Melt direct spinning polyester spun-bonded composite material as well as preparation method and application thereof

Abstract

The invention belongs to the field of industrial textiles, and relates to a melt direct spinning polyester spun-bonded composite material as well as a preparation method and application thereof. The melt direct spinning polyester spun-bonded composite material is prepared by the following steps: inputting a high-melting-point polyester melt formed by polycondensation of purified terephthalic acid and ethylene glycol and a low-melting-point PET melt formed by introducing isophthalic acid into a polycondensation system of phthalic acid and ethylene glycol into two spun-bonded heads through two sets of pipelines and metering pumps; the melt direct spinning polyester spun-bonded composite non-woven material for the flood prevention and embankment consolidation bag is formed through melt trickle cooling drafting and yarn separation, then an upper layer fiber web and a lower layer fiber web are laid, the middle is unrolled and fed into a high-strength glass fiber web to form a sandwich structure, and then the melt direct spinning polyester spun-bonded composite non-woven material for the flood prevention and embankment consolidation bag is formed after needling web fixation, hot air shrinkage, surface lustring and cooling. According to the melt direct spinning polyester spun-bonded composite material, the mechanical property of the melt direct spinning polyester spun-bonded composite material is improved through the high-strength glass fiber net, flexibility and sealing performance are provided through the PET spun-bonded non-woven material, and the storage space of flood prevention embankment fixing bags is saved.

Description

Technical Field

[0001] The invention belongs to the field of industrial textiles or nonwoven materials, and relates to a melt-spun polyester spunbond composite material and a preparation method and application thereof. Background Art

[0002] Flood control and embankment reinforcement materials refer to various substances specifically used to resist floods and reinforce river embankments. The selection and rational application of these materials directly affect the effectiveness and durability of flood control projects, and play a vital role in protecting people’s lives and property.

[0003] The development of flood control and embankment reinforcement materials reflects the determination of mankind to fight against natural disasters and the pace of technological progress. From early natural materials to modern high-tech products, they all play an important role in flood control and embankment reinforcement projects, especially flood control materials for emergency rescue projects. Early flood control and embankment reinforcement materials mainly relied on natural resources such as sandbags, wood and stone. These materials were effective in flood control and emergency rescue projects, but they were large in size and heavy in weight, which was not conducive to storage and transportation.

[0004] Geosynthetics are an important type of material that plays a key role in flood control and embankment reinforcement projects. With their unique advantages and diverse functions, these materials have made significant contributions to improving project efficiency, reducing costs and protecting the environment. With the rise of geosynthetics, geotextiles have begun to be widely used. These materials have good water permeability and filtration properties, which can effectively prevent the migration of soil particles while allowing water to pass freely. This feature makes them perform well in the construction of filter layers and drainage layers. However, these materials require infrastructure construction in advance, and cannot respond to sudden flood control and emergency rescue in a timely manner.

[0005] Spunbond nonwoven technology has the advantages of simple production process and high production efficiency, and the product has good mechanical properties. The vertical permeability coefficient of the material after needle punching is high. It is very mature in the application of geotextiles. If innovative design is carried out on this basis to develop a new type of flood control and embankment consolidation material that integrates geotextile and sandbag flood control materials, it will be of great significance to flood control and rescue, and to saving people’s lives and property. Summary of the invention

[0006] In view of the deficiencies of the prior art, the present invention provides a melt-spun polyester spunbond composite material for flood control and embankment consolidation, and a preparation method and application thereof. The polyester spunbond composite material for flood control and embankment consolidation prepared by the method of the present invention adopts a double S spunbond device, two S heads use PET melts with different melting points to perform one-step spinning into a web, a high-strength glass fiber net is added in the middle to reinforce the sandwich structure, and then the three-layer fiber net is needle-punched and compounded to form a polyester spunbond composite material for flood control and embankment consolidation bags. When used, the low-melting-point PET layer is used as the inner layer, the two layers of composite materials are made into a bag shape, bentonite is added in the middle and then hot-melt sealed to form a flood control and embankment consolidation bag. The preparation method has a simple production process and high production efficiency. The use of low-melting-point PET hot-melt sealing can simplify the sealing process and reduce the energy consumption of heat sealing. Its porous structure can also allow water to enter the bag, so that the bentonite expands by 20 to 30 times in volume after encountering water, which plays a role in flood control and embankment consolidation, and can save the storage space of the flood control and embankment consolidation bag. Among them, the high-strength glass fiber net improves its mechanical properties, and the PET spunbond nonwoven material provides flexibility and sealing, which is cost-effective.

[0007] The technical solution provided by the present invention is as follows:

[0008] A melt-spun polyester spunbond composite material, the material comprises two layers of melt-spun PET spunbond fiber webs and a layer of glass fiber web, the melt-spun PET spunbond fiber web comprises an upper and a lower layer, the lower layer is a high-melting-point PET spunbond fiber web, the upper layer is a low-melting-point PET spunbond fiber web, and the middle layer is a glass fiber web.

[0009] Furthermore, the high-melting-point PET spunbond web is formed by esterifying purified terephthalic acid and ethylene glycol to generate ethylene terephthalate, and then polycondensing to obtain a high-melting-point PET melt, which is then spun into a web, and the melt melting point is 250~260°C; the low-melting-point PET spunbond web is formed by introducing isophthalic acid into the polymerization system of purified terephthalic acid and ethylene glycol to obtain a low-melting-point PET melt, which is then spun into a web, and the melt melting point is 110~150°C.

[0010] Furthermore, the melt-spun polyester spunbond composite material has a mass per unit area of ​​90 to 140 g / m 2 The upper layer of low melting point PET spunbond fiber has a unit area mass of 30~50g / m 2 The mass per unit area of ​​the middle layer of glass fiber mesh is 20~30g / m 2 The unit area mass of the lower layer high melting point PET spunbond web is 40~60g / m 2 .

[0011] Furthermore, the melt-spun polyester spunbond composite material has a thickness of 0.40-0.60 mm, a longitudinal tensile strength of 300-500 N / 5 cm, an elongation of 30-40%, a transverse tensile strength of 200-350 N / 5 cm, and an elongation of 35-45%, and an air permeability of 1200-1500 mm / s.

[0012] The present invention also provides a preparation method for the above-mentioned melt-spun polyester spunbond composite material, which comprises: using a double S-head spunbond device, introducing a high-melting-point PET melt into the material path system of the lower spunbond head, and then forming a lower fiber web on the mesh curtain after metering by a metering pump, spinning by a spinning assembly, cooling and forming, airflow drawing, and filament separation; unwinding the glass fiber web and laying it on the high-melting-point PET spunbond fiber web layer to form a second fiber web; introducing a low-melting-point PET melt into the material path system of the upper spunbond head, and then metering by a metering pump, spinning by a spinning assembly, cooling and forming, airflow drawing, and filament separation, and then laying it on the glass fiber web to form an upper fiber web; the three-layer composite fiber web is sent to a needle punching machine for needle punching and fixing, and then hot air setting and smooth roller calendering are performed to obtain a melt-spun polyester spunbond composite material.

[0013] Furthermore, the preparation steps of the melt-spun PET spunbond fiber web layer include: conveying the low-melting-point PET melt and the high-melting-point PET melt to a melt filter respectively, and then conveying them to a metering pump with a rotation speed of 10-80 r / min for metering, and then conveying them to a spinning assembly, extruding the low-melting-point PET melt from a spinneret hole at 140-175° C., and extruding the high-melting-point PET melt from a spinneret hole at 275-290° C., and at 15-20° C., 4-6 kPa, and 60-96 m / min. The fibers are cooled and formed under the action of side blowing, and then air flow drawing is carried out. The drawing wind pressure is controlled to be 0.4~0.8MPa, the wind speed is 6000~10000m / min, and the wind temperature is 30~40℃. After air flow drawing, the fibers hit the inclined swing-blade type wire separation device for separation. The vibration frequency of the swing blade is 800~1000 times / min, and the amplitude is 3~4mm. After hitting the swing blade, the fibers scatter and form a melt-spun PET spunbond fiber web layer on the mesh curtain with the assistance of the suction device under the mesh.

[0014] Furthermore, the needle punching and web fixing step is: sending the sandwich structure web of the upper and lower layers of spunbond web and the glass fiber web in the middle into the needle punching area for needle punching and web fixing, and the needle punching density is 300-500 thorns / cm 2 .

[0015] Furthermore, the steps of hot air setting and smooth roller calendering include: sending the composite fiber web after needle punching into the hot air setting area, hot air setting at 120~150℃, and then sending it into the three-roller hot rolling area for surface ironing, wherein the middle roller is a cotton roller, and the upper and lower rollers are smooth rollers, and the temperatures are set to 110~130℃ and 180~220℃ respectively; after cooling, trimming and winding to obtain a melt-spun polyester spunbond composite material.

[0016] Furthermore, the upper and lower two layers of low-melting-point and high-melting-point PET melt-spun spunbond layers are unwound in the middle and added into a glass fiber mesh layer, and finally needle-punched to form a three-dimensional mesh structure.

[0017] Furthermore, the steps of spinning the lower fiber web into a web are as follows: the high melting point PET melt is transported to the metering pump through a pipeline through a melt filter, the metering pump speed is 10~80r / min, and then sent to the spinning assembly, extruded from the spinneret at 275~290℃, cooled and formed under the action of side blowing at 15~20℃, 4~6kPa, and 72~96m / min, and then introduced into a tubular drawing device with a diameter of 10mm for air flow drawing, and the drawing wind pressure is controlled to be 0.6~0.8MPa, the wind speed is 8000~10000m / min, and the wind temperature is 30~40℃. After exiting the drawing tube, the fibers collide with the inclined swing-blade wire dividing device for wire dividing. The vibration frequency of the swing blade is 800~1000 times / min, and the amplitude is 3~4mm. After hitting the swing blade, the fibers scatter and form a uniform lower fiber web on the net curtain with the assistance of the suction device under the net.

[0018] Furthermore, a glass fiber mesh reinforcement layer is unrolled and laid on the lower fiber web.

[0019] Furthermore, the steps of spinning the upper fiber web into a web are as follows: the low-melting-point PET melt is transported to a metering pump through a pipeline through a melt filter, the metering pump speed is 10~80r / min, and then sent to the spinning assembly, extruded from the spinneret at 140~175°C, cooled and formed under the action of side blowing at 15~20°C, 4~5kPa, and 60~84m / min, and then introduced into a tubular drawing device with a diameter of 10mm for air flow drawing, and the drawing wind pressure is controlled to be 0.4~0.6MPa, the wind speed is 6000~8000m / min, and the wind temperature is 30~40°C. After exiting the drawing tube, the fibers collide with the inclined swing-blade wire dividing device for wire dividing, the vibration frequency of the swing blade is 800~1000 times / min, and the amplitude is 3~4mm. After hitting the swing blade, the fibers scatter and form a uniform upper fiber web on the lower spunbond fiber web and the glass fiber web layer with the assistance of the suction device under the net.

[0020] The tensile strength of the glass fiber mesh is above 2000 MPa. The preparation method is to make glass raw materials into fibers through melting and drawing processes, and then weave these glass fibers into a mesh structure. The strength and stability are further improved through a hot pressing curing process to ensure its durability under high-intensity and long-term use.

[0021] The present invention also provides application of the above melt-spun polyester spunbond composite material in flood control and embankment reinforcement bags.

[0022] Furthermore, the melt-spun polyester spunbond composite material is sewn into a flood control and embankment reinforcement bag, and the low-melting-point PET spunbond fiber mesh is arranged in the inner layer of the flood control and embankment reinforcement bag, and the bag is filled with bentonite.

[0023] The present invention also provides an application of a polyester spunbond composite material for flood control and embankment consolidation bags. The low melting point PET layer is stacked on the inner layer to form a bag, and a certain amount of bentonite is filled in the middle and then heat-sealed to form a flood control and embankment consolidation bag, which can simplify the sealing process and reduce the energy consumption of heat sealing. When in use, the high-strength glass fiber mesh improves its mechanical properties, the PET spunbond nonwoven material provides flexibility and sealing, and is used for flood control and emergency rescue. The porous structure of the polyester spunbond composite material allows water to enter the bag, and the volume of bentonite expands 20 to 30 times after encountering water, which can save the storage space of the flood control and embankment consolidation bag and reduce its weight, playing a vital role in protecting people's lives and property.

[0024] Beneficial Effects

[0025] At present, domestic spunbond plants generally do not have the ability to polymerize raw materials, and all start from slice raw materials. Because PET slice raw materials are made by casting and pelletizing polymer melts in water, slices will contain a certain amount of moisture. If the moisture is not removed, it is easy to hydrolyze at high temperature or form bubble fibers to affect spinning, so it must be dried. Depending on the drying equipment, it generally takes 2-16 hours. After the slices are dried, they must be heated and melted by a screw extruder, and the slice solids are converted into melts, which requires a screw extruder to be equipped and provide heating energy consumption. The present invention has both PET melt polymerization and spunbond production capabilities, and the polymerized melt can be directly passed to a metering pump for spinning. Water will not enter the closed melt transmission channel, so there is no need for slice drying equipment and screw extruders, eliminating the casting and pelletizing, slice drying and melting processes, reducing production costs and improving production efficiency. In addition to removing the cost of slice dryers and screw extruders, the cost per ton can be saved by melt direct spinning compared to the slice method, and the production efficiency can be increased by about 20%.

[0026] The present invention arranges a glass fiber net between a high melting point PET spunbond fiber net and a low melting point PET spunbond fiber net to obtain a melt-spun polyester spunbond composite material, and is used for the first time to prepare a flood control and embankment consolidation bag. If a PET spunbond cloth with the same melting point is used to prepare a sandwich structure, high heat is required during heat sealing, and energy consumption is large. At the same time, the entire heat-sealed part is easily brittle and cracked after plasticization and melting, and bentonite is easy to fall out. The present invention uses a sandwich structure material with high melting point, low melting point and glass fiber net at the same time. When heat sealing, only the melting temperature of the low melting point PET layer needs to be reached, and it can be well heat-sealed, which can save more than 50% of the heat sealing energy consumption. At the same time, only the low melting point layer is bonded together, and the high melting point fiber layer still maintains a fiber state, and will not be brittle and cracked in the heat-sealed part, thereby ensuring the integrity of the flood control and embankment consolidation bag. In addition, the sandwich spunbond nonwoven material has good air permeability and water permeability. After being placed in water for a certain period of time, the bentonite contacts water and absorbs and expands, and the volume becomes larger. Stacking together can play a flood control and fixing role.

[0027] The spinning forming process of the present invention adopts a double S head, and the upper and lower layers of spunbond webs can be adjusted at will, and the flexibility of product design is enhanced; the upper and lower layers of spunbond webs provide flexibility, and the porous structure after needle punching can make water easily penetrate into the bag, and the compact structure after heat treatment can prevent bentonite from falling out. The low melting point PET layer is used as the inner layer of the flood control and embankment consolidation bag, which can reduce the energy consumption of heat sealing, and the middle glass fiber mesh layer can improve the strength, save the storage space of the product, and make the product convenient to transport, with a very high cost performance. At present, there is no report on this polyester spunbond composite material for flood control and embankment consolidation bags and its application. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the preparation process flow of melt-spun polyester spunbond composite materials for flood control and embankment reinforcement bags.

[0029] Figure 2 These are photos of melt-spun polyester spunbond composite materials for flood control and embankment reinforcement bags (a. surface; b. side).

[0030] Explanation of reference numerals: 1. high melting point PET melt; 2. first melt filter; 3. first metering pump; 4. high melting point PET spinning assembly; 5. high melting point PET side blowing cooling; 6. high melting point PET fiber; 7. high melting point PET spinning drawing tube; 8. high melting point PET spinning swing-blade swinging device; 9. high melting point PET fiber net under-net suction device; 1', low melting point PET melt; 2', second melt filter; 3', second metering pump ; 4', low melting point PET spinning assembly; 5', low melting point PET side blowing cooling; 6', low melting point PET fiber; 7', low melting point PET spinning drawing tube; 8', low melting point PET spinning swing-blade swinging device; 9', low melting point PET fiber net under-net suction device; 10, glass fiber net unwinding; 11, net curtain; 12, needle piercing equipment; 13, hot air shaping device; 14, three-roller hot rolling surface calendering machine; 15, winding area. DETAILED DESCRIPTION

[0031] The present invention will be further described below with reference to the embodiments.

[0032] The present invention designs a preparation method of a melt-spun polyester spunbond composite material for flood control and embankment reinforcement bags and its application. A high-melting-point polyethylene terephthalate (PET) melt is formed by polycondensation of purified terephthalic acid (PTA) and ethylene glycol (MEG), and isophthalic acid (IPA) is introduced into the polycondensation system of PTA and MEG to form a low-melting-point PET melt. A double S spunbond device is used to pass the high-melting-point PET melt through a melt filter, a metering pump, a spinning assembly, a cooling blower, and a tubular airflow. The lower fiber web is formed after stretching and laying of the wires by an inclined swing-blade type swinging wire machine, and the unwinding glass fiber mesh layer is used as the middle reinforcement layer. The low-melting-point PET melt is then passed through a melt filter, a metering pump, a spinning assembly, cooling and blowing, a tubular airflow stretching, and a tilted swing-blade type swinging wire machine to form an upper fiber web on the glass fiber web. The sandwich structure fiber web composed of three layers of fiber webs is then reinforced by needle punching, hot air shaping, and three-roller hot rolling and polishing to form a polyester spunbond composite material for flood control and embankment consolidation bags.

[0033] The PET spunbond composite material described in the present invention adopts a one-step melt direct spinning technology and a reinforced sandwich structure. The low- and high-melting-point PET melts are passed through respective conveying pipes, melt filters, and metering pumps to enter the spinning assembly for spinning, and then the upper and lower fiber webs are formed through tubular airflow drawing and inclined swing-blade filament laying technology. A glass fiber net is added during the middle unwinding to increase the layer. The three-layer composite fiber web is subjected to needle-punching, hot air shaping, and three-roller hot rolling and polishing to form a composite material with a sandwich structure. This technology is developed for the first time.

[0034] The one-step melt direct spinning technology eliminates the processes of casting belt pelletizing, slice preparation, slice drying, and screw extruder melting, which greatly reduces the preparation time of spinning melt, reduces equipment costs, shortens the process flow, greatly improves production efficiency, and reduces production costs. The high and low melting point PET melt fibers are spun into a web. The spinning process uses a double S head. The upper and lower layers of spunbond webs can be adjusted at will, which enhances the flexibility of product design. A glass fiber mesh layer is added in the middle, and a porous sandwich structure is formed after acupuncture, so that the product has certain air permeability, water permeability and flexibility. The tight structure after heat treatment can prevent particulate matter from penetrating. When in use, the low melting point PET layer is used as the inner layer of the flood control and embankment consolidation bag, which can simplify the sealing process and reduce the energy consumption of heat sealing. Its porous structure can also allow water to enter the bag, so that the volume of bentonite expands 20 to 30 times after contacting water, which plays a role in flood control and embankment consolidation. At the same time, the middle glass fiber mesh layer can improve the strength, save the storage space of the product, and make the product convenient to transport, which has a very high cost performance. This method is an ideal method for preparing melt-spun polyester spunbond composite materials and for preparing flood prevention and embankment reinforcement materials for flood prevention and emergency rescue.

[0035] Any matters not described in the present invention are applicable to the prior art.

[0036] Specific embodiments of the present invention are given below, but the protection scope of the claims of the invention application is not limited by the specific embodiments.

[0037] Example 1

[0038] (1) The high melting point PET melt with a melting point of 260°C obtained by polycondensation is transported to a melt metering pump through a pipeline through a melt filter, and the speed of the metering pump is controlled to be 50r / min. The melt is then sent to a spinning assembly, and a thin stream of the melt is extruded from a spinneret at 278°C, and cooled and formed under the action of a side blowing air of 17°C, 5kPa, and 72m / min; the cooled filaments are introduced into a tubular drawing device with a diameter of 10mm, and the drawing air pressure is 0.6MPa, the wind speed is 8000m / min, and the wind temperature is 30°C. The drawn fibers are introduced into an inclined swing-blade type wire-separating device, and are scattered after hitting a swing blade with a vibration frequency of 1000 times / min and an amplitude of 3mm, and a uniform lower layer of fiber web is formed on the net curtain with the assistance of a suction device under the net;

[0039] (2) 20g / m 2 The glass fiber mesh is unrolled and laid on the lower layer of high melting point PET spunbond fiber mesh to form an intermediate layer;

[0040] (3) The low-melting-point PET melt with a melting point of 145°C obtained by polycondensation is transported to a melt metering pump through a pipeline through a melt filter, and the speed of the metering pump is controlled to be 40r / min. The melt is then sent to the spinning assembly, and a thin stream of the melt is extruded from the spinneret at 170°C, and cooled and formed under the action of a side-blowing wind at 17°C, 5kPa, and 60m / min; the cooled filaments are introduced into a tubular drawing device with a diameter of 10mm, and the drawing wind pressure is 0.5MPa, the wind speed is 6000m / min, and the wind temperature is 30°C. The drawn fibers are introduced into an inclined swing-blade type wire-separating device, and are scattered after hitting a swing blade with a vibration frequency of 1000 times / min and an amplitude of 3mm. They are laid on a glass fiber net with the assistance of an under-net suction device to form a uniform upper fiber net;

[0041] (4) The three-layer fiber web is sent into a needle punching machine with a single needle board and a needle density of 6000 pieces / m, and the needle punching density is 400 needles / cm 2 , and then sent into a hot air device with a hot air temperature of 150℃ for shaping, and then sent to a three-roll hot rolling area with a cotton roller in the middle and smooth rollers on the upper and lower sides for surface polishing, the upper roller temperature is 125℃, and the lower roller temperature is 215℃. After cooling, the edges are trimmed and wound to obtain a melt-spun polyester spunbond composite material for flood control and embankment consolidation bags.

[0042] According to "GB / T 24218.1-2009 Textile nonwoven fabric test methods Part 1: Determination of mass per unit area", the product weight is 125g / m 2 ; According to "GB / T 24218.2-2009 Textiles - Test Methods for Nonwovens - Part 2: Determination of Thickness", the thickness was measured to be 0.48mm; according to "GB / T 24218.3-2010 Textiles - Test Methods for Nonwovens - Part 3: Determination of Breaking Strength and Elongation at Break", the longitudinal tensile strength was measured to be 398N / 5cm, the elongation was 35%, the transverse tensile strength was 328N / 5cm, the elongation was 38%; according to "GB / T 24218.15-2018 Textiles - Test Methods for Nonwovens - Part 15: Determination of Air Permeability", the air permeability was measured to be 1304mm / s.

[0043] Example 2

[0044] The melt-spun polyester spunbond composite material obtained in Example 1 was cut into sheets of 60 cm × 160 cm, the low-melting-point PET layer was folded in half on the inner side into two layers of 60 cm × 80 cm, 5 kg of bentonite was added in the middle, and the non-woven fabric heat sealing machine was used for sealing. The sealing temperature was set to 160°C, the heat sealing pressure was 0.5 MPa, and the heat sealing time was 100 seconds. A flood control embankment reinforcement bag was obtained and immersed in water. After 5 minutes, the bentonite completely expanded and filled the bag, and the volume no longer changed.

[0045] Example 3

[0046] (1) The high melting point PET melt with a melting point of 260°C obtained by polycondensation is transported to a melt metering pump through a pipeline through a melt filter, and the speed of the metering pump is controlled to be 60r / min. The melt is then sent to a spinning assembly, and a thin stream of the melt is extruded from a spinneret at 280°C, and cooled and formed under the action of a side blowing air of 17°C, 5kPa, and 84m / min; the cooled filaments are introduced into a tubular drawing device with a diameter of 10mm, and the drawing air pressure is 0.8MPa, the wind speed is 10000m / min, and the wind temperature is 30°C. The drawn fibers are introduced into an inclined swing-blade type wire separation device, and are scattered after hitting a swing blade with a vibration frequency of 900 times / min and an amplitude of 4mm. With the assistance of a suction device under the net, a uniform lower layer of fiber web is formed on the net curtain;

[0047] (2) 20g / m 2 The glass fiber mesh is unrolled and laid on the lower layer of high melting point PET spunbond fiber mesh to form an intermediate layer;

[0048] (3) The low-melting-point PET melt with a melting point of 115°C obtained by polycondensation is transported to a melt metering pump through a pipeline through a melt filter, and the speed of the metering pump is controlled to be 50r / min. The melt is then sent to the spinning assembly, and a thin stream of the melt is extruded from the spinneret at 140°C, and cooled and formed under the action of a side-blowing wind at 17°C, 4kPa, and 72m / min; the cooled filaments are introduced into a tubular drawing device with a diameter of 10mm, and the drawing wind pressure is 0.6MPa, the wind speed is 5000m / min, and the wind temperature is 30°C. The drawn fibers are introduced into an inclined swing-blade wire-separating device, and are scattered after hitting a swing blade with a vibration frequency of 900 times / min and an amplitude of 4mm. They are laid on a glass fiber net with the assistance of an under-net suction device to form a uniform upper fiber net;

[0049] (4) The three-layer fiber web is sent into a needle punching machine with a single needle board and a needle density of 6000 pieces / m, and the needle punching density is 450 needles / cm 2 , and then sent into a hot air device with a hot air temperature of 130℃ for shaping, and then sent to a three-roll hot rolling area with a cotton roller in the middle and smooth rollers on the upper and lower rollers for surface ironing, the upper roller temperature is 112℃, and the lower roller temperature is 220℃. After cooling, the edges are trimmed and wound to obtain a melt-spun polyester spunbond composite material for flood control and embankment consolidation bags.

[0050] According to "GB / T 24218.1-2009 Textile nonwoven fabric test methods Part 1: Determination of mass per unit area", the product weight is 138g / m 2; According to "GB / T 24218.2-2009 Textiles - Test Methods for Nonwovens - Part 2: Determination of Thickness", the thickness was measured to be 0.54mm; according to "GB / T 24218.3-2010 Textiles - Test Methods for Nonwovens - Part 3: Determination of Breaking Strength and Elongation at Break", the longitudinal tensile strength was measured to be 426N / 5cm, the elongation was 33%, the transverse tensile strength was 346N / 5cm, and the elongation was 37%; according to "GB / T 24218.15-2018 Textiles - Test Methods for Nonwovens - Part 15: Determination of Air Permeability", the air permeability was measured to be 1258mm / s.

[0051] Example 4

[0052] The melt-spun polyester spunbond composite material obtained in Example 3 was cut into sheets of 60 cm × 160 cm, the low-melting point PET layer was folded in half on the inner side into two layers of 60 cm × 80 cm, 5 kg of bentonite was added in the middle, and the non-woven fabric heat sealing machine was used for sealing. The sealing temperature was set to 130°C, the heat sealing pressure was 0.4 MPa, and the heat sealing time was 120 seconds. A flood control embankment reinforcement bag was obtained and immersed in water. After 6 minutes, the bentonite completely expanded and filled the bag, and the volume no longer changed.

[0053] Example 5

[0054] (1) The high melting point PET melt with a melting point of 256°C obtained by polycondensation is transported to a melt metering pump through a pipeline through a melt filter, and the speed of the metering pump is controlled to be 35r / min. The melt is then sent to a spinning assembly, and a thin stream of the melt is extruded from a spinneret at 282°C, and cooled and formed under the action of a side blowing air of 17°C, 4kPa, and 68m / min; the cooled filaments are introduced into a tubular drawing device with a diameter of 10mm, and the drawing air pressure is 0.7MPa, the wind speed is 8000m / min, and the wind temperature is 30°C. The drawn fibers are introduced into an inclined swing-blade type wire separation device, and are scattered after hitting a swing blade with a vibration frequency of 800 times / min and an amplitude of 4mm. With the assistance of a suction device under the net, a uniform lower layer of fiber web is formed on the net curtain;

[0055] (2) 20g / m 2 The glass fiber mesh is unrolled and laid on the lower layer of high melting point PET spunbond fiber mesh to form an intermediate layer;

[0056] (3) The low-melting-point PET melt with a melting point of 128°C obtained by polycondensation is transported to a melt metering pump through a pipeline through a melt filter, and the speed of the metering pump is controlled to be 30 r / min. The melt is then sent to the spinning assembly, and a thin stream of the melt is extruded from the spinneret at 150°C, and cooled and formed under the action of a side-blowing wind at 17°C, 4 kPa, and 68 m / min; the cooled filaments are introduced into a tubular drawing device with a diameter of 10 mm, and the drawing wind pressure is 0.5 MPa, the wind speed is 5000 m / min, and the wind temperature is 30°C. The drawn fibers are introduced into an inclined swing-blade wire-separating device, and are scattered after hitting a swing blade with a vibration frequency of 800 times / min and an amplitude of 4 mm. They are laid on a glass fiber net with the assistance of an under-net suction device to form a uniform upper fiber net;

[0057] (4) The three-layer fiber web is sent into a needle punching machine with a single needle board and a needle density of 6000 pieces / m, and the needle punching density is 380 needles / cm 2 , and then sent into a hot air device with a hot air temperature of 135°C for shaping, and then sent to a three-roll hot rolling area with a cotton roller in the middle and smooth rollers on the upper and lower rollers for surface ironing, the upper roller temperature is 132°C, and the lower roller temperature is 210°C. After cooling, the edges are trimmed and wound to obtain a melt-spun polyester spunbond composite material for flood control and embankment consolidation bags.

[0058] According to "GB / T 24218.1-2009 Textile nonwoven fabric test methods Part 1: Determination of mass per unit area", the product weight is 110g / m 2 ; According to "GB / T 24218.2-2009 Textiles - Test Methods for Nonwovens - Part 2: Determination of Thickness", the thickness was measured to be 0.41mm; according to "GB / T 24218.3-2010 Textiles - Test Methods for Nonwovens - Part 3: Determination of Breaking Strength and Elongation at Break", the longitudinal tensile strength was measured to be 347N / 5cm, the elongation was 38%, the transverse tensile strength was 283N / 5cm, and the elongation was 34%; according to "GB / T 24218.15-2018 Textiles - Test Methods for Nonwovens - Part 15: Determination of Air Permeability", the air permeability was measured to be 1406mm / s.

[0059] Example 6

[0060] The melt-spun polyester spunbond composite material obtained in Example 5 was cut into sheets of 60 cm × 160 cm, the low-melting-point PET layer was folded in half on the inner side into two layers of 60 cm × 80 cm, 5 kg of bentonite was added in the middle, and the non-woven fabric heat sealing machine was used for sealing. The sealing temperature was set to 140°C, the heat sealing pressure was 0.4 MPa, and the heat sealing time was 100 seconds. A flood control embankment reinforcement bag was obtained and immersed in water. After 4 minutes, the bentonite completely expanded and filled the bag, and the volume no longer changed.

[0061] It can be seen from the above embodiments that the present invention adopts a sandwich structure material with both high melting point and low melting point and glass fiber mesh, and has a good heat sealing effect. At the same time, the flood control embankment consolidation bag has good air permeability and water permeability. After being placed in water for a certain period of time, the bentonite contacts with water and absorbs and expands, and its volume grows. When stacked together, it can play a flood control and fixing role.

[0062] Example 7

[0063] Figure 1 The present invention is a schematic diagram of the preparation process of melt-spun polyester spunbond composite materials for flood control and embankment reinforcement bags. The melt-spun polyester spunbond composite material production device for flood control and embankment reinforcement bags of the present invention comprises a melt conveying pipeline, melt filters 2 and 2', metering pumps 3 and 3', spinning components 4 and 4', high melting point PET side blowing cooling 5 and 5', spinning drafting tubes 7 and 7', swing-blade swinging wire devices 8 and 8', net suction devices 9 and 9', glass fiber net unwinding 10, net curtain 11, needle punching machine 12, hot air shaping equipment 13, and three-roller surface calendering machine 14.

[0064] The first melt filter 2, the first metering pump 3, the high melting point PET spinning assembly 4, the high melting point PET side blowing cooling 5, the high melting point PET spinning drawing tube 7, the high melting point PET spinning swing-blade swinging device 8, and the web-forming curtain 11 (the suction device under the high melting point PET fiber web 9) are connected in sequence to form a high melting point PET spinning web-forming device; the second melt filter 2', the second metering pump 3', the low melting point PET spinning assembly 4', the low melting point PET side blowing cooling 5', the low melting point PET spinning drawing tube 7', the low melting point PET spinning swing-blade swinging device 8', and the web-forming curtain 11 (the suction device under the low melting point PET fiber web 9') are connected in sequence to form a low melting point PET spinning web-forming device.

[0065] The first melt filter 2 and the second melt filter 2' are used to filter impurities in the melt and remove bubbles; the first metering pump 3 and the second metering pump 3' are melt output control devices, which are used to accurately meter and output the polymer melt for spinning.

[0066] The high melting point PET melt obtained by polycondensation is transported to the first melt filter 2 and the first metering pump 3 through a pipeline, and then sent to the spinning assembly 4, extruded from the spinneret at 275-290°C, cooled and formed under the action of the side blowing air 5 at 15-20°C, 4-6kPa, and 72-96m / min, and then introduced into the tubular drawing device 7 with a diameter of 10mm for air flow drawing, and the drawing air pressure is controlled to be 0.6-0.8MPa, the wind speed is 8000-10000m / min, and the wind temperature is 30-40°C. After exiting the drawing tube, the fibers collide with the inclined swing-blade wire-splitting device 8 for wire separation, and the vibration frequency of the swing blade is 800-1000 times / min and the amplitude is 3-4mm. After the fibers collide with the swing blade, they are scattered and separated, and a uniform lower fiber web is formed on the net curtain with the assistance of the under-net suction device 9; the low melting point PET obtained by polycondensation The ET melt is transported to the second melt filter 2' and the second metering pump 3' through a pipeline, and then sent to the spinning assembly 4', extruded from the spinneret at 140~175℃, cooled and formed under the action of the side blowing air 5' at 15~20℃, 4~5kPa, and 60~84m / min, and then introduced into the tubular drawing device 7' with a diameter of 10mm for air flow drawing, and the drawing wind pressure is controlled to be 0.4~0.6MPa, the wind speed is 6000~8000m / min, and the wind temperature is 30~40℃. After leaving the drawing tube, the fibers hit the inclined swing-blade type wire separation device 8' for wire separation. The vibration frequency of the swing blade is 800~1000 times / min and the amplitude is 3~4mm. After hitting the swing blade, the fibers scatter and form a uniform upper fiber web on the lower spunbond fiber web and the glass fiber web layer with the assistance of the under-net suction device 9'.

[0067] The side-blowing cooling devices 5 and 5' cool and form the extruded melt streams to prevent the fibers from sticking to each other; the tubular drawing devices 7 and 7' complete the drawing of the fibers, increase the fiber orientation and crystallinity, and give the fibers strength and other properties; the swing-blade wire-splitting devices 8 and 8' are installed at an angle and operate at high speed to complete the fiber separation and improve the uniformity of the web, and form a uniform fiber web on the web-forming curtain 11 with the assistance of the under-web suction devices 9 and 9'. The under-net suction devices 9 and 9' are used to assist in web formation, and the suction is directed to the thin parts of the web to ensure the uniformity of web formation; the glass fiber unwinding 10 is used to form the middle layer of the glass fiber web, which is a filament web and is used to improve the mechanical properties of the material; the needle-punching web fixing machine 12 is used for needle-punching web fixing, which provides mechanical properties for the sandwich structure and prevents material stratification; the hot air bonding device 13 performs heat setting on the material, relaxes the internal stress formed during the spinning and drawing process, improves the mechanical properties of the material, and improves the compactness of the material structure; the three-roll hot-calender bonding machine 14 is used for polishing the surface of the material to improve the stiffness and surface finish of the material.

[0068] Figure 2These are photos of melt-spun polyester spunbond composite materials used in flood control and embankment reinforcement bags. Figure (a) is a surface photo, with the top layer removed from the upper left corner, revealing the middle glass fiber mesh layer; Figure (b) is a cross-sectional photo, showing a layer of glass fiber mesh sandwiched between the upper and lower layers of spunbond fiber mesh.

Claims

1. A melt-spun polyester spunbond composite material, characterized in that: The material comprises two layers of melt-spun PET spunbond web and one layer of glass fiber web, wherein the melt-spun PET spunbond web comprises two layers, the lower layer is a high-melting-point PET spunbond web, the upper layer is a low-melting-point PET spunbond web, and the middle layer is a glass fiber web.

2. The melt-spun polyester spunbond composite material according to claim 1, characterized in that: The high melting point PET spunbond web is prepared by esterifying purified terephthalic acid and ethylene glycol to generate ethylene terephthalate, and then polycondensing to obtain a high melting point PET melt, which is then spun into a web, and the melting point of the melt is 250-260°C; the low melting point PET spunbond web is prepared by polycondensing isophthalic acid into a purified terephthalic acid and ethylene glycol polymerization system to obtain a low melting point PET melt, which is then spun into a web, and the melting point of the melt is 110-150°C.

3. The melt-spun polyester spunbond composite material according to claim 1, characterized in that: The melt-spun polyester spunbond composite material has a unit area mass of 90-140 g / m 2 The upper layer of low melting point PET spunbond fiber has a unit area mass of 30~50g / m 2 The mass per unit area of ​​the middle layer of glass fiber mesh is 20~30g / m 2 The unit area mass of the lower layer high melting point PET spunbond web is 40~60g / m 2 .

4. The melt-spun polyester spunbond composite material according to claim 1, characterized in that: The melt-spun polyester spunbond composite material has a thickness of 0.40-0.60 mm, a longitudinal tensile strength of 300-500 N / 5 cm, an elongation of 30-40%, a transverse tensile strength of 200-350 N / 5 cm, an elongation of 35-45%, and an air permeability of 1200-1500 mm / s.

5. The method for preparing the melt-spun polyester spunbond composite material according to claim 1, characterized in that: The preparation method comprises: using a double S-head spunbond device, introducing a high-melting-point PET melt into a material path system of a lower spunbond head, and then forming a lower fiber web on a mesh curtain after metering by a metering pump, spinning by a spinning assembly, cooling and forming, airflow drawing, and filament separation; unwinding a glass fiber web and laying it on a high-melting-point PET spunbond fiber web layer to form a second fiber web; introducing a low-melting-point PET melt into a material path system of an upper spunbond head, and then metering by a metering pump, spinning by a spinning assembly, cooling and forming, airflow drawing, and filament separation, and then laying it on a glass fiber web to form an upper fiber web; the three-layer composite fiber web is sent to a needle punching machine for needle punching and fixing, and then hot air setting and smooth roller calendering are performed to obtain a melt-spun polyester spunbond composite material.

6. The method for preparing the melt-melt polyester spunbond composite material according to claim 5, characterized in that: The preparation steps of the melt-spun PET spunbond fiber web layer include: conveying the low-melting-point PET melt and the high-melting-point PET melt to a melt filter respectively, and then conveying them to a metering pump with a rotation speed of 10-80 r / min for metering, and then conveying them to a spinning assembly, extruding the low-melting-point PET melt from a spinneret hole at 140-175°C, and extruding the high-melting-point PET from a spinneret hole at 275-290°C, and side-blowing at 15-20°C, 4-6 kPa, and 60-96 m / min. The fibers are cooled and formed under the action of wind, and then air flow drawing is carried out. The drawing wind pressure is controlled to be 0.4~0.8MPa, the wind speed is 6000~10000m / min, and the wind temperature is 30~40℃. After air flow drawing, the fibers collide with the inclined swing-blade type wire dividing device for wire dividing. The vibration frequency of the swing blade is 800~1000 times / min, and the amplitude is 3~4mm. After the fibers collide with the swing blade, they scatter and form a melt-spun PET spunbond fiber web layer on the mesh curtain with the assistance of the suction device under the mesh.

7. The method for preparing the melt-spun polyester spunbond composite material according to claim 5, characterized in that: The needle punching and web fixing step is: sending the sandwich structure web of the upper and lower layers of spunbond web and the glass fiber web in the middle into the needle punching area for needle punching and web fixing, and the needle punching density is 300-500 thorns / cm 2 .

8. The method for preparing the melt-spun polyester spunbond composite material for flood control and embankment reinforcement bags according to claim 5, characterized in that: The hot air setting and smooth roller calendering steps include: sending the composite fiber web after needle punching into a hot air setting area, hot air setting at 120-150°C, and then sending it into a three-roller hot rolling area for surface ironing, wherein the middle roller is a cotton roller, and the upper and lower rollers are smooth rollers, and the temperatures are set to 110-130°C and 180-220°C respectively; after cooling, trimming and winding to obtain a melt-spun polyester spunbond composite material.

9. Use of the melt-spun polyester spunbond composite material according to claim 1 in flood control and embankment reinforcement bags.

10. The use according to claim 9, characterized in that: The melt-spun polyester spunbond composite material is sewn into flood control and embankment reinforcement bags, and the low-melting-point PET spunbond fiber mesh is arranged in the inner layer of the flood control and embankment reinforcement bags, and the bags are filled with bentonite.

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