Permeable porous foaming PVC (polyvinyl chloride) board as well as production method and application thereof

Abstract

The invention provides a water-permeable porous foamed PVC (polyvinyl chloride) board as well as a production method and application thereof, and the PVC board is prepared from the following raw materials in parts by weight: 90-120 parts of matrix resin, 3-8 parts of quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres, 3-8 parts of a dynamic crosslinking type elastomer, 4.3-13.0 parts of a foaming agent, 17-35 parts of a composite stable plasticizer, 3-9 parts of a processing aid and 0.1-0.3 part of an antibacterial agent. The PVC board provided by the invention has the advantages of water permeability, antibacterial property, stable structure and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of PVC plate, in particular to a water-permeable porous foamed PVC plate and its production method and application. BACKGROUND

[0002] With the upgrading of demand in the fields of sponge city construction and medical environment remediation, water-permeable porous materials have become a research hotspot in the field of materials due to their characteristics of drainage, air permeability, noise reduction, etc. PVC plate is widely used in construction, municipal and other scenes due to its advantages of easy availability of raw materials, excellent processability and controllable cost. By preparing water-permeable porous foamed plate, its application range in water-permeable paving, drainage system and other scenes can be further expanded, which meets the requirements of green environmental protection and functional development.

[0003] The PVC plate in the existing general technology is mostly of dense structure. Even for some water-permeable modified products, pores are often constructed by simply adding inorganic fillers. Such PVC plates generally have the problem that water permeability and structural stability are difficult to balance. Either the pore connectivity is poor, resulting in low water permeability, or the mechanical strength is significantly reduced after the porosity is increased, which cannot meet the long-term use requirements. SUMMARY

[0004] In view of the problems in the prior art, the present application provides a water-permeable porous foamed PVC plate and its production method and application.

[0005] To achieve the above purpose, the present application realizes the following technical solutions:

[0006] The present application discloses a water-permeable porous foamed PVC plate, the composition of which includes, in parts by weight: base resin 90-120 parts, quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres 3-8 parts, dynamic crosslinking elastomer 3-8 parts, foaming agent 4.3-13.0 parts, composite stabilizing plasticizer 17-35 parts, processing aid 3-9 parts, and antibacterial agent 0.1-0.3 parts.

[0007] By using the above technical solutions, the base resin can give the material basic formability and construct a mechanical skeleton; the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres can construct water-permeable channels and play an antibacterial role; the dynamic crosslinking elastomer can improve the toughness and melt strength of the material, ensuring the structural stability; the foaming agent can help form a porous structure and synergistically optimize the water permeability; the composite stabilizing plasticizer has the effects of inhibiting material degradation and improving processing fluidity; the processing aid can ensure smooth processing; and the antibacterial agent can enhance the antibacterial efficiency. The synergistic effect of the components makes the PVC plate have the advantages of water permeability, antibacterial property, easy formability and structural stability.

[0008] Preferably, the base resin comprises 70-85 parts by weight of polyvinyl chloride (PVC) resin, 10-20 parts by weight of chlorinated polyvinyl chloride (CPVC), and 10-15 parts by weight of recycled polyvinyl chloride (r-PVC, which refers to a regenerated raw material that can restore or approach the processing performance of virgin PVC after conventional pretreatment such as crushing, impurity removal, and drying); the foaming agent comprises 4-12 parts by weight of a composite chemical foaming agent and 0.3-1.0 parts by weight of a water-based physical foaming agent; the composite chemical foaming agent is compounded from azodicarbonamide and 4,4'-oxybisbenzenesulfonylhydrazide at a mass ratio of 1:(1.2-1.5), and the water-based physical foaming agent is compounded from sodium bicarbonate and citric acid at a molar ratio of 1:(1.2-1.5).

[0009] The PVC resin can impart the material with basic formability and a mechanical skeleton, the CPVC can improve the compatibility with other components in the system by virtue of its polarity, and the r-PVC, as a regenerated raw material, can reduce the cost of raw materials while ensuring processing performance; the azodicarbonamide and 4,4'-oxybisbenzenesulfonylhydrazide in the composite chemical foaming agent are compounded at a specific ratio to achieve synergistic gas production, and the sodium bicarbonate and citric acid in the water-based physical foaming agent are compounded at a specific molar ratio to also produce gas, the two types of foaming agents work together to provide a guarantee for the formation of a porous structure in the material, and the base resin components and the foaming agent components work together to ensure that the material has both processability and a basic porous structure.

[0010] Preferably, the PVC resin has a weight-average molecular weight of 80,000-120,000 Da; the CPVC has a chlorine content of 63%-68% and a weight-average molecular weight of 90,000-130,000 Da; and the r-PVC has an impurity content of ≤0.5%, a weight-average molecular weight of 60,000-90,000 Da, and a residual vinyl chloride monomer content of ≤0.5%.

[0011] The PVC resin with a weight-average molecular weight of 80,000-120,000 Da can ensure its basic formability and the ability to construct a mechanical skeleton as a base resin; the CPVC with a chlorine content of 63%-68% can enhance its polarity, and a weight-average molecular weight of 90,000-130,000 Da is conducive to improving the compatibility with other components and the heat resistance of the material; the impurity content of ≤0.5% and the residual vinyl chloride monomer content of ≤0.5% of the r-PVC can avoid adverse effects of impurities and residual monomers on the performance of the material, and a weight-average molecular weight of 60,000-90,000 Da enables the r-PVC to reduce the cost of raw materials while better adapting to the base system, ensuring overall forming processing and basic performance stability.

[0012] Preferably, the composition of the composite stabilizing plasticizer includes 2-5 parts of organotin carboxylate composite stabilizer, 5-14 parts of trioctyl trimellitate, 5-9 parts of tributyl citrate and 5-7 parts of epoxy fatty acid methyl ester, by weight of the total components; the organotin carboxylate composite stabilizer is one of methyl tin carboxylate or octyl tin carboxylate; the processing aid is compounded by an acrylic ester processing aid (ACR) and a composite lubricant at a mass ratio of 2:1, and the composite lubricant is compounded by oxidized polyethylene wax and calcium stearate at a mass ratio of 1:1; the antibacterial agent is a nano-silver antibacterial agent with a particle size of 20-50 nm and an effective silver content of ≥99.0%.

[0013] The methyl tin carboxylate or octyl tin carboxylate can inhibit the thermal degradation of polyvinyl chloride, the trioctyl trimellitate, the tributyl citrate and the epoxy fatty acid methyl ester can synergistically play a plasticizing role to improve the processing fluidity, and the composite stabilizing plasticizer composed of the above components can have both stabilizing and plasticizing functions; the processing aid compounded by the acrylic ester processing aid (ACR) and the composite lubricant (1:1 compounded by oxidized polyethylene wax and calcium stearate) at a mass ratio of 2:1 can improve the melt performance through the ACR and ensure smooth processing through the composite lubricant; the nano-silver antibacterial agent with a particle size of 20-50 nm and an effective silver content of ≥99.0% can have an antibacterial effect, and the components can synergistically ensure the material processing stability and antibacterial function.

[0014] Preferably, the composition of the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres includes 90-100 parts of diatomite, 15-25 parts of perfluorohexyl ethyl acrylate, 5-10 parts of vinyl trimethoxysilane, 3-5 parts of methacryloyloxyethyl trimethyl ammonium chloride, 0.5-1.5 parts of di-tert-butyl peroxide and 400-600 parts of anhydrous ethanol, by weight.

[0015] The diatomite provides a porous substrate for the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres, lays a foundation for the construction of water permeable channels; the perfluorohexyl ethyl acrylate can introduce fluorine segments to improve the compatibility of the microspheres with the matrix and other components; the vinyl trimethoxysilane helps the grafting of functional groups to the diatomite; the methacryloyloxyethyl trimethyl ammonium chloride provides quaternary ammonium salt groups to endow the microspheres with antibacterial and antifouling functions; the di-tert-butyl peroxide as an initiator can start a multi-functional grafting reaction to ensure the synchronous grafting of various functional groups; and the anhydrous ethanol as a solvent can realize the uniform dispersion of the raw materials to ensure the smooth reaction, so that the microspheres finally have the comprehensive effects of rigid porous, water permeable, antibacterial and good compatibility.

[0016] Preferably, the preparation method of the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres includes the following steps:

[0017] 1) Diatomite is added into anhydrous ethanol, and ultrasonic dispersion is carried out at 60-70 DEG C, a frequency of 20-40 kHz, and an ultrasonic power of 150-200 W for 60-90 min, during which stirring is carried out at a speed of 250-350 r / min for 1-2 min every 15-25 min to obtain a uniform suspension;

[0018] 2) Full-hexyl ethyl acrylate, vinyl trimethoxysilane, methacryloyloxyethyl trimethyl ammonium chloride, and di-tert-butyl peroxide are sequentially added into the suspension, nitrogen gas with a purity of greater than or equal to 99.99% is introduced at a flow rate of 100-150 mL / min, and bubbling is carried out for 25-35 min, followed by heating to 75-85 DEG C under nitrogen protection, and constant temperature stirring is carried out at 200-300 r / min for 4-6 h;

[0019] 3) After the reaction solution is cooled to room temperature, centrifugal separation is carried out at a speed of 2500-4500 r / min for 15-20 min, the obtained solid is washed with anhydrous ethanol for 3 times, each time using an amount of 1.5-2.5 times the volume of the solid, and then the washed solid is dried under vacuum at 80-90 DEG C and a pressure of -0.09~-0.095 MPa for 8-12 h until the weight is constant, and then the product is crushed by an air flow crusher and sieved through a 240-260 mesh standard sieve to obtain the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres.

[0020] By the above technical solution, the diatomite is uniformly dispersed in anhydrous ethanol by the combination of ultrasonic dispersion and stirring, thereby providing a stable substrate for subsequent reactions; the introduction of nitrogen gas can remove oxygen in the system, thereby ensuring the smooth progress of the grafting reaction; the synchronous grafting of full-hexyl ethyl acrylate, vinyl trimethoxysilane, and methacryloyloxyethyl trimethyl ammonium chloride on the diatomite is achieved by constant temperature stirring; the unreacted raw materials and impurities can be removed by centrifugation and anhydrous ethanol washing, thereby improving the purity of the product; vacuum drying ensures that the product is dried to a constant weight; crushing and sieving control the uniformity of the particle size of the microspheres; and finally, the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres with good dispersibility, high purity, and controllable particle size, and having fluorine chain segment compatibility, quaternary ammonium salt antibacterial property, and diatomite porous structure, can be prepared.

[0021] Preferably, the dynamic crosslinking type elastomer is composed of, in parts by weight, polyvinylidene fluoride-hexafluoropropylene copolymer particles 56-64, bio-based polycaprolactone particles 16-24, 2,2'-dithiodibenzoic acid 10-15, zinc acrylate 5-10, dicumyl peroxide 0.1-0.3, and dimethylbenzene 200-300; the weight average molecular weight of the polyvinylidene fluoride-hexafluoropropylene copolymer particles is 100000-150000 Da, and the content of hexafluoropropylene is 10%-15%; the number average molecular weight of the bio-based polycaprolactone particles is 10000-20000 Da, and the bio-based carbon content is greater than or equal to 95%.

[0022] With the above technical solution, the polyvinylidene fluoride-hexafluoropropylene copolymer particles can provide hydrophobic function and basic elasticity, and the specific molecular weight and hexafluoropropylene content ensure the compatibility with other components; the bio-based polycaprolactone particles achieve bio-based modification with high bio-based carbon content, reduce the amount of fluorinated compounds, and the ester bond can participate in crosslinking reaction; 2,2'-dithiodibenzoic acid and zinc acrylate respectively provide disulfide bond and carboxylic acid zinc coordination bond, and the two form a reversible crosslinking network in cooperation; the dicumyl peroxide as an initiator can start the grafting and crosslinking reaction; the xylene as a solvent can realize uniform dissolution of each raw material, ensure the uniformity of the reaction, and finally make the prepared dynamic crosslinking elastomer have dynamic crosslinking performance, hydrophobic function and bio-based characteristics, which can improve the melt strength and material toughness.

[0023] Preferably, the preparation method of the dynamic crosslinking elastomer comprises the following steps:

[0024] (1) Add xylene into the reaction kettle, heat to 120-130℃, add polyvinylidene fluoride-hexafluoropropylene copolymer particles and bio-based polycaprolactone particles, and stir at a speed of 200-300 r / min under nitrogen protection for 2-3 h to make the materials completely dissolved;

[0025] (2) Add 2,2'-dithiodibenzoic acid, zinc acrylate and dicumyl peroxide into the solution obtained in (1) in sequence, and stir at a speed of 250-300 r / min at 125-135℃ for 3-5 h;

[0026] (3) Cool the reaction liquid obtained in (2) to below 60℃, pour the reaction liquid into methanol at a volume ratio of reaction liquid to methanol of 1:(8-12), stir at a speed of 500-800 r / min for 20-30 min, filter and collect the product, wash the product with methanol for 3 times, each time with an amount of 2.5-3.5 times the volume of the solid, then dry the product under vacuum conditions of 70-80℃ and -0.09~-0.095 MPa for 24-36 h to constant weight, and crush to obtain the dynamic crosslinking elastomer.

[0027] With the above technical solution, oxygen interference is excluded by nitrogen protection, ensuring the smooth progress of the reaction, and heating and stirring make the polyvinylidene fluoride-hexafluoropropylene copolymer particles and bio-based polycaprolactone particles completely dissolved in xylene to form a uniform solution, laying a foundation for the uniformity of the subsequent reaction; through stirring reaction at a specific temperature, 2,2'-dithiodibenzoic acid, zinc acrylate and dicumyl peroxide are fully reacted to form a reversible crosslinking network; methanol is used to realize the flocculation and precipitation of the product, and the unreacted raw materials and impurities are removed by washing to improve the purity of the product, and vacuum drying ensures that the product is free of residual solvent and dried to constant weight, finally a dynamic crosslinking elastomer with high purity, stable crosslinking structure and uniform properties can be prepared.

[0028] The application also discloses a production method of the water-permeable porous foamed PVC plate.

[0029] S1, raw material pretreatment and pre-homogenization:

[0030] S11, crushing the recycled polyvinyl chloride and passing through an 80-90 mesh sieve, and then drying the PVC resin and CPVC together in a hot air circulating oven at 85-90 DEG C for 3-4 h, controlling the water content of the material to be less than or equal to 0.1%;

[0031] S12, weighing the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres and the nano-silver antibacterial agent, and pre-mixing at a speed of 1000-1200 r / min for 5-8 min;

[0032] S13, adding the material obtained in S11, the pre-mixed material obtained in S12 and the remaining material into a high-speed thermal mixer, first mixing at a speed of 800-1000 r / min for 4-6 min, and then mixing at a speed of 1200-1500 r / min at 110-120 DEG C for 10-15 min, and cooling to a material temperature of less than or equal to 40 DEG C;

[0033] S2, blending and synergistic foaming:

[0034] adding the mixture obtained in S13 into a co-rotating parallel twin-screw extruder, adjusting the temperature settings of each section of the extruder to be: zone 1 130-140 DEG C, zone 2 145-155 DEG C, zone 3 155-165 DEG C, zone 4 160-170 DEG C, and the die head 165-175 DEG C, and the screw speed is 200-300 r / min; after pressure stabilization by the melt pump, the material is sent to a single-screw extruder, supercritical carbon dioxide is pressurized to 10-16 MPa and heated to 38-42 DEG C, and then injected into the middle of the single-screw extruder at a rate of 1.0-2.0 phr (phr, i.e. per hundred parts of resin), and then homogenized by a static mixer and a melt;

[0035] S3, molding:

[0036] The foamed melt obtained in S2 is extruded from a wide flat plate die, the die lip opening is 1.5-2.5 times the thickness of the finished product, and then introduced into a three-roll calender, the calender roll temperatures are respectively 75-85 DEG C for the first roll, 55-65 DEG C for the second roll, and 35-45 DEG C for the third roll, and the roll gap pressure is 5-8 MPa; the calendered plate is cooled to less than or equal to 40 DEG C by a multi-section cooling roller group, drawn at a uniform speed of 1.5-2.5 m / min by a traction machine, and then cut to a fixed length to obtain the finished product.

[0037] The technical scheme is adopted, the recycled polyvinyl chloride is crushed and screened, and is co-dried with polyvinyl chloride resin and chlorinated polyvinyl chloride, impurities and moisture (water content is controlled to be less than or equal to 0.1 %) are effectively removed, and defects are avoided in subsequent processing; the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres are premixed with the nano-silver antibacterial agent, and subsequent high-speed thermal mixing, cooling treatment is carried out, uniform fusion of the materials is ensured, and the antibacterial components are prevented from agglomeration and moisture absorption; the temperature setting and speed regulation of the double-screw extruder realize sufficient plasticization and dispersion of the materials, the melt pump stabilizes the pressure to ensure stable melt conveying, the supercritical carbon dioxide is pressurized and heated to be injected, and then is homogenized by the static mixer, and can be uniformly foamed with the foaming agent; the wide flat plate die extrusion is matched with the three-roller calender temperature gradient regulation and the roll gap pressure control, the plate forming is ensured to be regular and the thickness is uniform, and subsequent cooling, uniform speed traction and fixed length cutting ensure the size precision of the finished product, and finally the water-permeable porous foamed PVC plate with uniform component dispersion, stable bubble structure and qualified forming quality is prepared.

[0038] The application further discloses an application of the water-permeable porous foamed PVC plate in sponge city water-permeable pavement, highway subgrade drainage belt, ecological slope protection drainage filter layer, industrial floor moisture-proof cushion layer and sports ground foundation drainage layer.

[0039] The technical scheme is adopted, the recycled polyvinyl chloride is crushed and screened, and is co-dried with polyvinyl chloride resin and chlorinated polyvinyl chloride, impurities and moisture (water content is controlled to be less than or equal to 0.1 %) are effectively removed, and defects are avoided in subsequent processing; the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres are premixed with the nano-silver antibacterial agent, and subsequent high-speed thermal mixing, cooling treatment is carried out, uniform fusion of the materials is ensured, and the antibacterial components are prevented from agglomeration and moisture absorption; the temperature setting and speed regulation of the double-screw extruder realize sufficient plasticization and dispersion of the materials, the melt pump stabilizes the pressure to ensure stable melt conveying, the supercritical carbon dioxide is pressurized and heated to be injected, and then is homogenized by the static mixer, and can be uniformly foamed with the foaming agent; the wide flat plate die extrusion is matched with the three-roller calender temperature gradient regulation and the roll gap pressure control, the plate forming is ensured to be regular and the thickness is uniform, and subsequent cooling, uniform speed traction and fixed length cutting ensure the size precision of the finished product, and finally the water-permeable porous foamed PVC plate with uniform component dispersion, stable bubble structure and qualified forming quality is prepared.

[0040] The application has the following beneficial effects:

[0041] The base resin can give the material basic formability and build a mechanical skeleton; the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres can build water-permeable channels and play an antibacterial role; the dynamic crosslinking elastomer can improve the toughness and melt strength of the material, and ensure the structural stability; the foaming agent can help form a porous structure and cooperatively optimize the water-permeability; the composite stabilizing plasticizer has the effects of inhibiting material degradation and improving processing fluidity; the processing aid can ensure smooth processing; the antibacterial agent can enhance the antibacterial efficiency, and the synergistic effect of the components makes the PVC plate have the advantages of water permeability, antibacterial property, easy formability and structural stability.

[0042] The diatomite provides a porous base for the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres, lays the foundation for the construction of water permeable channels; the perfluorohexyl ethyl acrylate can introduce fluorine segments to improve the compatibility of the microspheres with the matrix and other components; the vinyl trimethoxysilane helps the grafting of functional groups and diatomite; the methacryloyloxyethyl trimethyl ammonium chloride provides quaternary ammonium salt groups, endows the microspheres with antibacterial and antifouling functions; the di-tert-butyl peroxide as an initiator can start the multi-functional grafting reaction, and ensure the synchronous grafting of various functional groups; the anhydrous ethanol as a solvent can realize the uniform dispersion of various raw materials, ensure the smooth reaction, and finally make the microspheres have the comprehensive effects of rigid porous, water permeable, antibacterial and good compatibility. DETAILED DESCRIPTION

[0043] To make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0044] Embodiment 1

[0045] The embodiment discloses a water-permeable porous foamed PVC plate, and the component raw materials of the water-permeable porous foamed PVC plate include, in parts by weight, 70 parts of PVC resin with a weight average molecular weight of 80000 Da, 10 parts of CPVC, 10 parts of r-PVC, 3 parts of quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres, 3 parts of dynamic crosslinking type elastomer, 4 parts of composite chemical foaming agent, 0.3 parts of water-based physical foaming agent, 2 parts of organotin carboxylate composite stabilizer, 5 parts of trioctyl trimellitate, 5 parts of tributyl citrate, 5 parts of epoxy fatty acid methyl ester, 3 parts of processing aid, and 0.1 part of nano-silver antibacterial agent.

[0046] The CPVC has a chlorine content of 63%, a weight average molecular weight of 90000 Da, an impurity content of r-PVC ≤0.5%, a weight average molecular weight of 60000 Da, and a residual amount of chloroethylene monomer ≤0.5%. The composite chemical foaming agent is compounded by azodicarbonamide and 4,4'-oxobisbenzenesulfonylhydrazide at a mass ratio of 1:1.2, and the water-based physical foaming agent is compounded by sodium bicarbonate and citric acid at a molar ratio of 1:1.2.

[0047] The organotin carboxylate composite stabilizer is one of methyl tin carboxylate or octyl tin carboxylate; the processing aid is compounded by an acrylate processing aid and a composite lubricant at a mass ratio of 2:1, and the composite lubricant is compounded by oxidized polyethylene wax and calcium stearate at a mass ratio of 1:1; the nano-silver antibacterial agent has a particle size of 20-50 nm and an effective silver content ≥99.0%.

[0048] The composition of the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres includes, in parts by weight, diatomite 90, perfluorohexyl ethyl acrylate 15, vinyl trimethoxysilane 5, methacryloyloxyethyl trimethyl ammonium chloride 3, di-tert-butyl peroxide 0.5, and anhydrous ethanol 400.

[0049] The preparation method of the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres includes the following steps:

[0050] 1) Diatomite was added to anhydrous ethanol and ultrasonically dispersed at 60℃ for 60 min under the conditions of a frequency of 20 kHz and an ultrasonic power of 150 W, and during the process, stirring was performed at a speed of 250 r / min for 1 min every 15 min to obtain a uniform suspension;

[0051] 2) Perfluorohexyl ethyl acrylate, vinyl trimethoxysilane, methacryloyloxyethyl trimethyl ammonium chloride, and di-tert-butyl peroxide were sequentially added to the suspension, and nitrogen gas with a purity of ≥99.99% was bubbled at a flow rate of 100 mL / min for 25 min, and then the temperature was raised to 75℃ under nitrogen protection, and constant temperature stirring was performed at a speed of 200 r / min for 4 h;

[0052] 3) After the reaction solution was cooled to room temperature, centrifugal separation was performed at a speed of 2500 r / min for 15 min, the obtained solid was washed with anhydrous ethanol for 3 times, and the amount of anhydrous ethanol used for each washing was 1.5 times the volume of the solid, and then the washed solid was dried under the conditions of 80℃ and a vacuum of -0.09~-0.095 MPa for 8 h to a constant weight, and after being crushed by an air flow crusher, the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres were obtained by passing through a 240 mesh standard sieve.

[0053] The composition of the dynamic crosslinking type elastomer includes, in parts by weight, polyvinylidene fluoride-hexafluoropropylene copolymer particles 56, bio-based polycaprolactone particles 16, 2,2'-dithiodibenzoic acid 10, zinc acrylate 5, dicumyl peroxide 0.1, and dimethylbenzene 200; the weight average molecular weight of the polyvinylidene fluoride-hexafluoropropylene copolymer particles is 100000 Da, and the content of hexafluoropropylene is 10%; the number average molecular weight of the bio-based polycaprolactone particles is 10000 Da, and the bio-based carbon content is ≥95%.

[0054] The preparation method of the dynamic crosslinking type elastomer includes the following steps:

[0055] (1) In a reaction kettle, dimethylbenzene was added, and the temperature was raised to 120℃, and then polyvinylidene fluoride-hexafluoropropylene copolymer particles and bio-based polycaprolactone particles were added, and stirring was performed at a speed of 200 r / min under nitrogen protection for 2 h to completely dissolve the materials;

[0056] (2) adding 2,2'-dithiodibenzoic acid, zinc acrylate and dicumyl peroxide into the solution obtained in (1) in sequence, and stirring the reaction solution at 125℃ and a rotation speed of 250r / min for 3h;

[0057] (3) cooling the reaction solution obtained in (2) to below 60℃, pouring the reaction solution into methanol at a volume ratio of the reaction solution to methanol of 1:8, stirring at a rotation speed of 500r / min for 20min, collecting the product by filtration, washing the product with methanol for 3 times, each time using 2.5 times the volume of the solid, and then drying the product under vacuum conditions of 70℃ and -0.09~-0.095MPa for 24h until the weight is constant, and obtaining the dynamic cross-linked elastomer after crushing.

[0058] The embodiment also discloses a production method of the water-permeable porous foamed PVC plate, comprising the following steps:

[0059] S1, raw material pretreatment and pre-homogenization:

[0060] S11, crushing the r-PVC through an 80-mesh sieve, and then drying the r-PVC, PVC resin and CPVC together in a hot air circulating oven at 85℃ for 3h, and controlling the water content of the material to be ≤0.1%;

[0061] S12, weighing the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres and the nano-silver antibacterial agent, and premixing for 5min at a rotation speed of 1000r / min;

[0062] S13, adding the material obtained in S11, the premixed material obtained in S12 and the remaining material into a high-speed thermal mixer, mixing at a rotation speed of 800r / min for 4min, and then mixing at a rotation speed of 1200r / min for 10min at 110℃, and cooling to a material temperature ≤40℃;

[0063] S2, blending and synergistic foaming:

[0064] adding the mixture obtained in S13 into a co-rotating parallel twin-screw extruder, adjusting the temperature settings of each section of the extruder to be: 130℃ for the first section, 145℃ for the second section, 155℃ for the third section, 160℃ for the fourth section, and 165℃ for the die head, and the screw rotation speed is 200r / min; after pressure stabilization by the melt pump, the material is transferred to a single-screw extruder, supercritical carbon dioxide is pressurized to 10MPa and heated to 38℃, and then injected into the middle part of the single-screw extruder at a rate of 1.0phr, and then homogenized by a static mixer and a melt;

[0065] S3, molding:

[0066] The foaming melt obtained in S2 is extruded from a wide flat plate die, the die lip opening is 1.5 times the thickness of the finished product, and then introduced into a three-roll calender, the calender roll temperature is 75℃, 55℃ and 35℃ respectively, the roll gap pressure is 5MPa; the calendered plate is cooled to ≤40℃ by a multi-section cooling roller group, and then pulled at a uniform speed of 1.5m / min by a traction machine, and the finished product is obtained after cutting to a fixed length.

[0067] The embodiment also discloses an application of the water-permeable porous foamed PVC plate in water-permeable pavement of a sponge city.

[0068] Embodiment 2

[0069] The embodiment discloses a water-permeable porous foamed PVC plate, and ingredients of the water-permeable porous foamed PVC plate include, in parts by weight, 85 parts of PVC resin with a weight average molecular weight of 120000 Da, 20 parts of CPVC, 15 parts of r-PVC, 8 parts of quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres, 8 parts of dynamic cross-linking elastomer, 12 parts of composite chemical foaming agent, 1 part of water-based physical foaming agent, 5 parts of organotin carboxylate composite stabilizer, 14 parts of trioctyl trimellitate, 9 parts of tributyl citrate, 7 parts of epoxy fatty acid methyl ester, 9 parts of processing aid and 0.3 parts of nano-silver antibacterial agent.

[0070] The CPVC has a chlorine content of 68%, a weight average molecular weight of 130000 Da, the r-PVC has an impurity content of less than or equal to 0.5%, a weight average molecular weight of 90000 Da and a residual chloroethylene monomer content of less than or equal to 0.5%. The composite chemical foaming agent is compounded by azodicarbonamide and 4,4'-oxobisbenzenesulfonylhydrazide at a mass ratio of 1:1.5, and the water-based physical foaming agent is compounded by sodium bicarbonate and citric acid at a molar ratio of 1:1.5.

[0071] The organotin carboxylate composite stabilizer is one of methyl tin carboxylate or octyl tin carboxylate; the processing aid is compounded by acrylic ester processing aid and composite lubricant at a mass ratio of 2:1, the composite lubricant is compounded by oxidized polyethylene wax and calcium stearate at a mass ratio of 1:1; the nano-silver antibacterial agent has a particle size of 20-50 nm and an effective silver content of greater than or equal to 99.0%.

[0072] The quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres are prepared from the following ingredients, in parts by weight: 100 parts of diatomite, 25 parts of perfluorohexyl ethyl acrylate, 10 parts of vinyl trimethoxysilane, 5 parts of methacryloyloxyethyl trimethyl ammonium chloride, 1.5 parts of di-tert-butyl peroxide and 600 parts of anhydrous ethanol.

[0073] The preparation method of the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres comprises the following steps:

[0074] 1) Diatomite was added into anhydrous ethanol, and ultrasonic dispersion was carried out at 70℃, a frequency of 40 kHz, and an ultrasonic power of 200 W for 90 min, during which stirring was carried out at a speed of 350 r / min for 2 min every 25 min to obtain a uniform suspension;

[0075] 2) Full-hexyl ethyl acrylate, vinyl trimethoxysilane, methacryloyloxyethyl trimethyl ammonium chloride, and di-tert-butyl peroxide were sequentially added into the suspension, nitrogen gas with a purity of ≥99.99% was introduced at a flow rate of 150 mL / min for 35 min, and then the temperature was raised to 85℃ under nitrogen protection, and constant stirring was carried out at a speed of 300 r / min for 6 h;

[0076] 3) After the reaction solution was cooled to room temperature, centrifugal separation was carried out at a speed of 4500 r / min for 20 min, the obtained solid was washed with anhydrous ethanol for 3 times, each time using an amount of 2.5 times the volume of the solid, and then the washed solid was dried under vacuum at 90℃ and a pressure of -0.09~-0.095 MPa for 12 h to a constant weight, and then the dried solid was crushed by an air-flow crusher and sieved through a 260-mesh standard sieve to obtain the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres.

[0077] The raw materials of the dynamic crosslinking elastomer include, in parts by weight, polyvinylidene fluoride-hexafluoropropylene copolymer particles 64, bio-based polycaprolactone particles 24, 2,2'-dithiodibenzoic acid 15, zinc acrylate 10, dicumyl peroxide 0.3, and dimethylbenzene 300; the weight average molecular weight of the polyvinylidene fluoride-hexafluoropropylene copolymer particles is 150000 Da, and the content of hexafluoropropylene is 15%; the number average molecular weight of the bio-based polycaprolactone particles is 20000 Da, and the bio-based carbon content is ≥95%.

[0078] The preparation method of the dynamic crosslinking elastomer includes the following steps:

[0079] (1) Diatomite was added into anhydrous ethanol, and ultrasonic dispersion was carried out at 70℃, a frequency of 40 kHz, and an ultrasonic power of 200 W for 90 min, during which stirring was carried out at a speed of 350 r / min for 2 min every 25 min to obtain a uniform suspension;

[0080] (2) Full-hexyl ethyl acrylate, vinyl trimethoxysilane, methacryloyloxyethyl trimethyl ammonium chloride, and di-tert-butyl peroxide were sequentially added into the suspension, nitrogen gas with a purity of ≥99.99% was introduced at a flow rate of 150 mL / min for 35 min, and then the temperature was raised to 85℃ under nitrogen protection, and constant stirring was carried out at a speed of 300 r / min for 6 h;

[0081] (3) cooling the reaction solution obtained in (2) to below 60℃, pouring the reaction solution into methanol at a volume ratio of reaction solution to methanol of 1:12, stirring at a speed of 800 r / min for 30 min, collecting the product by filtration, washing the product with methanol 3 times, each time using an amount of 3.5 times the volume of the solid, and then drying the product under vacuum at 80℃ and -0.09~-0.095 MPa to constant weight for 36 h, and obtaining the dynamic crosslinking elastomer after crushing.

[0082] The embodiment also discloses a production method of the water-permeable porous foamed PVC plate, comprising the following steps:

[0083] S1, raw material pretreatment and pre-homogenization:

[0084] S11, crushing r-PVC and passing through a 90-mesh sieve, and then drying the r-PVC, PVC resin and CPVC together in a hot air circulating oven at 90℃ for 4 h, and controlling the water content of the material to be less than or equal to 0.1%;

[0085] S12, weighing the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres and the nano-silver antibacterial agent, and premixing at a speed of 1200 r / min for 8 min;

[0086] S13, adding the material obtained in S11, the premixed material obtained in S12 and the remaining material into a high-speed thermal mixer, mixing at a speed of 1000 r / min for 6 min, and then mixing at a speed of 1500 r / min at 120℃ for 15 min, and cooling to a material temperature of less than or equal to 40℃;

[0087] S2, blending and synergistic foaming:

[0088] adding the mixture obtained in S13 into a co-rotating parallel twin-screw extruder, adjusting the temperature settings of each section of the extruder to be: zone 1 140℃, zone 2 155℃, zone 3 165℃, zone 4 170℃, and the die head 175℃, and the screw rotation speed is 300 r / min; after pressure stabilization by a melt pump, the foaming melt obtained in S2 is transferred to a single-screw extruder, supercritical carbon dioxide is pressurized to 16 MPa and heated to 42℃, and then injected into the middle of the single-screw extruder at a rate of 2.0 phr, and homogenized by a static mixer and a melt;

[0089] S3, molding:

[0090] extruding the foaming melt obtained in S2 from a wide flat plate die, the die lip opening is 2.5 times the thickness of the finished product, and then introducing into a three-roll calender, the calender roll temperatures are respectively 85℃ for the first roll, 65℃ for the second roll, and 45℃ for the third roll, and the roll gap pressure is 8 MPa; the calendered plate is cooled to less than or equal to 40℃ by a multi-section cooling roller group, drawn at a uniform speed of 2.5 m / min by a traction machine, and cut to a fixed length to obtain the finished product.

[0091] The embodiment also discloses an application of the water-permeable porous foamed PVC plate in a highway roadbed drainage belt.

[0092] Embodiment 3

[0093] The embodiment discloses a water-permeable porous foamed PVC plate, and ingredients of the water-permeable porous foamed PVC plate include, in parts by weight, 77 parts of PVC resin with a weight average molecular weight of 100000 Da, 15 parts of CPVC, 12 parts of r-PVC, 5 parts of quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres, 5 parts of dynamic cross-linking elastomer, 8 parts of composite chemical foaming agent, 0.5 parts of water-based physical foaming agent, 4 parts of organotin carboxylate composite stabilizer, 9 parts of trioctyl trimellitate, 7 parts of tributyl citrate, 6 parts of epoxy fatty acid methyl ester, 6 parts of processing aid and 0.2 parts of nano-silver antibacterial agent.

[0094] The CPVC has a chlorine content of 65%, a weight average molecular weight of 110000 Da, an impurity content of the r-PVC is less than or equal to 0.5%, a weight average molecular weight of 75000 Da, and a residual amount of chloroethylene monomer of less than or equal to 0.5%. The composite chemical foaming agent is compounded by azodicarbonamide and 4,4'-oxobisbenzenesulfonyl hydrazide at a mass ratio of 1:1.3, and the water-based physical foaming agent is compounded by sodium bicarbonate and citric acid at a molar ratio of 1:1.3.

[0095] The organotin carboxylate composite stabilizer is one of methyl tin carboxylate or octyl tin carboxylate; the processing aid is compounded by acrylic ester processing aid and composite lubricant at a mass ratio of 2:1, the composite lubricant is compounded by oxidized polyethylene wax and calcium stearate at a mass ratio of 1:1; the nano-silver antibacterial agent has a particle size of 20-50 nm and an effective silver content of greater than or equal to 99.0%.

[0096] Ingredients of the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres include, in parts by weight, 95 parts of diatomite, 20 parts of perfluorohexyl ethyl acrylate, 7 parts of vinyl trimethoxysilane, 4 parts of methacryloyloxyethyl trimethylammonium chloride, 1 part of di-tert-butyl peroxide and 500 parts of anhydrous ethanol.

[0097] The preparation method of the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres includes the following steps:

[0098] 1) The diatomite is added into anhydrous ethanol, and is ultrasonically dispersed at 65°C, a frequency of 30 kHz and an ultrasonic power of 175 W for 75 min, and is stirred at a rotating speed of 300 r / min for 1.5 min every 20 min during the ultrasonic dispersion, to obtain a uniform suspension;

[0099] 2) adding perfluorohexyl ethyl acrylate, vinyl trimethoxysilane, methacryloyloxyethyl trimethyl ammonium chloride and di-tert-butyl peroxide into the suspension in sequence, bubbling nitrogen gas with purity ≥ 99.99% at a flow rate of 125 mL / min for 30 min, and then heating to 80°C under nitrogen protection, and stirring at 250 r / min for 5 h;

[0100] 3) after cooling the reaction solution to room temperature, centrifugal separation is performed at a rotation speed of 3500 r / min for 17 min, the obtained solid is washed with anhydrous ethanol for 3 times, each time using 2 times the volume of the solid, and then the washed solid is dried under vacuum conditions of 85°C and -0.09~-0.095 MPa for 10 h to constant weight, and then crushed by an air flow crusher and sieved through a 250 mesh standard sieve to obtain the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres.

[0101] The raw materials of the dynamic crosslinking elastomer include, in terms of weight parts, polyvinylidene fluoride-hexafluoropropylene copolymer particles 60 parts, bio-based polycaprolactone particles 20 parts, 2,2'-dithiodibenzoic acid 12 parts, zinc acrylate 7 parts, diisopropylbenzene peroxide 0.2 parts, and dimethylbenzene 250 parts. The weight average molecular weight of the polyvinylidene fluoride-hexafluoropropylene copolymer particles is 125000 Da, and the content of hexafluoropropylene is 12%. The number average molecular weight of the bio-based polycaprolactone particles is 15000 Da, and the bio-based carbon content is ≥ 95%.

[0102] The preparation method of the dynamic crosslinking elastomer includes the following steps:

[0103] (1) adding dimethylbenzene in a reaction kettle, heating to 125°C, and adding polyvinylidene fluoride-hexafluoropropylene copolymer particles and bio-based polycaprolactone particles, and stirring at a rotation speed of 250 r / min for 2.5 h under nitrogen protection to completely dissolve the materials;

[0104] (2) adding 2,2'-dithiodibenzoic acid, zinc acrylate and diisopropylbenzene peroxide in sequence to the solution obtained in (1), and stirring at a rotation speed of 275 r / min at 130°C for 4 h;

[0105] (3) cooling the reaction solution obtained in (2) to below 60°C, pouring the reaction solution into methanol at a volume ratio of 1:10, stirring at a rotation speed of 650 r / min for 25 min, filtering and collecting the product, washing the product with methanol for 3 times, each time using 3 times the volume of the solid, and then drying the product under vacuum conditions of 75°C and -0.09~-0.095 MPa for 30 h to constant weight, and crushing to obtain the dynamic crosslinking elastomer.

[0106] The embodiment also discloses a production method of the water-permeable porous foamed PVC plate, which includes the following steps:

[0107] S1, raw material pretreatment and pre-homogenization:

[0108] S11, after the r-PVC is crushed, it is passed through a 85 mesh sieve, and then dried at 88°C in a hot air circulating oven for 3.5h, controlling the water content of the material to be ≤0.1%; the PVC resin and CPVC are added;

[0109] S12, the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres and the nano-silver antibacterial agent are weighed and premixed at a speed of 1100r / min for 7min;

[0110] S13, the material obtained by pretreatment in S11, the premixed material obtained in S12 and the remaining material are added to a high-speed thermal mixer, mixed at a speed of 900r / min for 5min, and then mixed at a speed of 1350r / min for 12min at 115°C, and cooled to a material temperature ≤40°C;

[0111] S2, blending and synergistic foaming:

[0112] The mixture obtained in S13 is added to a co-rotating parallel twin-screw extruder, and the temperature settings of each section of the extruder are adjusted to: zone 1 135°C, zone 2 150°C, zone 3 160°C, zone 4 165°C, and the die head 170°C, and the screw speed is 250r / min; after pressure stabilization by the melt pump, it is transferred to a single-screw extruder, supercritical carbon dioxide is pressurized to 13MPa and heated to 40°C, then injected into the middle of the single-screw extruder at a rate of 1.5phr, and homogenized by a static mixer and a melt;

[0113] S3, molding:

[0114] The foaming melt obtained in S2 is extruded from a wide flat plate die, the die lip opening is 2 times the thickness of the finished product, then introduced into a three-roll calender, the calender roll temperatures are respectively 80°C for the first roll, 60°C for the second roll, and 40°C for the third roll, and the roll gap pressure is 7MPa; the calendered plate is cooled to ≤40°C by a multi-section cooling roller group, drawn at a uniform speed of 2m / min by a traction machine, and then cut to a fixed length to obtain the finished product.

[0115] The embodiment also discloses an application of the water-permeable porous foamed PVC plate in an industrial floor moisture-proof cushion layer.

[0116] Comparative Example 1:

[0117] A water-permeable porous foamed PVC plate, a production method and an application thereof, the difference between the water-permeable porous foamed PVC plate and the embodiment 3 is only that the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres are not added, and the rest of the components and the process are unchanged.

[0118] Comparative Example 2:

[0119] A water-permeable porous foamed PVC plate, a production method and application thereof, the difference between which and example 3 is only that no dynamic cross-linking type elastomer is added, and the rest of the components and process remain unchanged.

[0120] Comparative example 3:

[0121] A water-permeable porous foamed PVC plate, a production method and application thereof, the difference between which and example 3 is only that no CPVC is added, and an equal weight of PVC resin is used instead, and the rest of the components and process remain unchanged.

[0122] Comparative example 4:

[0123] A water-permeable porous foamed PVC plate, a production method and application thereof, the difference between which and example 3 is only that the foaming agent only contains azodicarbonamide (the amount of which is equal to the total amount of the composite chemical foaming agent and the water-based physical foaming agent in example 3), no 4,4'-oxobenzene sulfonyl hydrazine and water-based physical foaming agent is added, and the amount of supercritical carbon dioxide injected is still 1.5 phr, and the rest of the components and process remain unchanged.

[0124] Comparative example 5:

[0125] A water-permeable porous foamed PVC plate, a production method and application thereof, the difference between which and example 3 is only that the water-based physical foaming agent is replaced by an equal amount of composite chemical foaming agent, and the amount of supercritical carbon dioxide injected is still 1.5 phr, and the rest of the components and process remain unchanged.

[0126] Comparative example 6:

[0127] A water-permeable porous foamed PVC plate, a production method and application thereof, the difference between which and example 3 is only that no acrylic ester processing aid (ACR) is added, and the rest of the components and process remain unchanged.

[0128] Comparative example 7:

[0129] A water-permeable porous foamed PVC plate, a production method and application thereof, the difference between which and example 3 is only that an equal weight of ordinary nitrile rubber powder (weight average molecular weight of 80000-100000 Da) is used instead of the dynamic cross-linking type elastomer, and the rest of the components and process remain unchanged.

[0130] Comparative example 8:

[0131] A water-permeable porous foamed PVC plate, a production method and application thereof, the difference between which and example 3 is only that an equal weight of ordinary 800 mesh silica powder is used instead of the quaternary ammonium salt grafted silica-fluorine hybrid porous microspheres, and the rest of the components and process remain unchanged.

[0132] Comparative example 9:

[0133] A water-permeable porous foamed PVC plate, a production method and application thereof, the difference between which and Example 3 is only that r-PVC is not added, and an equivalent amount of PVC resin is replaced, and the remaining components and processes remain unchanged.

[0134] Comparative Example 10:

[0135] A water-permeable porous foamed PVC plate, a production method and application thereof, the difference between which and Example 3 is only that bio-based composite plasticizer (i.e., without tributyl citrate and epoxy fatty acid methyl ester) is replaced with an equal weight of trioctyl trimellitate, and the remaining components and processes remain unchanged.

[0136] The water permeability coefficient, compressive strength, volume water absorption, apparent density, elongation at break, falling ball impact toughness, water permeability durability, antibacterial rate, moss resistance, and VOC emission of the PVC plates obtained in Examples 1-3 and Comparative Examples 1-10 above are detected, and the performance detection methods and standards are as follows:

[0137] 1. Water permeability coefficient

[0138] According to GB / T 25993-2010 “Water Permeable Pavement Brick and Water Permeable Pavement Panel”, Φ100mm×original thickness samples are prepared, the samples are placed in a water permeability instrument, a constant water head of 150mm is maintained, and the amount of water permeated through the sample is measured within 30 minutes at room temperature 23±2℃. According to the formula k=(Q×L) / (A×t×H), wherein Q is the water permeation amount (mL), L is the sample thickness (mm), A is the sample area (cm 2 ), t is the time (s), and H is the water head difference (mm), 3 parallel samples are tested, and the average value is taken, and the result is rounded to 1 decimal place.

[0139] 2. Compressive strength (10% deformation)

[0140] According to GB / T 8813-2008 “Hard Foamed Plastics-Determination of Compressive Properties”, 50mm×50mm×original thickness samples are prepared, and the compression test is carried out at a compression rate of 2mm / min in an environment of room temperature 23±2℃ and relative humidity 50±5%, the compression stress when the sample is compressed by 10% is recorded, 5 parallel samples are tested, the average value is taken, and the result is rounded to 1 decimal place.

[0141] 3. Volume water absorption

[0142] According to GB / T 8810-2005 "Determination of water absorption of rigid foamed plastics", prepare 100mmx100mmxoriginal thickness of the sample, immerse in distilled water at room temperature 23±2℃, water surface higher than the upper surface of the sample 25mm, after 24±1h, take out and dry the surface water with filter paper, immediately weigh. According to the formula W=(m2-m1) / (VxP)x100%, wherein m1 is the initial mass of the sample (g), m2 is the mass after soaking (g), V is the volume of the sample (cm 3 ), P is the density of distilled water (g / cm 3 ), test 3 parallel samples, take the average value, the result is retained to 1 decimal place.

[0143] 4. Apparent density

[0144] According to GB / T 6343-2009 "Determination of apparent density of foamed plastics and rubbers", prepare 100mmx100mmxoriginal thickness of the sample, weigh the sample mass with electronic balance (accuracy 0.01g), measure the sample size with vernier caliper (accuracy 0.01mm) and calculate the volume, according to the formula P=m / V, wherein m is the mass of the sample (g), V is the volume of the sample (cm 3 ), test 3 parallel samples, take the average value, the result is retained to integer.

[0145] 5. Elongation at break

[0146] According to GB / T 1040.3-2006 "Determination of tensile properties of plastics", cut type V dumbbell-shaped sample, test to break at room temperature 23±2℃, relative humidity 50±5%, with a tensile rate of 50mm / min, record the elongation by extensometer, according to the formula E=(L-L0) / L0x100%, wherein L is the gauge length at break (mm), L0 is the initial gauge length (mm), test 5 parallel samples, take the average value, the result is retained to integer.

[0147] 6. Ball impact toughness

[0148] According to QB / T 2858-2007 "Plastic film and sheet-ball impact test method", prepare 100mmx100mmxoriginal thickness of the sample, impact the center of the sample with a 500g steel ball from a height of 1m, test at room temperature 23±2℃, observe whether the sample cracks or perforates, measure the surface pit depth with depth ruler (accuracy 0.01mm), test 5 times, take the average pit depth, the result is retained to 1 decimal place, the smaller the depth, the better the toughness.

[0149] 7. Water permeability durability (anti-clogging cycle)

[0150] Self-made circulation test device (including liquid storage tank, peristaltic pump, sample fixing frame, reflux pipe; the volume of the liquid storage tank is 5 L, the flow rate of the peristaltic pump is adjustable in the range of 0-2 L / min, the sample fixing frame can seal and fix a Φ100 mm sample, and ensure that the mud water passes through the sample in one direction and then returns to the liquid storage tank), fix a Φ100 mm sample, circulate the mud water containing 5wt% fine silt (particle size ≤0.15 mm, silt particle size distribution: 0.075-0.15 mm accounts for 60%, ≤0.075 mm accounts for 40%) through the sample at a flow rate of 0.5 L / min, after each circulation for 30 minutes, reverse flush with 2 L / min flow rate of clean water for 2 minutes, then test according to the water permeability coefficient detection method, record the circulation number when the water permeability coefficient decreases to 50% of the initial value, test 3 parallel samples and take the average value.

[0151] 8. Antibacterial rate

[0152] According to GB / T 31402-2015 "Plastics - Test methods for antibacterial property", prepare a sample of 50mm×50mm×3mm, select Escherichia coli and Staphylococcus aureus as test strains, inoculation amount is 1×10 6 CFU / mL, cultivate at 37±1℃, relative humidity above 90% for 24 hours, calculate the antibacterial rate according to the formula R=(A-B) / A×100%, wherein A is the number of colonies (CFU / mL) of the blank sample, B is the number of colonies (CFU / mL) of the antibacterial sample, test 3 parallel samples, take the average value, and the result is retained to 1 decimal place.

[0153] 9. Anti-moss property

[0154] Test method: prepare a sample of 100mm×100mm×original thickness, place it in an artificial climate chamber, control the temperature at 25±2℃, relative humidity at 85±5%, and light intensity at 3000lux (light cycle 12h / 12h), spray nutrient solution (nutrient solution is 1 / 2 MS medium (containing sucrose 30g / L, agar 7g / L, pH 5.8)) containing moss spores (concentration 1×10 4 individual / mL) on the surface of the sample, observe once every 5 days, and measure the percentage of moss growth area on the surface of the sample after 30 days ("moss growth area is obtained by analyzing the photographed image of the sample surface by ImageJ software"), test 3 parallel samples, take the average value, and the result is retained to 1 decimal place.

[0155] 10. VOC emission

[0156] According to GB / T 34682-2017 "Plastics - Determination of volatile organic compounds in films and sheets", place a sample of 1m 2 2 in a 1m 3Inside the climate chamber, the temperature was controlled at 23±0.5℃ and the relative humidity at 50±5%. After maintaining the temperature for 24 hours, the VOC concentration inside the chamber was detected by gas chromatography-mass spectrometry. The test was performed three times, and the average value was taken. The result was retained to two decimal places.

[0157] The results are shown in Table 1.

[0158] Table 1 Performance parameters of PVC boards obtained in Examples 1-3 and Comparative Examples 1-10

[0159]

[0160] Using Example 3 as the control group, the performance differences and causes of Comparative Examples 1-10 are analyzed as follows:

[0161] Comparative Example 1 (Quaternary ammonium salt-free grafted silicon-fluorine hybrid porous microspheres)

[0162] The permeability coefficient decreased from 7.3 mm / s to 0.9 mm / s, a reduction of 87.7%; the apparent density decreased from 235 kg / m³. 3 Increased to 320 kg / m 3 The permeability increased by 36.2%; water permeability durability decreased from 165 cycles to 55 cycles, a decrease of 66.7%; antibacterial rate decreased from 99.6% to 82.5%, a decrease of 17.2%; and the area resistant to moss growth increased from 1.8% to 28.6%, an increase of 1488.9%. The reason is that without quaternary ammonium salt-grafted silicon-fluorine hybrid porous microspheres, there is no rigid porous framework to provide pre-placed permeable channels. During foaming, the nucleation of pores is disordered and the connectivity is extremely poor, making it impossible to form an effective permeable network. At the same time, the absence of quaternary ammonium salt antibacterial groups significantly degrades the antibacterial and anti-moss functions, leaving only a portion of the antibacterial effect of nano-silver.

[0163] Comparative Example 2 (Elastomer without dynamic cross-linking)

[0164] The compressive strength decreased from 4.2 MPa to 1.7 MPa, a drop of 59.5%; the elongation at break decreased from 96% to 32%, a drop of 66.7%; the depth of the drop ball impact dent increased from 1.1 mm to 4.9 mm, an increase of 345.5%; and the volumetric water absorption rate increased from 3.1% to 11.2%, an increase of 261.3%. The reasons are: the lack of a dynamic cross-linking network in the dynamically cross-linked elastomer; insufficient melt strength during the foaming stage; and the tendency for cells to merge and collapse, resulting in a loose structure and extremely low strength in the finished product. Weakened interfacial bonding significantly reduced toughness, and the lack of hydrophobic fluorine segments in the pore walls increased hydrophilicity, leading to a surge in water absorption.

[0165] Comparative Example 3 (without CPVC)

[0166] The water permeability coefficient decreased from 7.3 mm / s to 4.1 mm / s, a decrease of 43.8%; the compressive strength decreased from 4.2 MPa to 2.3 MPa, a decrease of 45.2%; the volume water absorption increased from 3.1% to 8.6%, an increase of 177.4%. The reason is that the polar pivot effect of CPVC is missing, the compatibility of r-PVC with quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres and dynamic cross-linking elastomer decreases, the uniformity of component dispersion decreases, the synergistic foaming and rigid-flexible synergistic effect is weakened, resulting in the overall deterioration of water permeability, strength and water resistance.

[0167] Comparative Example 4 (single chemical foaming agent - azodicarbonamide)

[0168] The water permeability coefficient decreased from 7.3 mm / s to 2.3 mm / s, a decrease of 68.5%; the apparent density increased from 235 kg / m 3 to 325 kg / m 3 , an increase of 38.3%; the water permeability durability decreased from 165 times to 78 times, a decrease of 52.7%. The reason is that the continuous gas production at medium temperature of 4,4'-oxybisbenzenesulfonyl hydrazide and the pre-gas production at low temperature of water-based foaming agent are missing, and only azodicarbonamide produces gas at high temperature, which cannot form multi-level pores, the cell density is low and the connectivity is poor, and the water permeability and anti-blocking performance are significantly reduced.

[0169] Comparative Example 5 (no water-based physical foaming agent)

[0170] The water permeability coefficient decreased from 7.3 mm / s to 3.1 mm / s, a decrease of 57.5%; the apparent density increased from 235 kg / m 3 to 305 kg / m 3 , an increase of 29.8%. The reason is that the pre-gas production effect of water-based foaming agent at low temperature is missing, the number of initial microbubbles is insufficient, and only chemical foaming and supercritical foaming are synergistic, the cell density and connectivity are not as good as the three-level synergistic system, and the water permeability performance is significantly deteriorated.

[0171] Comparative Example 6 (no ACR)

[0172] The water permeability coefficient decreased from 7.3 mm / s to 5.1 mm / s, a decrease of 30.1%; the elongation at break decreased from 96% to 71%, a decrease of 26.0%. The reason is that the auxiliary improvement effect of ACR on melt strength is missing, the synergistic stable cell effect of ACR with dynamic cross-linking elastomer is weakened, and the cell structure regularity decreases, resulting in small deterioration of water permeability and toughness.

[0173] Comparative Example 7 (ordinary nitrile rubber instead of dynamic cross-linking elastomer)

[0174] The compressive strength decreased from 4.2 MPa to 2.1 MPa, a decrease of 50.0%; the elongation at break decreased from 96% to 57%, a decrease of 40.6%; the volume water absorption increased from 3.1% to 9.6%, an increase of 209.7%. The reason is that the ordinary nitrile rubber has no dynamic crosslinking structure, which cannot improve the melt strength in the foaming stage, and cannot form an elastic network to enhance toughness, and has no hydrophobic fluorine segment, resulting in deterioration of strength, toughness and water resistance.

[0175] Comparative Example 8 (ordinary silicon powder instead of quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres)

[0176] The permeable coefficient decreased from 7.3 mm / s to 1.6 mm / s, a decrease of 78.1%; the elongation at break decreased from 96% to 52%, a decrease of 45.8%; the antibacterial rate decreased from 99.6% to 83.2%, a decrease of 16.5%; the moss growth area increased from 1.8% to 25.3%, an increase of 1294.4%. The reason is that the ordinary silicon powder has no porous structure and quaternary ammonium salt group, which cannot provide water permeable channels and antibacterial function, and can only play a small amount of physical filling role, resulting in a significant deterioration of water permeability, antibacterial and toughness performance.

[0177] Comparative Example 9 (without r-PVC)

[0178] The performance is close to that of Example 3, only the permeable coefficient decreases slightly from 7.3 mm / s to 7.1 mm / s, a decrease of 2.7%, which proves that r-PVC can effectively reduce the raw material cost without affecting the core performance, and the compatibility of the pretreated r-PVC with the matrix, quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres and dynamic crosslinking elastomer is good.

[0179] Comparative Example 10 (without bio-based plasticizer)

[0180] The VOC emission increased from 0.28 mg / m 3 to 0.85 mg / m 3 , an increase of 203.6%, and the remaining performance is close to that of Example 3, the reason is that the tributyl citrate (bio-based) and epoxy fatty acid methyl ester in the bio-based composite plasticizer have low volatility and low migration characteristics, and after being replaced by single trioctyl trimellitate, the volatilization rate of small molecule plasticizer is accelerated, resulting in a significant increase in VOC emission, which proves that the bio-based composite plasticizer can effectively improve the environmental friendliness of the material.

[0181] In summary, the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres are the core of constructing water permeable channels and antibacterial function, the porous structure guides the bubble connection, and the quaternary ammonium salt group realizes long-acting antibacterial and moss resistance. The dynamic crosslinking elastomer improves the melt strength and toughness through the dynamic crosslinking network, and guarantees the structure stability under high porosity. CPVC as a compatible hub guarantees the uniform dispersion of each component; the composite foaming system cooperates to form multi-level pores; the bio-based composite plasticizer reduces environmental load; ACR and composite lubricant ensure smooth processing. The synergistic effect of each component makes the material have the characteristics of high water permeability, high strength, high toughness, long-acting antibacterial and environmental friendly, and the core performance is significantly improved compared with the traditional scheme.

[0182] The above examples are only used to illustrate the technical solutions of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that they can modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A water permeable, porous, foamed PVC slab, characterized in that, By weight, its constituent raw materials include: 90-120 parts of matrix resin, 3-8 parts of quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres, 3-8 parts of dynamic cross-linked elastomer, 4.3-13.0 parts of foaming agent, 17-35 parts of composite stabilizing plasticizer, 3-9 parts of processing aid, and 0.1-0.3 parts of antibacterial agent.

2. The water permeable foamed PVC panel according to claim 1, characterized in that, Based on the total weight parts of the components: The matrix resin includes 70-85 parts of PVC resin, 10-20 parts of CPVC, and 10-15 parts of recycled polyvinyl chloride; The foaming agent includes 4-12 parts of a composite chemical foaming agent and 0.3-1.0 parts of a water-based physical foaming agent; wherein, the composite chemical foaming agent is composed of azodicarbonamide and 4,4'-oxobisbenzenesulfonyl hydrazine in a mass ratio of 1:(1.2-1.5), and the water-based physical foaming agent is composed of sodium bicarbonate and citric acid in a molar ratio of 1:(1.2-1.5).

3. The water permeable foamed PVC panel according to claim 2, characterized in that, The weight-average molecular weight of PVC resin is 80,000-120,000 Da; the chlorine content of CPVC is 63%-68%, and its weight-average molecular weight is 90,000-130,000 Da; the impurity content of recycled polyvinyl chloride is ≤0.5%, the weight-average molecular weight is 60,000-90,000 Da, and the residual amount of vinyl chloride monomer is ≤0.5%.

4. The water permeable foamed PVC panel according to claim 1, characterized in that, Based on the total weight parts of the components: The raw materials of the composite stabilizer plasticizer include: 2-5 parts of organotin carboxylate composite stabilizer, 5-14 parts of trioctyl trimellitate, 5-9 parts of tributyl citrate, and 5-7 parts of epoxy fatty acid methyl ester. The organotin carboxylate composite stabilizer is one of methyltin carboxylate or octyltin carboxylate. The processing aid is a compound of acrylate processing aid and composite lubricant in a mass ratio of 2:

1. The composite lubricant is a compound of oxidized polyethylene wax and calcium stearate in a mass ratio of 1:

1. The antibacterial agent is a nano-silver antibacterial agent with a particle size of 20-50nm and an effective silver content of ≥99.0%.

5. The water permeable foamed PVC panel according to claim 1, characterized in that, The raw materials for the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres, by weight, include: 90-100 parts of diatomaceous earth, 15-25 parts of perfluorohexyl ethyl acrylate, 5-10 parts of vinyltrimethoxysilane, 3-5 parts of methacryloyloxyethyltrimethylammonium chloride, 0.5-1.5 parts of di-tert-butyl peroxide, and 400-600 parts of anhydrous ethanol.

6. The water permeable foamed PVC panel according to claim 5, characterized in that The preparation method of quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres includes the following steps: 1) Add diatomaceous earth to anhydrous ethanol and ultrasonically disperse it for 60-90 minutes at 60-70℃, 20-40kHz frequency and 150-200W ultrasonic power to obtain a uniform suspension. 2) Add perfluorohexyl ethyl acrylate, vinyltrimethoxysilane, methacryloyloxyethyltrimethylammonium chloride and di-tert-butyl peroxide sequentially to the suspension, purge with nitrogen gas at a flow rate of 100-150 mL / min, bubble for 25-35 min, then raise the temperature to 75-85℃ under nitrogen protection and stir at a constant temperature of 200-300 r / min for 4-6 h. 3) After the reaction solution is cooled to room temperature, centrifugal separation is performed at a rotation speed of 2500-4500 r / min for 15-20 min, the obtained solid is washed with anhydrous ethanol for 3 times, then the washed solid is dried under vacuum conditions of 80-90 DEG C and -0.09~-0.095 MPa for 8-12 h until the weight is constant, the dried product is crushed by an air flow crusher and then passed through a 240-260 mesh standard sieve to obtain the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres.

7. The water permeable foamed PVC panel according to claim 1, characterized in that, The raw materials of the dynamic crosslinking elastomer include, in parts by weight, polyvinylidene fluoride-hexafluoropropylene copolymer particles 56-64 parts, bio-based polycaprolactone particles 16-24 parts, 2,2'-dithiodibenzoic acid 10-15 parts, zinc acrylate 5-10 parts, dicumyl peroxide 0.1-0.3 parts, dimethylbenzene 200-300 parts.

8. The water permeable foamed PVC panel according to claim 7, characterized in that The preparation method of the dynamic crosslinking elastomer includes the following steps: (1) adding dimethylbenzene in a reaction kettle, heating to 120-130 DEG C, adding polyvinylidene fluoride-hexafluoropropylene copolymer particles and bio-based polycaprolactone particles, stirring at a rotation speed of 200-300 r / min under nitrogen protection for 2-3 h to make the materials completely dissolved; (2) adding 2,2'-dithiodibenzoic acid, zinc acrylate and dicumyl peroxide in the solution obtained in (1) in sequence, stirring at a rotation speed of 250-300 r / min at 125-135 DEG C for 3-5 h; (3) cooling the reaction solution obtained in (2) to below 60 DEG C, pouring into methanol at a volume ratio of 1:(8-12), stirring at a rotation speed of 500-800 r / min for 20-30 min, filtering to collect the product, washing with methanol for 3 times, then drying the product under vacuum conditions of 70-80 DEG C and -0.09~-0.095 MPa for 24-36 h until the weight is constant, crushing to obtain the dynamic crosslinking elastomer.

9. A method of producing a water permeable porous foamed PVC slab according to any one of claims 1-8, characterized in that, including the following steps: S1, raw material pretreatment and pre-homogenization: S11, crushing the recovered polyvinyl chloride and passing through an 80-90 mesh sieve, then drying the crushed polyvinyl chloride together with PVC resin and CPVC in a hot air circulating oven at 85-90 DEG C for 3-4 h; S12, weighing the quaternary ammonium salt grafted silicon-fluorine hybrid porous microspheres and the nano-silver antibacterial agent, and pre-mixing at a rotation speed of 1000-1200 r / min for 5-8 min; S13, adding the material obtained in S11, the pre-mixed material obtained in S12 and the remaining material into a high-speed thermal mixer, first mixing at a rotation speed of 800-1000 r / min for 4-6 min, then mixing at a rotation speed of 1200-1500 r / min at 110-120 DEG C for 10-15 min, and cooling to a material temperature of ≤40 DEG C; S2, blending and synergistic foaming: The mixture obtained in S13 is added into a co-rotating parallel twin-screw extruder, and the temperature settings of each section of the extruder are adjusted to be: Zone 1 130-140 DEG C, Zone 2 145-155 DEG C, Zone 3 155-165 DEG C, Zone 4 160-170 DEG C, and the die head 165-175 DEG C, and the screw rotation speed is 200-300 r / min; after pressure stabilization by a melt pump, the mixture is transferred to a single-screw extruder, supercritical carbon dioxide is pressurized to 10-16 MPa and heated to 38-42 DEG C, and then injected into the middle part of the single-screw extruder at a rate of 1.0-2.0 phr, and then homogenized by a static mixer; S3, molding: The foamed melt obtained in S2 is extruded from a wide flat plate die, the die lip opening is 1.5-2.5 times the thickness of the finished product, and then introduced into a three-roll calender, the calender roll temperatures are respectively: the first roll 75-85 DEG C, the second roll 55-65 DEG C, and the third roll 35-45 DEG C, and the roll gap pressure is 5-8 MPa; the calendered plate is cooled to ≤40 DEG C by a multi-section cooling roller group, and then pulled by a traction machine at a uniform speed of 1.5-2.5 m / min, and then cut to a fixed length to obtain the finished product.

10. Application of the water-permeable porous foamed PVC plate according to any one of claims 1-8 in a sponge city water-permeable pavement, a highway roadbed drainage belt, an ecological slope protection drainage filter layer, an industrial floor moisture-proof cushion layer, and a sports ground foundation drainage layer.

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