CN112840915B

CN112840915B - Coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dissipation greenhouse film and preparation method thereof

Info

Publication number: CN112840915B
Application number: CN202110191462.6A
Authority: CN
Inventors: 刘继明; 庄新; 米庆华; 段玲
Original assignee: Shandong New Tianhe Plastic Co ltd
Current assignee: Shandong Baifeng Plastic Industry Co ltd
Priority date: 2021-02-19
Filing date: 2021-02-19
Publication date: 2022-04-15
Anticipated expiration: 2041-02-19
Also published as: CN112840915A

Abstract

The invention belongs to the technical field of agricultural film preparation, and particularly relates to a coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dissipation greenhouse film and a preparation method thereof. The greenhouse film comprises an inner layer, a middle layer, an outer layer and a coating layer; the inner layer is a dustproof aging-resistant layer, and the raw materials comprise polyethylene, dustproof master batch and aging-resistant master batch; the middle layer is a high-heat-insulation barrier layer, and the raw materials comprise polyethylene, an anti-aging master batch and a barrier heat-insulation master batch; the outer layer is a light-adjusting and light-converting layer, and the raw materials comprise polyethylene, light-converting master batch and anti-aging master batch; the coating layer is a long-acting dripping fog-eliminating layer. The coating type light-adjusting dustproof high-heat-preservation long-acting dripping fog-dissipation greenhouse film has the advantages that the light transmittance is more than 90%, the fog degree is less than 16%, the ratio of the internal light intensity to the external light intensity of a greenhouse is more than 75%, the photosynthetic efficiency is improved by light wave optimization by more than 30%, the duration of the dripping fog-dissipation dustproof function is more than 5 years, the film is synchronous with the service life of the greenhouse film, and the film can completely meet the requirements of farmers on various performance indexes of the greenhouse film in the three-to five-year service life.

Description

Coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dissipation greenhouse film and preparation method thereof

Technical Field

The invention belongs to the technical field of agricultural film preparation, and particularly relates to a coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dissipation greenhouse film and a preparation method thereof.

Background

Currently, the output and consumption of polyolefin agricultural greenhouse films are in the forefront of the world in China, and the market development speed of multifunctional high-end agricultural greenhouse films is increasing by two digits every year. There are two main types of compositions of functional greenhouse films, which are greenhouse covering materials currently on the market.

One method is to add light conversion agent, dust-proof agent, heat-insulating agent and various surfactants into the film to prepare the light conversion dust-proof high heat-insulating flowing drop fog-eliminating greenhouse film, and the flowing drop fog-eliminating function is achieved by gradual deposition of the surfactants in the film, the flowing drop lasting period of the internal addition type greenhouse film is only 4-6 months generally, and the requirement of modern high-efficiency agricultural development cannot be met.

The other method is to mix inorganic sol with a small amount of organic glue solution to prepare coating solution, and soak the polyolefin substrate subjected to corona treatment in the coating solution to form an inorganic coating layer on the inner surface of the membrane. The method has the advantages that the inorganic coating does not run off along with water, and the lasting period of dripping and fog dissipation can be synchronous with the service life of the film. However, the film has lagged behind the prior art in realizing the comprehensive function synergy of dust prevention, light modulation and conversion and high heat preservation in the long-term and long-life greenhouse film. The dustproof function and the light conversion function of the shed film in the market can not coexist in a synergistic manner, and the dustproof function, the light conversion function, the high heat preservation function and the dripping and fog dissipation function are only one or two.

Patent 2018115586536 discloses a five-layer co-extrusion greenhouse film with high dust-proof, long-acting and light conversion and a preparation method thereof, wherein the greenhouse film comprises an outer layer, a secondary outer layer, a middle layer, a secondary inner layer and an inner layer, the outer layer and the secondary outer layer are drip layers of the greenhouse film, the middle layer is a heat-insulating layer of the greenhouse film, and the inner layer and the secondary inner layer are long-life layers of the greenhouse film; wherein, add the masterbatch that changes the light in inferior inlayer, add dustproof masterbatch in the inlayer. The production process described in the above patent is of an internal addition type, and the light-conversion dustproof high-heat-preservation flowing drop fog-dissipation greenhouse film is prepared by adding a light conversion agent, a dustproof agent, a heat preservation agent and various surfactants into the film, and the flowing drop fog-dissipation function is achieved by gradual precipitation of the surfactants in the film, so that the flowing drop duration of the internal addition type greenhouse film is only 4-6 months generally, and the requirement of modern high-efficiency agricultural development cannot be met. For the greenhouse film, the drip fog dispersal performance has long lasting period and synchronous service life of the film, and has the functions of high light transmission, high heat preservation, dust prevention and accurate dimming and light conversion, and is a main index for evaluating the quality and performance of a greenhouse film product.

In order to solve the problems in the prior art, the development of a greenhouse film with comprehensive functions is urgently needed. Under the promotion of quality agriculture and green agriculture, the high-end functional greenhouse film market has great potential. The invention relates to a high-end comprehensive functional greenhouse film, which realizes the functions of super long-life pesticide resistance, accurate light modulation and light conversion, high heat preservation, self-cleaning, dust prevention, long-acting dripping and fog dissipation, and is the subject of research by the invention.

Disclosure of Invention

The purpose of the invention is: provides a coating type light-adjusting dustproof high-heat-preservation long-acting dripping fog-dispersing greenhouse film. The greenhouse film has the comprehensive functions of dust prevention, light modulation and light conversion, high heat preservation, long-acting dripping fog dissipation period and synchronous service life of the film.

The coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dissipation greenhouse film comprises an inner layer, a middle layer, an outer layer and a coating layer; the inner layer is a dustproof aging-resistant layer, and the raw materials comprise polyethylene, dustproof master batch and aging-resistant master batch; the middle layer is a high-heat-insulation barrier layer, and the raw materials comprise polyethylene, an anti-aging master batch and a barrier heat-insulation master batch; the outer layer is a light-adjusting and light-converting layer, and the raw materials comprise polyethylene, light-converting master batch and anti-aging master batch; the coating layer is a long-acting dripping fog-eliminating layer.

Wherein:

the polyethylene in the inner layer raw material is at least one of Low Density Polyethylene (LDPE), Linear Low Density Polyethylene (LLDPE) or metallocene linear low density polyethylene (mLLDPE).

The dustproof master batch in the inner layer raw material is at least one of fluorine-containing type, maleic anhydride grafting type or amide type.

The anti-aging master batch in the inner layer raw material is a hindered amine light stabilizer and antioxidant composite anti-aging master batch.

Preferably, the raw material composition of the inner layer is as follows: 20 to 25 percent of Low Density Polyethylene (LDPE), 20 to 25 percent of Linear Low Density Polyethylene (LLDPE), 30 to 47 percent of metallocene linear low density polyethylene (mLLDPE), 4.5 to 10 percent of ageing-resistant master batch and 8 to 12 percent of dustproof master batch.

The polyethylene in the middle layer raw material is at least one of Low Density Polyethylene (LDPE), Linear Low Density Polyethylene (LLDPE) or metallocene linear low density polyethylene (mLLDPE).

The insulating master batch in the middle layer raw material is any one of hydrotalcite insulating master batch, kaolin insulating master batch or talcum powder insulating master batch, and preferably the hydrotalcite insulating master batch.

The anti-aging master batch in the middle layer raw material is a hindered amine light stabilizer and antioxidant composite anti-aging master batch.

Preferably, the raw material composition of the middle layer is as follows: 20 to 25 percent of Low Density Polyethylene (LDPE), 20 to 25 percent of Linear Low Density Polyethylene (LLDPE), 30 to 50 percent of metallocene linear low density polyethylene (mLLDPE), 4.5 to 10 percent of anti-aging master batch and 5 to 10.5 percent of barrier heat-preservation master batch.

The polyethylene in the raw material of the outer layer is at least one of Low Density Polyethylene (LDPE), Linear Low Density Polyethylene (LLDPE) or metallocene linear low density polyethylene (mLLDPE).

The anti-aging master batch in the outer layer raw material is a hindered amine light stabilizer and antioxidant composite anti-aging master batch.

The light conversion master batch in the outer layer raw material is any one or two of inorganic rare earth light conversion master batch or organic rare earth light conversion master batch.

Preferably, the raw material composition of the outer layer is as follows: 20-25% of Low Density Polyethylene (LDPE), 20-25% of Linear Low Density Polyethylene (LLDPE), 35-50% of metallocene linear low density polyethylene (mLLDPE), 5-10% of ageing-resistant master batch and 2-5% of light conversion master batch.

The coating layer is a coating liquid dry matter prepared from inorganic aluminum sol, silica sol and organic mixed glue solution.

The coating layer comprises the following raw materials: 6-8% of coating liquid stock solution and 92-90% of deionized water.

Preferably, the coating liquid is any one of TG-150 or TF-820G; wherein the TG-150 was manufactured by Nippon bamboo fat Co., Ltd, and the TF-820G was manufactured by Loran Green Source Ltd.

The density of the Low Density Polyethylene (LDPE) contained in the inner layer, the middle layer and the outer layer is 0.920-0.923g/cm³The Melt Index (MI) is from 0.2 to 1.0g/10min, preferably from 0.2 to 0.5g/10 min.

Preferably, the Low Density Polyethylene (LDPE) is any one of 2100TN00 produced by the petroleum of zilu, 2420D produced by the petroleum of daqing or LD165 imported.

The Linear Low Density Polyethylene (LLDPE) has a density of from 0.918 to 0.926g/cm³And a Melt Index (MI) of 0.8 to 1.0g/10 min.

Preferably, the Linear Low Density Polyethylene (LLDPE) is any one of 1001AV manufactured by Exxon Mobil, 9085 manufactured by Tianjin Union carbon, 0209AA manufactured by Shanghai Saiko, or 2045G brand manufactured by Dow chemical industry.

The metallocene linear low density polyethylene (m-LLDPE) has a density of from 0.916 to 0.920g/cm³And a Melt Index (MI) of 0.2 to 1.0g/10 min.

Preferably, the metallocene linear low density polyethylene is one or more of 1018MA, 2010MC, 2005MC, XP6056, XP6026 manufactured by Exxon Mobil corporation and D139 brand manufactured by Philips Cinfuron corporation.

The dustproof master batch comprises the following raw materials: 50-70% of Low Density Polyethylene (LDPE), 20-30% of Linear Low Density Polyethylene (LLDPE), 3-10% of fluoroelastomer, 4-7% of metal stearate soap and 1-3% of amides.

Wherein:

the Melt Index (MI) of the Low Density Polyethylene (LDPE) in the dust-repellent masterbatch is 2.0g/10min, preferably any of the designations 2102TN00 from Qilu petrochemical manufacture or 2426H from Daqing petrochemical manufacture.

The Linear Low Density Polyethylene (LLDPE) had a Melt Index (MI) of 2.0g/10min and a powder appearance.

Preferably, the Linear Low Density Polyethylene (LLDPE) is any of the ziegler petrochemical 7042 or the Tianjun 1820 grades.

The fluoroelastomer is any one of PPA2100 or PPA 5924.

The PPA2100 manufacturer is Shanghai Shandong polymer chemical industry, and the PPA5924 manufacturer is 3M company.

The metal stearate soap is one of calcium stearate and zinc stearate.

The amide is erucamide.

Calcium stearate, zinc stearate and erucamide are all commercially available chemical products.

Preferably, the dustproof master batch is a commercial product manufactured by Shanghai physical research company under the trade name EFT 995; the maleic anhydride grafted dustproof master batch is manufactured by Changchun applied chemistry research and has a mark number of 20-FC.

The anti-aging master batch comprises the following raw materials: 40 to 45 percent of Low Density Polyethylene (LDPE), 29.5 to 40 percent of Linear Low Density Polyolefin (LLDPE), 12 to 24 percent of light stabilizer, 3 to 4 percent of antioxidant and 0.5 to 1.8 percent of hydrotalcite acid acceptor.

Wherein: the Melt Index (MI) of the Low Density Polyethylene (LDPE) in the aging resistant masterbatch is 2.0g/10min, preferably any one of 2102TN00 produced by Qilu petrochemical industry or 2426H brand produced by Daqing petrochemical industry.

The light stabilizer is a hindered amine light stabilizer, preferably, the hindered amine light stabilizer is at least one of HALS944, HS-625, T-69 or UV-119.

HALS944 (944 for short), HS-625, T-69 are manufactured by Beijing Tiangang company; the UV-119 manufacturer is Sabo.

The antioxidant is a compound of hindered phenols and phosphites, preferably, the antioxidant is any one of B215 or B225; the manufacturers of B215 or B225 are all Yabao Jinhai, Zhejiang.

The hydrotalcite acid acceptor is any one of HTP or HTB; the manufacturer of the HTP is made by sakai chemical corporation; the manufacturer of HTB was Taian Boyan chemical company.

The light conversion master batch comprises the following raw materials: 50-60% of Low Density Polyethylene (LDPE), 32-38% of Linear Low Density Polyethylene (LLDPE) and 8-12% of light conversion agent.

The Melt Index (MI) of the low-density polyethylene (LDPE) in the light conversion master batch is 2.0g/10min, and the low-density polyethylene (LDPE) is preferably any one of the grades 2102TN00 or 2426H of Qilu petrochemical industry.

Preferably, the Linear Low Density Polyethylene (LLDPE) is any of the ziegler petrochemical production 7042 or the Tianjun chemical production 1820 grades.

The light conversion agent is preferably an inorganic rare earth light conversion agent, and the inorganic rare earth light conversion agent is any one or more of green-to-red GTR-650, purple-to-blue VTB-440, purple-to-red VTR660 or red-to-blue dual-light RBI6545, which are all manufactured by Hunan Severe technologies.

According to the requirement of crops on light quality, one or more light conversion agents are selected to convert ultraviolet light and green light which are difficult to absorb by the crops into an optimal growth action spectrum with high crop absorption rate, so that the converted red light and blue light are radiated into the greenhouse as much as possible to adjust and improve the illumination environment in the greenhouse and improve the photosynthetic efficiency of the crops.

The principle of the preferred light conversion agents is: the excitation spectrum of the light conversion agent is matched with the spectrum of sunlight on the ground, and the emission spectrum is matched with the absorption spectrum of chlorophyll.

Preferably, the insulation master batch comprises the following raw materials: 20-30% of Low Density Polyethylene (LDPE), 10-20% of Linear Low Density Polyethylene (LLDPE) and 50-70% of hydrotalcite heat preservation agent.

Wherein:

the Melt Index (MI) of Low Density Polyethylene (LDPE) in the barrier heat-insulating master batch is 2.0g/10min, and the Low Density Polyethylene (LDPE) is preferably selected from any one of the grades 2102TN00 of Qilu petrochemical industry or 2426H of Daqing petrochemical industry.

The hydrotalcite heat retaining agent is preferably made by Sakai chemical company under the trade name HTP.

The preparation method of the various masterbatches comprises the following steps:

the preparation method of the dustproof master batch comprises the following steps: 50-70% of low-density polyethylene (LDPE), 20-30% of linear low-density polyethylene (LLDPE), 3-10% of fluoroelastomer, 4-7% of stearic acid soap and 1-3% of amide are proportionally added into an internal mixer for kneading and plasticizing, then fed into a single-screw extrusion granulator through an open mill, and subjected to hot granulation and air cooling drying to prepare dustproof master batch for later use.

Wherein: the temperature of the internal mixer is 125-140 ℃, the plasticizing time is 15-20 minutes, and the temperature of the single-screw extrusion granulator is 140-160 ℃.

The preparation method of the anti-aging master batch comprises the following steps: 40 to 45 percent of Low Density Polyethylene (LDPE), 29.5 to 40 percent of Linear Low Density Polyethylene (LLDPE), 12 to 24 percent of light stabilizer, 3 to 4 percent of antioxidant and 0.5 to 1.8 percent of hydrotalcite acid acceptor; adding the mixture into an internal mixer according to a certain proportion, kneading and plasticizing, feeding the mixture into a single-screw extrusion granulator through an open mill, carrying out hot granulation, and carrying out air cooling drying to obtain the anti-aging master batch for later use.

The preparation method of the light conversion master batch comprises the following steps: 50 to 60 percent of Low Density Polyethylene (LDPE), 32 to 38 percent of Linear Low Density Polyethylene (LLDPE) and 8 to 12 percent of light conversion agent; adding the mixture into an internal mixer according to a certain proportion, kneading and plasticizing, feeding the mixture into a single-screw extrusion granulator through an open mill, carrying out hot granulation, and carrying out air cooling drying to obtain the light conversion master batch for later use.

The preparation method of the blocking heat-insulation master batch comprises the following steps: 20 to 30 percent of Low Density Polyethylene (LDPE), 10 to 20 percent of Linear Low Density Polyethylene (LLDPE) and 50 to 70 percent of hydrotalcite heat preservation agent; adding the materials into an internal mixer according to a certain proportion, kneading and plasticizing, feeding the materials into a single-screw extrusion granulator through an open mill, carrying out hot granulation, and carrying out air cooling drying to obtain the barrier heat-insulation master batch for later use.

The coating type light-adjusting dustproof high-heat-preservation long-acting dripping fog-dispersal greenhouse film has the thickness ratio of the inner layer to the middle layer to the outer layer of 0.8-1.2:1.2-0.8:1, and the dry matter content of the dried coating liquid of the coating layer is more than 0.20g/m²。

The coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dissipation shed film disclosed by the invention has the advantages that through formula adjustment and according to a layered additional function, dustproof master batch and anti-aging master batch are respectively added into the inner layer, and the inner layer faces the outside of the shed after buckling the shed, so that the effects of self-cleaning, dust prevention, light resistance, thermal oxidative degradation and aging resistance can be realized; the middle layer is added with a heat insulation master batch and an anti-aging master batch, which mainly have the functions of blocking the radiation of far infrared rays to the outside of the greenhouse at night, reducing the heat conductivity coefficient of the greenhouse film to achieve the effect of heat insulation at night, and simultaneously have the performances of resisting light, thermal oxidation degradation and aging resistance; the outer layer is added with light conversion master batch and aging-resistant master batch, which mainly has the main functions of selecting one or more light conversion agents according to the light quality requirement of crops, converting ultraviolet light and green light which are difficult to be absorbed by the crops into the optimal growth action spectrum with high crop absorption rate, and enabling the converted red light and blue light to be radiated into the greenhouse as much as possible to adjust and improve the illumination environment in the greenhouse, improve the photosynthesis efficiency of the crops and enable the fruits and vegetables to increase the yield and have good precocity quality; the outer layer has the effects of resisting light, thermal oxidation degradation and aging. The coating layer is a long-acting dripping fog-eliminating layer, and mainly has the functions of eliminating fog in the greenhouse for a long time, improving light transmittance, facilitating photosynthesis of crops and reducing crop diseases and insect pests.

The preparation method of the coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dissipation shed film comprises the steps of uniformly mixing and stirring the components of the inner layer, the middle layer and the outer layer, adding the mixture into a three-layer co-extrusion extruder, and obtaining the coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dissipation shed film through melt plasticizing blow molding, traction, cooling and shaping, corona, coating liquid impregnation, drying, edge welding, seam cutting and folding.

Wherein: in the three-layer co-extrusion unit, the temperatures of the inner layer, the middle layer and the outer layer are all 170-215 ℃, the temperature of a die head is 190-235 ℃, the temperature of an oven is 85-102 ℃, and the blow-up ratio is 1.5-2.5.

The coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dissipation greenhouse film is used for preparing agricultural covering materials.

Compared with patent 2018115586536, the invention is a coating liquid prepared by mixing inorganic sol with a small amount of organic glue solution, and polyolefin substrate processed by corona treatment is dipped in the coating liquid to form an inorganic coating layer on the inner surface of the film. The method has the advantages that the inorganic coating does not run off along with water, the lasting period of dripping and fog dissipation can be synchronous with the service life of the film, simultaneously, the anti-aging master batch is added into each layer of the film, and the light conversion master batch, the dustproof master batch and the blocking heat preservation master batch are added in layers, so that the super-long service life, accurate light modulation and light conversion, high heat preservation, self-cleaning and dustproof performance, and the long-acting dripping and fog dissipation function are synchronous with the service life of the film are realized.

Compared with the diffuse scattering polyethylene greenhouse film disclosed in the patent 2017113848794 and the preparation method thereof, the production process disclosed in the patent 2017113848794 is an internal addition type, and the layering functions of the product are completely different from those of the invention. The haze is more than 50%, the production process of the product is a coating type, high-light-transmission and low-haze greenhouse film, the haze is less than 20%, and the two films have large functional difference and no comparability.

Compared with the prior art, the invention has the following beneficial effects:

(1) the coating type light-dimming dust-proof high-heat-preservation long-acting dripping fog-dissipation shed film has the comprehensive functions of dust prevention, light-dimming light conversion, high heat preservation, long-acting dripping fog dissipation period and synchronous service life of the film, and the service life is 3-5 years.

(2) The coating type light-adjusting dustproof high-heat-preservation long-acting dripping fog-dissipation greenhouse film has the advantages that the width of the film is more than 10M, the thickness is 0.10-0.18mm, the light transmittance is more than 90%, the haze is less than 16%, the light intensity ratio of the inside and the outside of a greenhouse is more than 75%, the photosynthetic efficiency is improved by light wave optimization by more than 30%, the duration of the dripping fog-dissipation dustproof function is more than 5 years, the film is synchronous with the service life of the greenhouse film, and the requirements of farmers on various performance indexes of the greenhouse film in a five-year service life can be completely met.

(3) The coating type light-adjusting dust-proof high-heat-preservation long-acting dripping fog dispersal greenhouse film has strong weather resistance, good dust prevention and heat preservation performance, has the function of adjusting and converting transmitted light waves, can accurately convert partial ultraviolet light and green light wave bands in sunlight into red, blue light and far-red light wave bands which are favored by the growth of crops by adding a light conversion agent into the greenhouse film according to the requirements of the crops on light quality, realizes the accurate optimization of the illumination environment of the crops, has an excellent dripping fog dispersal function, can eliminate fog in a greenhouse, is beneficial to the photosynthesis of the crops, reduces the plant diseases and insect pests of the crops, can enable fruits and vegetables to be premature, increase the yield and have good quality, and is suitable for covering and cultivating various crops.

(4) The preparation method of the coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dissipation greenhouse film is scientific and reasonable, stable and reliable in quality and simple and easy to operate.

Drawings

FIG. 1 is an enlarged schematic view of the cross-sectional structure of a coating-type light-dimming dust-proof high-heat-preservation long-acting dripping fog-dispersal shed film.

Detailed Description

The present invention is further described below with reference to examples.

Example 1

The coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dispersal greenhouse film described in the embodiment 1 comprises an inner layer, a middle layer, an outer layer and a coating layer; the inner layer is a dustproof aging-resistant layer, and the raw materials comprise polyethylene, dustproof master batch and aging-resistant master batch; the middle layer is a high-heat-insulation barrier layer, and the raw materials comprise polyethylene, an anti-aging master batch and a barrier heat-insulation master batch; the outer layer is a light-adjusting and light-converting layer, and the raw materials comprise polyethylene, light-converting master batch and anti-aging master batch; the coating layer is a long-acting dripping fog-eliminating layer.

The inner layer comprises the following raw materials: 21.3 percent of Low Density Polyethylene (LDPE), 21.3 percent of Linear Low Density Polyethylene (LLDPE), 42.6 percent of metallocene linear low density polyethylene (mLLDPE), 5.0 percent of ageing-resistant master batch and 9.8 percent of dustproof master batch.

The inner layer comprises the following raw materials in parts by weight: 25 parts of low-density polyethylene (LDPE), 25 parts of linear low-density polyethylene (LLDPE), 50 parts of metallocene linear low-density polyethylene, 5.9 parts of anti-aging master batch and 11.5 parts of dustproof master batch.

The Melt Index (MI) of Low Density Polyethylene (LDPE) is 0.2-0.3g/10min, No. 2420D, Daqing petrochemical manufacturing, 25 parts; linear Low Density Polyethylene (LLDPE) has a Melt Index (MI) of 0.8-1.0g/10min, a designation of 9085, manufactured by Tianjin carbon-Linked, 25 parts.

Metallocene linear low density polyethylene (m-LLDPE) having a Melt Index (MI) of 1.0g/10min, No. 2010MC, manufactured by Exxon Mobil, 50 parts; 5.9 parts of an anti-aging master batch; the dustproof master batch is manufactured by Shanghai research company with the trademark of EFT995, and 11.5 parts.

The aging-resistant master batch comprises: 40% of low-density polyethylene (LDPE), 30.5% of powdery linear low-density polyolefin (LLDPE), 24% of light stabilizer, 4% of antioxidant and 1.5% of hydrotalcite acid acceptor.

The anti-aging master batch comprises the following raw materials in parts by weight: 40 parts of low-density polyethylene (LDPE), 30.5 parts of powdery linear low-density polyolefin (LLDPE), 24 parts of light stabilizer, 4 parts of antioxidant and 1.5 parts of hydrotalcite acid acceptor.

Low Density Polyethylene (LDPE) designation 2102TN00, manufactured by zelworm petrochemical, 40 parts.

30.5 portions of powdered low-density linear polyethylene (LLDPE) with the trade name of 7042 made by Qilu petrochemical industry.

The light stabilizer is available under the trade name HALS944, manufactured by Beijing Tiangang company, 24 parts.

The anti-oxidant is B215, 4 parts by Yabao company of Jinhai, Zhejiang.

The hydrotalcite acid acceptor is made under the trademark HTP by sakai chemical corporation, 1.5 parts.

The preparation method of the anti-aging master batch comprises the following steps: low Density Polyethylene (LDPE)2102TN00, 40 parts; 7042 parts of linear low-density polyolefin (LLDPE); light stabilizer HALS944, 24 parts; 4 parts of antioxidant B215; 1.5 parts of hydrotalcite acid acceptor HTP. Accurately weighing, adding the mixture into an internal mixer for kneading and plasticizing, feeding the mixture into a single-screw extrusion granulator through an open mill, carrying out hot granulation, and carrying out air cooling drying to obtain the anti-aging master batch for later use. Wherein: the temperature of the internal mixer is 135-138 ℃, the plasticizing time is 18-20 minutes, and the temperature of each section is 140-160 ℃ (160 ℃ in the first section, 160 ℃ in the second section and 140 ℃ in the third section).

The middle layer is a high-heat-insulation barrier layer and comprises the following raw materials: 21.3 percent of low-density polyethylene (LDPE), 21.3 percent of linear low-density polyethylene (LLDPE), 42.6 percent of metallocene linear low-density polyethylene (mLLDPE), 5.0 percent of ageing-resistant master batch and 9.8 percent of barrier heat-preservation master batch.

The middle layer comprises the following raw materials in parts by weight: 25 parts of low-density polyethylene (LDPE), 25 parts of linear low-density polyethylene (LLDPE), 50 parts of metallocene linear low-density polyethylene, 5.9 parts of anti-aging master batch and 11.5 parts of barrier heat-insulating master batch.

The Melt Index (MI) of Low Density Polyethylene (LDPE) is 0.2-0.3g/10min, No. 2420D, Daqing petrochemical manufacturing, 25 parts; the Linear Low Density Polyethylene (LLDPE) has a Melt Index (MI) of 0.8-1.0g/10min, a mark number of 9085, manufactured by Tianjin carbon-linked method, of 25 parts; the metallocene linear low density polyethylene (m-LLDPE) has a Melt Index (MI) of 1.0g/10min under the designation 1018MA, manufactured by Exxon Mobil, of 50 parts; 5.9 parts of an anti-aging master batch; wherein the component content and the preparation method of the anti-aging master batch and the inner layer are not described; 11.5 parts of a heat insulation master batch.

The heat insulation blocking master batch comprises the following raw materials: 28% of low-density polyethylene (LDPE), 12% of linear low-density polyethylene (LLDPE) and 60% of hydrotalcite heat preservation agent.

The heat-insulation blocking master batch comprises the following raw materials in parts by weight: 28 parts of low-density polyethylene (LDPE), 12 parts of powdery linear low-density polyethylene (LLDPE) and 60 parts of hydrotalcite heat-insulating agent.

Low Density Polyethylene (LDPE) grade 2102TN00, manufactured by ziegler petrochemical, 28 parts; powdered Linear Low Density Polyethylene (LLDPE) grade 7042, manufactured by Qilu petrochemical, 12 parts; the hydrotalcite heat retaining agent was made by Sakai chemical corporation under the trademark HTP, 60 parts.

The preparation method of the blocking heat-insulation master batch comprises the following steps:

low Density Polyethylene (LDPE)2102TN00, 28 parts; 7042 parts of Linear Low Density Polyethylene (LLDPE); 60 parts of hydrotalcite heat preservation agent HTP. Accurately metering, adding the mixture into an internal mixer, kneading and plasticizing, feeding the mixture into a single-screw extrusion granulator through an open mill, carrying out hot granulation, and carrying out air-cooled drying to obtain the blocking and heat-insulating master batch for later use.

The internal mixer is 135-138 ℃, the plasticizing time is 18-20 minutes, and the temperature of each section is 140-160 ℃ (wherein the temperature of the first section is 160 ℃, the temperature of the second section is 160 ℃, and the temperature of the third section is 140 ℃).

The outer layer is a light-adjusting and light-converting layer and comprises the following raw materials: 23% of Low Density Polyethylene (LDPE), 23% of Linear Low Density Polyethylene (LLDPE), 46% of metallocene linear low density polyethylene (mLLDPE), 5.0% of ageing-resistant master batch and 3.0% of light conversion master batch.

The outer layer comprises the following raw materials in parts by weight: 25 parts of low-density polyethylene (LDPE), 25 parts of powdery linear low-density polyethylene (LLDPE), 50 parts of metallocene linear low-density polyethylene (mLLDPE), 5.4 parts of anti-aging master batch and 3.3 parts of light conversion master batch.

The Melt Index (MI) of Low Density Polyethylene (LDPE) is 0.2-0.3g/10min, No. 2420D, Daqing petrochemical manufacturing, 25 parts; the Linear Low Density Polyethylene (LLDPE) has a Melt Index (MI) of 0.8-1.0g/10min, a mark number of 9085, manufactured by Tianjin carbon-Linked, 25 parts.

The metallocene linear low density polyethylene (mLLDPE) has a Melt Index (MI) of 1.0g/10min, No. 2010MC, manufactured by Exxon Mobil, of 50 parts; 5.4 parts of an anti-aging master batch; the component content and the preparation method of the anti-aging master batch and the inner layer are not described; and 3.3 parts of light conversion master batch.

The light conversion master batch comprises the following raw materials: 54% of Low Density Polyethylene (LDPE), 36% of Linear Low Density Polyethylene (LLDPE) and 10% of light conversion agent.

The light conversion master batch comprises the following raw materials in parts by weight: 54 parts of low-density polyethylene (LDPE), 36 parts of linear low-density polyethylene (LLDPE) and 10 parts of light conversion agent.

The light conversion master batch comprises: low Density Polyethylene (LDPE)2102TN00, zilwu petrochemical, 54 parts; powdered Linear Low Density Polyethylene (LLDPE)7042, manufactured by ziegler petrochemical, 36 parts; the light conversion agent is green to red GTR-650, manufactured by Hunan Severe technologies, 10 parts.

The preparation method of the light conversion master batch comprises the following steps: mixing Low Density Polyethylene (LDPE)2102, TN00, 54 parts, powdered Linear Low Density Polyethylene (LLDPE)7042, 36 parts; 10 parts of light conversion agent GTR650 for converting green into red; accurately metering, adding into an internal mixer, kneading and plasticizing, feeding into a single-screw extrusion granulator through an open mill, carrying out hot granulation, and carrying out air cooling drying to obtain the light conversion master batch for later use.

The coating layer comprises the following raw materials: 8% of coating liquid stock solution and 92% of deionized water.

The coating liquid was rated TG-150, manufactured by Nippon bamboo grease Co.

Adding the weighed coating liquid stock solution into a stainless steel tank, adding deionized water in proportion, stirring uniformly, standing for 20 minutes, and pumping into a liquid hanging tank for later use, wherein the dry matter content of the coating layer is more than 0.2g/m²。

The preparation method of the coating type light-dimming dust-proof high-heat-preservation long-acting dripping fog-dispersal shed film described in the embodiment 1 comprises the following steps: the coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dissipation greenhouse film is prepared by respectively mixing and stirring the component materials and the master batch of the inner layer, the middle layer and the outer layer uniformly, adding the mixture into a three-layer co-extrusion extruder, and carrying out melt plasticizing blow molding, traction, cooling and shaping, corona, coating liquid impregnation, drying, edge welding, seam cutting, code spraying and folding.

The specification of the prepared product is 10000/0.12 mm; the layer thickness ratio of the inner layer to the middle layer to the outer layer is 1:1: 1; the blow-up ratio was 1.8. In the three-layer co-extrusion unit, the temperatures of the inner layer, the middle layer and the outer layer are all 170-215 ℃, and the temperatures of a machine neck and a die head are 190-235 ℃; the temperature of each zone of the oven is 85-102 ℃.

Table 1 example 1 process conditions

The coated light-dimming dust-proof high-heat-preservation long-acting dripping fog-dissipation greenhouse film prepared in the embodiment 1 has the light transmittance of 91.4%, the haze of 14.7% and the duration of dripping fog-dissipation dust-proof function of 5 years. Adding a light conversion agent GTR650 to ensure that the greenhouse film has the function of converting part of green light into red light which is more beneficial to the growth of plants, thereby improving the quality of crops, having good coloring and high yield; the dustproof master batch is added to ensure that the greenhouse film is bright as new after being washed by wind, blowing and rain, and the reduction of the light transmittance is not obvious. The greenhouse film prepared in the example 1 is already applied to the field of the agricultural test base of Tujiazhu and Gaozhuangshandong under Laiwu, the yield of the planted tomatoes is increased by 15-20%, the red fruits are ripe 7-9 days in advance, and the quality of the fruits is good. The greenhouse film prepared in the example 1 is determined to be a film special for tomatoes by expert evaluation.

Example 2

The coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dispersal greenhouse film described in the embodiment 2 comprises an inner layer, a middle layer, an outer layer and a coating layer; the inner layer is a dustproof aging-resistant layer, and the raw materials comprise polyethylene, dustproof master batch and aging-resistant master batch; the middle layer is a high-heat-insulation barrier layer, and the raw materials comprise polyethylene, an anti-aging master batch and a barrier heat-insulation master batch; the outer layer is a light-adjusting and light-converting layer, and the raw materials comprise polyethylene, light-converting master batch and anti-aging master batch; the coating layer is a long-acting dripping fog-eliminating layer.

The inner layer comprises the following raw materials: 21.3 percent of Low Density Polyethylene (LDPE), 21.3 percent of Linear Low Density Polyethylene (LLDPE), 42.5 percent of metallocene linear low density polyethylene (mLLDPE), 5.5 percent of ageing-resistant master batch and 9.4 percent of dustproof master batch.

The inner layer comprises the following raw materials in parts by weight: 25 parts of low-density polyethylene (LDPE), 25 parts of linear low-density polyethylene (LLDPE), 50 parts of metallocene linear low-density polyethylene, 6.5 parts of anti-aging master batch and 11 parts of dustproof master batch.

Metallocene linear low density polyethylene (mLLDPE) having a Melt Index (MI) of 1.0g/10min under the trademark 2010MC manufactured by Exxon Mobil, 50 parts; 6.5 parts of an anti-aging master batch; the dustproof master batch is 20FC, manufactured by research on Changchun applied chemistry and 11 parts.

Low Density Polyethylene (LDPE) designation 2102TN00, 40 parts by Qilu petrochemical manufacture.

The light stabilizer is made by 24 parts of HS-625, manufactured by Beijing Tiangang company.

The anti-oxidant is B215, 4 parts by Yabao company of Jinhai, Zhejiang.

The preparation method of the aging-resistant master batch is the same as that of example 1 and is not described again.

The middle layer is a high-heat-insulation barrier layer and comprises the following raw materials: 21.5% of low-density polyethylene (LDPE), 21.5% of linear low-density polyethylene (LLDPE), 42.9% of metallocene linear low-density polyethylene (mLLDPE), 4.7% of ageing-resistant master batch and 9.4% of barrier heat-insulating master batch.

The middle layer comprises the following raw materials in parts by weight: 25 parts of low-density polyethylene (LDPE), 25 parts of linear low-density polyethylene (LLDPE), 50 parts of metallocene linear low-density polyethylene, 5.5 parts of anti-aging master batch and 11 parts of barrier heat-insulating master batch.

The Melt Index (MI) of Low Density Polyethylene (LDPE) is 0.2-0.3g/10min, No. 2420D, Daqing petrochemical manufacturing, 25 parts; the Linear Low Density Polyethylene (LLDPE) has a Melt Index (MI) of 0.8-1.0g/10min, a mark number of 9085, manufactured by Tianjin carbon-linked method, of 25 parts; the metallocene linear low density polyethylene (m-LLDPE) has a Melt Index (MI) of 1.0g/10min under the designation 1018MA, manufactured by Exxon Mobil, of 50 parts; 5.5 parts of an anti-aging master batch; wherein the component content and the preparation method of the anti-aging master batch and the inner layer are not described; 11 parts of a heat insulation master batch.

The preparation method of the barrier heat-preservation master batch is the same as that of example 1 and is not described.

The light conversion master batch comprises: low Density Polyethylene (LDPE)2102TN00, zilwu petrochemical, 54 parts; powdered Linear Low Density Polyethylene (LLDPE)7042, manufactured by ziegler petrochemical, 36 parts; the light conversion agent is green-to-red GTR-650 and purple-to-blue VTB440 manufactured by Hunan Severe technologies, 10 parts, wherein GTR-650: 7 parts, VTB-440: and 3 parts.

The preparation method of the light conversion master batch is the same as that of example 1 and is not described again.

The coating liquid was rated TG-150, manufactured by Nippon bamboo grease Co.

The preparation method of the coating type light-dimming dust-proof high-heat-preservation long-acting dripping fog-dispersal shed film described in the embodiment 2 comprises the following steps: the coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dissipation greenhouse film is prepared by respectively mixing and stirring the component materials and the master batch of the inner layer, the middle layer and the outer layer uniformly, adding the mixture into a three-layer co-extrusion extruder, and carrying out melt plasticizing blow molding, traction, cooling and shaping, corona, coating liquid impregnation, drying, edge welding, seam cutting, code spraying and folding.

The specification of the prepared product is 10000/0.12 mm; the layer thickness ratio of the inner layer to the middle layer to the outer layer is 1:1: 1; the blow-up ratio was 1.8. In the three-layer co-extrusion unit, the temperatures of the inner layer, the middle layer and the outer layer are all 170-215 ℃, and the temperatures of a machine neck and a die head are 190-235 ℃; the oven temperature is 85-102 ℃. The specific process parameters are the same as in example 1, table 1.

The coated light-dimming dust-proof high-heat-preservation long-acting dripping fog-dissipation greenhouse film prepared in the embodiment 2 has the light transmittance of 90.6%, the haze of 13.9% and the duration of dripping fog-dissipation dust-proof function of 5 years. Adding light conversion agent green to red GTR-650 and purple to red VTB-440 to make the greenhouse film have the function of converting part of green light into red light beneficial to plant growth, and selectively converting the transmitted ultraviolet light into blue light easy to be absorbed by plant, so as to raise the photosynthetic efficiency, quality and yield of crops. The dustproof master batch is added to ensure that the greenhouse film is bright as new after being washed by wind, blowing and rain, and the reduction of the light transmittance is not obvious. In the embodiment 2, the application of the method in the field of agricultural large test bases of Manuka village and Gaozhuangshandong under Laiwu is demonstrated, the yield of planted sweet peppers is increased by 15-20%, the coloring rate of red fruits is high and the red fruits are ripe 7-9 days ahead, the quality of the fruits is good, the fruits are large, crisp and sweet, and the picking period is long. The film of the embodiment 2 is determined to be a special film for sweet pepper by expert evaluation.

Example 3

The coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dissipation greenhouse film described in the embodiment 3 comprises an inner layer, a middle layer, an outer layer and a coating layer; the inner layer is a dustproof aging-resistant layer, and the raw materials comprise polyethylene, dustproof master batch and aging-resistant master batch; the middle layer is a high-heat-insulation barrier layer, and the raw materials comprise polyethylene, an anti-aging master batch and a barrier heat-insulation master batch; the outer layer is a light-adjusting and light-converting layer, and the raw materials comprise polyethylene, light-converting master batch and anti-aging master batch; the coating layer is a long-acting dripping fog-eliminating layer.

The raw material composition and the proportion of the inner layer are the same as those of the example 1, and the only difference is that the grade of the hindered amine light stabilizer in the anti-aging master batch is different from that of the raw material in the dustproof master batch.

Metallocene linear low density polyethylene (m-LLDPE) having a Melt Index (MI) of 1.0g/10min, No. 2010MC, manufactured by Exxon Mobil, 50 parts; 5.9 parts of an anti-aging master batch; 11.5 portions of dustproof master batch.

The light stabilizer is made by 24 parts of T-69, manufactured by Beijing Tiangang company.

The anti-oxidant is B215, 4 parts by Yabao company of Jinhai, Zhejiang.

The dustproof master batch comprises the following raw materials: 60% of low-density polyethylene (LDPE), 29% of linear low-density polyethylene (LLDPE), 5% of fluoroelastomer, 4% of metal stearate soap and 2% of amides.

The dustproof master batch comprises the following raw materials in parts by weight: 60 parts of low-density polyethylene (LDPE), 29 parts of linear low-density polyethylene (LLDPE), 5 parts of fluoroelastomer, 2 parts of zinc stearate, 2 parts of calcium stearate and 2 parts of erucamide.

Wherein:

the Low Density Polyethylene (LDPE) has a Melt Index (MI) of 2.0g/10min, preferably 2102TN00, 60 parts for the production of Zilu petrochemical; the powdery low-density linear polyethylene (LLDPE) has the Melt Index (MI) of 2.0g/10min and the Qilu petrochemical product 7042 of 29 parts; 5 parts of a fluorine elastomer PPA2100, manufactured by Shanghai Lu polymerization chemical industry; 2 parts of zinc stearate, 2 parts of calcium stearate and the preparation of the longevity gold chemical industry; 2 parts of erucamide, manufactured by Qingdao chemical plants.

The preparation method of the dustproof master batch comprises the following steps: adding LDPE 2102TN00 of carrier resin, 60 parts of Qilu petrochemical engineering, 7042 powder LLDPE and 29 parts of Qilu petrochemical engineering into an internal mixer, and adding the fluorine elastomer PPA2100, 2 parts of Shanghai Lu polymerization chemical engineering, 2 parts of zinc stearate, 2 parts of calcium stearate and the chemical engineering of Shuguang Jinyu; 2 parts of erucamide, manufactured by Qingdao chemical plants. Stirring and kneading the mixture in an internal mixer, and granulating the mixture by a single-screw extruder for later use. The temperature of the internal mixer is 135 ℃, the plasticizing time is 16-18 minutes, and the temperature of each zone is 140-160 ℃ (wherein the temperature of the first zone is 160 ℃, the temperature of the second zone is 160 ℃, and the temperature of the third zone is 140 ℃).

The middle layer is a high-heat-insulation barrier layer and comprises the following raw materials: 21.2% of low-density polyethylene (LDPE), 21.2% of linear low-density polyethylene (LLDPE), 42.4% of metallocene linear low-density polyethylene (mLLDPE), 5.1% of ageing-resistant master batch and 10.1% of barrier heat-insulating master batch.

The middle layer comprises the following raw materials in parts by weight: 25 parts of low-density polyethylene (LDPE), 25 parts of linear low-density polyethylene (LLDPE), 50 parts of metallocene linear low-density polyethylene, 6 parts of anti-aging master batch and 12 parts of barrier heat-preservation master batch.

The Melt Index (MI) of Low Density Polyethylene (LDPE) is 0.2-0.3g/10min, No. 2420D, Daqing petrochemical manufacturing, 25 parts; the Linear Low Density Polyethylene (LLDPE) has a Melt Index (MI) of 0.8-1.0g/10min, a mark number of 9085, manufactured by Tianjin carbon-linked method, of 25 parts; the metallocene linear low density polyethylene (m-LLDPE) has a Melt Index (MI) of 1.0g/10min under the designation 1018MA, manufactured by Exxon Mobil, of 50 parts; 6 parts of an anti-aging master batch; wherein the component content and the preparation method of the anti-aging master batch and the inner layer are not described; and 12 parts of a barrier heat-insulation master batch.

The light conversion master batch comprises: low Density Polyethylene (LDPE)2102TN00, zilwu petrochemical, 54 parts; powdered Linear Low Density Polyethylene (LLDPE)7042, manufactured by ziegler petrochemical, 36 parts; the light conversion agent is purple to red VTR-660, manufactured by Hunan Severe technologies, 10 parts.

The coating liquid was rated TG-150, manufactured by Nippon bamboo grease Co.

The preparation method of the coating type light-dimming dust-proof high-heat-preservation long-acting dripping fog-dispersal shed film described in the embodiment 3 comprises the following steps: the coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dissipation greenhouse film is prepared by respectively mixing and stirring the component materials and the master batch of the inner layer, the middle layer and the outer layer uniformly, adding the mixture into a three-layer co-extrusion extruder, and carrying out melt plasticizing blow molding, traction, cooling and shaping, corona, coating liquid impregnation, drying, edge welding, seam cutting, code spraying and folding.

The coated light-dimming dust-proof high-heat-preservation long-acting dripping fog-dissipation greenhouse film prepared in the embodiment 3 has the light transmittance of 90.3%, the haze of 14.8% and the duration of dripping fog-dissipation dust-proof function of 5 years. The light conversion agent purple to red VTR-660 is added to ensure that the greenhouse film has the function of converting part of ultraviolet light into red light which is more beneficial to the growth of plants, thereby improving the growth, fruit coloring, quality and yield of crops. The dustproof master batch is added to ensure that the greenhouse film is bright as new after being washed by wind, blowing and rain, and the reduction of the light transmittance is not obvious. The embodiment is already applied to the field of the Zhenlujiazhuang Shandong agricultural great test base below Laiwu, the yield of the planted tomatoes is increased by 15-20%, the red fruit rate is high and is mature 7-9 days ahead, the fruit quality is good, and the red fruit rate is high and the picking period is long.

Example 4

The coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dissipation greenhouse film described in the embodiment 4 comprises an inner layer, a middle layer, an outer layer and a coating layer; the inner layer is a dustproof aging-resistant layer, and the raw materials comprise polyethylene, dustproof master batch and aging-resistant master batch; the middle layer is a high-heat-insulation barrier layer, and the raw materials comprise polyethylene, an anti-aging master batch and a barrier heat-insulation master batch; the outer layer is a light-adjusting and light-converting layer, and the raw materials comprise polyethylene, light-converting master batch and anti-aging master batch; the coating layer is a long-acting dripping fog-eliminating layer.

The inner layer comprises the following raw materials: 20.8% of low-density polyethylene (LDPE), 20.8% of linear low-density polyethylene (LLDPE), 41.7% of metallocene linear low-density polyethylene (mLLDPE), 7.5% of ageing-resistant master batch and 9.2% of dustproof master batch.

The inner layer comprises the following raw materials in parts by weight: 25 parts of low-density polyethylene (LDPE), 25 parts of linear low-density polyethylene (LLDPE), 50 parts of metallocene linear low-density polyethylene, 9 parts of anti-aging master batch and 11 parts of dustproof master batch.

Metallocene linear low density polyethylene (m-LLDPE) having a Melt Index (MI) of 1.0g/10min, No. 2010MC, manufactured by Exxon Mobil, 50 parts; 9 parts of an anti-aging master batch; the dustproof master batch is manufactured by Shanghai research company with the trademark of EFT995 and 11 parts.

The aging-resistant master batch comprises: 45% of low-density polyethylene (LDPE), 33.5% of powdery linear low-density polyolefin (LLDPE), 16% of light stabilizer, 4% of antioxidant and 1.5% of hydrotalcite acid acceptor.

The anti-aging master batch comprises the following raw materials in parts by weight: 45 parts of low-density polyethylene (LDPE), 33.5 parts of powdery linear low-density polyolefin (LLDPE), 16 parts of light stabilizer, 4 parts of antioxidant and 1.5 parts of hydrotalcite acid acceptor.

Low Density Polyethylene (LDPE) designation 2102TN00, manufactured by zelworm petrochemical, 45 parts.

Powdered low density linear polyethylene (LLDPE) designation 7042, manufactured by Qilu petrochemical, 33.5 parts.

The light stabilizer is made by 16 parts of Beijing Tiangang company with the brand number of T-69.

The anti-oxidant is B215, 4 parts by Yabao company of Jinhai, Zhejiang.

The middle layer is a high-heat-insulation barrier layer and comprises the following raw materials: 21.2% of low-density polyethylene (LDPE), 21.2% of linear low-density polyethylene (LLDPE), 42.4% of metallocene linear low-density polyethylene (mLLDPE), 6.8% of ageing-resistant master batch and 8.4% of barrier heat-insulating master batch.

The middle layer comprises the following raw materials in parts by weight: 25 parts of low-density polyethylene (LDPE), 25 parts of linear low-density polyethylene (LLDPE), 50 parts of metallocene linear low-density polyethylene, 8 parts of anti-aging master batch and 10 parts of barrier heat-insulating master batch.

The Melt Index (MI) of Low Density Polyethylene (LDPE) is 0.2-0.3g/10min, No. 2420D, Daqing petrochemical manufacturing, 25 parts; the Linear Low Density Polyethylene (LLDPE) has a Melt Index (MI) of 0.8-1.0g/10min, a mark number of 9085, manufactured by Tianjin carbon-linked method, of 25 parts; the metallocene linear low density polyethylene (m-LLDPE) has a Melt Index (MI) of 1.0g/10min under the designation 1018MA, manufactured by Exxon Mobil, of 50 parts; 8 parts of an anti-aging master batch; wherein the component content and the preparation method of the anti-aging master batch and the inner layer are not described; and 10 parts of a barrier heat-insulation master batch.

The outer layer is a light-adjusting and light-converting layer and comprises the following raw materials: 22.4% of low-density polyethylene (LDPE), 22.4% of linear low-density polyethylene (LLDPE), 44.9% of metallocene linear low-density polyethylene (mLLDPE), 7.2% of ageing-resistant master batch and 3.1% of light conversion master batch.

The outer layer comprises the following raw materials in parts by weight: 25 parts of low-density polyethylene (LDPE), 25 parts of powdery linear low-density polyethylene (LLDPE), 50 parts of metallocene linear low-density polyethylene (mLLDPE), 8 parts of ageing-resistant master batch and 3.5 parts of light conversion master batch.

The metallocene linear low density polyethylene (mLLDPE) has a Melt Index (MI) of 1.0g/10min, No. 2010MC, manufactured by Exxon Mobil, of 50 parts; 8 parts of an anti-aging master batch; the component content and the preparation method of the anti-aging master batch and the inner layer are not described; and 3.5 parts of light conversion master batch.

The light conversion master batch comprises: low Density Polyethylene (LDPE)2102TN00, zilwu petrochemical, 54 parts; powdered Linear Low Density Polyethylene (LLDPE)7042, manufactured by ziegler petrochemical, 36 parts; the light conversion agent is a double-light-conversion green-to-red and purple-to-blue compound brand number RBI6545 manufactured by Hunan Severe technologies, 10 parts.

The coating liquid was rated TG-150, manufactured by Nippon bamboo grease Co.

The preparation method of the coating type light-dimming dust-proof high-heat-preservation long-acting dripping fog-dispersal shed film described in the embodiment 4 comprises the following steps: the coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dissipation greenhouse film is prepared by respectively mixing and stirring the component materials and the master batch of the inner layer, the middle layer and the outer layer uniformly, adding the mixture into a three-layer co-extrusion extruder, and carrying out melt plasticizing blow molding, traction, cooling and shaping, corona, coating liquid impregnation, drying, edge welding, seam cutting, code spraying and folding.

The coated light-dimming dust-proof high-heat-preservation long-acting dripping fog-dissipation greenhouse film prepared in the embodiment 4 has the light transmittance of 90.2%, the haze of 15.5% and the duration of dripping fog-dissipation dust-proof function of 5 years. And a compound light conversion agent of green to red and purple to blue RBI6545 is added, so that the greenhouse film has the function of converting part of green light into red light which is more beneficial to plant growth, and selectively converts the transmitted ultraviolet light into blue light which is easy to absorb by plants, thereby improving the photosynthetic efficiency, quality and yield of crops. The dustproof master batch is added to ensure that the greenhouse film is bright as new after being washed by wind, blowing and rain, and the reduction of the light transmittance is not obvious. The greenhouse film prepared in the embodiment 4 is already applied to the field of the agricultural and big test base of the Odong Tujia and the Gaozhuang Shandong under Laiwu, the yield is increased by 15-20% by planting strawberries, the red fruit rate is high, the fruits are mature 7-9 days in advance, the fruit quality is good, and the strawberry picking period is prolonged by 10-15 days. The film is determined to be a special film for strawberries by expert evaluation.

Comparative example 1

The dustproof high-heat-preservation long-acting dripping fog-dispersal shed film in the comparative example 1 comprises an inner layer, a middle layer, an outer layer and a coating layer; the inner layer is a dustproof aging-resistant layer, and the raw materials comprise polyethylene, dustproof master batch and aging-resistant master batch; the middle layer is a high-heat-insulation barrier layer, and the raw materials comprise polyethylene, an anti-aging master batch and a barrier heat-insulation master batch; the outer layer is an ageing-resistant layer, and the raw materials comprise polyethylene and an ageing-resistant master batch; the coating layer is a long-acting dripping fog-eliminating layer.

The inner layer comprises the following raw materials: 21.2% of low-density polyethylene (LDPE), 21.2% of linear low-density polyethylene (LLDPE), 42.4% of metallocene linear low-density polyethylene (mLLDPE), 5.0% of ageing-resistant master batch and 10.2% of dustproof master batch.

The inner layer comprises the following raw materials in parts by weight: 25 parts of low-density polyethylene (LDPE), 25 parts of linear low-density polyethylene (LLDPE), 50 parts of metallocene linear low-density polyethylene, 6 parts of anti-aging master batch and 12 parts of dustproof master batch.

Metallocene linear low density polyethylene (m-LLDPE) having a Melt Index (MI) of 1.0g/10min, No. 2010MC, manufactured by Exxon Mobil, 50 parts; 6 parts of an anti-aging master batch; the dustproof master batch is manufactured by Shanghai research company with the trademark of EFT995 and 12 parts.

The anti-oxidant is B215, 4 parts by Yabao company of Jinhai, Zhejiang.

The preparation method of the anti-aging master batch is the same as that of example 1.

The middle layer is a high-heat-insulation barrier layer and comprises the following raw materials: 21.2% of low-density polyethylene (LDPE), 21.2% of linear low-density polyethylene (LLDPE), 42.4% of metallocene linear low-density polyethylene (mLLDPE), 5.0% of ageing-resistant master batch and 10.2% of barrier heat-insulating master batch.

The composition and preparation method of the blocking and heat-insulating master batch are the same as those of example 1.

The outer layer is an ageing-resistant layer and is prepared from the following raw materials: 23.7% of low-density polyethylene (LDPE), 23.7% of linear low-density polyethylene (LLDPE), 47.4% of metallocene linear low-density polyethylene (mLLDPE) and 5.2% of ageing-resistant master batch.

The outer layer comprises the following raw materials in parts by weight: 25 parts of low-density polyethylene (LDPE), 25 parts of powdery linear low-density polyethylene (LLDPE), 50 parts of metallocene linear low-density polyethylene (mLLDPE) and 5.5 parts of anti-aging master batch.

The metallocene linear low density polyethylene (mLLDPE) has a Melt Index (MI) of 1.0g/10min, No. 2010MC, manufactured by Exxon Mobil, of 50 parts; 5.5 parts of an anti-aging master batch; the component contents and the preparation method of the aging-resistant master batch and the inner layer are not described.

The coating liquid was rated TG-150, manufactured by Nippon bamboo grease Co.

The preparation method of the dustproof high-heat-preservation long-acting dripping fog-dispersal shed film in the comparative example 1 comprises the following steps: the material and the master batch of each component of the inner layer, the middle layer and the outer layer are respectively mixed and stirred uniformly, added into a three-layer co-extrusion extruder, and subjected to melt plasticizing blow molding, traction, cooling and shaping, corona, coating solution impregnation, drying, edge welding, seam cutting, code spraying and folding to obtain the dustproof high-heat-preservation long-acting dripping fog dispersal greenhouse film.

The specification of the prepared product is 10000/0.12 mm; the layer thickness ratio of the inner layer to the middle layer to the outer layer is 1:1: 1; the blow-up ratio was 1.8. In the three-layer co-extrusion unit, the temperatures of the inner layer, the middle layer and the outer layer are all 170-215 ℃, and the temperatures of a machine neck and a die head are 190-235 ℃; the oven temperature was 85-102 ℃ and the process parameters were as in Table 1 of example 1.

Except that the outer layer is not added with the light conversion master batch, other material components and the preparation method are the same as those of the embodiment 1, and the dustproof high-heat-preservation long-acting dripping fog dispersal shed film provided by the comparative example 1 does not have the light modulation and light conversion functions. The dust-proof effect, aging resistance, long-acting dripping and fog-dispersing performance are the same as those of the example 1, the field application demonstration of the agricultural large test base of the Zhenlu Jiazhuang and the Gaozhuang Shandong under Laiwu is already carried out in the present example, compared with the shed film making and shed splicing of the example 1, the coloring and mature period of the fruits is 5-7 days later, and the yield is reduced by 8% -10%.

Comparative example 2

The coating type high-heat-preservation long-acting dripping fog-dispersal shed film described in the comparative example 2 comprises an inner layer, a middle layer, an outer layer and a coating layer; the inner layer is an ageing-resistant layer, and the raw materials comprise polyethylene and an ageing-resistant master batch; the middle layer is a high-heat-insulation barrier layer, and the raw materials comprise polyethylene, an anti-aging master batch and a barrier heat-insulation master batch; the outer layer is an ageing-resistant layer, and the raw materials comprise polyethylene and an ageing-resistant master batch; the coating layer is a long-acting dripping fog-eliminating layer.

The inner layer comprises the following raw materials: 23.7 percent of low-density polyethylene (LDPE), 23.7 percent of linear low-density polyethylene (LLDPE), 47.4 percent of metallocene linear low-density polyethylene (mLLDPE) and 5.2 percent of ageing-resistant master batch.

The inner layer comprises the following raw materials in parts by weight: 25 parts of low-density polyethylene (LDPE), 25 parts of linear low-density polyethylene (LLDPE), 50 parts of metallocene linear low-density polyethylene and 5.5 parts of anti-aging master batch.

Metallocene linear low density polyethylene (mLLDPE) having a Melt Index (MI) of 1.0g/10min under the trademark 2010MC manufactured by Exxon Mobil, 50 parts; 5.5 parts of an anti-aging master batch.

The content and the preparation method of the components of the anti-aging master batch are completely the same as those of the example 2.

The contents of the components of the barrier heat-preservation master batch and the preparation method are the same as those of the example 2, and are not described again.

The metallocene linear low density polyethylene (mLLDPE) has a Melt Index (MI) of 1.0g/10min, No. 2010MC, manufactured by Exxon Mobil, of 50 parts; 5.5 parts of an anti-aging master batch.

The coating liquid was rated TG-150, manufactured by Nippon bamboo grease Co.

The preparation method of the coating type high-heat-preservation long-acting dripping fog-dispersal shed film in the comparative example 2 comprises the following steps: the coating type high-heat-preservation long-acting dripping fog-dissipation greenhouse film is prepared by respectively mixing and stirring the component materials and the master batch of the inner layer, the middle layer and the outer layer uniformly, adding the mixture into a three-layer co-extrusion extruder, and carrying out melt plasticizing blow molding, traction, cooling and shaping, corona, coating liquid impregnation, drying, edge welding, seam cutting, code spraying and folding.

The specification of the prepared product is as follows: 10000/0.12 mm; the layer thickness ratio is 1:1: 1; the blow-up ratio is 1.8; in the three-layer co-extrusion unit, the temperatures of the inner layer, the middle layer and the outer layer of the extruder are all 170-215 ℃, and the temperatures of a machine neck and a die head are 190-235 ℃; the oven temperature was 85-102 ℃ and the process parameters were as in Table 1 of example 1.

The coating type high-heat-preservation long-acting dripping fog dispersal shed film provided by the comparative example 2 has the same material components and preparation method except that the outer layer is not added with the light conversion master batch, and the inner layer is not added with the dustproof master batch, and does not have the functions of light modulation, light conversion and dust prevention. The dust-proof effect is poor, the light transmittance is greatly reduced, and the photosynthetic efficiency is reduced. The anti-aging and long-acting dripping fog-removing performance is the same as that of example 2, the comparative example 2 is already demonstrated in the field application of the great test base of the agricultural great test base of the Zhenlujiazhu and the Gaozhuangshandong under Laiwu, the planted sweet peppers are compared with the film of example 2 by shed splicing, the coloring and maturing period of the fruits is 7-9 days later, and the yield is reduced by 10% -12%.

Comparative example 3

The heat-insulating long-acting dripping fog-dispersal shed film of the comparative example 3 comprises an inner layer, a middle layer, an outer layer and a coating layer; the inner layer is an ageing-resistant layer, and the raw materials comprise polyethylene and an ageing-resistant master batch; the middle layer is a high heat insulation and aging resistant layer, and the raw materials comprise polyethylene, aging resistant master batch and insulation master batch; the outer layer is an ageing-resistant layer, and the raw materials comprise polyethylene and an ageing-resistant master batch; the coating layer is a long-acting dripping fog-eliminating layer.

The composition and preparation method of the anti-aging master batch are the same as those of example 1, and are not described again.

The middle layer is a high-heat-insulation barrier layer and comprises the following raw materials: 22.4% of low-density polyethylene (LDPE), 22.4% of linear low-density polyethylene (LLDPE), 44.9% of metallocene linear low-density polyethylene (mLLDPE), 5.0% of ageing-resistant master batch and 5.3% of barrier heat-insulating master batch.

The middle layer comprises the following raw materials in parts by weight: 25 parts of low-density polyethylene (LDPE), 25 parts of linear low-density polyethylene (LLDPE), 50 parts of metallocene linear low-density polyethylene, 5.6 parts of anti-aging master batch and 5.9 parts of barrier heat-insulating master batch.

The Melt Index (MI) of Low Density Polyethylene (LDPE) is 0.2-0.3g/10min, No. 2420D, Daqing petrochemical manufacturing, 25 parts; the Linear Low Density Polyethylene (LLDPE) has a Melt Index (MI) of 0.8-1.0g/10min, a mark number of 9085, manufactured by Tianjin carbon-linked method, of 25 parts; the metallocene linear low density polyethylene (m-LLDPE) has a Melt Index (MI) of 1.0g/10min under the designation 1018MA, manufactured by Exxon Mobil, of 50 parts; 5.6 parts of an anti-aging master batch; wherein the component content and the preparation method of the anti-aging master batch and the inner layer are not described; 5.9 parts of insulating master batch (the addition amount is reduced by 50 percent compared with that of the example 1).

The composition and preparation method of the barrier heat-preservation master batch are the same as those of the example 1 and are not described again.

The coating liquid was rated TG-150, manufactured by Nippon bamboo grease Co.

The preparation method of the heat-preservation long-acting dripping fog-dissipation greenhouse film in the comparative example 3 comprises the following steps: the heat-preservation long-acting dripping fog-dissipation greenhouse film is prepared by respectively mixing and stirring the component materials of the inner layer, the middle layer and the outer layer and master batch uniformly, adding the mixture into a three-layer co-extrusion extruder, and carrying out melt plasticizing blow molding, traction, cooling and shaping, corona, coating liquid impregnation, drying, edge welding, seam cutting, code spraying and folding.

The heat-insulating long-acting dripping fog-dispersal greenhouse film provided by the comparative example 3 has the advantages that the addition amount of the blocking heat-insulating master batch in the middle layer is reduced by 50% except that the light conversion master batch is not added in the outer layer and the dustproof master batch is not added in the inner layer, other material components and the preparation method are completely the same as those in the example 1, and the photosynthetic efficiency is reduced as long as the film does not have the functions of light modulation, light conversion and dust prevention. The effect of blocking and insulating at night in the greenhouse is poor, the ground temperature at night is reduced by 0.8-1.5 ℃, the ageing resistance, the long-acting dripping fog dissipation performance are the same as those of the greenhouse film in the example 1, the greenhouse film prepared in the comparative example 1 is already applied to the field of agricultural test bases of Zhenlujiazhuang and Gaozhuangshandong provinces under Laiwu, the greenhouse film is used for planting tomatoes, compared with the greenhouse film in the example 1, the fruit coloring mature period is 10-13 days later, and the yield is reduced by 13-17%.

Comparative example 4

The dustproof light-conversion high-heat-preservation long-acting dripping fog-dissipation greenhouse film in the comparative example 4 comprises an inner layer, a middle layer, an outer layer and a coating layer; the inner layer is a dustproof aging-resistant layer, and the raw materials comprise polyethylene, dustproof master batch and aging-resistant master batch; the middle layer is a high-heat-insulation barrier layer, and the raw materials comprise polyethylene, an anti-aging master batch and a barrier heat-insulation master batch; the outer layer is a light-adjusting and light-converting layer, and the raw materials comprise polyethylene, light-converting master batch and anti-aging master batch; the coating layer is a long-acting dripping fog-eliminating layer.

The components and the preparation method of the aging-resistant master batch are the same as those of the example 1 and are not described again.

The content and the preparation method of the components of the insulation master batch are the same as those of the example 1, and are not described again.

The outer layer is a light-adjusting and light-converting layer and comprises the following raw materials: 23.3 percent of Low Density Polyethylene (LDPE), 23.3 percent of Linear Low Density Polyethylene (LLDPE), 46.5 percent of metallocene linear low density polyethylene (mLLDPE), 5.1 percent of ageing-resistant master batch and 1.8 percent of light conversion master batch.

The outer layer comprises the following raw materials in parts by weight: 25 parts of low-density polyethylene (LDPE), 25 parts of powdery linear low-density polyethylene (LLDPE), 50 parts of metallocene linear low-density polyethylene (mLLDPE), 5.5 parts of anti-aging master batch and 2 parts of light conversion master batch.

The metallocene linear low density polyethylene (mLLDPE) has a Melt Index (MI) of 1.0g/10min, No. 2010MC, manufactured by Exxon Mobil, of 50 parts; 5.5 parts of an anti-aging master batch; the component content and the preparation method of the anti-aging master batch and the inner layer are not described; and 2 parts of light conversion master batch.

The components and the preparation method of the light conversion master batch are the same as those of the example 1 and are not described again.

The coating liquid was rated TG-150, manufactured by Nippon bamboo grease Co.

The preparation method of the dustproof light-conversion high-heat-preservation long-acting dripping fog-dissipation greenhouse film in the comparative example 4 comprises the following steps: the material and the master batch of each component of the inner layer, the middle layer and the outer layer are respectively mixed and stirred uniformly, added into a three-layer co-extrusion extruder, and subjected to melt plasticizing blow molding, traction, cooling and shaping, corona, coating solution impregnation, drying, edge welding, seam cutting, code spraying and folding to obtain the dustproof light-conversion high-heat-preservation long-acting dripping fog-dissipation greenhouse film.

The dustproof light conversion high-heat-preservation long-acting dripping fog dispersal greenhouse film provided by the comparative example 4 is 40% less than that of the example 1 except that the light conversion mother material is added on the outer layer, and the components of other materials are completely the same as those of the example 1 except that the light modulation and conversion functions are reduced and the photosynthetic efficiency is reduced. The dust-proof, high-heat-preservation, aging-resistant, long-acting dripping and fog-removing performances are the same as those of example 1, the greenhouse film prepared in the comparative example 4 is applied to the field of the agricultural big test base of Zhenlujiazhu and Gaozhuangshandong under Laiwu, and compared with the greenhouse film prepared in the example 1, the tomato planting method has the advantages that the fruit coloring and mature period is 5-7 days later, and the yield is 5-7 percent lower.

Comparative example 5

Comparative example 5 is different from example 1 in that the aging resistant master batch was not added to the outer layer, and only the light conversion master batch was added. The material composition of the other inner layer, middle layer and coating layer is the same as that of example 1, and the preparation process and parameters are the same. The service life of the greenhouse film can only reach two years.

Comparative example 6

Comparative example 6 is different from example 1 in that no coating layer was provided, and dripping master batch KF650 (manufactured by shanghai research corporation) was added to the middle layer of the film: 14%, adding dripping master batch KF-650: 10% and antifogging master batch AF-38 (manufactured by Shanghai research Co., Ltd.): 2 percent. The difference between the comparative example 6 and the example 1 is that the preparation process reduces the procedures of corona, impregnation and drying.

The shed film without the coating layer has the dripping fog dissipation function, dripping and fog dissipation master batches must be added into the film, and the dripping fog dissipation function is achieved through gradual segregation of the surfactant of the master batches in the film, the comparative example 6 belongs to an internal addition type, the dripping lasting period of the shed film is only 135 days, the cost performance is low, and the requirement of modern high-efficiency agricultural development cannot be met.

The mechanical and optical properties of the agricultural greenhouse film are tested according to national standard GB/T4455-2019, the test results of the mechanical properties and the light transmittance haze value of the product are shown in Table 2, and the product specification is 10M x 0.12 mm.

TABLE 2 test results of mechanical properties and haze of light transmittance of the product

The test results reflected in table 2 show that the mechanical property and optical property data of examples 1 to 4 and comparative examples 1 to 4 all exceed the national standard index requirements, and can meet the minimum requirements of greenhouse coverage.

TABLE 3 drip and fog dispersal water bath experiment

Table 3 testing of dripping fog dispersal performance according to the 4.6 dripping performance test in the standard "coating type durable dripping polyethylene greenhouse film" standard QB/T4475-2013, the 1-year-stage film experiment time is 30d, the 2-year-stage film experiment time is 45 days, the 3-year-stage film experiment time is 60 days, the 4-year-stage film experiment time is 75 days, and the 5-year-stage film experiment time is 90 days.

The data of the drip fog dispersal performance test of examples 1-4 and comparative examples 1-5 in Table 3 show that the lasting period of the drip fog dispersal function of the greenhouse film prepared by the coating type process can be synchronized with the service life of the greenhouse film. Comparative example 6 belongs to a greenhouse film prepared by an internal addition type process, and the test standard is according to the specification of 6.8 dripping performance in GB/T4455-2019.

The difference of the two types of droplet performance test time is enough to illustrate the good and bad effect of the effective period of the droplet fog dissipation function. As a covering material of an overwintering greenhouse, the dripping fog dissipation performance of the greenhouse film is a necessary key functional index, the dripping fog dissipation functional period of the comparative example 6 is short, the service life of the greenhouse film is one year, and the cost performance is low. Especially, in winter, the temperature difference between the indoor part and the outdoor part of the greenhouse is large, fog drops and water drops can be generated on the greenhouse film, sunlight transmission is blocked, photosynthesis is weakened, crop growth is affected, moisture can rise due to dew formation and water drops in the greenhouse, and crop downy mildew and plant diseases and insect pests are bred due to the fact that the water drops drop on crops, so that yield is reduced. The drip fog dispersal function of the greenhouse film is to reduce the formation of fog drops on the inner surface of the greenhouse film, change the water drops into water films and flow down along the film, and simultaneously reduce and eliminate the fog in the greenhouse and enhance the lighting effect of crops.

TABLE 4 detection result of indoor and outdoor light intensity ratio of light conversion effect shed

The test data of the indoor and outdoor light intensity ratio of the light conversion effect shed listed in table 4 is the detection result collected on the shed film in the field of the agricultural and agricultural test base below Laiwu by using a handheld portable fluorescence spectrometer and an illuminometer. The test data in table 4 show that the indoor and outdoor light intensity ratios of examples 1 to 4 are reduced in a small range along with the increase of the greenhouse covering time, the indoor and outdoor light intensity ratio of the greenhouse covering for eight months is kept above 88%, and the light conversion effect is obviously better than that of comparative examples 1 to 3, and is only kept about 70%. The light intensity ratio plays a key role in enhancing the photosynthetic efficiency of crops, promoting the growth of crops, increasing the early maturity and the yield and improving the quality.

TABLE 5 test results of dust test

The test data in table 5 are measurements taken on a field booth at the town agricultural large test base below leuw using a hand-held light transmission instrument from 20/10/2016 to 20/10/2020.

The detection data in table 5 show that the light transmittance of examples 1 to 4 and comparative examples 1 and 4 is reduced to a small extent with the increase of the ceiling-covering time, and the dustproof effect is significantly better than that of comparative examples 2 to 3. The high light transmittance is a necessary condition for promoting the growth and photosynthesis of crops. It is necessary to add the dustproof function to the greenhouse film with long service life.

In conclusion, the coating type light-dimming dust-preventing high-heat-preservation long-acting dripping fog-dispersing greenhouse film disclosed by the invention realizes the comprehensive functions of dust prevention, light dimming, light conversion and high heat preservation in the long-acting dripping fog-dispersing and long-life greenhouse film. Represents the direction of high-end development of the current agricultural greenhouse film, and accords with the concept of resource conservation and environmental protection.

Comparative example 5 is different from example 1 in that no coating layer was provided. The greenhouse film without the coating layer has the dripping fog dissipation function, only the dripping fog dissipation master batch is added to the middle layer and the outer layer of the greenhouse film, the fog dissipation function is achieved through gradual evolution of the surfactant of the master batch in the film, the dripping lasting period of the internal addition type greenhouse film is only 4-6 months generally, and the cost performance is low, so that the requirement of modern high-efficiency agricultural development cannot be met.

Comparative example 6 is different from example 1 in that the aging resistant master batch was not added to the outer layer, and only the light conversion master batch was added. The material composition of the other inner layer, middle layer and coating layer is the same as that of example 1, and the preparation process and parameters are the same. The service life of the greenhouse film can only reach two years.

The weather resistance of the greenhouse films prepared in the embodiments 1 to 3 is tested, and the experimental equipment adopts a xenon lamp weathering box and is tested according to the GB/T16422.2-2014 plastic laboratory light source exposure experimental method; the samples were soaked in 0.05mol/L sulfurous acid for 24 hours every five weeks (840 hours), and after washing, the aging test was continued until 4200 hours were completed. The test items were tensile strength and elongation at break.

Table 6 tensile strength test results

Table 7 tensile strength retention test results

TABLE 8 elongation at break test results

TABLE 8 retention of elongation at break test results

The experimental data prove that the light stabilizer grade which is preferred by the invention is reliable in aging resistance after the greenhouse film is prepared.

Claims

1. The utility model provides a long-term stream of coating type dustproof high heat preservation of adjusting luminance fog dispersal canopy membrane that drips which characterized in that: comprises an inner layer, a middle layer, an outer layer and a coating layer; the inner layer is a dustproof aging-resistant layer and comprises the following raw materials in percentage by mass: 20 to 25 percent of low density polyethylene, 20 to 25 percent of linear low density polyethylene, 30 to 47 percent of metallocene linear low density polyethylene, 4.5 to 10 percent of anti-aging master batch and 8 to 12 percent of dustproof master batch; the middle layer is a high-heat-insulation barrier layer and comprises the following raw materials in percentage by mass: 20-25% of low-density polyethylene, 20-25% of linear low-density polyethylene, 30-50% of metallocene linear low-density polyethylene, 4.5-10% of anti-aging master batch and 5-10.5% of barrier heat-insulation master batch; the outer layer is a light-adjusting and light-converting layer and comprises the following raw materials in percentage by mass: 20-25% of low-density polyethylene, 20-25% of linear low-density polyethylene, 35-50% of metallocene linear low-density polyethylene, 5-10% of anti-aging master batch and 2-5% of light conversion master batch; the coating layer is a long-acting dripping fog-dissipating layer;

wherein:

the coating layer is a coating liquid dry matter prepared from inorganic aluminum sol, silica sol and organic mixed glue solution; the coating layer comprises the following raw materials in percentage by mass: 6-8% of coating liquid stock solution and 92-90% of deionized water;

the dustproof master batch comprises the following raw materials in percentage by mass: 50-70% of low-density polyethylene, 20-30% of linear low-density polyethylene, 3-10% of fluoroelastomer, 4-7% of stearic acid metal soap and 1-3% of amide;

the anti-aging master batch comprises the following raw materials in percentage by mass: 40-45% of low-density polyethylene, 29.5-40% of linear low-density polyolefin, 12-24% of light stabilizer, 3-4% of antioxidant and 0.5-1.8% of hydrotalcite acid acceptor;

the light conversion master batch in the outer layer raw materials comprises the following raw materials in percentage by mass: 50-60% of low-density polyethylene, 32-38% of linear low-density polyethylene and 8-12% of light conversion agent;

the heat insulation barrier master batch comprises the following raw materials in percentage by mass: 20-30% of low-density polyethylene, 10-20% of linear low-density polyethylene and 50-70% of hydrotalcite heat insulating agent;

the thickness ratio of the inner layer, the middle layer and the outer layer is 0.8-1.2:1.2-0.8:1, and the dry matter content of the dried coating solution of the coating layer is more than 0.20g/m²；

The width of the coating type light-dimming dustproof high-heat-preservation long-acting dripping fog-dispersal shed film is more than 10M, the thickness of the film is 0.10-0.18mm, the light transmittance is more than 90%, the haze is less than 16%, the light intensity ratio inside and outside the greenhouse is more than 75%, the photosynthetic efficiency is improved by more than 30% through light wave optimization, and the duration of the dripping fog-dispersal dustproof function is more than 5 years.

2. The coating type light-dimming dust-proof high-heat-preservation long-acting dripping fog-dispersal greenhouse film as claimed in claim 1, which is characterized in that: the melt index of the low-density polyethylene in the dustproof master batch is 2.0g/10 min; the linear low density polyethylene has a melt index of 2.0g/10 min; the fluoroelastomer is any one of PPA2100 or PPA 5924; the stearic acid metal soap is one of calcium stearate or zinc stearate; the amide is erucamide.

3. The coating type dimming dustproof high-heat-preservation long-acting dripping fog dispersal greenhouse film as claimed in claim 1, which is characterized in that: the melt index of the low-density polyethylene in the aging-resistant master batch is 2.0g/10 min; the linear low density polyethylene has a melt index of 2.0g/10 min; the light stabilizer is hindered amine light stabilizer; the antioxidant is a compound of hindered phenols and phosphites; the hydrotalcite acid acceptor is any one of HTP or HTB;

the light conversion agent in the light conversion master batch is an inorganic rare earth light conversion agent, and the inorganic rare earth light conversion agent is any one or more of green-to-red GTR-650, purple-to-blue VTB-440, purple-to-red VTR660 or red-to-blue dual-light RBI 6545.

4. A preparation method of the coating type dimming dustproof high-heat-preservation long-acting dripping fog dispersal greenhouse film as defined in claim 1 is characterized by comprising the following steps: the coating type light-adjusting, dustproof, high-heat-preservation, long-acting dripping and fog-dispersing greenhouse film is prepared by uniformly mixing and stirring the component materials of the inner layer, the middle layer and the outer layer, adding the mixture into a three-layer co-extrusion extruder, and carrying out melt plasticizing blow molding, traction, cooling and shaping, corona, coating liquid impregnation, drying, edge welding, seam cutting and folding.