or higher grade products.

[0030] Ethylene-vinyl acetate copolymer (EVA), CAS No. 24937-78-8, vinyl acetate (VA) content 28%, melt flow rate (MI) 400 g / 10 min (190℃, 2.16 kg).

[0031] Hydrogenated petroleum resin, CAS No. 64742-16-1, C9 fraction, softening point (ring and ball method) 100℃.

[0032] Polyethylene glycol (PEG-4000), CAS No. 25322-68-3, weight average molecular weight 4000; Polyethylene glycol (PEG-6000), weight average molecular weight 6000.

[0033] γ-Methacryloxypropyltrimethoxysilane (KH-570), CAS No. 2530-85-0, purity ≥98%.

[0034] Polypropylene wax, CAS No. 9003-07-0, dropping melting point 145℃.

[0035] Rapid-hardening sulfoaluminate cement, strength grade 42.5.

[0036] Redispersible latex powder (VAE), CAS No. 24937-78-8, is a powder obtained by spray drying of ethylene-vinyl acetate copolymer emulsion. It contains polyvinyl alcohol protective colloid and mineral anti-caking agent, with a bulk density of 400-600 g / L, ash content of 10%±2%, and glass transition temperature of -5℃±2℃.

[0037] Hydrophobically modified fumed silica, CAS No. 68611-44-9, surface-treated with dimethyldichlorosilane, with a specific surface area of ​​170 m² / g. 2 / g±20m 2 / g.

[0038] The upper geotextile is a polypropylene (PP) flat yarn woven geotextile, with raw material CAS number 9003-07-0 and a unit area mass of 125 g / m². 2 The warp and weft density is 12 threads / 10cm, and the breaking strength is ≥2.5kN / m.

[0039] The lower geotextile is a polyester (PET) filament needle-punched nonwoven geotextile, with raw material CAS number 25038-59-9 and a unit area mass of 250 g / m². 2 Fiber fineness 4D, porosity ≥80%.

[0040] Hydrophilic modified fine silica sand: a commercially available product, the main component of which is quartz, with a particle size of 200-300 mesh, and the surface is treated with hydrophilicity.

[0041] Preparation Example 1: This preparation example provides a method for preparing a phase-separated modified hot melt adhesive composition, comprising the following steps: (1) Weigh the following raw materials in parts by weight: 55 parts of ethylene-vinyl acetate copolymer (EVA), 18 parts of hydrogenated petroleum resin, 22 parts of polyethylene glycol (PEG-4000), 6.5 parts of polypropylene wax, and 1.5 parts of γ-methacryloyloxypropyltrimethoxysilane (KH-570). (2) Heat the reactor equipped with a heating jacket and anchor stirrer to 135°C, add the weighed ethylene-vinyl acetate copolymer and hydrogenated petroleum resin, start the stirrer and stir at 35 rpm until the resin is completely melted and transparent. (3) Raise the temperature of the reactor to 160°C, add polypropylene wax and polyethylene glycol (PEG-4000) in sequence, increase the stirring speed to 70 rpm, and shear stir at constant temperature for 25 minutes. Use high shear force to make the hydrophilic PEG uniformly dispersed in the form of micron-sized droplets in the hydrophobic EVA matrix, forming a micro-phase separation structure with uniform distribution of micron-sized dispersed phase. (4) Reduce the temperature of the reactor to 148°C and slowly add γ-methacryloxypropyltrimethoxysilane. After the addition is complete, continue to keep the temperature and stir for 12 minutes to ensure that KH-570 is uniformly coated and activated in situ at the melt interface, thus preventing local agglomeration. (5) Open the bottom valve of the reactor to discharge the material. After passing through the filter screen, the melt enters the water-cooled strip pelletizer for granulation. After air drying and screening, phase separation type modified hot melt adhesive particles are obtained and sealed for later use.

[0042] Preparation Example 2: This preparation example provides a method for preparing a phase-separated modified hot melt adhesive composition, comprising the following steps: (1) Weigh the following raw materials in parts by weight: 50 parts of ethylene-vinyl acetate copolymer (EVA), 15 parts of hydrogenated petroleum resin, 25 parts of polyethylene glycol (PEG-6000), 5 parts of polypropylene wax, and 2.0 parts of γ-methacryloyloxypropyltrimethoxysilane (KH-570). (2) Heat the reactor to 140°C, add ethylene-vinyl acetate copolymer and hydrogenated petroleum resin, and stir at 40 rpm until completely melted; (3) Heat to 165°C, add polypropylene wax and polyethylene glycol (PEG-6000), increase the speed to 80 rpm, and shear and stir at a constant temperature for 30 minutes to ensure the establishment of a stable phase separation precursor structure in the high viscosity melt; (4) Cool down to 150°C, add γ-methacryloyloxypropyltrimethoxysilane, and maintain stirring for 15 minutes to complete the uniform dispersion of KH-570; (5) Discharge the material and granulate it through a steel belt cooling granulator to obtain modified hot melt adhesive granules.

[0043] Preparation Example 3: This preparation example provides a method for preparing a phase-separated modified hot melt adhesive composition, comprising the following steps: (1) Weigh the following raw materials in parts by weight: 60 parts of ethylene-vinyl acetate copolymer (EVA), 20 parts of hydrogenated petroleum resin, 20 parts of polyethylene glycol (PEG-4000), 8 parts of polypropylene wax, and 1.0 part of γ-methacryloyloxypropyltrimethoxysilane (KH-570). (2) Heat the reactor to 130°C, add ethylene-vinyl acetate copolymer and hydrogenated petroleum resin, and stir at 30 rpm until completely melted; (3) Heat to 155℃, add polypropylene wax and polyethylene glycol (PEG-4000), increase the speed to 60 rpm, and shear and stir at a constant temperature for 20 minutes; (4) Cool down to 145°C, add γ-methacryloyloxypropyltrimethoxysilane, and maintain stirring for 10 minutes; (5) Discharge the material and granulate it through a water-cooled strip pelletizer to obtain modified hot melt adhesive granules.

[0044] Preparation Example 4: This preparation example provides a method for preparing a phase-separated modified hot melt adhesive composition, comprising the following steps: (1) Weigh the following raw materials in parts by weight: 52 parts of ethylene-vinyl acetate copolymer (EVA), 17 parts of hydrogenated petroleum resin, 23 parts of polyethylene glycol (PEG-4000), 7 parts of polypropylene wax, and 1.2 parts of γ-methacryloyloxypropyltrimethoxysilane (KH-570). (2) Heat the reactor to 135°C, add ethylene-vinyl acetate copolymer and hydrogenated petroleum resin, and stir until completely melted; (3) Heat to 160℃, add polypropylene wax and polyethylene glycol (PEG-4000), and shear and stir at 75 rpm for 25 minutes; (4) Cool down to 148°C, add γ-methacryloyloxypropyltrimethoxysilane, and stir for 12 minutes; (5) Discharge the material, granulate it, and obtain modified hot melt adhesive granules.

[0045] Example 1: This example provides a processing technology for hot-melt spray adhesive type cement-based mortar composite cement blanket, specifically including the following steps: (1) Constant tension unwinding: The upper layer of polypropylene flat yarn is woven into geotextile (unit area mass 125g / m). 2 ) and the underlying polyester filament needle-punched nonwoven geotextile (unit area mass 250g / m) 2 The two layers of base fabric are loaded onto a dual-station unwinding machine, with the unwinding tension set to 400N. The edge alignment of the two base fabrics is maintained by a correction controller. (2) Spreading and pre-compacting: The pre-mixed modified cement-based mortar dry powder is evenly spread on the surface of the lower layer of polyester filament needle-punched nonwoven geotextile using a slot spreader. The amount of material spread is controlled at 8000 g / m. 2 The modified cement-based mortar dry powder is composed of the following components by mass percentage: rapid-hardening sulfoaluminate cement 65.0%, 40-80 mesh quartz sand 31.0%, redispersible latex powder 3.0%, hydrophobic modified fumed silica 0.3%, and polycarboxylate superplasticizer and defoamer 0.7%. After spreading, it is leveled on a micro-vibration platform with a frequency of 50Hz and pre-compacted by a rubber roller with a linear pressure of 0.8kN / m. (3) Composite needle punching: The upper layer of polypropylene flat yarn woven geotextile is placed on top of the powder layer and fed into the needle punching unit. Composite needle punching is performed using barbed needles, and the needle punching density is set to 50 needles / cm. 2 The needle penetration depth is set to penetrate the bottom layer and expose the needle tip by 3.0mm; (4) Heat melt setting: The composite blanket is heated by a Teflon coating on the light roller group. The temperature of the upper roller (contacting the upper base fabric) is set to 180℃, and the temperature of the lower roller (contacting the lower base fabric) is set to 210℃. The linear pressure is 3.0kN / m and the contact time is 3 seconds, so that the surface fibers are thermally contracted to lock the pinholes. (5) Spiral hot melt spraying: The phase separation modified hot melt adhesive obtained in Preparation Example 1 was added to a hot melt adhesive machine for melting. The melt temperature was set to 165°C. The adhesive was then sprayed onto the non-woven side of the composite blanket in a spiral fiber form through a spiral nozzle under a hot air pressure of 0.2 MPa. The coating amount was 40 g / m. 2 ; (6) Gradient temperature control annealing: The composite blanket after spraying adhesive is immediately sent into a constant temperature heating channel for annealing. The air temperature in the channel is maintained at 70°C, and the composite blanket stays in the channel for 30 seconds to induce phase separation inside the adhesive layer. (7) In-situ passivation of the surface: Before the composite blanket leaves the annealing channel and before the adhesive layer cools down, immediately spray 200-mesh hydrophilic modified fine silica sand evenly onto the surface of the adhesive layer through an air-powder mixing nozzle. The amount of powder sprayed is 8g / m 2 ; (8) Post-processing: After double-line locking, the product is cooled to a surface temperature below 40°C by cooling rollers, then rolled up and sealed with PE heat shrink film.

[0046] Example 2: This example provides a processing technology for hot-melt spray adhesive type cement-based mortar composite cement blanket, specifically including the following steps: (1) Constant tension unwinding: The unwinding tension is set to 350N, and the substrate specifications are the same as in Example 1; (2) Spreading and pre-compacting: Use the same modified cement-based mortar dry powder with the same proportions as in Example 1, and control the amount of powder spread to 10000 g / m. 2 The vibration frequency was set to 45Hz, and the pressure roller linear pressure was set to 0.6kN / m. (3) Compound acupuncture: The acupuncture density is set at 45 needles / cm. 2 The needle insertion depth is set to 3.5mm; (4) Heat melt setting: The upper roller temperature is set to 175℃, the lower roller temperature is set to 205℃, and the contact time is set to 4 seconds; (5) Spiral hot melt spraying: The phase separation modified hot melt adhesive obtained in Preparation Example 2 was melted, the melt temperature was set to 160℃, the hot air pressure was set to 0.18MPa, and a spiral spraying method was used, with an adhesive application rate of 45g / m. 2 ; (6) Gradient temperature control annealing: The annealing channel temperature is set to 65°C and the dwell time is extended to 45 seconds to ensure that the polyethylene glycol components migrate and coalesce fully; (7) In-situ passivation of the surface: Spray dry powder of rapid-hardening sulfoaluminate cement with the same composition as the core layer evenly onto the surface of the adhesive layer, with a powder application rate of 10 g / m. 2 ; (8) Post-processing: After edge locking and cooling to room temperature, the product is rolled up and sealed for packaging.

[0047] Example 3: This example provides a processing technology for hot-melt spray adhesive type cement-based mortar composite cement blanket, specifically including the following steps: (1) Constant tension unwinding: The unwinding tension is set to 450N, and the substrate specifications are the same as in Example 1; (2) Spreading and pre-compacting: Use the same modified cement-based mortar dry powder with the same proportions as in Example 1, and control the amount of material spread to 6000 g / m. 2 The vibration frequency was set to 55Hz, and the pressure roller linear pressure was set to 1.0kN / m. (3) Compound acupuncture: The acupuncture density is set at 55 needles / cm. 2 The needle insertion depth is set to 2.5mm; (4) Heat melt setting: The upper roller temperature is set to 185℃, the lower roller temperature is set to 215℃, and the contact time is set to 2 seconds; (5) Spiral hot melt spraying: The phase separation modified hot melt adhesive obtained in Preparation Example 3 was melted, the melt temperature was set to 170°C, the hot air pressure was set to 0.22 MPa, and a spiral spraying method was used, with an adhesive application rate of 35 g / m. 2 ; (6) Gradient temperature control annealing: The annealing channel temperature is set to 75℃ and the dwell time is shortened to 20 seconds to accelerate the matrix crystallization and phase separation kinetics process by using higher temperature; (7) In-situ passivation of the surface: 300-mesh hydrophilic modified fine silica sand is evenly sprayed onto the surface of the adhesive layer, with a powdering amount of 5g / m 2 ; (8) Post-processing: After edge locking and cooling to room temperature, the product is rolled up and sealed for packaging.

[0048] Example 4: This example provides a processing technology for hot-melt spray adhesive type cement-based mortar composite cement blanket, specifically including the following steps: (1) Constant tension unwinding: The unwinding tension is set to 400N, and the substrate specifications are the same as in Example 1; (2) Spreading and pre-compacting: Use the same modified cement-based mortar dry powder with the same proportions as in Example 1, and control the spreading amount to 8000 g / m. 2 The micro-vibration leveling and compaction process parameters are the same as in Example 1; (3) Compound acupuncture: The acupuncture density is set at 50 needles / cm. 2 The needle insertion depth is set to 3.0 mm; (4) Heat melt setting: The upper roller temperature is set to 180℃, the lower roller temperature is set to 210℃, and the contact time is set to 3 seconds; (5) Spiral hot melt spraying: The phase separation modified hot melt adhesive obtained in Preparation Example 4 was melted, the melt temperature was set to 165℃, and a spiral spraying method was used, with an adhesive application amount of 38g / m. 2 ; (6) Gradient temperature control annealing: The annealing channel temperature is set to 72℃ and the dwell time is 25 seconds; (7) In-situ passivation of the surface: 200-mesh hydrophilic modified fine silica sand is evenly sprayed onto the surface of the adhesive layer, with a powdering amount of 6g / m 2 ; (8) Post-processing: After edge locking and cooling to room temperature, the product is rolled up and sealed for packaging.

[0049] Comparative Example 1: Compared with Example 1, the difference is that the gradient temperature-controlled annealing process in step (6) is omitted. That is, after the composite blanket is sprayed with adhesive in step (5), it does not enter the constant temperature heating channel, but directly enters step (7) for surface powdering and is immediately cooled to room temperature by cooling rollers. The remaining raw materials and process steps are the same.

[0050] Comparative Example 2: Compared with Example 1, the difference is that the surface passivation process in step (7) is omitted. That is, after the composite blanket undergoes the annealing treatment in step (6), it is not powdered and directly enters the post-processing process for cooling and winding. The remaining raw materials and process steps are the same.

[0051] Comparative Example 3: Compared with Example 1, the differences lie in the raw material formulation: 1. γ-methacryloyloxypropyltrimethoxysilane (KH-570) was not added to the hot melt adhesive composition used; this portion was made up by ethylene-vinyl acetate copolymer (EVA); 2. Redispersible latex powder (VAE) was not added to the modified cement-based mortar dry powder used; this portion was made up by quartz sand. All other process steps are the same as in Example 1.

[0052] Comparative Example 4: Compared to Example 1, the difference lies in the composition of the hot melt adhesive: the hot melt adhesive used is pure EVA hot melt adhesive, in which polyethylene glycol PEG, polypropylene wax, and KH-570 are all replaced by ethylene-vinyl acetate copolymer, and only the tackifying resin is retained. Since it does not contain PEG, the gradient temperature-controlled annealing process in step (6) is also omitted in this comparative example, and the coating is directly cooled after application. Everything else is the same.

[0053] Comparative Example 5: Compared with Example 1, the difference lies in the process parameters of step (6): the temperature of the annealing channel is set to 100°C, which is higher than the softening point of EVA and the melting point of PEG, while the rest are the same.

[0054] Test Example 1: Test objective: To evaluate the powder retention capacity of composite cement blankets prepared under different process conditions in a dry state and their hardening capacity after contact with water.

[0055] Experimental steps: (1) Sample preparation: From the finished products prepared in Examples 1 to 4 and Comparative Examples 1, 4 and 5, square samples with a size of 300mm×300mm were cut out respectively, and 5 parallel samples were prepared for each group.

[0056] (2) Dry vibration powder leakage rate test: The sample is laid flat and fixed on the screen of a standard vibrating screen machine with the adhesive surface facing down. The vibration frequency is set to 50Hz, the amplitude is 2mm, and the vibration is continued for 30 minutes. After the vibration is completed, all the powder that has fallen into the powder collection tray below is collected and weighed, and recorded as m1. The powder leakage rate L is calculated as (m1 / m2)×100%, where m2 is the theoretical total mass of powder calculated based on the amount of material.

[0057] (3) Wet hydration treatment: Immerse the sample after vibration test horizontally in a water tank, keep the water temperature at 20℃±2℃, and soak for 24 hours to ensure full reaction. Take out the sample and let the surface moisture drain naturally.

[0058] (4) Hardening performance test: The thickness of the sample was measured at 5 points (center and four corners) using vernier calipers. The average value was taken, and the loose surface layer due to lack of hydration was discarded. Only the thickness of the hardened layer that formed the strength was measured. Then, referring to the loading principle of the cement mortar strength test method, the hardened board was cut into standard test blocks of 40mm×40mm. A universal testing machine was used to load the blocks at a rate of 2400N / s±200N / s until failure. The maximum failure load was recorded and the compressive strength was calculated.

[0059] The experimental data are shown in Table 1: Table 1: Test data on sealing performance and hydration properties of each embodiment and comparative example

[0060] Note: The data in the table are the arithmetic mean of 5 parallel samples.

[0061] Conclusion: Based on Table 1 and Figure 1 Analysis of the test data showed a significant difference between Example 1 and Comparative Example 1, confirming the decisive role of gradient temperature-controlled annealing in constructing interconnected channels. Although Comparative Example 1 used the same polyethylene glycol (PEG) adhesive formulation as Example 1, the omission of the annealing step resulted in rapid cooling of the adhesive layer after melt spraying, causing the PEG dispersed phase to freeze into isolated microscopic regions. While this structure gave the material an extremely low powder leakage rate of 0.35% and exhibited good physical sealing, its 24-hour compressive strength was only 5.2 MPa, and the effective hardened thickness was less than 3 mm. This indicates that moisture could only penetrate very slowly through surface defects and could not truly penetrate the adhesive film to enter the core layer and trigger a hydration reaction. In contrast, Example 1, after annealing at 70°C, achieved a compressive strength of 41.3 MPa while maintaining a low powder leakage rate of 0.42%. This demonstrates that heat treatment in a semi-molten state successfully induced the migration and aggregation of the dispersed phase, transforming the originally isolated droplets into a interconnected network penetrating the adhesive layer, thereby forming effective moisture transport channels upon contact with water.

[0062] The test results of Comparative Example 4 further verified the necessity of the presence of polyethylene glycol. Although the use of pure ethylene-vinyl acetate copolymer hot melt adhesive achieved a minimum powder leakage rate of 0.08%, its compressive strength was 0 MPa, and it could not undergo hydration hardening at all. This confirms that the unmodified hydrophobic hot melt adhesive film completely blocks moisture transport, and the introduction of polyethylene glycol, combined with a specific process, is the material basis for achieving the functional conversion of the material to be sealed in a dry state and conductive in a wet state.

[0063] Furthermore, the data from Examples 2 and 3 show that both low-temperature long-time and high-temperature short-time annealing processes within a certain range can achieve excellent performance close to that of Example 1, indicating that the phase separation induction mechanism has a wide process adaptability window. However, the results of Comparative Example 5 show the boundary limitations of the process temperature; when the annealing temperature is increased to 100°C, the powder leakage rate surges to 8.94%. This is because the temperature exceeds the softening flow point of the matrix resin, causing macroscopic flow of the adhesive layer and generating large physical pores, which destroys the powder barrier structure of the material. In summary, this invention effectively solves the contradiction between sealing performance and water permeability in traditional hot melt adhesive sealing processes by performing annealing treatment within a specific temperature range, endowing the material with excellent wet hydration hardening ability while ensuring an extremely low powder leakage rate.

[0064] Test Example 2: Test objective: To investigate the interfacial bonding strength between the adhesive layer and the cement-based core layer of the composite cement blanket after standard hydration and hardening, and to conduct comparative tests under dry and wet conditions.

[0065] Experimental steps: (1) Sample preparation and curing: From the finished products prepared in Example 1 and Comparative Example 3, strip-shaped samples with dimensions of 50mm × 200mm were cut along the warp direction, and 10 parallel samples were prepared for each group. All samples were placed horizontally in a curing water tank, ensuring that the water level was 20mm above the sample surface, and were soaked and cured for 7 days at 20℃±1℃ to allow the core cement to fully hydrate and form a board with a certain strength. After curing, all samples were removed.

[0066] (2) Grouping: The 10 samples in each group were randomly divided into two groups of 5. The first group was used as the dry test group and dried in a 40℃ forced-air drying oven to constant weight. Then, it was conditioned for 24 hours in a standard laboratory environment (23℃, 50% humidity). The second group was used as the wet test group. After completing 7 days of curing, it was soaked in water for another 7 days. Before the test, it was taken out and the surface water was only absorbed with filter paper. The test was carried out immediately in a moist state.

[0067] (3) Peel strength test: Refer to GB / T 2790 "Test method for 180° peel strength of adhesives" and use a universal testing machine equipped with peel test fixtures for testing. A 50mm gap is pre-peeled at one end of the upper and lower base fabric layers of the sample to serve as the clamping area, and the sample is clamped in the upper and lower fixtures of the testing machine. A 180° peel is performed at a loading speed of 100mm / min, with a peel length of at least 100mm. The system automatically records the load curve during the peeling process, discards unstable data from the initial and final stages, and calculates the peel strength (N / 5cm) by dividing the average load of the intermediate stable section by the sample width (50mm).

[0068] The experimental data are shown in Table 2: Table 2: Interlayer peel strength test data of the examples and comparative examples

[0069] Note: The data in the table is the arithmetic mean of the test results of 5 parallel samples.

[0070] Conclusion: Based on Table 2 and Figure 2 Analysis of the test data showed that Example 1 and Comparative Example 3 exhibited fundamental differences in interlayer bonding performance, confirming the decisive role of the organic-inorganic chemical modification strategy in improving the wet heat durability of the material.

[0071] The dry peel strength of Comparative Example 3 was 28.4 N / 5 cm, while the wet peel strength plummeted to 5.7 N / 5 cm, with a strength retention rate of only 20.07%. In Comparative Example 3, due to the lack of γ-methacryloyloxypropyltrimethoxysilane and redispersible latex powder, only mechanical interlocking based on surface roughness and weak van der Waals forces existed between the hot melt adhesive layer and the cement hydration products. In the dry state, this physical anchoring could still provide a certain degree of bonding force; however, when the sample was in a water environment for a long time, water molecules penetrated to the interface between the adhesive layer and the cement paste through capillary action. Since the polarity of water is much greater than that of the ethylene-vinyl acetate copolymer matrix, water molecules rapidly replaced the physical adsorption sites between the adhesive layer and the substrate, forming a water film at the interface, leading to physical adhesion failure, which macroscopically manifested as a drastic decrease in wet peel strength.

[0072] In contrast, Example 1 not only achieved a higher strength of 46.8 N / 5 cm in the dry state, but more importantly, it maintained a peel strength of 41.2 N / 5 cm in the wet state, with a retention rate as high as 88.03%. This result verifies the aforementioned chemical reinforcement mechanism: First, the γ-methacryloyloxypropyltrimethoxysilane introduced in the formulation undergoes hydrolysis in the presence of moisture. The generated silanol groups undergo a condensation reaction with the hydroxyl groups on the surface of cement hydration products (such as calcium silicate hydrate), constructing a chemical bridge (Si-O-Si) at the interface between the organic adhesive layer and the inorganic core layer. At the same time, its organic end undergoes deep physical anchoring and molecular chain entanglement with the EVA matrix, effectively resisting interfacial hydrolysis. Second, the redispersible latex powder incorporated into the mortar migrates to the adhesive layer interface with moisture after dissolution. Its vinyl acetate segments undergo physical interdiffusion and entanglement with the same segments in the adhesive layer matrix, forming an interpenetrating network structure of organic polymer and inorganic cement stone during the cement hardening process. This dual mechanism of "chemical bonding + interpenetrating network" effectively resists interfacial hydrolysis and swelling stress, ensuring the integrity and reliability of the material structure under long-term water immersion conditions.

[0073] Test Example 3: Test objective: To investigate the anti-adhesion performance of composite cement blankets under simulated high-temperature storage conditions, as well as their surface hydrophilic wetting characteristics in the early stages of construction.

[0074] Experimental steps: (1) Sample preparation: From the finished products prepared in Example 1 and Comparative Example 2, square samples with a size of 100mm×100mm were cut out, and 10 samples were prepared for each group. Each group of samples was divided into two parts, with 5 samples used for anti-adhesion test and 5 samples used for wettability test.

[0075] (2) Simulated Warehouse Anti-Adhesion Test: The stacking and pressure method was used to simulate the internal stress of the roll material. Two samples from the same group were taken, and the adhesive surface of one sample was aligned with the back of the nonwoven fabric of the other sample. A standard weight was placed on top of the stacked samples, and a pressure of 5 kPa was applied. The whole sample was then placed in a constant temperature drying oven at 50°C for 24 hours. After the samples were removed and cooled to room temperature, the two layers of samples were manually separated to observe the ease of peeling and the surface condition of the adhesive layer. The anti-adhesion level was evaluated according to the following standards: Level 1 is natural separation or very slight adhesion, with no damage to the adhesive layer; Level 3 requires force to tear, with a small amount of adhesive layer fraying or tearing of the base fabric fibers; Level 5 is completely adhered and cannot be separated, and forced separation results in severe damage to the base fabric or large-area transfer of the adhesive layer.

[0076] (3) Surface wetting rate test: Fix the sample horizontally with the adhesive layer facing upward. Use a precision pipette to draw 0.1 mL of deionized water and drop it vertically to the center of the sample surface at a height of 10 mm. Use a high-definition camera to record the entire process from the water droplet contacting the surface to its complete spread and disappearance, and record the time required for the water droplet to disappear. If the water droplet has not completely penetrated after more than 180 seconds, it is recorded as ">180s".

[0077] The experimental data are shown in Table 3: Table 3: Test results of roll-up anti-adhesion and surface wetting rate of each group of samples

[0078] Conclusion: Based on Table 3 and Figure 3 Analysis of the test data showed that Example 1 and Comparative Example 2 exhibited distinctly different characteristics in terms of storage stability and surface hydrophilicity, strongly demonstrating the necessity of in-situ surface passivation in engineering applications.

[0079] In the anti-adhesion test, the samples of Comparative Example 2 were generally rated as level 4 to 5, exhibiting severe interlayer adhesion. This is because the hot melt adhesive matrix contains tackifying resin and precipitated low molecular weight polyethylene glycol. These components are in a viscous or highly elastic state at 50°C, exhibiting extremely strong pressure-sensitive adhesion. When the adhesive layer is directly in contact with the backing fabric under pressure, the flowing adhesive wets the fabric fibers, forming a physical lock upon cooling. In practical engineering, this adhesion can prevent the entire roll of cement blanket from being unfolded and laid, resulting in material scrap. In contrast, all samples of Example 1 were rated as level 1, with no resistance and no damage during the peeling process. This is attributed to the fact that the hydrophilic modified micro-silica sand sprayed in step 7 partially embedded in the adhesive layer surface, acting as a physical separator, transforming the surface contact between the adhesive layer and the fabric into a point contact supported by mineral particles, thereby completely blocking the mutual diffusion and adhesion of polymer chain segments.

[0080] Regarding surface wetting rate, the average wetting time of Comparative Example 2 exceeded 160 seconds, with some samples even exceeding 180 seconds without penetration. This indicates that the unpassivated adhesive layer surface is dominated by ethylene-vinyl acetate copolymer, exhibiting significant hydrophobicity, making it difficult for external moisture to overcome surface tension and enter the internal channels, thus delaying the initiation of the hydration reaction. In contrast, the average wetting time of Example 1 was only 3.3 seconds. The surface mineral micropowder not only eliminated stickiness but also constructed a high-surface-energy hydrophilic interface. When water droplets contact the surface, the hydrophilic powder rapidly disrupts the surface tension of water, guiding the moisture to spread along the powder interface within seconds and be introduced into the internal polyethylene glycol interconnected phase region. This water-attracting effect ensures that the cement blanket can immediately initiate the water absorption process after watering during construction, avoiding water loss and uneven hydration caused by surface hydrophobicity.

[0081] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A processing technology for a hot-melt spray adhesive type cement-based mortar composite cement blanket, characterized in that, Includes the following steps: S1. Unroll the upper geotextile and the lower geotextile separately and keep them aligned; S2. Spread the modified cement-based mortar dry powder evenly on the surface of the lower geotextile, and then level and pre-compact it. S3. The upper geotextile is covered on the powder layer and composite needle punching is performed to form a composite blanket. S4. The composite blanket is subjected to hot rolling treatment to lock the surface fibers; S5. After melting the phase-separation modified hot melt adhesive, spray it onto one side of the lower geotextile using a spiral spraying method; S6. The composite blanket after spraying adhesive is sent into a heating channel for gradient temperature-controlled annealing, and the heat energy is used to induce phase separation inside the adhesive layer to form interconnected channels. S7. Before the adhesive layer cools, spray inorganic mineral powder evenly onto the surface of the adhesive layer for in-situ passivation treatment. S8. After cooling, winding and packaging.

2. The processing technology of the hot-melt spray adhesive type cement-based mortar composite cement blanket according to claim 1, characterized in that, The phase-separated modified hot melt adhesive described in step S5 is made from raw materials comprising the following parts by weight: 50-60 parts of ethylene-vinyl acetate copolymer, 15-20 parts of hydrogenated petroleum resin, 20-25 parts of polyethylene glycol, 5-8 parts of polypropylene wax, and 1.0-2.0 parts of γ-methacryloyloxypropyltrimethoxysilane.

3. The processing technology of the hot-melt spray adhesive type cement-based mortar composite cement blanket according to claim 2, characterized in that, The preparation method of the phase-separated modified hot melt adhesive includes: first, melting and mixing the ethylene-vinyl acetate copolymer and the hydrogenated petroleum resin at 130-140°C; then heating to 155-165°C, adding the polypropylene wax and the polyethylene glycol, and shearing and stirring at 60-80 rpm for 20-30 minutes; then cooling to 145-150°C, adding the γ-methacryloyloxypropyltrimethoxysilane, and stirring at this temperature for 10-15 minutes, followed by granulation.

4. The processing technology of the hot-melt spray adhesive type cement-based mortar composite cement blanket according to claim 2, characterized in that, The phase-separated modified hot melt adhesive is made from the following raw materials in parts by weight: 52-55 parts of ethylene-vinyl acetate copolymer, 17-18 parts of hydrogenated petroleum resin, 22-23 parts of polyethylene glycol, 6.5-7 parts of polypropylene wax, and 1.2-1.5 parts of γ-methacryloyloxypropyltrimethoxysilane; the polyethylene glycol has a weight-average molecular weight of 4000-6000.

5. The processing technology of the hot-melt spray adhesive type cement-based mortar composite cement blanket according to claim 1, characterized in that, In step S6, the process parameters for the gradient temperature-controlled annealing process are as follows: the air temperature in the heating channel is maintained at 65-75℃, and the residence time of the composite blanket in the heating channel is 20-45 seconds.

6. The processing technology of the hot-melt spray adhesive type cement-based mortar composite cement blanket according to claim 1, characterized in that, In step S7, the inorganic mineral powder is hydrophilic modified fine silica sand or rapid-hardening sulfoaluminate cement dry powder; the particle size of the inorganic mineral powder is 200-300 mesh, and the powdering amount is 5-10 g / m³. 2 .

7. The processing technology of the hot-melt spray adhesive type cement-based mortar composite cement blanket according to claim 1, characterized in that, In step S5, the specific process parameters for the spiral spraying are: melt temperature 160-170℃, hot air pressure 0.18-0.22MPa, spraying morphology as a spiral fiber, and coating amount of 35-45g / m². 2 .

8. The processing technology of the hot-melt spray adhesive type cement-based mortar composite cement blanket according to claim 1, characterized in that, The modified cement-based mortar dry powder in step S2 is composed of the following components by mass percentage: 65.0% rapid-hardening sulfoaluminate cement, 31.0% 40-80 mesh quartz sand, 3.0% redispersible latex powder, 0.3% hydrophobic modified fumed silica, and 0.7% polycarboxylate superplasticizer and defoamer; the redispersible latex powder is a powder obtained by spray drying of ethylene-vinyl acetate copolymer emulsion, with a glass transition temperature of -5℃±2℃.

9. The processing technology of the hot-melt spray adhesive type cement-based mortar composite cement blanket according to claim 1, characterized in that, In step S1, the upper geotextile is a polypropylene flat yarn woven geotextile, and the lower geotextile is a polyester filament needle-punched nonwoven geotextile; in step S3, the needle-punching density of the composite needle-punching is 45-55 needles / cm. 2 The needle penetration depth is 2.5-3.5mm, penetrating the underlying layer and exposing the needle tip.

10. The processing technology of the hot-melt spray adhesive type cement-based mortar composite cement blanket according to claim 1, characterized in that, In step S4, the hot rolling process uses a heated light roller group, with the upper roller temperature set at 160-185℃, the lower roller temperature set at 205-215℃, the linear pressure at 3.0kN / m, and the contact time at 2-4 seconds.

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